# To get started with Dependabot version updates, you'll need to specify which
# package ecosystems to update and where the package manifests are located.
# Please see the documentation for all configuration options:
# https://help.github.com/github/administering-a-repository/configuration-options-for-dependency-updates

version: 2
updates:
  - package-ecosystem: "gomod" # See documentation for possible values
    directory: "/" # Location of package manifests
    schedule:
      interval: "daily"
    rebase-strategy: "disabled"

//-----------------------------------------------------------------------------
// Copyright (c) 2021-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2021-present Detlef Stern
//-----------------------------------------------------------------------------

// Package api contains common definitions used for client and server.
package api

// ZettelID contains the identifier of a zettel. It is a string with 14 digits.
type ZettelID string

// InvalidZID is an invalif zettel identifier
// InvalidZID is an invalid zettel identifier
const InvalidZID = ""

// IsValid returns true, if the idenfifier contains 14 digits.
func (zid ZettelID) IsValid() bool {
	if len(zid) != 14 {
		return false
	}
	for i := 0; i < 14; i++ {
	for i := range 14 {
		ch := zid[i]
		if ch < '0' || '9' < ch {
			return false
		}
	}
	return true
}

// ZettelMeta is a map containg the metadata of a zettel.
type ZettelMeta map[string]string

// ZettelRights is an integer that encode access rights for a zettel.
type ZettelRights uint8

// Values for ZettelRights, can be or-ed
const (
	ZettelCanNone   ZettelRights = 1 << iota
	ZettelCanCreate              // Current user is allowed to create a new zettel
	ZettelCanRead                // Requesting user is allowed to read the zettel
	ZettelCanWrite               // Requesting user is allowed to update the zettel
	ZettelCanRename              // Requesting user is allowed to provide the zettel with a new identifier
	placeholder_1                // Was assigned to rename right, which is now removed
	ZettelCanDelete              // Requesting user is allowed to delete the zettel
	ZettelMaxRight               // Sentinel value
)

// MetaRights contains the metadata of a zettel, and its rights.
type MetaRights struct {
	Meta   ZettelMeta

//-----------------------------------------------------------------------------
// Copyright (c) 2021-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2021-present Detlef Stern
//-----------------------------------------------------------------------------

package api

import "fmt"

// Predefined Zettel Identifier
const (
	// System zettel
	ZidVersion              = ZettelID("00000000000001")
	ZidHost                 = ZettelID("00000000000002")
	ZidOperatingSystem      = ZettelID("00000000000003")
	ZidLicense              = ZettelID("00000000000004")
	ZidAuthors              = ZettelID("00000000000005")
	ZidDependencies         = ZettelID("00000000000006")
	ZidLog                  = ZettelID("00000000000007")
	ZidBoxManager           = ZettelID("00000000000020")
	ZidMetadataKey          = ZettelID("00000000000090")
	ZidParser               = ZettelID("00000000000092")
	ZidStartupConfiguration = ZettelID("00000000000096")
	ZidConfiguration        = ZettelID("00000000000100")
	ZidVersion              = ZettelID("00000000000001") // -> 0001
	ZidHost                 = ZettelID("00000000000002") // -> 0002
	ZidOperatingSystem      = ZettelID("00000000000003") // -> 0003
	ZidLicense              = ZettelID("00000000000004") // -> 0004
	ZidAuthors              = ZettelID("00000000000005") // -> 0005
	ZidDependencies         = ZettelID("00000000000006") // -> 0006
	ZidLog                  = ZettelID("00000000000007") // -> 0007
	ZidMemory               = ZettelID("00000000000008") // -> 0008
	ZidSx                   = ZettelID("00000000000009") // -> 0009
	ZidHTTP                 = ZettelID("00000000000010") // -> 000a
	ZidAPI                  = ZettelID("00000000000011") // -> 000b
	ZidWebUI                = ZettelID("00000000000012") // -> 000c
	ZidConsole              = ZettelID("00000000000013") // -> 000d
	ZidBoxManager           = ZettelID("00000000000020") // -> 000e
	ZidZettel               = ZettelID("00000000000021") // -> 000f
	ZidIndex                = ZettelID("00000000000022") // -> 000g
	ZidQuery                = ZettelID("00000000000023") // -> 000h
	ZidMetadataKey          = ZettelID("00000000000090") // -> 000i
	ZidParser               = ZettelID("00000000000092") // -> 000j
	ZidStartupConfiguration = ZettelID("00000000000096") // -> 000k
	ZidConfiguration        = ZettelID("00000000000100") // -> 000l
	ZidDirectory            = ZettelID("00000000000101") // -> 000m
	ZidWarnings             = ZettelID("00000000000102") // -> 000n

	// WebUI HTML templates are in the range 10000..19999
	ZidBaseTemplate   = ZettelID("00000000010100")
	ZidLoginTemplate  = ZettelID("00000000010200")
	ZidListTemplate   = ZettelID("00000000010300")
	ZidZettelTemplate = ZettelID("00000000010401")
	ZidInfoTemplate   = ZettelID("00000000010402")
	ZidFormTemplate   = ZettelID("00000000010403")
	ZidBaseTemplate   = ZettelID("00000000010100") // -> 000s
	ZidLoginTemplate  = ZettelID("00000000010200") // -> 000t
	ZidListTemplate   = ZettelID("00000000010300") // -> 000u
	ZidZettelTemplate = ZettelID("00000000010401") // -> 000v
	ZidInfoTemplate   = ZettelID("00000000010402") // -> 000w
	ZidFormTemplate   = ZettelID("00000000010403") // -> 000x
	ZidRenameTemplate = ZettelID("00000000010404")
	ZidDeleteTemplate = ZettelID("00000000010405")
	ZidErrorTemplate  = ZettelID("00000000010700")
	ZidDeleteTemplate = ZettelID("00000000010405") // -> 000y
	ZidErrorTemplate  = ZettelID("00000000010700") // -> 000z

	// WebUI sxn code zettel are in the range 19000..19999
	ZidSxnTemplate = ZettelID("00000000019100")
	ZidSxnStart = ZettelID("00000000019000") // -> 000q
	ZidSxnBase  = ZettelID("00000000019990") // -> 000r

	// CSS-related zettel are in the range 20000..29999
	ZidBaseCSS    = ZettelID("00000000020001")
	ZidUserCSS    = ZettelID("00000000025001")
	ZidBaseCSS = ZettelID("00000000020001") // -> 0010
	ZidUserCSS = ZettelID("00000000025001") // -> 0011
	ZidRoleCSSMap = ZettelID("00000000029000") // Maps roles to CSS zettel, which should be in the range 29001..29999.

	// WebUI JS zettel are in the range 30000..39999

	// WebUI image zettel are in the range 40000..49999
	ZidEmoji = ZettelID("00000000040001")
	ZidEmoji = ZettelID("00000000040001") // -> 000o

	// Other sxn code zettel are in the range 50000..59999
	ZidSxnPrelude = ZettelID("00000000059900") // -> 000p

	// Predefined Zettelmarkup zettel are in the range 60000..69999
	ZidRoleZettelZettel        = ZettelID("00000000060010") // -> 0012
	ZidRoleConfigurationZettel = ZettelID("00000000060020") // -> 0013
	ZidRoleRoleZettel          = ZettelID("00000000060030") // -> 0014
	ZidRoleTagZettel           = ZettelID("00000000060040") // -> 0015

	// Range 90000...99999 is reserved for zettel templates
	ZidTOCNewTemplate    = ZettelID("00000000090000")
	ZidTemplateNewZettel = ZettelID("00000000090001")
	ZidTemplateNewUser   = ZettelID("00000000090002")
	ZidTOCNewTemplate    = ZettelID("00000000090000") // -> 0016
	ZidTemplateNewZettel = ZettelID("00000000090001") // -> 0017
	ZidTemplateNewRole   = ZettelID("00000000090004") // -> 001a
	ZidTemplateNewTag    = ZettelID("00000000090003") // -> 0019
	ZidTemplateNewUser   = ZettelID("00000000090002") // -> 0018

	ZidSession      = ZettelID("00009999999997") // -> 00zx
	ZidAppDirectory = ZettelID("00009999999998") // -> 00zy
	ZidMapping      = ZettelID("00009999999999") // -> 00zz
	ZidDefaultHome = ZettelID("00010000000000")
	ZidDefaultHome  = ZettelID("00010000000000") // -> 0100
)

// LengthZid factors the constant length of a zettel identifier
const LengthZid = len(ZidDefaultHome)

// Values of the metadata key/value type.
const (
	MetaCredential   = "Credential"
	MetaEmpty        = "EString"
	MetaID           = "Identifier"
	MetaIDSet        = "IdentifierSet"
	MetaNumber       = "Number"
	MetaString       = "String"
	MetaTagSet       = "TagSet"
	MetaTimestamp    = "Timestamp"
	MetaURL          = "URL"
	MetaWord         = "Word"
	MetaWordSet      = "WordSet"
	MetaZettelmarkup = "Zettelmarkup"
)

// Predefined general Metadata keys
const (
	KeyID           = "id"
	KeyTitle        = "title"

// Predefined Metadata values
const (
	ValueFalse             = "false"
	ValueTrue              = "true"
	ValueLangEN            = "en"
	ValueRoleConfiguration = "configuration"
	ValueRoleTag           = "tag"
	ValueRoleRole          = "role"
	ValueRoleZettel        = "zettel"
	ValueSyntaxCSS         = "css"
	ValueSyntaxDraw        = "draw"
	ValueSyntaxGif         = "gif"
	ValueSyntaxHTML        = "html"
	ValueSyntaxMarkdown    = "markdown"
	ValueSyntaxMD          = "md"

	ValueVisibilityLogin   = "login"
	ValueVisibilityOwner   = "owner"
	ValueVisibilityPublic  = "public"
)

// Additional HTTP constants.
const (
	MethodMove = "MOVE" // HTTP method for renaming a zettel

	HeaderAccept      = "Accept"
	HeaderContentType = "Content-Type"
	HeaderDestination = "Destination"
	HeaderLocation    = "Location"
)

// Values for HTTP query parameter.
const (
	QueryKeyCommand   = "cmd"
	QueryKeyEncoding  = "enc"
	QueryKeyParseOnly = "parseonly"
	QueryKeyPart      = "part"
	QueryKeyPhrase    = "phrase"
	QueryKeyQuery     = "q"
	QueryKeyRole      = "role"
	QueryKeySeed      = "_seed"
	QueryKeyTag       = "tag"
)

// Supported encoding values.
const (
	EncodingHTML  = "html"
	EncodingMD    = "md"
	EncodingSHTML = "shtml"
	EncodingSz    = "sz"
	EncodingText  = "text"
	EncodingZMK   = "zmk"

	EncodingPlain = "plain"
	EncodingData  = "data"
	EncodingJson  = "json"
)

var mapEncodingEnum = map[string]EncodingEnum{
	EncodingHTML:  EncoderHTML,
	EncodingMD:    EncoderMD,
	EncodingSHTML: EncoderSHTML,
	EncodingSz:    EncoderSz,
	EncodingText:  EncoderText,
	EncodingZMK:   EncoderZmk,

	EncodingPlain: EncoderPlain,
	EncodingData:  EncoderData,
	EncodingJson:  EncoderJson,
}
var mapEnumEncoding = map[EncodingEnum]string{}

func init() {
	for k, v := range mapEncodingEnum {
		mapEnumEncoding[v] = k
	}

	EncoderSHTML
	EncoderSz
	EncoderText
	EncoderZmk

	EncoderPlain
	EncoderData
	EncoderJson
)

// String representation of an encoder key.
func (e EncodingEnum) String() string {
	if f, ok := mapEnumEncoding[e]; ok {
		return f
	}

// Supported search operator representations
const (
	BackwardDirective = "BACKWARD"
	ContextDirective  = "CONTEXT"
	CostDirective     = "COST"
	ForwardDirective  = "FORWARD"
	FullDirective     = "FULL"
	IdentDirective    = "IDENT"
	ItemsDirective    = "ITEMS"
	MaxDirective      = "MAX"
	LimitDirective    = "LIMIT"
	OffsetDirective   = "OFFSET"
	OrDirective       = "OR"
	OrderDirective    = "ORDER"
	PhraseDirective   = "PHRASE"
	PickDirective     = "PICK"
	RandomDirective   = "RANDOM"
	ReverseDirective  = "REVERSE"
	UnlinkedDirective = "UNLINKED"

	ActionSeparator = "|"

	AtomAction     = "ATOM"
	KeysAction     = "KEYS"
	MinAction      = "MIN"
	MaxAction      = "MAX"
	NumberedAction = "NUMBERED"
	RedirectAction = "REDIRECT"
	ReIndexAction  = "REINDEX"
	RSSAction      = "RSS"
	TitleAction    = "TITLE"

	ExistOperator    = "?"
	ExistNotOperator = "!?"

	SearchOperatorNot        = "!"
	SearchOperatorEqual      = "="
	SearchOperatorNotEqual   = "!="
	SearchOperatorHas        = ":"
	SearchOperatorHasNot     = "!:"
	SearchOperatorPrefix     = "["
	SearchOperatorNoPrefix   = "!["
	SearchOperatorSuffix     = "]"
	SearchOperatorNoSuffix   = "!]"
	SearchOperatorMatch      = "~"
	SearchOperatorNoMatch    = "!~"
	SearchOperatorLess       = "<"
	SearchOperatorNotLess    = "!<"
	SearchOperatorGreater    = ">"
	SearchOperatorNotGreater = "!>"
)

// QueryPrefix is the prefix that denotes a query expression within a reference.
const QueryPrefix = "query:"

//-----------------------------------------------------------------------------
// Copyright (c) 2020-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2020-present Detlef Stern
//-----------------------------------------------------------------------------

package api

import (
import "t73f.de/r/webs/urlbuilder"
	"net/url"
	"strings"
)

type urlQuery struct{ key, val string }

// URLBuilder should be used to create zettelstore URLs.
type URLBuilder struct {
	base   urlbuilder.URLBuilder
	prefix   string
	prefix string
	key      byte
	rawLocal string
	path     []string
	query    []urlQuery
	fragment string
}

// NewURLBuilder creates a new URL builder with the given prefix and key.
func NewURLBuilder(prefix string, key byte) *URLBuilder {
	for len(prefix) > 0 && prefix[len(prefix)-1] == '/' {
		prefix = prefix[0 : len(prefix)-1]
	}
	return &URLBuilder{prefix: prefix, key: key}
	result := URLBuilder{prefix: prefix}
	if key != '/' {
		result.base.AddPath(string([]byte{key}))
	}
	return &result
}

// Clone an URLBuilder
func (ub *URLBuilder) Clone() *URLBuilder {
	cpy := new(URLBuilder)
	cpy.key = ub.key
	ub.base.Copy(&cpy.base)
	if len(ub.path) > 0 {
		cpy.path = make([]string, 0, len(ub.path))
		cpy.path = append(cpy.path, ub.path...)
	}
	if len(ub.query) > 0 {
		cpy.query = make([]urlQuery, 0, len(ub.query))
		cpy.query = append(cpy.query, ub.query...)
	}
	cpy.fragment = ub.fragment
	cpy.prefix = ub.prefix
	return cpy
}

// SetRawLocal sets everything that follows the prefix / key.
func (ub *URLBuilder) SetRawLocal(rawLocal string) *URLBuilder {
	for len(rawLocal) > 0 && rawLocal[0] == '/' {
		rawLocal = rawLocal[1:]
	}
	ub.rawLocal = rawLocal
	ub.path = nil
	ub.query = nil
	ub.fragment = ""
	return ub
}

// SetZid sets the zettel identifier.
func (ub *URLBuilder) SetZid(zid ZettelID) *URLBuilder {
	if len(ub.path) > 0 {
		panic("Cannot add Zid")
	}
	ub.rawLocal = ""
	ub.path = append(ub.path, string(zid))
	ub.base.AddPath(string(zid))
	return ub
}

// AppendPath adds a new path element
func (ub *URLBuilder) AppendPath(p string) *URLBuilder {
	ub.rawLocal = ""
	ub.base.AddPath(p)
	for len(p) > 0 && p[0] == '/' {
		p = p[1:]
	}
	if p != "" {
		ub.path = append(ub.path, p)
	}
	return ub
}

// AppendKVQuery adds a new key/value query parameter
func (ub *URLBuilder) AppendKVQuery(key, value string) *URLBuilder {
	ub.rawLocal = ""
	ub.query = append(ub.query, urlQuery{key, value})
	ub.base.AddQuery(key, value)
	return ub
}

// AppendQuery adds a new query
func (ub *URLBuilder) AppendQuery(value string) *URLBuilder {
	if value != "" {
		ub.rawLocal = ""
		ub.query = append(ub.query, urlQuery{QueryKeyQuery, value})
		ub.base.AddQuery(QueryKeyQuery, value)
	}
	return ub
}

// ClearQuery removes all query parameters.
func (ub *URLBuilder) ClearQuery() *URLBuilder {
	ub.rawLocal = ""
	ub.query = nil
	ub.base.RemoveQueries()
	ub.fragment = ""
	return ub
}

// SetFragment stores the fragment
func (ub *URLBuilder) SetFragment(s string) *URLBuilder {
	ub.rawLocal = ""
	ub.fragment = s
	ub.base.SetFragment(s)
	return ub
}

// String produces a string value.
func (ub *URLBuilder) String() string {
	var sb strings.Builder

	return ub.prefix + ub.base.String()
	sb.WriteString(ub.prefix)
	if ub.key != '/' {
		sb.WriteByte(ub.key)
	}
	if ub.rawLocal != "" {
		sb.WriteString(ub.rawLocal)
		return sb.String()
	}
	for i, p := range ub.path {
		if i > 0 || ub.key != '/' {
			sb.WriteByte('/')
		}
		sb.WriteString(url.PathEscape(p))
	}
	if len(ub.fragment) > 0 {
		sb.WriteByte('#')
		sb.WriteString(ub.fragment)
	}
	for i, q := range ub.query {
		if i == 0 {
			sb.WriteByte('?')
		} else {
			sb.WriteByte('&')
		}
		sb.WriteString(q.key)
		if val := q.val; val != "" {
			sb.WriteByte('=')
			sb.WriteString(url.QueryEscape(val))
		}
	}
	return sb.String()
}

//-----------------------------------------------------------------------------
// Copyright (c) 2020-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2020-present Detlef Stern
//-----------------------------------------------------------------------------

// Package attrs stores attributes of zettel parts.
package attrs

import (
	"slices"
	"strings"

	"zettelstore.de/client.fossil/maps"
	"t73f.de/r/zsc/maps"
)

// Attributes store additional information about some node types.
type Attributes map[string]string

// IsEmpty returns true if there are no attributes.
func (a Attributes) IsEmpty() bool { return len(a) == 0 }

func (a Attributes) Remove(key string) Attributes {
	if a != nil {
		delete(a, key)
	}
	return a
}

// AddClass adds a value to the class attribute.
func (a Attributes) AddClass(class string) Attributes {
// Add a value to an attribute key.
func (a Attributes) Add(key, value string) Attributes {
	if a == nil {
		return map[string]string{"class": class}
		return map[string]string{key: value}
	}
	classes := a.GetClasses()
	for _, cls := range classes {
		if cls == class {
			return a
		}
	}
	values := a.Values(key)
	if !slices.Contains(values, value) {
		values = append(values, value)
		a[key] = strings.Join(values, " ")
	}
	return a
}

	classes = append(classes, class)
	a["class"] = strings.Join(classes, " ")
	return a
}

// Values are the space separated values of an attribute.
func (a Attributes) Values(key string) []string {
	if a != nil {
		if value, ok := a[key]; ok {
			return strings.Fields(value)
		}
	}
// GetClasses returns the class values as a string slice
func (a Attributes) GetClasses() []string {
	if a == nil {
		return nil
	}
	return nil
}
	classes, ok := a["class"]
	if !ok {
		return nil
	}
	return strings.Fields(classes)

// Has the attribute key a value?
func (a Attributes) Has(key, value string) bool {
	return slices.Contains(a.Values(key), value)
}

// HasClass returns true, if attributes contains the given class.
func (a Attributes) HasClass(s string) bool {
// AddClass adds a value to the class attribute.
func (a Attributes) AddClass(class string) Attributes { return a.Add("class", class) }
	if a == nil {
		return false
	}
	classes, found := a["class"]

// GetClasses returns the class values as a string slice
	if !found {
		return false
	}
	return strings.Contains(" "+classes+" ", " "+s+" ")
func (a Attributes) GetClasses() []string { return a.Values("class") }

// HasClass returns true, if attributes contains the given class.
}
func (a Attributes) HasClass(s string) bool { return a.Has("class", s) }

//-----------------------------------------------------------------------------
// Copyright (c) 2020-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2020-present Detlef Stern
//-----------------------------------------------------------------------------

package attrs_test

import (
	"testing"

	"zettelstore.de/client.fossil/attrs"
	"t73f.de/r/zsc/attrs"
)

func TestHasDefault(t *testing.T) {
	t.Parallel()
	attr := attrs.Attributes{}
	if attr.HasDefault() {
		t.Error("Should not have default attr")

func TestHasClass(t *testing.T) {
	t.Parallel()
	testcases := []struct {
		classes string
		class   string
		exp     bool
	}{
		{"", "", true},
		{"", "", false},
		{"x", "", false},
		{"x", "x", true},
		{"x", "y", false},
		{"abc def ghi", "abc", true},
		{"abc def ghi", "def", true},
		{"abc def ghi", "ghi", true},
		{"ab de gi", "b", false},

//-----------------------------------------------------------------------------
// Copyright (c) 2021-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2021-present Detlef Stern
//-----------------------------------------------------------------------------

// Package client provides a client for accessing the Zettelstore via its API.
package client

import (
	"bufio"
	"bytes"
	"context"
	"fmt"
	"io"
	"net"
	"net/http"
	"net/url"
	"strconv"
	"strings"
	"time"

	"zettelstore.de/client.fossil/api"
	"zettelstore.de/client.fossil/sexp"
	"zettelstore.de/sx.fossil"
	"zettelstore.de/sx.fossil/sxreader"
	"t73f.de/r/sx"
	"t73f.de/r/sx/sxreader"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/sexp"
	"t73f.de/r/zsc/sz"
)

// Client contains all data to execute requests.
type Client struct {
	base      string
	username  string
	password  string

	myURL := *u
	myURL.User = nil
	myURL.ForceQuery = false
	myURL.RawQuery = ""
	myURL.Fragment = ""
	myURL.RawFragment = ""
	base := myURL.String()
	if !strings.HasSuffix(base, "/") {
		base += "/"
	}
	c := Client{
		base: base,
		client: http.Client{
			Timeout: 10 * time.Second,
			Transport: &http.Transport{
				DialContext: (&net.Dialer{
					Timeout: 5 * time.Second, // TCP connect timeout
				}).DialContext,
				TLSHandshakeTimeout: 5 * time.Second,
			},
		},
	}
	return &c
}

// AllowRedirect will modify the client to not follow redirect status code when
// using the Zettelstore. The original behaviour can be restored by settinh
// "allow" to false.
func (c *Client) AllowRedirect(allow bool) {
	if allow {
		c.client.CheckRedirect = func(req *http.Request, via []*http.Request) error {
			return http.ErrUseLastResponse
		}
	} else {
		c.client.CheckRedirect = nil
	}
}

// Error encapsulates the possible client call errors.
type Error struct {
	StatusCode int
	Message    string
	Body       []byte
}

	return &Error{
		StatusCode: resp.StatusCode,
		Message:    resp.Status[4:],
		Body:       body,
	}
}

// NewURLBuilder creates a new URL builder for the client with the given key.
func (c *Client) newURLBuilder(key byte) *api.URLBuilder {
func (c *Client) NewURLBuilder(key byte) *api.URLBuilder {
	return api.NewURLBuilder(c.base, key)
}
func (*Client) newRequest(ctx context.Context, method string, ub *api.URLBuilder, body io.Reader) (*http.Request, error) {
	return http.NewRequestWithContext(ctx, method, ub.String(), body)
}

func (c *Client) executeRequest(req *http.Request) (*http.Response, error) {
	if c.token != "" {
		req.Header.Add("Authorization", c.tokenType+" "+c.token)
	}
	resp, err := c.client.Do(req)
	if err != nil {
		if resp != nil && resp.Body != nil {
			resp.Body.Close()
			_ = resp.Body.Close()
		}
		return nil, err
	}
	return resp, err
}

func (c *Client) buildAndExecuteRequest(
	ctx context.Context, method string, ub *api.URLBuilder, body io.Reader, h http.Header) (*http.Response, error) {
	ctx context.Context,
	method string,
	ub *api.URLBuilder,
	body io.Reader,
) (*http.Response, error) {
	req, err := c.newRequest(ctx, method, ub, body)
	if err != nil {
		return nil, err
	}
	err = c.updateToken(ctx)
	if err != nil {
		return nil, err
	}
	for key, val := range h {
		req.Header[key] = append(req.Header[key], val...)
	}
	return c.executeRequest(req)
}

// SetAuth sets authentication data.
func (c *Client) SetAuth(username, password string) {
	c.username = username
	c.password = password

	if err != nil {
		return err
	}
	vals, err := sexp.ParseList(obj, "ssi")
	if err != nil {
		return err
	}
	token := vals[1].(sx.String).String()
	token := vals[1].(sx.String).GetValue()
	if len(token) < 4 {
		return fmt.Errorf("no valid token found: %q", token)
	}
	c.token = token
	c.tokenType = vals[0].(sx.String).String()
	c.tokenType = vals[0].(sx.String).GetValue()
	c.expires = time.Now().Add(time.Duration(vals[2].(sx.Int64)*9/10) * time.Second)
	return nil
}

func (c *Client) updateToken(ctx context.Context) error {
	if c.username == "" {
		return nil
	}
	if time.Now().After(c.expires) {
		return c.Authenticate(ctx)
	}
	return c.RefreshToken(ctx)
}

// Authenticate sets a new token by sending user name and password.
func (c *Client) Authenticate(ctx context.Context) error {
	authData := url.Values{"username": {c.username}, "password": {c.password}}
	req, err := c.newRequest(ctx, http.MethodPost, c.newURLBuilder('a'), strings.NewReader(authData.Encode()))
	req, err := c.newRequest(ctx, http.MethodPost, c.NewURLBuilder('a'), strings.NewReader(authData.Encode()))
	if err != nil {
		return err
	}
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
	return c.executeAuthRequest(req)
}

// RefreshToken updates the access token
func (c *Client) RefreshToken(ctx context.Context) error {
	req, err := c.newRequest(ctx, http.MethodPut, c.newURLBuilder('a'), nil)
	req, err := c.newRequest(ctx, http.MethodPut, c.NewURLBuilder('a'), nil)
	if err != nil {
		return err
	}
	return c.executeAuthRequest(req)
}

// CreateZettel creates a new zettel and returns its URL.
func (c *Client) CreateZettel(ctx context.Context, data []byte) (api.ZettelID, error) {
	ub := c.newURLBuilder('z')
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodPost, ub, bytes.NewBuffer(data), nil)
	ub := c.NewURLBuilder('z')
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodPost, ub, bytes.NewBuffer(data))
	if err != nil {
		return api.InvalidZID, err
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusCreated {
		return api.InvalidZID, statusToError(resp)
	}

// CreateZettelData creates a new zettel and returns its URL.
func (c *Client) CreateZettelData(ctx context.Context, data api.ZettelData) (api.ZettelID, error) {
	var buf bytes.Buffer
	if _, err := sx.Print(&buf, sexp.EncodeZettel(data)); err != nil {
		return api.InvalidZID, err
	}
	ub := c.newURLBuilder('z').AppendKVQuery(api.QueryKeyEncoding, api.EncodingData)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodPost, ub, &buf, nil)
	ub := c.NewURLBuilder('z').AppendKVQuery(api.QueryKeyEncoding, api.EncodingData)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodPost, ub, &buf)
	if err != nil {
		return api.InvalidZID, err
	}
	defer resp.Body.Close()
	rdr := sxreader.MakeReader(resp.Body)
	obj, err := rdr.Read()
	if resp.StatusCode != http.StatusCreated {
		return api.InvalidZID, statusToError(resp)
	}
	if err != nil {
		return api.InvalidZID, err
	}
	return makeZettelID(obj)
}

var bsLF = []byte{'\n'}

// QueryZettel returns a list of all Zettel.
func (c *Client) QueryZettel(ctx context.Context, query string) ([][]byte, error) {
	ub := c.newURLBuilder('z').AppendQuery(query)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil, nil)
	ub := c.NewURLBuilder('z').AppendQuery(query)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()
	data, err := io.ReadAll(resp.Body)
	switch resp.StatusCode {
	case http.StatusOK:

		lines = lines[:len(lines)-1]
	}
	return lines, nil
}

// QueryZettelData returns a list of zettel metadata.
func (c *Client) QueryZettelData(ctx context.Context, query string) (string, string, []api.ZidMetaRights, error) {
	ub := c.newURLBuilder('z').AppendKVQuery(api.QueryKeyEncoding, api.EncodingData).AppendQuery(query)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil, nil)
	ub := c.NewURLBuilder('z').AppendKVQuery(api.QueryKeyEncoding, api.EncodingData).AppendQuery(query)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil)
	if err != nil {
		return "", "", nil, err
	}
	defer resp.Body.Close()
	rdr := sxreader.MakeReader(resp.Body)
	obj, err := rdr.Read()
	switch resp.StatusCode {

		return "", "", nil, err
	}
	hVals, err := sexp.ParseList(vals[2], "ys")
	if err != nil {
		return "", "", nil, err
	}
	metaList, err := parseMetaList(vals[3].(*sx.Pair))
	return qVals[1].String(), hVals[1].String(), metaList, err
	return sz.GoValue(qVals[1]), sz.GoValue(hVals[1]), metaList, err
}

func parseMetaList(metaPair *sx.Pair) ([]api.ZidMetaRights, error) {
	if metaPair == nil {
		return nil, fmt.Errorf("no zettel list")
	}
	if errSym := sexp.CheckSymbol(metaPair.Car(), "list"); errSym != nil {

		return api.InvalidZID, fmt.Errorf("invalid zettel ID: %v", val)
	}
	return zid, nil
}

// QueryAggregate returns a aggregate as a result of a query.
// It is most often used in a query with an action, where the action is either
// a metadata key of type Word, WordSet, or TagSet.
// a metadata key of type Word or of type TagSet.
func (c *Client) QueryAggregate(ctx context.Context, query string) (api.Aggregate, error) {
	lines, err := c.QueryZettel(ctx, query)
	if err != nil {
		return nil, err
	}
	if len(lines) == 0 {
		return nil, nil

					agg[key] = append(agg[key], zid)
				}
			}
		}
	}
	return agg, nil
}

// TagZettel returns the tag zettel of a given tag.
//
// This method only works if c.AllowRedirect(true) was called.
func (c *Client) TagZettel(ctx context.Context, tag string) (api.ZettelID, error) {
	return c.fetchTagOrRoleZettel(ctx, api.QueryKeyTag, tag)
}

// RoleZettel returns the tag zettel of a given tag.
//
// This method only works if c.AllowRedirect(true) was called.
func (c *Client) RoleZettel(ctx context.Context, role string) (api.ZettelID, error) {
	return c.fetchTagOrRoleZettel(ctx, api.QueryKeyRole, role)
}

func (c *Client) fetchTagOrRoleZettel(ctx context.Context, key, val string) (api.ZettelID, error) {
	if c.client.CheckRedirect == nil {
		panic("client does not allow to track redirect")
	}
	ub := c.NewURLBuilder('z').AppendKVQuery(key, val)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil)
	if err != nil {
		return api.InvalidZID, err
	}
	defer resp.Body.Close()
	data, err := io.ReadAll(resp.Body)
	if err != nil {
		return api.InvalidZID, err
	}

	switch resp.StatusCode {
	case http.StatusNotFound:
		return "", nil
	case http.StatusFound:
		zid := api.ZettelID(data)
		if zid.IsValid() {
			return zid, nil
		}
		return api.InvalidZID, nil
	default:
		return api.InvalidZID, statusToError(resp)
	}
}

// GetZettel returns a zettel as a string.
func (c *Client) GetZettel(ctx context.Context, zid api.ZettelID, part string) ([]byte, error) {
	ub := c.newURLBuilder('z').SetZid(zid)
	ub := c.NewURLBuilder('z').SetZid(zid)
	if part != "" && part != api.PartContent {
		ub.AppendKVQuery(api.QueryKeyPart, part)
	}
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil, nil)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()
	data, err := io.ReadAll(resp.Body)
	switch resp.StatusCode {
	case http.StatusOK:
	case http.StatusNoContent:
		return nil, nil
	default:
		return nil, statusToError(resp)
	}
	return data, err
}

// GetZettelData returns a zettel as a struct of its parts.
func (c *Client) GetZettelData(ctx context.Context, zid api.ZettelID) (api.ZettelData, error) {
	ub := c.newURLBuilder('z').SetZid(zid)
	ub := c.NewURLBuilder('z').SetZid(zid)
	ub.AppendKVQuery(api.QueryKeyEncoding, api.EncodingData)
	ub.AppendKVQuery(api.QueryKeyPart, api.PartZettel)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil, nil)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil)
	if err == nil {
		defer resp.Body.Close()
		if resp.StatusCode != http.StatusOK {
			return api.ZettelData{}, statusToError(resp)
		}
		rdr := sxreader.MakeReader(resp.Body)
		obj, err2 := rdr.Read()

// GetEvaluatedZettel return an evaluated zettel in a defined encoding.
func (c *Client) GetEvaluatedZettel(ctx context.Context, zid api.ZettelID, enc api.EncodingEnum) ([]byte, error) {
	return c.getZettelString(ctx, zid, enc, false)
}

func (c *Client) getZettelString(ctx context.Context, zid api.ZettelID, enc api.EncodingEnum, parseOnly bool) ([]byte, error) {
	ub := c.newURLBuilder('z').SetZid(zid)
	ub := c.NewURLBuilder('z').SetZid(zid)
	ub.AppendKVQuery(api.QueryKeyEncoding, enc.String())
	ub.AppendKVQuery(api.QueryKeyPart, api.PartContent)
	if parseOnly {
		ub.AppendKVQuery(api.QueryKeyParseOnly, "")
	}
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil, nil)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()
	switch resp.StatusCode {
	case http.StatusOK:
	case http.StatusNoContent:
	default:
		return nil, statusToError(resp)
	}
	return io.ReadAll(resp.Body)
}

// GetParsedSz returns an parsed zettel as a Sexpr-decoded data structure.
func (c *Client) GetParsedSz(ctx context.Context, zid api.ZettelID, part string, sf sx.SymbolFactory) (sx.Object, error) {
	return c.getSz(ctx, zid, part, true, sf)
func (c *Client) GetParsedSz(ctx context.Context, zid api.ZettelID, part string) (sx.Object, error) {
	return c.getSz(ctx, zid, part, true)
}

// GetEvaluatedSz returns an evaluated zettel as a Sexpr-decoded data structure.
func (c *Client) GetEvaluatedSz(ctx context.Context, zid api.ZettelID, part string, sf sx.SymbolFactory) (sx.Object, error) {
	return c.getSz(ctx, zid, part, false, sf)
func (c *Client) GetEvaluatedSz(ctx context.Context, zid api.ZettelID, part string) (sx.Object, error) {
	return c.getSz(ctx, zid, part, false)
}

func (c *Client) getSz(ctx context.Context, zid api.ZettelID, part string, parseOnly bool, sf sx.SymbolFactory) (sx.Object, error) {
	ub := c.newURLBuilder('z').SetZid(zid)
func (c *Client) getSz(ctx context.Context, zid api.ZettelID, part string, parseOnly bool) (sx.Object, error) {
	ub := c.NewURLBuilder('z').SetZid(zid)
	ub.AppendKVQuery(api.QueryKeyEncoding, api.EncodingSz)
	if part != "" {
		ub.AppendKVQuery(api.QueryKeyPart, part)
	}
	if parseOnly {
		ub.AppendKVQuery(api.QueryKeyParseOnly, "")
	}
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil, nil)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusOK {
		return nil, statusToError(resp)
	}
	return sxreader.MakeReader(bufio.NewReaderSize(resp.Body, 8), sxreader.WithSymbolFactory(sf)).Read()
	return sxreader.MakeReader(bufio.NewReaderSize(resp.Body, 8)).Read()
}

// GetMetaData returns the metadata of a zettel.
func (c *Client) GetMetaData(ctx context.Context, zid api.ZettelID) (api.MetaRights, error) {
	ub := c.newURLBuilder('z').SetZid(zid)
	ub := c.NewURLBuilder('z').SetZid(zid)
	ub.AppendKVQuery(api.QueryKeyEncoding, api.EncodingData)
	ub.AppendKVQuery(api.QueryKeyPart, api.PartMeta)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil, nil)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil)
	if err != nil {
		return api.MetaRights{}, err
	}
	defer resp.Body.Close()
	rdr := sxreader.MakeReader(resp.Body)
	obj, err := rdr.Read()
	if resp.StatusCode != http.StatusOK {

		Meta:   meta,
		Rights: rights,
	}, nil
}

// UpdateZettel updates an existing zettel.
func (c *Client) UpdateZettel(ctx context.Context, zid api.ZettelID, data []byte) error {
	ub := c.newURLBuilder('z').SetZid(zid)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodPut, ub, bytes.NewBuffer(data), nil)
	ub := c.NewURLBuilder('z').SetZid(zid)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodPut, ub, bytes.NewBuffer(data))
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusNoContent {
		return statusToError(resp)
	}
	return nil
}

// UpdateZettelData updates an existing zettel.
func (c *Client) UpdateZettelData(ctx context.Context, zid api.ZettelID, data api.ZettelData) error {
	var buf bytes.Buffer
	if _, err := sx.Print(&buf, sexp.EncodeZettel(data)); err != nil {
		return err
	}
	ub := c.newURLBuilder('z').SetZid(zid).AppendKVQuery(api.QueryKeyEncoding, api.EncodingData)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodPut, ub, &buf, nil)
	ub := c.NewURLBuilder('z').SetZid(zid).AppendKVQuery(api.QueryKeyEncoding, api.EncodingData)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodPut, ub, &buf)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusNoContent {
		return statusToError(resp)
	}
	return nil
}

// RenameZettel renames a zettel.
func (c *Client) RenameZettel(ctx context.Context, oldZid, newZid api.ZettelID) error {
	ub := c.newURLBuilder('z').SetZid(oldZid)
	h := http.Header{
		api.HeaderDestination: {c.newURLBuilder('z').SetZid(newZid).String()},
	}
	resp, err := c.buildAndExecuteRequest(ctx, api.MethodMove, ub, nil, h)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusNoContent {
		return statusToError(resp)
	}
	return nil
}

// DeleteZettel deletes a zettel with the given identifier.
func (c *Client) DeleteZettel(ctx context.Context, zid api.ZettelID) error {
	ub := c.newURLBuilder('z').SetZid(zid)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodDelete, ub, nil, nil)
	ub := c.NewURLBuilder('z').SetZid(zid)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodDelete, ub, nil)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusNoContent {
		return statusToError(resp)
	}
	return nil
}

// ExecuteCommand will execute a given command at the Zettelstore.
func (c *Client) ExecuteCommand(ctx context.Context, command api.Command) error {
	ub := c.newURLBuilder('x').AppendKVQuery(api.QueryKeyCommand, string(command))
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodPost, ub, nil, nil)
	ub := c.NewURLBuilder('x').AppendKVQuery(api.QueryKeyCommand, string(command))
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodPost, ub, nil)
	if err != nil {
		return err
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusNoContent {
		return statusToError(resp)
	}
	return nil
}

// GetVersionInfo returns version information..
// GetVersionInfo returns version information.
func (c *Client) GetVersionInfo(ctx context.Context) (VersionInfo, error) {
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, c.newURLBuilder('x'), nil, nil)
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, c.NewURLBuilder('x'), nil)
	if err != nil {
		return VersionInfo{}, err
	}
	defer resp.Body.Close()
	if resp.StatusCode != http.StatusOK {
		return VersionInfo{}, statusToError(resp)
	}
	rdr := sxreader.MakeReader(resp.Body)
	obj, err := rdr.Read()
	if err == nil {
		if vals, errVals := sexp.ParseList(obj, "iiiss"); errVals == nil {
			return VersionInfo{
				Major: int(vals[0].(sx.Int64)),
				Minor: int(vals[1].(sx.Int64)),
				Patch: int(vals[2].(sx.Int64)),
				Info:  vals[3].(sx.String).String(),
				Hash:  vals[4].(sx.String).String(),
				Info:  vals[3].(sx.String).GetValue(),
				Hash:  vals[4].(sx.String).GetValue(),
			}, nil
		}
	}
	return VersionInfo{}, err
}

// VersionInfo contains version information.
type VersionInfo struct {
	Major int
	Minor int
	Patch int
	Info  string
	Hash  string
}

// GetApplicationZid returns the zettel identifier used to configure client
// application with the given name.
func (c *Client) GetApplicationZid(ctx context.Context, appname string) (api.ZettelID, error) {
	mr, err := c.GetMetaData(ctx, api.ZidAppDirectory)
	if err != nil {
		return api.InvalidZID, err
	}
	key := appname + "-zid"
	val, found := mr.Meta[key]
	if !found {
		return api.InvalidZID, fmt.Errorf("no application registered: %v", appname)
	}
	if zid := api.ZettelID(val); zid.IsValid() {
		return zid, nil
	}
	return api.InvalidZID, fmt.Errorf("invalid identifier for application %v: %v", appname, val)
}

// Get executes a GET request to the given URL and returns the read data.
func (c *Client) Get(ctx context.Context, ub *api.URLBuilder) ([]byte, error) {
	resp, err := c.buildAndExecuteRequest(ctx, http.MethodGet, ub, nil)
	if err != nil {
		return nil, err
	}
	defer resp.Body.Close()
	switch resp.StatusCode {
	case http.StatusOK:
	case http.StatusNoContent:
		return nil, nil
	default:
		return nil, statusToError(resp)
	}
	data, err := io.ReadAll(resp.Body)
	return data, err
}

//-----------------------------------------------------------------------------
// Copyright (c) 2022-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2022-present Detlef Stern
//-----------------------------------------------------------------------------

package client_test

import (
	"context"
	"flag"
	"net/http"
	"net/url"
	"testing"

	"zettelstore.de/client.fossil/api"
	"t73f.de/r/zsc/api"
	"zettelstore.de/client.fossil/client"
	"zettelstore.de/client.fossil/sz"
	"t73f.de/r/zsc/client"
	"zettelstore.de/sx.fossil"
)

func TestZettelList(t *testing.T) {
	c := getClient()
	_, err := c.QueryZettel(context.Background(), "")
	if err != nil {
		t.Error(err)

		}
		return
	}
}

func TestGetSzZettel(t *testing.T) {
	c := getClient()
	sf := sx.MakeMappedFactory()
	var zetSyms sz.ZettelSymbols
	zetSyms.InitializeZettelSymbols(sf)
	value, err := c.GetEvaluatedSz(context.Background(), api.ZidDefaultHome, api.PartContent, sf)
	value, err := c.GetEvaluatedSz(context.Background(), api.ZidDefaultHome, api.PartContent)
	if err != nil {
		t.Error(err)
		return
	}
	if value.IsNil() {
		t.Error("No data")
	}

module zettelstore.de/client.fossil
module t73f.de/r/zsc

go 1.20
go 1.23

require zettelstore.de/sx.fossil v0.0.0-20230727172325-adec5a7ba284
require (
	t73f.de/r/sx v0.0.0-20240814083626-4df0ec6454b5
	t73f.de/r/sxwebs v0.0.0-20240814085618-5b4b5c496c94
	t73f.de/r/webs v0.0.0-20240814085020-19dac746d568
)

zettelstore.de/sx.fossil v0.0.0-20230727172325-adec5a7ba284 h1:26xwZWEjdyL3wObczc/PKugv0EY6mgSH5NUe5kYFCt4=
zettelstore.de/sx.fossil v0.0.0-20230727172325-adec5a7ba284/go.mod h1:nsWXVrQG8RNKtoXzEMrWXNMdnpfIDU6Hb0pk56KpVKE=
t73f.de/r/sx v0.0.0-20240814083626-4df0ec6454b5 h1:ug4hohM6pK28M8Uo0o3+XvjBure2wfEtuCnHVIdqBZY=
t73f.de/r/sx v0.0.0-20240814083626-4df0ec6454b5/go.mod h1:VRvsWoBErPKvMieDMMk1hsh1tb9sA4ijEQWGw/TbtQ0=
t73f.de/r/sxwebs v0.0.0-20240814085618-5b4b5c496c94 h1:gLneaEyYotvcY/dDznzdcSXK1RqsJVi2AfeYDc1iVwM=
t73f.de/r/sxwebs v0.0.0-20240814085618-5b4b5c496c94/go.mod h1:83W3QFkmrniIKv6R+Xq+imvbSolhoutTnNhW0ErJoco=
t73f.de/r/webs v0.0.0-20240814085020-19dac746d568 h1:Pa+vO2r++qhcShv0p7t/gIrJ1DHPMn4gopEXLxDmoRg=
t73f.de/r/webs v0.0.0-20240814085020-19dac746d568/go.mod h1:NSoOON8be62MfQZzlCApK27Jt2zhIa6Vrmo9RJ4tOnQ=

//-----------------------------------------------------------------------------
// Copyright (c) 2022-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2022-present Detlef Stern
//-----------------------------------------------------------------------------

package input

import (
	"html"
	"unicode"
)

// ScanEntity scans either a named or a numbered entity and returns it as a string.
//
// For numbered entities (like { or ģ) html.UnescapeString returns
// sometimes other values as expected, if the number is not well-formed. This
// may happen because of some strange HTML parsing rules. But these do not
// apply to Zettelmarkup. Therefore, I parse the number here in the code.
func (inp *Input) ScanEntity() (res string, success bool) {
	if inp.Ch != '&' {
		return "", false
	}
	pos := inp.Pos
	inp.Next()
	if inp.Ch == '#' {
		inp.Next()
		if inp.Ch == 'x' || inp.Ch == 'X' {
			return inp.scanEntityBase16()
		}
		return inp.scanEntityBase10()
	}
	return inp.scanEntityNamed(pos)
}

func (inp *Input) scanEntityBase16() (string, bool) {
	inp.Next()
	if inp.Ch == ';' {
		return "", false
	}
	code := 0
	for {
		switch ch := inp.Ch; ch {
		case ';':
			inp.Next()
			if r := rune(code); isValidEntity(r) {
				return string(r), true
			}
			return "", false
		case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
			code = 16*code + int(ch-'0')
		case 'a', 'b', 'c', 'd', 'e', 'f':
			code = 16*code + int(ch-'a'+10)
		case 'A', 'B', 'C', 'D', 'E', 'F':
			code = 16*code + int(ch-'A'+10)
		default:
			return "", false
		}
		if code > unicode.MaxRune {
			return "", false
		}
		inp.Next()
	}
}

func (inp *Input) scanEntityBase10() (string, bool) {
	// Base 10 code
	if inp.Ch == ';' {
		return "", false
	}
	code := 0
	for {
		switch ch := inp.Ch; ch {
		case ';':
			inp.Next()
			if r := rune(code); isValidEntity(r) {
				return string(r), true
			}
			return "", false
		case '0', '1', '2', '3', '4', '5', '6', '7', '8', '9':
			code = 10*code + int(ch-'0')
		default:
			return "", false
		}
		if code > unicode.MaxRune {
			return "", false
		}
		inp.Next()
	}
}
func (inp *Input) scanEntityNamed(pos int) (string, bool) {
	for {
		switch inp.Ch {
		case EOS, '\n', '\r', '&':
			return "", false
		case ';':
			inp.Next()
			es := string(inp.Src[pos:inp.Pos])
			ues := html.UnescapeString(es)
			if es == ues {
				return "", false
			}
			return ues, true
		default:
			inp.Next()
		}
	}
}

// isValidEntity checks if the given code is valid for an entity.
//
// According to https://html.spec.whatwg.org/multipage/syntax.html#character-references
// ""The numeric character reference forms described above are allowed to reference any code point
// excluding U+000D CR, noncharacters, and controls other than ASCII whitespace.""
func isValidEntity(r rune) bool {
	// No C0 control and no "code point in the range U+007F DELETE to U+009F APPLICATION PROGRAM COMMAND, inclusive."
	if r < ' ' || ('\u007f' <= r && r <= '\u009f') {
		return false
	}

	// If below any noncharacter code point, return true
	//
	// See: https://infra.spec.whatwg.org/#noncharacter
	if r < '\ufdd0' {
		return true
	}

	// First range of noncharacter code points: "(...) in the range U+FDD0 to U+FDEF, inclusive"
	if r <= '\ufdef' {
		return false
	}

	// Other noncharacter code points:
	switch r {
	case '\uFFFE', '\uFFFF',
		'\U0001FFFE', '\U0001FFFF',
		'\U0002FFFE', '\U0002FFFF',
		'\U0003FFFE', '\U0003FFFF',
		'\U0004FFFE', '\U0004FFFF',
		'\U0005FFFE', '\U0005FFFF',
		'\U0006FFFE', '\U0006FFFF',
		'\U0007FFFE', '\U0007FFFF',
		'\U0008FFFE', '\U0008FFFF',
		'\U0009FFFE', '\U0009FFFF',
		'\U000AFFFE', '\U000AFFFF',
		'\U000BFFFE', '\U000BFFFF',
		'\U000CFFFE', '\U000CFFFF',
		'\U000DFFFE', '\U000DFFFF',
		'\U000EFFFE', '\U000EFFFF',
		'\U000FFFFE', '\U000FFFFF',
		'\U0010FFFE', '\U0010FFFF':
		return false
	}
	return true
}

//-----------------------------------------------------------------------------
// Copyright (c) 2020-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2020-present Detlef Stern
//-----------------------------------------------------------------------------

package input_test

import (
	"testing"

	"t73f.de/r/zsc/input"
)

func TestScanEntity(t *testing.T) {
	t.Parallel()
	var testcases = []struct {
		text string
		exp  string
	}{
		{"", ""},
		{"a", ""},
		{"&", "&"},
		{"!", "!"},
		{"3", "3"},
		{""", "\""},
	}
	for id, tc := range testcases {
		inp := input.NewInput([]byte(tc.text))
		got, ok := inp.ScanEntity()
		if !ok {
			if tc.exp != "" {
				t.Errorf("ID=%d, text=%q: expected error, but got %q", id, tc.text, got)
			}
			if inp.Pos != 0 {
				t.Errorf("ID=%d, text=%q: input position advances to %d", id, tc.text, inp.Pos)
			}
			continue
		}
		if tc.exp != got {
			t.Errorf("ID=%d, text=%q: expected %q, but got %q", id, tc.text, tc.exp, got)
		}
	}
}

func TestScanIllegalEntity(t *testing.T) {
	t.Parallel()
	testcases := []string{"", "a", "& Input →", "	", ""}
	for i, tc := range testcases {
		inp := input.NewInput([]byte(tc))
		got, ok := inp.ScanEntity()
		if ok {
			t.Errorf("%d: scanning %q was unexpected successful, got %q", i, tc, got)
			continue
		}
	}
}

//-----------------------------------------------------------------------------
// Copyright (c) 2020-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2020-present Detlef Stern
//-----------------------------------------------------------------------------

// Package input provides an abstraction for data to be read.
package input

import "unicode/utf8"

// Input is an abstract input source
type Input struct {
	// Read-only, will never change
	Src []byte // The source string

	// Read-only, will change
	Ch      rune // current character
	Pos     int  // character position in src
	readPos int  // reading position (position after current character)
}

// NewInput creates a new input source.
func NewInput(src []byte) *Input {
	inp := &Input{Src: src}
	inp.Next()
	return inp
}

// EOS = End of source
const EOS = rune(-1)

// Next reads the next rune into inp.Ch and returns it too.
func (inp *Input) Next() rune {
	if inp.readPos >= len(inp.Src) {
		inp.Pos = len(inp.Src)
		inp.Ch = EOS
		return EOS
	}
	inp.Pos = inp.readPos
	r, w := rune(inp.Src[inp.readPos]), 1
	if r >= utf8.RuneSelf {
		r, w = utf8.DecodeRune(inp.Src[inp.readPos:])
	}
	inp.readPos += w
	inp.Ch = r
	return r
}

// Peek returns the rune following the most recently read rune without
// advancing. If end-of-source was already found peek returns EOS.
func (inp *Input) Peek() rune {
	return inp.PeekN(0)
}

// PeekN returns the n-th rune after the most recently read rune without
// advancing. If end-of-source was already found peek returns EOS.
func (inp *Input) PeekN(n int) rune {
	pos := inp.readPos + n
	if pos < len(inp.Src) {
		r := rune(inp.Src[pos])
		if r >= utf8.RuneSelf {
			r, _ = utf8.DecodeRune(inp.Src[pos:])
		}
		if r == '\t' {
			return ' '
		}
		return r
	}
	return EOS
}

// Accept checks if the given string is a prefix of the text to be parsed.
// If successful, advance position and current character.
// String must only contain bytes < 128.
// If not successful, everything remains as it is.
func (inp *Input) Accept(s string) bool {
	pos := inp.Pos
	remaining := len(inp.Src) - pos
	if s == "" || len(s) > remaining {
		return false
	}
	// According to internal documentation of bytes.Equal, the string() will not allocate any memory.
	if readPos := pos + len(s); s == string(inp.Src[pos:readPos]) {
		inp.readPos = readPos
		inp.Next()
		return true
	}
	return false
}

// IsEOLEOS returns true if char is either EOS or EOL.
func IsEOLEOS(ch rune) bool { return ch == EOS || ch == '\n' || ch == '\r' }

// EatEOL transforms both "\r" and "\r\n" into "\n".
func (inp *Input) EatEOL() {
	switch inp.Ch {
	case '\r':
		if inp.Peek() == '\n' {
			inp.Next()
		}
		inp.Ch = '\n'
		inp.Next()
	case '\n':
		inp.Next()
	}
}

// SetPos allows to reset the read position.
func (inp *Input) SetPos(pos int) {
	if inp.Pos != pos {
		inp.readPos = pos
		inp.Next()
	}
}

// SkipSpace reads while the current character is not a space character.
func (inp *Input) SkipSpace() {
	for ch := inp.Ch; IsSpace(ch); {
		ch = inp.Next()
	}
}

// SkipToEOL reads until the next end-of-line.
func (inp *Input) SkipToEOL() {
	for {
		switch inp.Ch {
		case EOS, '\n', '\r':
			return
		}
		inp.Next()
	}
}

// ScanLineContent reads the reaining input stream and interprets it as lines of text.
func (inp *Input) ScanLineContent() []byte {
	result := make([]byte, 0, len(inp.Src)-inp.Pos+1)
	for {
		inp.EatEOL()
		posL := inp.Pos
		if inp.Ch == EOS {
			return result
		}
		inp.SkipToEOL()
		if len(result) > 0 {
			result = append(result, '\n')
		}
		result = append(result, inp.Src[posL:inp.Pos]...)
	}
}

//-----------------------------------------------------------------------------
// Copyright (c) 2020-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2020-present Detlef Stern
//-----------------------------------------------------------------------------

// Package input_test provides some unit-tests for reading data.
package input_test

import (
	"testing"

	"t73f.de/r/zsc/input"
)

func TestEatEOL(t *testing.T) {
	t.Parallel()
	inp := input.NewInput(nil)
	inp.EatEOL()
	if inp.Ch != input.EOS {
		t.Errorf("No EOS found: %q", inp.Ch)
	}
	if inp.Pos != 0 {
		t.Errorf("Pos != 0: %d", inp.Pos)
	}

	inp = input.NewInput([]byte("ABC"))
	if inp.Ch != 'A' {
		t.Errorf("First ch != 'A', got %q", inp.Ch)
	}
	inp.EatEOL()
	if inp.Ch != 'A' {
		t.Errorf("First ch != 'A', got %q", inp.Ch)
	}
}

func TestAccept(t *testing.T) {
	t.Parallel()
	testcases := []struct {
		accept string
		src    string
		acc    bool
		exp    rune
	}{
		{"", "", false, input.EOS},
		{"AB", "abc", false, 'a'},
		{"AB", "ABC", true, 'C'},
		{"AB", "AB", true, input.EOS},
		{"AB", "A", false, 'A'},
	}
	for i, tc := range testcases {
		inp := input.NewInput([]byte(tc.src))
		acc := inp.Accept(tc.accept)
		if acc != tc.acc {
			t.Errorf("%d: %q.Accept(%q) == %v, but got %v", i, tc.src, tc.accept, tc.acc, acc)
		}
		if got := inp.Ch; tc.exp != got {
			t.Errorf("%d: %q.Accept(%q) should result in run %v, but got %v", i, tc.src, tc.accept, tc.exp, got)
		}
	}
}

//-----------------------------------------------------------------------------
// Copyright (c) 2020-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2020-present Detlef Stern
//-----------------------------------------------------------------------------

package input

import "unicode"

// IsSpace returns true if rune is a whitespace.
func IsSpace(ch rune) bool {
	switch ch {
	case ' ', '\t':
		return true
	case '\n', '\r', EOS:
		return false
	}
	return unicode.IsSpace(ch)
}

// IsSpace returns true if current character is a whitespace.
func (inp *Input) IsSpace() bool { return IsSpace(inp.Ch) }

//-----------------------------------------------------------------------------
// Copyright (c) 2022-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2022-present Detlef Stern
//-----------------------------------------------------------------------------

package maps

import "sort"

func Keys[T any](m map[string]T) []string {

//-----------------------------------------------------------------------------
// Copyright (c) 2022-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2022-present Detlef Stern
//-----------------------------------------------------------------------------

package maps_test

import (
	"testing"

	"zettelstore.de/client.fossil/maps"
	"t73f.de/r/zsc/maps"
)

func isSorted(seq []string) bool {
	for i := 1; i < len(seq); i++ {
		if seq[i] < seq[i-1] {
			return false
		}

//-----------------------------------------------------------------------------
// Copyright (c) 2023-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2023-present Detlef Stern
//-----------------------------------------------------------------------------

// Package sexp contains helper function to work with s-expression in an alien
// environment.
package sexp

import (
	"errors"
	"fmt"
	"sort"

	"zettelstore.de/client.fossil/api"
	"zettelstore.de/sx.fossil"
	"t73f.de/r/sx"
	"t73f.de/r/zsc/api"
)

// EncodeZettel transforms zettel data into a sx object.
func EncodeZettel(zettel api.ZettelData) sx.Object {
	sf := sx.MakeMappedFactory()
	return sx.MakeList(
		sf.MustMake("zettel"),
		meta2sz(zettel.Meta, sf),
		sx.MakeList(sf.MustMake("rights"), sx.Int64(int64(zettel.Rights))),
		sx.MakeList(sf.MustMake("encoding"), sx.MakeString(zettel.Encoding)),
		sx.MakeList(sf.MustMake("content"), sx.MakeString(zettel.Content)),
		sx.MakeSymbol("zettel"),
		meta2sz(zettel.Meta),
		sx.MakeList(sx.MakeSymbol("rights"), sx.Int64(int64(zettel.Rights))),
		sx.MakeList(sx.MakeSymbol("encoding"), sx.MakeString(zettel.Encoding)),
		sx.MakeList(sx.MakeSymbol("content"), sx.MakeString(zettel.Content)),
	)
}

func ParseZettel(obj sx.Object) (api.ZettelData, error) {
	vals, err := ParseList(obj, "ypppp")
	if err != nil {
		return api.ZettelData{}, err

	if errSym := CheckSymbol(contentVals[0], "content"); errSym != nil {
		return api.ZettelData{}, errSym
	}

	return api.ZettelData{
		Meta:     meta,
		Rights:   rights,
		Encoding: encVals[1].(sx.String).String(),
		Content:  contentVals[1].(sx.String).String(),
		Encoding: encVals[1].(sx.String).GetValue(),
		Content:  contentVals[1].(sx.String).GetValue(),
	}, nil
}

// EncodeMetaRights translates metadata/rights into a sx object.
func EncodeMetaRights(mr api.MetaRights) *sx.Pair {
	sf := sx.MakeMappedFactory()
	return sx.MakeList(
		sf.MustMake("list"),
		meta2sz(mr.Meta, sf),
		sx.MakeList(sf.MustMake("rights"), sx.Int64(int64(mr.Rights))),
		sx.SymbolList,
		meta2sz(mr.Meta),
		sx.MakeList(sx.MakeSymbol("rights"), sx.Int64(int64(mr.Rights))),
	)
}

func meta2sz(m api.ZettelMeta, sf sx.SymbolFactory) sx.Object {
	result := sx.Nil().Cons(sf.MustMake("meta"))
	curr := result
func meta2sz(m api.ZettelMeta) sx.Object {
	var result sx.ListBuilder
	result.Add(sx.MakeSymbol("meta"))
	keys := make([]string, 0, len(m))
	for k := range m {
		keys = append(keys, k)
	}
	sort.Strings(keys)
	for _, k := range keys {
		val := sx.MakeList(sf.MustMake(k), sx.MakeString(m[k]))
		curr = curr.AppendBang(val)
		val := sx.MakeList(sx.MakeSymbol(k), sx.MakeString(m[k]))
		result.Add(val)
	}
	return result
	return result.List()
}

// ParseMeta translates the given list to metadata.
func ParseMeta(pair *sx.Pair) (api.ZettelMeta, error) {
	if err := CheckSymbol(pair.Car(), "meta"); err != nil {
		return nil, err
	}
	res := api.ZettelMeta{}
	for node := pair.Tail(); node != nil; node = node.Tail() {
		mVals, err := ParseList(node.Car(), "ys")
		if err != nil {
			return nil, err
		}
		res[mVals[0].(*sx.Symbol).Name()] = mVals[1].(sx.String).String()
		res[(mVals[0].(*sx.Symbol)).GetValue()] = mVals[1].(sx.String).GetValue()
	}
	return res, nil
}

// ParseRights returns the rights values of the given object.
func ParseRights(obj sx.Object) (api.ZettelRights, error) {
	rVals, err := ParseList(obj, "yi")

	if i64 < 0 && i64 >= int64(api.ZettelMaxRight) {
		return api.ZettelMaxRight, fmt.Errorf("invalid zettel right value: %v", i64)
	}
	return api.ZettelRights(i64), nil
}

// ParseList parses the given object as a proper list, based on a type specification.
func ParseList(obj sx.Object, spec string) ([]sx.Object, error) {
func ParseList(obj sx.Object, spec string) (sx.Vector, error) {
	pair, isPair := sx.GetPair(obj)
	if !isPair {
		return nil, fmt.Errorf("not a list: %T/%v", obj, obj)
	}
	if pair == nil {
		if spec == "" {
			return nil, nil
		}
		return nil, ErrElementsMissing
	}

	result := make([]sx.Object, 0, len(spec))
	result := make(sx.Vector, 0, len(spec))
	node, i := pair, 0
	for ; node != nil; i++ {
		if i >= len(spec) {
			return nil, ErrNoSpec
		}
		var val sx.Object
		var ok bool
		car := node.Car()
		switch spec[i] {
		case 'b':
			val, ok = sx.GetBoolean(car)
			val, ok = sx.MakeBoolean(!sx.IsNil(car)), true
		case 'i':
			val, ok = car.(sx.Int64)
		case 'o':
			val, ok = car, true
		case 'p':
			val, ok = sx.GetPair(car)
		case 's':

// CheckSymbol ensures that the given object is a symbol with the given name.
func CheckSymbol(obj sx.Object, name string) error {
	sym, isSymbol := sx.GetSymbol(obj)
	if !isSymbol {
		return fmt.Errorf("object %v/%T is not a symbol", obj, obj)
	}
	if got := sym.Name(); got != name {
	if got := sym.GetValue(); got != name {
		return fmt.Errorf("symbol %q expected, but got: %q", name, got)
	}
	return nil
}

//-----------------------------------------------------------------------------
// Copyright (c) 2023-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2023-present Detlef Stern
//-----------------------------------------------------------------------------

package sexp_test

import (
	"testing"

	"zettelstore.de/client.fossil/sexp"
	"zettelstore.de/sx.fossil"
	"t73f.de/r/sx"
	"t73f.de/r/zsc/sexp"
)

func TestParseObject(t *testing.T) {
	if elems, err := sexp.ParseList(sx.MakeString("a"), "s"); err == nil {
		t.Error("expected an error, but got: ", elems)
	}
	if elems, err := sexp.ParseList(sx.Nil(), ""); err != nil {

	if elems, err := sexp.ParseList(sx.MakeList(sx.MakeString("a")), "ss"); err == nil {
		t.Error("expected error, but got: ", elems)
	}
	if elems, err := sexp.ParseList(sx.MakeList(sx.MakeString("a")), ""); err == nil {
		t.Error("expected error, but got: ", elems)
	}
	if elems, err := sexp.ParseList(sx.MakeList(sx.MakeString("a")), "b"); err == nil {
		t.Error("expected error, but got: ", elems)
	if _, err := sexp.ParseList(sx.MakeList(sx.MakeString("a")), "b"); err != nil {
		t.Error("expected [1], but got error: ", err)
	}
	if elems, err := sexp.ParseList(sx.Cons(sx.Nil(), sx.MakeString("a")), "ps"); err == nil {
		t.Error("expected error, but got: ", elems)
	}

	if elems, err := sexp.ParseList(sx.MakeList(sx.MakeString("a")), "s"); err != nil {
		t.Error(err)

//-----------------------------------------------------------------------------
// Copyright (c) 2024-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2024-present Detlef Stern
//-----------------------------------------------------------------------------

package shtml

import "t73f.de/r/sx"

// Symbols for HTML header tags
var (
	SymBody   = sx.MakeSymbol("body")
	SymHead   = sx.MakeSymbol("head")
	SymHtml   = sx.MakeSymbol("html")
	SymMeta   = sx.MakeSymbol("meta")
	SymScript = sx.MakeSymbol("script")
	SymTitle  = sx.MakeSymbol("title")
)

// Symbols for HTML body tags
var (
	SymA          = sx.MakeSymbol("a")
	SymASIDE      = sx.MakeSymbol("aside")
	symBLOCKQUOTE = sx.MakeSymbol("blockquote")
	symBR         = sx.MakeSymbol("br")
	symCITE       = sx.MakeSymbol("cite")
	symCODE       = sx.MakeSymbol("code")
	symDD         = sx.MakeSymbol("dd")
	symDEL        = sx.MakeSymbol("del")
	SymDIV        = sx.MakeSymbol("div")
	symDL         = sx.MakeSymbol("dl")
	symDT         = sx.MakeSymbol("dt")
	symEM         = sx.MakeSymbol("em")
	SymEMBED      = sx.MakeSymbol("embed")
	SymFIGURE     = sx.MakeSymbol("figure")
	SymH1         = sx.MakeSymbol("h1")
	SymH2         = sx.MakeSymbol("h2")
	SymHR         = sx.MakeSymbol("hr")
	SymIMG        = sx.MakeSymbol("img")
	symINS        = sx.MakeSymbol("ins")
	symKBD        = sx.MakeSymbol("kbd")
	SymLI         = sx.MakeSymbol("li")
	symMARK       = sx.MakeSymbol("mark")
	SymOL         = sx.MakeSymbol("ol")
	SymP          = sx.MakeSymbol("p")
	symPRE        = sx.MakeSymbol("pre")
	symSAMP       = sx.MakeSymbol("samp")
	SymSPAN       = sx.MakeSymbol("span")
	SymSTRONG     = sx.MakeSymbol("strong")
	symSUB        = sx.MakeSymbol("sub")
	symSUP        = sx.MakeSymbol("sup")
	symTABLE      = sx.MakeSymbol("table")
	symTBODY      = sx.MakeSymbol("tbody")
	symTHEAD      = sx.MakeSymbol("thead")
	symTD         = sx.MakeSymbol("td")
	symTH         = sx.MakeSymbol("th")
	symTR         = sx.MakeSymbol("tr")
	SymUL         = sx.MakeSymbol("ul")
)

// Symbols for HTML attribute keys
var (
	symAttrAlt    = sx.MakeSymbol("alt")
	SymAttrClass  = sx.MakeSymbol("class")
	SymAttrHref   = sx.MakeSymbol("href")
	SymAttrId     = sx.MakeSymbol("id")
	SymAttrLang   = sx.MakeSymbol("lang")
	SymAttrOpen   = sx.MakeSymbol("open")
	SymAttrRel    = sx.MakeSymbol("rel")
	SymAttrRole   = sx.MakeSymbol("role")
	SymAttrSrc    = sx.MakeSymbol("src")
	SymAttrTarget = sx.MakeSymbol("target")
	SymAttrTitle  = sx.MakeSymbol("title")
	SymAttrType   = sx.MakeSymbol("type")
	SymAttrValue  = sx.MakeSymbol("value")
)

//-----------------------------------------------------------------------------
// Copyright (c) 2023-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2023-present Detlef Stern
//-----------------------------------------------------------------------------

package shtml

import (
	"strings"

	"t73f.de/r/zsc/api"
)

// LangStack is a stack to store the nesting of "lang" attribute values.
// It is used to generate typographically correct quotes.
type LangStack []string

// NewLangStack creates a new language stack.
func NewLangStack(lang string) LangStack {
	ls := make([]string, 1, 16)
	ls[0] = lang
	return ls
}

// Reset restores the language stack to its initial value.
func (ls *LangStack) Reset() {
	*ls = (*ls)[0:1]
}

// Push adds a new language value.
func (ls *LangStack) Push(lang string) {
	*ls = append(*ls, lang)
}

// Pop removes the topmost language value.
func (ls *LangStack) Pop() {
	*ls = (*ls)[0 : len(*ls)-1]
}

// Top returns the topmost language value.
func (ls *LangStack) Top() string {
	return (*ls)[len(*ls)-1]
}

// Dup duplicates the topmost language value.
func (ls *LangStack) Dup() {
	*ls = append(*ls, (*ls)[len(*ls)-1])
}

// QuoteInfo contains language specific data about quotes.
type QuoteInfo struct {
	primLeft, primRight string
	secLeft, secRight   string
	nbsp                bool
}

// GetPrimary returns the primary left and right quote entity.
func (qi *QuoteInfo) GetPrimary() (string, string) {
	return qi.primLeft, qi.primRight
}

// GetSecondary returns the secondary left and right quote entity.
func (qi *QuoteInfo) GetSecondary() (string, string) {
	return qi.secLeft, qi.secRight
}

// GetQuotes returns quotes based on a nesting level.
func (qi *QuoteInfo) GetQuotes(level uint) (string, string) {
	if level%2 == 0 {
		return qi.GetPrimary()
	}
	return qi.GetSecondary()
}

// GetNBSp returns true, if there must be a non-breaking space between the
// quote entities and the quoted text.
func (qi *QuoteInfo) GetNBSp() bool { return qi.nbsp }

var langQuotes = map[string]*QuoteInfo{
	"":              {""", """, """, """, false},
	api.ValueLangEN: {"“", "”", "‘", "’", false},
	"de":            {"„", "“", "‚", "‘", false},
	"fr":            {"«", "»", "‹", "›", true},
}

// GetQuoteInfo returns language specific data about quotes.
func GetQuoteInfo(lang string) *QuoteInfo {
	langFields := strings.FieldsFunc(lang, func(r rune) bool { return r == '-' || r == '_' })
	for len(langFields) > 0 {
		langSup := strings.Join(langFields, "-")
		quotes, ok := langQuotes[langSup]
		if ok {
			return quotes
		}
		langFields = langFields[0 : len(langFields)-1]
	}
	return langQuotes[""]
}

//-----------------------------------------------------------------------------
// Copyright (c) 2023-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2023-present Detlef Stern
//-----------------------------------------------------------------------------

// Package shtml transforms a s-expr encoded zettel AST into a s-expr representation of HTML.
package shtml

import (
	"fmt"
	"net/url"
	"strconv"
	"strings"

	"zettelstore.de/client.fossil/api"
	"t73f.de/r/sx"
	"zettelstore.de/client.fossil/attrs"
	"zettelstore.de/client.fossil/sz"
	"zettelstore.de/client.fossil/text"
	"zettelstore.de/sx.fossil"
	"t73f.de/r/sxwebs/sxhtml"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/attrs"
	"zettelstore.de/sx.fossil/sxbuiltins/quote"
	"zettelstore.de/sx.fossil/sxeval"
	"zettelstore.de/sx.fossil/sxhtml"
	"t73f.de/r/zsc/sz"
	"t73f.de/r/zsc/text"
)

// Transformer will transform a s-expression that encodes the zettel AST into an s-expression
// Evaluator will transform a s-expression that encodes the zettel AST into an s-expression
// that represents HTML.
type Transformer struct {
type Evaluator struct {
	sf            sx.SymbolFactory
	rebinder      RebindProc
	headingOffset int64
	unique        string
	endnotes      []endnoteInfo
	noLinks       bool // true iff output must not include links
	symAttr       *sx.Symbol
	symClass      *sx.Symbol
	symMeta       *sx.Symbol
	symA          *sx.Symbol
	symSpan       *sx.Symbol
}

type endnoteInfo struct {

	fns     map[string]EvalFn
	minArgs map[string]int
	noteAST *sx.Pair // Endnote as AST
	noteHx  *sx.Pair // Endnote as SxHTML
	attrs   *sx.Pair // attrs a-list
}

// NewTransformer creates a new transformer object.
func NewTransformer(headingOffset int, sf sx.SymbolFactory) *Transformer {
	if sf == nil {
// NewEvaluator creates a new Evaluator object.
func NewEvaluator(headingOffset int) *Evaluator {
	ev := &Evaluator{
		sf = sx.MakeMappedFactory()
	}
	return &Transformer{
		sf:            sf,
		rebinder:      nil,
		headingOffset: int64(headingOffset),
		symAttr:       sf.MustMake(sxhtml.NameSymAttr),
		symClass:      sf.MustMake("class"),
		symMeta:       sf.MustMake("meta"),
		symA:          sf.MustMake("a"),
		symSpan:       sf.MustMake("span"),
	}
}


		fns:     make(map[string]EvalFn, 128),
		minArgs: make(map[string]int, 128),
	}
	ev.bindMetadata()
	ev.bindBlocks()
	ev.bindInlines()
	return ev
}
// SymbolFactory returns the symbol factory to create HTML symbols.
func (tr *Transformer) SymbolFactory() sx.SymbolFactory { return tr.sf }

// SetUnique sets a prefix to make several HTML ids unique.
func (tr *Transformer) SetUnique(s string) { tr.unique = s }
func (ev *Evaluator) SetUnique(s string) { ev.unique = s }

// IsValidName returns true, if name is a valid symbol name.
func (tr *Transformer) IsValidName(s string) bool { return tr.sf.IsValidName(s) }
func isValidName(s string) bool { return s != "" }

// Make a new HTML symbol.
func (tr *Transformer) Make(s string) *sx.Symbol { return tr.sf.MustMake(s) }

// RebindProc is a procedure which is called every time before a tranformation takes place.
type RebindProc func(*TransformEnv)

// SetRebinder sets the rebinder procedure.
func (tr *Transformer) SetRebinder(rb RebindProc) { tr.rebinder = rb }

// TransformAttrbute transforms the given attributes into a HTML s-expression.
func (tr *Transformer) TransformAttrbute(a attrs.Attributes) *sx.Pair {
// EvaluateAttrbute transforms the given attributes into a HTML s-expression.
func EvaluateAttrbute(a attrs.Attributes) *sx.Pair {
	if len(a) == 0 {
		return nil
	}
	plist := sx.Nil()
	keys := a.Keys()
	for i := len(keys) - 1; i >= 0; i-- {
		key := keys[i]
		if key != attrs.DefaultAttribute && tr.IsValidName(key) {
			plist = plist.Cons(sx.Cons(tr.Make(key), sx.MakeString(a[key])))
		if key != attrs.DefaultAttribute && isValidName(key) {
			plist = plist.Cons(sx.Cons(sx.MakeSymbol(key), sx.MakeString(a[key])))
		}
	}
	if plist == nil {
		return nil
	}
	return plist.Cons(tr.symAttr)
	return plist.Cons(sxhtml.SymAttr)
}

// TransformMeta creates a HTML meta s-expression
func (tr *Transformer) TransformMeta(a attrs.Attributes) *sx.Pair {
	return sx.Nil().Cons(tr.TransformAttrbute(a)).Cons(tr.symMeta)
}

// Transform an AST s-expression into a list of HTML s-expressions.
// Evaluate a metadata s-expression into a list of HTML s-expressions.
func (ev *Evaluator) Evaluate(lst *sx.Pair, env *Environment) (*sx.Pair, error) {
	result := ev.Eval(lst, env)
	if err := env.err; err != nil {
		return nil, err
	}
	pair, isPair := sx.GetPair(result)
	if !isPair {
		return nil, fmt.Errorf("evaluation does not result in a pair, but %T/%v", result, result)
	}

	for i := 0; i < len(env.endnotes); i++ {
		// May extend tr.endnotes -> do not use for i := range len(...)!!!

		if env.endnotes[i].noteHx != nil {
			continue
		}

func (tr *Transformer) Transform(lst *sx.Pair) (*sx.Pair, error) {
	astSF := sx.FindSymbolFactory(lst)
	if astSF != nil {
		noteHx, _ := ev.EvaluateList(env.endnotes[i].noteAST, env)
		env.endnotes[i].noteHx = noteHx
		if astSF == tr.sf {
			panic("Invalid AST SymbolFactory")
		}
	}
	} else {
		astSF = sx.MakeMappedFactory()
	}

	astEnv := sx.MakeRootEnvironment()
	engine := sxeval.MakeEngine(astSF, astEnv)
	quote.InstallQuoteSyntax(astEnv, astSF.MustMake(sz.NameSymQuote))
	te := TransformEnv{
		tr:      tr,
		astSF:   astSF,
		astEnv:  astEnv,
		err:     nil,
	return pair, nil
		textEnc: text.NewEncoder(astSF),
	}
}
	te.initialize()
	if rb := tr.rebinder; rb != nil {
		rb(&te)
	}


// EvaluateList will evaluate all list elements separately and returns them as a sx.Pair list
func (ev *Evaluator) EvaluateList(lst sx.Vector, env *Environment) (*sx.Pair, error) {
	var result sx.ListBuilder
	for _, elem := range lst {
		p := ev.Eval(elem, env)
		result.Add(p)
	}
	val, err := engine.Eval(te.astEnv, lst)
	if err != nil {
	if err := env.err; err != nil {
		return nil, err
	}
	res, isPair := sx.GetPair(val)
	if !isPair {
		panic("Result is not a list")
	}
	for i := 0; i < len(tr.endnotes); i++ {
		// May extend tr.endnotes
		val, err = engine.Eval(te.astEnv, tr.endnotes[i].noteAST)
		if err != nil {
			return res, err
	return result.List(), nil
		}
		en, ok := sx.GetPair(val)
		if !ok {
			panic("Endnote is not a list")
		}
		tr.endnotes[i].noteHx = en
	}
	return res, err

}

// Endnotes returns a SHTML object with all collected endnotes.
func (tr *Transformer) Endnotes() *sx.Pair {
	if len(tr.endnotes) == 0 {
func Endnotes(env *Environment) *sx.Pair {
	if env.err != nil || len(env.endnotes) == 0 {
		return nil
	}
	result := sx.Nil().Cons(tr.Make("ol"))
	currResult := result.AppendBang(sx.Nil().Cons(sx.Cons(tr.symClass, sx.MakeString("zs-endnotes"))).Cons(tr.symAttr))
	for i, fni := range tr.endnotes {

	var result sx.ListBuilder
	result.Add(SymOL)
	result.Add(sx.Nil().Cons(sx.Cons(SymAttrClass, sx.MakeString("zs-endnotes"))).Cons(sxhtml.SymAttr))
	for i, fni := range env.endnotes {
		noteNum := strconv.Itoa(i + 1)
		noteID := tr.unique + noteNum

		attrs := fni.attrs.Cons(sx.Cons(tr.symClass, sx.MakeString("zs-endnote"))).
			Cons(sx.Cons(tr.Make("value"), sx.MakeString(noteNum))).
			Cons(sx.Cons(tr.Make("id"), sx.MakeString("fn:"+noteID))).
			Cons(sx.Cons(tr.Make("role"), sx.MakeString("doc-endnote"))).
			Cons(tr.symAttr)
		attrs := fni.attrs.Cons(sx.Cons(SymAttrClass, sx.MakeString("zs-endnote"))).
			Cons(sx.Cons(SymAttrValue, sx.MakeString(noteNum))).
			Cons(sx.Cons(SymAttrId, sx.MakeString("fn:"+fni.noteID))).
			Cons(sx.Cons(SymAttrRole, sx.MakeString("doc-endnote"))).
			Cons(sxhtml.SymAttr)

		backref := sx.Nil().Cons(sx.MakeString("\u21a9\ufe0e")).
			Cons(sx.Nil().
				Cons(sx.Cons(tr.symClass, sx.MakeString("zs-endnote-backref"))).
				Cons(sx.Cons(tr.Make("href"), sx.MakeString("#fnref:"+noteID))).
				Cons(sx.Cons(tr.Make("role"), sx.MakeString("doc-backlink"))).
				Cons(tr.symAttr)).
			Cons(tr.symA)
				Cons(sx.Cons(SymAttrClass, sx.MakeString("zs-endnote-backref"))).
				Cons(sx.Cons(SymAttrHref, sx.MakeString("#fnref:"+fni.noteID))).
				Cons(sx.Cons(SymAttrRole, sx.MakeString("doc-backlink"))).
				Cons(sxhtml.SymAttr)).
			Cons(SymA)

		li := sx.Nil().Cons(tr.Make("li"))
		li.AppendBang(attrs).
			ExtendBang(fni.noteHx).
			AppendBang(sx.MakeString(" ")).AppendBang(backref)
		currResult = currResult.AppendBang(li)
		var li sx.ListBuilder
		li.Add(SymLI)
		li.Add(attrs)
		li.ExtendBang(fni.noteHx)
		li.Add(sx.MakeString(" "))
		li.Add(backref)
		result.Add(li.List())
	}
	tr.endnotes = nil
	return result
	return result.List()
}

// Environment where sz objects are evaluated to shtml objects
type Environment struct {
	err          error
	langStack    LangStack
	endnotes     []endnoteInfo
	quoteNesting uint
}
type endnoteInfo struct {
	noteID  string    // link id
	noteAST sx.Vector // Endnote as list of AST inline elements
	attrs   *sx.Pair  // attrs a-list
	noteHx  *sx.Pair  // Endnote as SxHTML
}

// TransformEnv is the environment where the actual transformation takes places.
type TransformEnv struct {
// MakeEnvironment builds a new evaluation environment.
func MakeEnvironment(lang string) Environment {
	tr          *Transformer
	astSF       sx.SymbolFactory
	astEnv      sx.Environment
	err         error
	return Environment{
		err:          nil,
	textEnc     *text.Encoder
	symNoEscape *sx.Symbol
	symAttr     *sx.Symbol
	symA        *sx.Symbol
		langStack:    NewLangStack(lang),
		endnotes:     nil,
	symSpan     *sx.Symbol
	symP        *sx.Symbol
}

func (te *TransformEnv) initialize() {
	te.symNoEscape = te.Make(sxhtml.NameSymNoEscape)
	te.symAttr = te.tr.symAttr
	te.symA = te.tr.symA
	te.symSpan = te.tr.symSpan
	te.symP = te.Make("p")
		quoteNesting: 0,
	}
}

// GetError returns the last error found.
func (env *Environment) GetError() error { return env.err }

// Reset the environment.
func (env *Environment) Reset() {
	env.langStack.Reset()
	env.endnotes = nil
	env.quoteNesting = 0
}

// pushAttribute adds the current attributes to the environment.
func (env *Environment) pushAttributes(a attrs.Attributes) {
	if value, ok := a.Get("lang"); ok {
		env.langStack.Push(value)
	} else {
		env.langStack.Dup()
	}
}

// popAttributes removes the current attributes from the envrionment.
func (env *Environment) popAttributes() { env.langStack.Pop() }

// getLanguage returns the current language.
func (env *Environment) getLanguage() string { return env.langStack.Top() }
	te.bind(sz.NameSymList, 0, listArgs)
	te.bindMetadata()
	te.bindBlocks()
	te.bindInlines()
}

func listArgs(args []sx.Object) sx.Object { return sx.MakeList(args...) }

func (te *TransformEnv) bindMetadata() {
	te.bind(sz.NameSymMeta, 0, listArgs)

func (env *Environment) getQuotes() (string, string, bool) {
	qi := GetQuoteInfo(env.getLanguage())
	leftQ, rightQ := qi.GetQuotes(env.quoteNesting)
	return leftQ, rightQ, qi.GetNBSp()
}

// EvalFn is a function to be called for evaluation.
type EvalFn func(sx.Vector, *Environment) sx.Object

func (ev *Evaluator) bind(sym *sx.Symbol, minArgs int, fn EvalFn) {
	symVal := sym.GetValue()
	ev.fns[symVal] = fn
	if minArgs > 0 {
		ev.minArgs[symVal] = minArgs
	}
}

// ResolveBinding returns the function bound to the given name.
func (ev *Evaluator) ResolveBinding(sym *sx.Symbol) EvalFn {
	if fn, found := ev.fns[sym.GetValue()]; found {
		return fn
	}
	return nil
}

// Rebind overwrites a binding, but leaves the minimum number of arguments intact.
func (ev *Evaluator) Rebind(sym *sx.Symbol, fn EvalFn) {
	symVal := sym.GetValue()
	if _, found := ev.fns[symVal]; !found {
		panic(sym)
	}
	ev.fns[symVal] = fn
}

func (ev *Evaluator) bindMetadata() {
	ev.bind(sz.SymMeta, 0, ev.evalList)
	te.bind(sz.NameSymTypeZettelmarkup, 2, func(args []sx.Object) sx.Object {
		a := make(attrs.Attributes, 2).
			Set("name", te.getSymbol(args[0]).String()).
			Set("content", te.textEnc.Encode(te.getList(args[1])))
		return te.transformMeta(a)
	})
	metaString := func(args []sx.Object) sx.Object {
	evalMetaString := func(args sx.Vector, env *Environment) sx.Object {
		a := make(attrs.Attributes, 2).
			Set("name", te.getSymbol(args[0]).Name()).
			Set("content", te.getString(args[1]).String())
		return te.transformMeta(a)
			Set("name", getSymbol(args[0], env).GetValue()).
			Set("content", getString(args[1], env).GetValue())
		return ev.EvaluateMeta(a)
	}
	te.bind(sz.NameSymTypeCredential, 2, metaString)
	te.bind(sz.NameSymTypeEmpty, 2, metaString)
	te.bind(sz.NameSymTypeID, 2, metaString)
	te.bind(sz.NameSymTypeNumber, 2, metaString)
	te.bind(sz.NameSymTypeString, 2, metaString)
	te.bind(sz.NameSymTypeTimestamp, 2, metaString)
	te.bind(sz.NameSymTypeURL, 2, metaString)
	te.bind(sz.NameSymTypeWord, 2, metaString)
	metaSet := func(args []sx.Object) sx.Object {
	ev.bind(sz.SymTypeCredential, 2, evalMetaString)
	ev.bind(sz.SymTypeEmpty, 2, evalMetaString)
	ev.bind(sz.SymTypeID, 2, evalMetaString)
	ev.bind(sz.SymTypeNumber, 2, evalMetaString)
	ev.bind(sz.SymTypeString, 2, evalMetaString)
	ev.bind(sz.SymTypeTimestamp, 2, evalMetaString)
	ev.bind(sz.SymTypeURL, 2, evalMetaString)
	ev.bind(sz.SymTypeWord, 2, evalMetaString)

	evalMetaSet := func(args sx.Vector, env *Environment) sx.Object {
		var sb strings.Builder
		for elem := te.getList(args[1]); elem != nil; elem = elem.Tail() {
		for elem := getList(args[1], env); elem != nil; elem = elem.Tail() {
			sb.WriteByte(' ')
			sb.WriteString(te.getString(elem.Car()).String())
			sb.WriteString(getString(elem.Car(), env).GetValue())
		}
		s := sb.String()
		if len(s) > 0 {
			s = s[1:]
		}
		a := make(attrs.Attributes, 2).
			Set("name", te.getSymbol(args[0]).Name()).
			Set("name", getSymbol(args[0], env).GetValue()).
			Set("content", s)
		return te.transformMeta(a)
		return ev.EvaluateMeta(a)
	}
	te.bind(sz.NameSymTypeIDSet, 2, metaSet)
	te.bind(sz.NameSymTypeTagSet, 2, metaSet)
	te.bind(sz.NameSymTypeWordSet, 2, metaSet)
	ev.bind(sz.SymTypeIDSet, 2, evalMetaSet)
	ev.bind(sz.SymTypeTagSet, 2, evalMetaSet)
	ev.bind(sz.SymTypeZettelmarkup, 2, func(args sx.Vector, env *Environment) sx.Object {
		a := make(attrs.Attributes, 2).
			Set("name", getSymbol(args[0], env).GetValue()).
			Set("content", text.EvaluateInlineString(getList(args[1], env)))
		return ev.EvaluateMeta(a)
	})
}

// EvaluateMeta returns HTML meta object for an attribute.
func (ev *Evaluator) EvaluateMeta(a attrs.Attributes) *sx.Pair {
	return sx.Nil().Cons(EvaluateAttrbute(a)).Cons(SymMeta)
}

func (te *TransformEnv) bindBlocks() {
	te.bind(sz.NameSymBlock, 0, listArgs)
	te.bind(sz.NameSymPara, 0, func(args []sx.Object) sx.Object {
func (ev *Evaluator) bindBlocks() {
	ev.bind(sz.SymBlock, 0, ev.evalList)
	ev.bind(sz.SymPara, 0, func(args sx.Vector, env *Environment) sx.Object {
		// for ; args != nil; args = args.Tail() {
		// 	lst, ok := sx.GetList(args.Car())
		// 	if !ok || lst != nil {
		// 		break
		// 	}
		// }
		return sx.MakeList(args...).Cons(te.symP)
		return ev.evalSlice(args, env).Cons(SymP)
	})
	te.bind(sz.NameSymHeading, 5, func(args []sx.Object) sx.Object {
		nLevel := te.getInt64(args[0])
	ev.bind(sz.SymHeading, 5, func(args sx.Vector, env *Environment) sx.Object {
		nLevel := getInt64(args[0], env)
		if nLevel <= 0 {
			te.err = fmt.Errorf("%v is a negative level", nLevel)
			env.err = fmt.Errorf("%v is a negative heading level", nLevel)
			return sx.Nil()
		}
		level := strconv.FormatInt(nLevel+te.tr.headingOffset, 10)
		level := strconv.FormatInt(nLevel+ev.headingOffset, 10)
		headingSymbol := sx.MakeSymbol("h" + level)

		a := te.getAttributes(args[1])
		if fragment := te.getString(args[3]).String(); fragment != "" {
			a = a.Set("id", te.tr.unique+fragment)
		a := GetAttributes(args[1], env)
		env.pushAttributes(a)
		defer env.popAttributes()
		if fragment := getString(args[3], env).GetValue(); fragment != "" {
			a = a.Set("id", ev.unique+fragment)
		}

		if result, isPair := sx.GetPair(args[4]); isPair && result != nil {
		if result, _ := ev.EvaluateList(args[4:], env); result != nil {
			if len(a) > 0 {
				result = result.Cons(te.transformAttribute(a))
				result = result.Cons(EvaluateAttrbute(a))
			}
			return result.Cons(te.Make("h" + level))
			return result.Cons(headingSymbol)
		}
		return sx.MakeList(te.Make("h"+level), sx.MakeString("<MISSING TEXT>"))
		return sx.MakeList(headingSymbol, sx.MakeString("<MISSING TEXT>"))
	})
	te.bind(sz.NameSymThematic, 0, func(args []sx.Object) sx.Object {
	ev.bind(sz.SymThematic, 0, func(args sx.Vector, env *Environment) sx.Object {
		result := sx.Nil()
		if len(args) > 0 {
			if attrList := te.getList(args[0]); attrList != nil {
				result = result.Cons(te.transformAttribute(sz.GetAttributes(attrList)))
			if attrList := getList(args[0], env); attrList != nil {
				result = result.Cons(EvaluateAttrbute(sz.GetAttributes(attrList)))
			}
		}
		return result.Cons(te.Make("hr"))
		return result.Cons(SymHR)
	})

	te.bind(sz.NameSymListOrdered, 0, te.makeListFn("ol"))
	te.bind(sz.NameSymListUnordered, 0, te.makeListFn("ul"))
	te.bind(sz.NameSymDescription, 0, func(args []sx.Object) sx.Object {
	ev.bind(sz.SymListOrdered, 0, ev.makeListFn(SymOL))
	ev.bind(sz.SymListUnordered, 0, ev.makeListFn(SymUL))
	ev.bind(sz.SymDescription, 0, func(args sx.Vector, env *Environment) sx.Object {
		if len(args) == 0 {
			return sx.Nil()
		}
		items := sx.Nil().Cons(te.Make("dl"))
		curItem := items
		var items sx.ListBuilder
		items.Add(symDL)
		for pos := 0; pos < len(args); pos++ {
			term := te.getList(args[pos])
			curItem = curItem.AppendBang(term.Cons(te.Make("dt")))
			term := ev.evalDescriptionTerm(getList(args[pos], env), env)
			items.Add(term.Cons(symDT))
			pos++
			if pos >= len(args) {
				break
			}
			ddBlock := te.getList(args[pos])
			ddBlock := getList(ev.Eval(args[pos], env), env)
			if ddBlock == nil {
				break
				continue
			}
			for ddlst := ddBlock; ddlst != nil; ddlst = ddlst.Tail() {
				dditem := te.getList(ddlst.Car())
				curItem = curItem.AppendBang(dditem.Cons(te.Make("dd")))
				dditem := getList(ddlst.Car(), env)
				items.Add(dditem.Cons(symDD))
			}
		}
		return items
		return items.List()
	})

	te.bind(sz.NameSymListQuote, 0, func(args []sx.Object) sx.Object {
	ev.bind(sz.SymListQuote, 0, func(args sx.Vector, env *Environment) sx.Object {
		if args == nil {
			return sx.Nil()
		}
		result := sx.Nil().Cons(te.Make("blockquote"))
		currResult := result
		var result sx.ListBuilder
		result.Add(symBLOCKQUOTE)
		for _, elem := range args {
			if quote, isPair := sx.GetPair(elem); isPair {
				currResult = currResult.AppendBang(quote.Cons(te.symP))
			if quote, isPair := sx.GetPair(ev.Eval(elem, env)); isPair {
				result.Add(quote.Cons(sxhtml.SymListSplice))
			}
		}
		return result
		return result.List()
	})

	te.bind(sz.NameSymTable, 1, func(args []sx.Object) sx.Object {
	ev.bind(sz.SymTable, 1, func(args sx.Vector, env *Environment) sx.Object {
		thead := sx.Nil()
		if header := te.getList(args[0]); !sx.IsNil(header) {
			thead = sx.Nil().Cons(te.transformTableRow(header)).Cons(te.Make("thead"))
		if header := getList(args[0], env); !sx.IsNil(header) {
			thead = sx.Nil().Cons(ev.evalTableRow(symTH, header, env)).Cons(symTHEAD)
		}

		tbody := sx.Nil()
		var tbody sx.ListBuilder
		if len(args) > 1 {
			tbody = sx.Nil().Cons(te.Make("tbody"))
			curBody := tbody
			tbody.Add(symTBODY)
			for _, row := range args[1:] {
				curBody = curBody.AppendBang(te.transformTableRow(te.getList(row)))
				tbody.Add(ev.evalTableRow(symTD, getList(row, env), env))
			}
		}

		table := sx.Nil()
		if tbody != nil {
			table = table.Cons(tbody)
		if !tbody.IsEmpty() {
			table = table.Cons(tbody.List())
		}
		if thead != nil {
			table = table.Cons(thead)
		}
		if table == nil {
			return sx.Nil()
		}
		return table.Cons(te.Make("table"))
		return table.Cons(symTABLE)
	})
	te.bind(sz.NameSymCell, 0, te.makeCellFn(""))
	te.bind(sz.NameSymCellCenter, 0, te.makeCellFn("center"))
	te.bind(sz.NameSymCellLeft, 0, te.makeCellFn("left"))
	te.bind(sz.NameSymCellRight, 0, te.makeCellFn("right"))
	ev.bind(sz.SymCell, 0, ev.makeCellFn(""))
	ev.bind(sz.SymCellCenter, 0, ev.makeCellFn("center"))
	ev.bind(sz.SymCellLeft, 0, ev.makeCellFn("left"))
	ev.bind(sz.SymCellRight, 0, ev.makeCellFn("right"))

	te.bind(sz.NameSymRegionBlock, 2, te.makeRegionFn(te.Make("div"), true))
	te.bind(sz.NameSymRegionQuote, 2, te.makeRegionFn(te.Make("blockquote"), false))
	te.bind(sz.NameSymRegionVerse, 2, te.makeRegionFn(te.Make("div"), false))
	ev.bind(sz.SymRegionBlock, 2, ev.makeRegionFn(SymDIV, true))
	ev.bind(sz.SymRegionQuote, 2, ev.makeRegionFn(symBLOCKQUOTE, false))
	ev.bind(sz.SymRegionVerse, 2, ev.makeRegionFn(SymDIV, false))

	te.bind(sz.NameSymVerbatimComment, 1, func(args []sx.Object) sx.Object {
		if te.getAttributes(args[0]).HasDefault() {
	ev.bind(sz.SymVerbatimComment, 1, func(args sx.Vector, env *Environment) sx.Object {
		if GetAttributes(args[0], env).HasDefault() {
			if len(args) > 1 {
				if s := te.getString(args[1]); s != "" {
				if s := getString(args[1], env); s.GetValue() != "" {
					t := sx.MakeString(s.String())
					return sx.Nil().Cons(t).Cons(te.Make(sxhtml.NameSymBlockComment))
					return sx.Nil().Cons(s).Cons(sxhtml.SymBlockComment)
				}
			}
		}
		return nil
	})

	te.bind(sz.NameSymVerbatimEval, 2, func(args []sx.Object) sx.Object {
		return te.transformVerbatim(te.getAttributes(args[0]).AddClass("zs-eval"), te.getString(args[1]))
	ev.bind(sz.SymVerbatimEval, 2, func(args sx.Vector, env *Environment) sx.Object {
		return evalVerbatim(GetAttributes(args[0], env).AddClass("zs-eval"), getString(args[1], env))
	})
	te.bind(sz.NameSymVerbatimHTML, 2, te.transformHTML)
	te.bind(sz.NameSymVerbatimMath, 2, func(args []sx.Object) sx.Object {
		return te.transformVerbatim(te.getAttributes(args[0]).AddClass("zs-math"), te.getString(args[1]))
	ev.bind(sz.SymVerbatimHTML, 2, ev.evalHTML)
	ev.bind(sz.SymVerbatimMath, 2, func(args sx.Vector, env *Environment) sx.Object {
		return evalVerbatim(GetAttributes(args[0], env).AddClass("zs-math"), getString(args[1], env))
	})
	te.bind(sz.NameSymVerbatimProg, 2, func(args []sx.Object) sx.Object {
		a := te.getAttributes(args[0])
		content := te.getString(args[1])
	ev.bind(sz.SymVerbatimProg, 2, func(args sx.Vector, env *Environment) sx.Object {
		a := GetAttributes(args[0], env)
		content := getString(args[1], env)
		if a.HasDefault() {
			content = sx.MakeString(visibleReplacer.Replace(content.String()))
			content = sx.MakeString(visibleReplacer.Replace(content.GetValue()))
		}
		return te.transformVerbatim(a, content)
		return evalVerbatim(a, content)
	})
	te.bind(sz.NameSymVerbatimZettel, 0, func([]sx.Object) sx.Object { return sx.Nil() })

	ev.bind(sz.SymVerbatimZettel, 0, nilFn)
	ev.bind(sz.SymBLOB, 3, func(args sx.Vector, env *Environment) sx.Object {
	te.bind(sz.NameSymBLOB, 3, func(args []sx.Object) sx.Object {
		return te.transformBLOB(te.getList(args[0]), te.getString(args[1]), te.getString(args[2]))
		return evalBLOB(getList(args[0], env), getString(args[1], env), getString(args[2], env))
	})

	te.bind(sz.NameSymTransclude, 2, func(args []sx.Object) sx.Object {
	ev.bind(sz.SymTransclude, 2, func(args sx.Vector, env *Environment) sx.Object {
		ref, isPair := sx.GetPair(args[1])
		if !isPair {
			return sx.Nil()
		}
		refKind := ref.Car()
		if sx.IsNil(refKind) {
			return sx.Nil()
		}
		if refValue := te.getString(ref.Tail().Car()); refValue != "" {
			if te.astSF.MustMake(sz.NameSymRefStateExternal).IsEqual(refKind) {
				a := te.getAttributes(args[0]).Set("src", refValue.String()).AddClass("external")
				return sx.Nil().Cons(sx.Nil().Cons(te.transformAttribute(a)).Cons(te.Make("img"))).Cons(te.symP)
		if refValue := getString(ref.Tail().Car(), env); refValue.GetValue() != "" {
			if refSym, isRefSym := sx.GetSymbol(refKind); isRefSym && refSym.IsEqualSymbol(sz.SymRefStateExternal) {
				a := GetAttributes(args[0], env).Set("src", refValue.GetValue()).AddClass("external")
				return sx.Nil().Cons(sx.Nil().Cons(EvaluateAttrbute(a)).Cons(SymIMG)).Cons(SymP)
			}
			return sx.MakeList(
				te.Make(sxhtml.NameSymInlineComment),
				sxhtml.SymInlineComment,
				sx.MakeString("transclude"),
				refKind,
				sx.MakeString("->"),
				refValue,
			)
		}
		return sx.MakeList(args...)
		return ev.evalSlice(args, env)
	})
}

func (te *TransformEnv) makeListFn(tag string) transformFn {
func (ev *Evaluator) makeListFn(sym *sx.Symbol) EvalFn {
	sym := te.Make(tag)
	return func(args []sx.Object) sx.Object {
		result := sx.Nil().Cons(sym)
		last := result
	return func(args sx.Vector, env *Environment) sx.Object {
		var result sx.ListBuilder
		result.Add(sym)
		for _, elem := range args {
			item := sx.Nil().Cons(te.Make("li"))
			if res, isPair := sx.GetPair(elem); isPair {
			item := sx.Nil().Cons(SymLI)
			if res, isPair := sx.GetPair(ev.Eval(elem, env)); isPair {
				item.ExtendBang(res)
			}
			last = last.AppendBang(item)
			result.Add(item)
		}
		return result
		return result.List()
	}
}
func (te *TransformEnv) transformTableRow(pairs *sx.Pair) *sx.Pair {
	row := sx.Nil().Cons(te.Make("tr"))

func (ev *Evaluator) evalDescriptionTerm(term *sx.Pair, env *Environment) *sx.Pair {
	var result sx.ListBuilder
	for node := term; node != nil; node = node.Tail() {
		elem := ev.Eval(node.Car(), env)
		result.Add(elem)
	}
	return result.List()
}

func (ev *Evaluator) evalTableRow(sym *sx.Symbol, pairs *sx.Pair, env *Environment) *sx.Pair {
	if pairs == nil {
		return nil
	}
	curRow := row
	var row sx.ListBuilder
	row.Add(symTR)
	for pair := pairs; pair != nil; pair = pair.Tail() {
		curRow = curRow.AppendBang(pair.Car())
		row.Add(sx.Cons(sym, ev.Eval(pair.Car(), env)))
	}
	return row
	return row.List()
}

func (te *TransformEnv) makeCellFn(align string) transformFn {
	return func(args []sx.Object) sx.Object {
		tdata := sx.MakeList(args...)
func (ev *Evaluator) makeCellFn(align string) EvalFn {
	return func(args sx.Vector, env *Environment) sx.Object {
		tdata := ev.evalSlice(args, env)
		if align != "" {
			tdata = tdata.Cons(te.transformAttribute(attrs.Attributes{"class": align}))
			tdata = tdata.Cons(EvaluateAttrbute(attrs.Attributes{"class": align}))
		}
		return tdata.Cons(te.Make("td"))
		return tdata
	}
}

func (te *TransformEnv) makeRegionFn(sym *sx.Symbol, genericToClass bool) transformFn {
	return func(args []sx.Object) sx.Object {
		a := te.getAttributes(args[0])
func (ev *Evaluator) makeRegionFn(sym *sx.Symbol, genericToClass bool) EvalFn {
	return func(args sx.Vector, env *Environment) sx.Object {
		a := GetAttributes(args[0], env)
		env.pushAttributes(a)
		defer env.popAttributes()
		if genericToClass {
			if val, found := a.Get(""); found {
				a = a.Remove("").AddClass(val)
			}
		}
		var result sx.ListBuilder
		result := sx.Nil()
		result.Add(sym)
		if len(a) > 0 {
			result = result.Cons(te.transformAttribute(a))
			result.Add(EvaluateAttrbute(a))
		}
		result = result.Cons(sym)
		currResult := result.LastPair()
		if region, isPair := sx.GetPair(args[1]); isPair {
			if evalRegion := ev.EvalPairList(region, env); evalRegion != nil {
			currResult = currResult.ExtendBang(region)
		}
				result.ExtendBang(evalRegion)
			}
		}
		if len(args) > 2 {
			if cite, isPair := sx.GetPair(args[2]); isPair && cite != nil {
				currResult.AppendBang(cite.Cons(te.Make("cite")))
			if cite, _ := ev.EvaluateList(args[2:], env); cite != nil {
				result.Add(cite.Cons(symCITE))
			}
		}
		return result
		return result.List()
	}
}

func (te *TransformEnv) transformVerbatim(a attrs.Attributes, s sx.String) sx.Object {
func evalVerbatim(a attrs.Attributes, s sx.String) sx.Object {
	a = setProgLang(a)
	code := sx.Nil().Cons(s)
	if al := te.transformAttribute(a); al != nil {
	if al := EvaluateAttrbute(a); al != nil {
		code = code.Cons(al)
	}
	code = code.Cons(te.Make("code"))
	return sx.Nil().Cons(code).Cons(te.Make("pre"))
	code = code.Cons(symCODE)
	return sx.Nil().Cons(code).Cons(symPRE)
}

func (te *TransformEnv) bindInlines() {
	te.bind(sz.NameSymInline, 0, listArgs)
	te.bind(sz.NameSymText, 1, func(args []sx.Object) sx.Object { return te.getString(args[0]) })
func (ev *Evaluator) bindInlines() {
	ev.bind(sz.SymInline, 0, ev.evalList)
	ev.bind(sz.SymText, 1, func(args sx.Vector, env *Environment) sx.Object { return getString(args[0], env) })
	te.bind(sz.NameSymSpace, 0, func(args []sx.Object) sx.Object {
		if len(args) == 0 {
			return sx.MakeString(" ")
		}
		return te.getString(args[0])
	})
	te.bind(sz.NameSymSoft, 0, func([]sx.Object) sx.Object { return sx.MakeString(" ") })
	ev.bind(sz.SymSoft, 0, func(sx.Vector, *Environment) sx.Object { return sx.MakeString(" ") })
	brSym := te.Make("br")
	te.bind(sz.NameSymHard, 0, func([]sx.Object) sx.Object { return sx.Nil().Cons(brSym) })
	ev.bind(sz.SymHard, 0, func(sx.Vector, *Environment) sx.Object { return sx.Nil().Cons(symBR) })

	te.bind(sz.NameSymLinkInvalid, 2, func(args []sx.Object) sx.Object {
		// a := te.getAttributes(args)
	ev.bind(sz.SymLinkInvalid, 2, func(args sx.Vector, env *Environment) sx.Object {
		a := GetAttributes(args[0], env)
		env.pushAttributes(a)
		defer env.popAttributes()
		var inline *sx.Pair
		if len(args) > 2 {
			inline = sx.MakeList(args[2:]...)
			inline = ev.evalSlice(args[2:], env)
		}
		if inline == nil {
			inline = sx.Nil().Cons(args[1])
			inline = sx.Nil().Cons(ev.Eval(args[1], env))
		}
		return inline.Cons(te.symSpan)
		return inline.Cons(SymSPAN)
	})
	transformHREF := func(args []sx.Object) sx.Object {
		a := te.getAttributes(args[0])
		refValue := te.getString(args[1])
		return te.transformLink(a.Set("href", refValue.String()), refValue, args[2:])
	evalHREF := func(args sx.Vector, env *Environment) sx.Object {
		a := GetAttributes(args[0], env)
		env.pushAttributes(a)
		defer env.popAttributes()
		refValue := getString(args[1], env)
		return ev.evalLink(a.Set("href", refValue.GetValue()), refValue, args[2:], env)
	}
	te.bind(sz.NameSymLinkZettel, 2, transformHREF)
	te.bind(sz.NameSymLinkSelf, 2, transformHREF)
	te.bind(sz.NameSymLinkFound, 2, transformHREF)
	te.bind(sz.NameSymLinkBroken, 2, func(args []sx.Object) sx.Object {
		a := te.getAttributes(args[0])
		refValue := te.getString(args[1])
		return te.transformLink(a.AddClass("broken"), refValue, args[2:])
	ev.bind(sz.SymLinkZettel, 2, evalHREF)
	ev.bind(sz.SymLinkSelf, 2, evalHREF)
	ev.bind(sz.SymLinkFound, 2, evalHREF)
	ev.bind(sz.SymLinkBroken, 2, func(args sx.Vector, env *Environment) sx.Object {
		a := GetAttributes(args[0], env)
		env.pushAttributes(a)
		defer env.popAttributes()
		refValue := getString(args[1], env)
		return ev.evalLink(a.AddClass("broken"), refValue, args[2:], env)
	})
	te.bind(sz.NameSymLinkHosted, 2, transformHREF)
	te.bind(sz.NameSymLinkBased, 2, transformHREF)
	te.bind(sz.NameSymLinkQuery, 2, func(args []sx.Object) sx.Object {
		a := te.getAttributes(args[0])
		refValue := te.getString(args[1])
		query := "?" + api.QueryKeyQuery + "=" + url.QueryEscape(refValue.String())
		return te.transformLink(a.Set("href", query), refValue, args[2:])
	ev.bind(sz.SymLinkHosted, 2, evalHREF)
	ev.bind(sz.SymLinkBased, 2, evalHREF)
	ev.bind(sz.SymLinkQuery, 2, func(args sx.Vector, env *Environment) sx.Object {
		a := GetAttributes(args[0], env)
		env.pushAttributes(a)
		defer env.popAttributes()
		refValue := getString(args[1], env)
		query := "?" + api.QueryKeyQuery + "=" + url.QueryEscape(refValue.GetValue())
		return ev.evalLink(a.Set("href", query), refValue, args[2:], env)
	})
	te.bind(sz.NameSymLinkExternal, 2, func(args []sx.Object) sx.Object {
		a := te.getAttributes(args[0])
		refValue := te.getString(args[1])
		return te.transformLink(a.Set("href", refValue.String()).AddClass("external"), refValue, args[2:])
	})

	te.bind(sz.NameSymEmbed, 3, func(args []sx.Object) sx.Object {
		ref := te.getList(args[1])
	ev.bind(sz.SymLinkExternal, 2, func(args sx.Vector, env *Environment) sx.Object {
		a := GetAttributes(args[0], env)
		syntax := te.getString(args[2])
		if syntax == api.ValueSyntaxSVG {
			embedAttr := sx.MakeList(
				te.symAttr,
		env.pushAttributes(a)
		defer env.popAttributes()
				sx.Cons(te.Make("type"), sx.MakeString("image/svg+xml")),
				sx.Cons(te.Make("src"), sx.MakeString("/"+te.getString(ref.Tail()).String()+".svg")),
			)
		refValue := getString(args[1], env)
		return ev.evalLink(a.Set("href", refValue.GetValue()).Add("rel", "external"), refValue, args[2:], env)
	})

			return sx.MakeList(
				te.Make("figure"),
				sx.MakeList(
	ev.bind(sz.SymEmbed, 3, func(args sx.Vector, env *Environment) sx.Object {
		ref := getList(args[1], env)
					te.Make("embed"),
					embedAttr,
				),
			)
		}
		a := te.getAttributes(args[0])
		a = a.Set("src", string(te.getString(ref.Tail().Car())))
		var sb strings.Builder
		te.flattenText(&sb, ref.Tail().Tail().Tail())
		if d := sb.String(); d != "" {
			a = a.Set("alt", d)
		}
		return sx.MakeList(te.Make("img"), te.transformAttribute(a))
		a := GetAttributes(args[0], env)
		a = a.Set("src", getString(ref.Tail().Car(), env).GetValue())
		if len(args) > 3 {
			var sb strings.Builder
			flattenText(&sb, sx.MakeList(args[3:]...))
			if d := sb.String(); d != "" {
				a = a.Set("alt", d)
			}
		}
		return sx.MakeList(SymIMG, EvaluateAttrbute(a))
	})
	te.bind(sz.NameSymEmbedBLOB, 3, func(args []sx.Object) sx.Object {
		a, syntax, data := te.getAttributes(args[0]), te.getString(args[1]), te.getString(args[2])
		summary, _ := a.Get(api.KeySummary)
		return te.transformBLOB(
			sx.MakeList(te.astSF.MustMake(sz.NameSymInline), sx.MakeString(summary)),
	ev.bind(sz.SymEmbedBLOB, 3, func(args sx.Vector, env *Environment) sx.Object {
		a, syntax, data := GetAttributes(args[0], env), getString(args[1], env), getString(args[2], env)
		summary, hasSummary := a.Get(api.KeySummary)
		if !hasSummary {
			summary = ""
		}
		return evalBLOB(
			sx.MakeList(sxhtml.SymListSplice, sx.MakeString(summary)),
			syntax,
			data,
		)
	})

	te.bind(sz.NameSymCite, 2, func(args []sx.Object) sx.Object {
	ev.bind(sz.SymCite, 2, func(args sx.Vector, env *Environment) sx.Object {
		a := GetAttributes(args[0], env)
		env.pushAttributes(a)
		defer env.popAttributes()
		result := sx.Nil()
		if key := te.getString(args[1]); key != "" {
		if key := getString(args[1], env); key.GetValue() != "" {
			if len(args) > 2 {
				result = sx.MakeList(args[2:]...).Cons(sx.MakeString(", "))
				result = ev.evalSlice(args[2:], env).Cons(sx.MakeString(", "))
			}
			result = result.Cons(key)
		}
		if a := te.getAttributes(args[0]); len(a) > 0 {
			result = result.Cons(te.transformAttribute(a))
		if len(a) > 0 {
			result = result.Cons(EvaluateAttrbute(a))
		}
		if result == nil {
			return nil
		}
		return result.Cons(te.symSpan)
		return result.Cons(SymSPAN)
	})

	ev.bind(sz.SymMark, 3, func(args sx.Vector, env *Environment) sx.Object {
	te.bind(sz.NameSymMark, 3, func(args []sx.Object) sx.Object {
		result := sx.MakeList(args[3:]...)
		if !te.tr.noLinks {
			if fragment := te.getString(args[2]); fragment != "" {
				a := attrs.Attributes{"id": fragment.String() + te.tr.unique}
				return result.Cons(te.transformAttribute(a)).Cons(te.symA)
		result := ev.evalSlice(args[3:], env)
		if !ev.noLinks {
			if fragment := getString(args[2], env).GetValue(); fragment != "" {
				a := attrs.Attributes{"id": fragment + ev.unique}
				return result.Cons(EvaluateAttrbute(a)).Cons(SymA)
			}
		}
		return result.Cons(te.symSpan)
		return result.Cons(SymSPAN)
	})

	te.bind(sz.NameSymEndnote, 1, func(args []sx.Object) sx.Object {
	ev.bind(sz.SymEndnote, 1, func(args sx.Vector, env *Environment) sx.Object {
		a := GetAttributes(args[0], env)
		env.pushAttributes(a)
		defer env.popAttributes()
		attrPlist := sx.Nil()
		if a := te.getAttributes(args[0]); len(a) > 0 {
			if attrs := te.transformAttribute(a); attrs != nil {
		if len(a) > 0 {
			if attrs := EvaluateAttrbute(a); attrs != nil {
				attrPlist = attrs.Tail()
			}
		}

		text, isPair := sx.GetPair(args[1])
		if !isPair {
			return sx.Nil()
		}
		te.tr.endnotes = append(te.tr.endnotes, endnoteInfo{noteAST: text, noteHx: nil, attrs: attrPlist})
		noteNum := strconv.Itoa(len(te.tr.endnotes))
		noteID := te.tr.unique + noteNum
		hrefAttr := sx.Nil().Cons(sx.Cons(te.Make("role"), sx.MakeString("doc-noteref"))).
			Cons(sx.Cons(te.Make("href"), sx.MakeString("#fn:"+noteID))).
			Cons(sx.Cons(te.tr.symClass, sx.MakeString("zs-noteref"))).
			Cons(te.symAttr)
		href := sx.Nil().Cons(sx.MakeString(noteNum)).Cons(hrefAttr).Cons(te.symA)
		supAttr := sx.Nil().Cons(sx.Cons(te.Make("id"), sx.MakeString("fnref:"+noteID))).Cons(te.symAttr)
		return sx.Nil().Cons(href).Cons(supAttr).Cons(te.Make("sup"))
		noteNum := strconv.Itoa(len(env.endnotes) + 1)
		noteID := ev.unique + noteNum
		env.endnotes = append(env.endnotes, endnoteInfo{
			noteID: noteID, noteAST: args[1:], noteHx: nil, attrs: attrPlist})
		hrefAttr := sx.Nil().Cons(sx.Cons(SymAttrRole, sx.MakeString("doc-noteref"))).
			Cons(sx.Cons(SymAttrHref, sx.MakeString("#fn:"+noteID))).
			Cons(sx.Cons(SymAttrClass, sx.MakeString("zs-noteref"))).
			Cons(sxhtml.SymAttr)
		href := sx.Nil().Cons(sx.MakeString(noteNum)).Cons(hrefAttr).Cons(SymA)
		supAttr := sx.Nil().Cons(sx.Cons(SymAttrId, sx.MakeString("fnref:"+noteID))).Cons(sxhtml.SymAttr)
		return sx.Nil().Cons(href).Cons(supAttr).Cons(symSUP)
	})

	te.bind(sz.NameSymFormatDelete, 1, te.makeFormatFn("del"))
	te.bind(sz.NameSymFormatEmph, 1, te.makeFormatFn("em"))
	te.bind(sz.NameSymFormatInsert, 1, te.makeFormatFn("ins"))
	te.bind(sz.NameSymFormatQuote, 1, te.transformQuote)
	te.bind(sz.NameSymFormatSpan, 1, te.makeFormatFn("span"))
	te.bind(sz.NameSymFormatStrong, 1, te.makeFormatFn("strong"))
	te.bind(sz.NameSymFormatSub, 1, te.makeFormatFn("sub"))
	te.bind(sz.NameSymFormatSuper, 1, te.makeFormatFn("sup"))
	ev.bind(sz.SymFormatDelete, 1, ev.makeFormatFn(symDEL))
	ev.bind(sz.SymFormatEmph, 1, ev.makeFormatFn(symEM))
	ev.bind(sz.SymFormatInsert, 1, ev.makeFormatFn(symINS))
	ev.bind(sz.SymFormatMark, 1, ev.makeFormatFn(symMARK))
	ev.bind(sz.SymFormatQuote, 1, ev.evalQuote)
	ev.bind(sz.SymFormatSpan, 1, ev.makeFormatFn(SymSPAN))
	ev.bind(sz.SymFormatStrong, 1, ev.makeFormatFn(SymSTRONG))
	ev.bind(sz.SymFormatSub, 1, ev.makeFormatFn(symSUB))
	ev.bind(sz.SymFormatSuper, 1, ev.makeFormatFn(symSUP))

	te.bind(sz.NameSymLiteralComment, 1, func(args []sx.Object) sx.Object {
		if te.getAttributes(args[0]).HasDefault() {
	ev.bind(sz.SymLiteralComment, 1, func(args sx.Vector, env *Environment) sx.Object {
		if GetAttributes(args[0], env).HasDefault() {
			if len(args) > 1 {
				if s := te.getString(args[1]); s != "" {
					return sx.Nil().Cons(s).Cons(te.Make(sxhtml.NameSymInlineComment))
				if s := getString(ev.Eval(args[1], env), env); s.GetValue() != "" {
					return sx.Nil().Cons(s).Cons(sxhtml.SymInlineComment)
				}
			}
		}
		return sx.Nil()
	})
	te.bind(sz.NameSymLiteralHTML, 2, te.transformHTML)
	ev.bind(sz.SymLiteralHTML, 2, ev.evalHTML)
	kbdSym := te.Make("kbd")
	te.bind(sz.NameSymLiteralInput, 2, func(args []sx.Object) sx.Object {
		return te.transformLiteral(args, nil, kbdSym)
	ev.bind(sz.SymLiteralInput, 2, func(args sx.Vector, env *Environment) sx.Object {
		return evalLiteral(args, nil, symKBD, env)
	})
	codeSym := te.Make("code")
	te.bind(sz.NameSymLiteralMath, 2, func(args []sx.Object) sx.Object {
		a := te.getAttributes(args[0]).AddClass("zs-math")
		return te.transformLiteral(args, a, codeSym)
	ev.bind(sz.SymLiteralMath, 2, func(args sx.Vector, env *Environment) sx.Object {
		a := GetAttributes(args[0], env).AddClass("zs-math")
		return evalLiteral(args, a, symCODE, env)
	})
	sampSym := te.Make("samp")
	te.bind(sz.NameSymLiteralOutput, 2, func(args []sx.Object) sx.Object {
		return te.transformLiteral(args, nil, sampSym)
	ev.bind(sz.SymLiteralOutput, 2, func(args sx.Vector, env *Environment) sx.Object {
		return evalLiteral(args, nil, symSAMP, env)
	})
	te.bind(sz.NameSymLiteralProg, 2, func(args []sx.Object) sx.Object {
		return te.transformLiteral(args, nil, codeSym)
	ev.bind(sz.SymLiteralProg, 2, func(args sx.Vector, env *Environment) sx.Object {
		return evalLiteral(args, nil, symCODE, env)
	})

	ev.bind(sz.SymLiteralZettel, 0, nilFn)
}


	te.bind(sz.NameSymLiteralZettel, 0, func([]sx.Object) sx.Object { return sx.Nil() })
func (ev *Evaluator) makeFormatFn(sym *sx.Symbol) EvalFn {
	return func(args sx.Vector, env *Environment) sx.Object {
}

		a := GetAttributes(args[0], env)
func (te *TransformEnv) makeFormatFn(tag string) transformFn {
	sym := te.Make(tag)
		env.pushAttributes(a)
	return func(args []sx.Object) sx.Object {
		a := te.getAttributes(args[0])
		if val, found := a.Get(""); found {
		defer env.popAttributes()
		if val, hasClass := a.Get(""); hasClass {
			a = a.Remove("").AddClass(val)
		}
		res := sx.MakeList(args[1:]...)
		res := ev.evalSlice(args[1:], env)
		if len(a) > 0 {
			res = res.Cons(te.transformAttribute(a))
			res = res.Cons(EvaluateAttrbute(a))
		}
		return res.Cons(sym)
	}
}
func (te *TransformEnv) transformQuote(args []sx.Object) sx.Object {
	const langAttr = "lang"
	a := te.getAttributes(args[0])

func (ev *Evaluator) evalQuote(args sx.Vector, env *Environment) sx.Object {
	a := GetAttributes(args[0], env)
	env.pushAttributes(a)
	defer env.popAttributes()
	langVal, found := a.Get(langAttr)
	if found {
		a = a.Remove(langAttr)
	}
	if val, found2 := a.Get(""); found2 {

	if val, hasClass := a.Get(""); hasClass {
		a = a.Remove("").AddClass(val)
	}
	leftQ, rightQ, withNbsp := env.getQuotes()
	res := sx.MakeList(args[1:]...)
	if len(a) > 0 {
		res = res.Cons(te.transformAttribute(a))
	}
	res = res.Cons(te.Make("q"))

	env.quoteNesting++
	res := ev.evalSlice(args[1:], env)
	env.quoteNesting--

	lastPair := res.LastPair()
	if lastPair.IsNil() {
		res = sx.Cons(sx.MakeList(sxhtml.SymNoEscape, sx.MakeString(leftQ), sx.MakeString(rightQ)), sx.Nil())
	} else {
		if withNbsp {
			lastPair.AppendBang(sx.MakeList(sxhtml.SymNoEscape, sx.MakeString("&nbsp;"), sx.MakeString(rightQ)))
			res = res.Cons(sx.MakeList(sxhtml.SymNoEscape, sx.MakeString(leftQ), sx.MakeString("&nbsp;")))
		} else {
			lastPair.AppendBang(sx.MakeList(sxhtml.SymNoEscape, sx.MakeString(rightQ)))
			res = res.Cons(sx.MakeList(sxhtml.SymNoEscape, sx.MakeString(leftQ)))
		}
	}
	if len(a) > 0 {
		res = res.Cons(EvaluateAttrbute(a))
	if found {
		res = sx.Nil().Cons(res).Cons(te.transformAttribute(attrs.Attributes{}.Set(langAttr, langVal))).Cons(te.symSpan)
		return res.Cons(SymSPAN)
	}
	return res
	return res.Cons(sxhtml.SymListSplice)
}

var visibleReplacer = strings.NewReplacer(" ", "\u2423")

func (te *TransformEnv) transformLiteral(args []sx.Object, a attrs.Attributes, sym *sx.Symbol) sx.Object {
func evalLiteral(args sx.Vector, a attrs.Attributes, sym *sx.Symbol, env *Environment) sx.Object {
	if a == nil {
		a = te.getAttributes(args[0])
		a = GetAttributes(args[0], env)
	}
	a = setProgLang(a)
	literal := te.getString(args[1]).String()
	literal := getString(args[1], env).GetValue()
	if a.HasDefault() {
		a = a.RemoveDefault()
		literal = visibleReplacer.Replace(literal)
	}
	res := sx.Nil().Cons(sx.MakeString(literal))
	if len(a) > 0 {
		res = res.Cons(te.transformAttribute(a))
		res = res.Cons(EvaluateAttrbute(a))
	}
	return res.Cons(sym)
}

func setProgLang(a attrs.Attributes) attrs.Attributes {
	if val, found := a.Get(""); found {
		a = a.AddClass("language-" + val).Remove("")
	}
	return a
}

func (te *TransformEnv) transformHTML(args []sx.Object) sx.Object {
	if s := te.getString(args[1]); s != "" && IsSafe(s.String()) {
		return sx.Nil().Cons(s).Cons(te.symNoEscape)
func (ev *Evaluator) evalHTML(args sx.Vector, env *Environment) sx.Object {
	if s := getString(ev.Eval(args[1], env), env); s.GetValue() != "" && IsSafe(s.GetValue()) {
		return sx.Nil().Cons(s).Cons(sxhtml.SymNoEscape)
	}
	return nil
}

func (te *TransformEnv) transformBLOB(description *sx.Pair, syntax, data sx.String) sx.Object {
	if data == "" {
func evalBLOB(description *sx.Pair, syntax, data sx.String) sx.Object {
	if data.GetValue() == "" {
		return sx.Nil()
	}
	switch syntax {
	switch syntax.GetValue() {
	case "":
		return sx.Nil()
	case api.ValueSyntaxSVG:
		return sx.Nil().Cons(sx.Nil().Cons(data).Cons(te.symNoEscape)).Cons(te.symP)
		return sx.Nil().Cons(sx.Nil().Cons(data).Cons(sxhtml.SymNoEscape)).Cons(SymP)
	default:
		imgAttr := sx.Nil().Cons(sx.Cons(te.Make("src"), sx.MakeString("data:image/"+syntax.String()+";base64,"+data.String())))
		imgAttr := sx.Nil().Cons(sx.Cons(SymAttrSrc, sx.MakeString("data:image/"+syntax.GetValue()+";base64,"+data.GetValue())))
		var sb strings.Builder
		te.flattenText(&sb, description)
		flattenText(&sb, description)
		if d := sb.String(); d != "" {
			imgAttr = imgAttr.Cons(sx.Cons(te.Make("alt"), sx.MakeString(d)))
			imgAttr = imgAttr.Cons(sx.Cons(symAttrAlt, sx.MakeString(d)))
		}
		return sx.Nil().Cons(sx.Nil().Cons(imgAttr.Cons(sxhtml.SymAttr)).Cons(SymIMG)).Cons(SymP)
	}
}

func flattenText(sb *strings.Builder, lst *sx.Pair) {
	for elem := lst; elem != nil; elem = elem.Tail() {
		switch obj := elem.Car().(type) {
		case sx.String:
			sb.WriteString(obj.GetValue())
		case *sx.Pair:
			flattenText(sb, obj)
		}
		return sx.Nil().Cons(sx.Nil().Cons(imgAttr.Cons(te.symAttr)).Cons(te.Make("img"))).Cons(te.symP)
	}
}

func (ev *Evaluator) evalList(args sx.Vector, env *Environment) sx.Object {
	return ev.evalSlice(args, env)
}
func nilFn(sx.Vector, *Environment) sx.Object { return sx.Nil() }
func (te *TransformEnv) flattenText(sb *strings.Builder, lst *sx.Pair) {
	for elem := lst; elem != nil; elem = elem.Tail() {

// Eval evaluates an object in an environment.
func (ev *Evaluator) Eval(obj sx.Object, env *Environment) sx.Object {
	if env.err != nil {
		switch obj := elem.Car().(type) {
		case sx.String:
		return sx.Nil()
			sb.WriteString(obj.String())
		case *sx.Pair:
			te.flattenText(sb, obj)
		}
	}
	if sx.IsNil(obj) {
		return obj
	}
	lst, isLst := sx.GetPair(obj)
	if !isLst {
		return obj
	}
	sym, found := sx.GetSymbol(lst.Car())
	if !found {
		env.err = fmt.Errorf("symbol expected, but got %T/%v", lst.Car(), lst.Car())
		return sx.Nil()
}

type transformFn func([]sx.Object) sx.Object

	}
	symVal := sym.GetValue()
	fn, found := ev.fns[symVal]
	if !found {
		env.err = fmt.Errorf("symbol %q not bound", sym)
		return sx.Nil()
	}
	var args sx.Vector
	for cdr := lst.Cdr(); !sx.IsNil(cdr); {
		pair, isPair := sx.GetPair(cdr)
		if !isPair {
			break
		}
func (te *TransformEnv) bind(name string, minArity int, fn transformFn) {
	te.astEnv.Bind(te.astSF.MustMake(name), sxeval.BuiltinA(func(args []sx.Object) (sx.Object, error) {
		if nArgs := len(args); nArgs < minArity {
			return sx.Nil(), fmt.Errorf("not enough arguments (%d) for form %v (%d)", nArgs, name, minArity)
		args = append(args, pair.Car())
		cdr = pair.Cdr()
	}
	if minArgs, hasMinArgs := ev.minArgs[symVal]; hasMinArgs {
		if minArgs > len(args) {
			env.err = fmt.Errorf("%v needs at least %d arguments, but got only %d", sym, minArgs, len(args))
			return sx.Nil()
		}
	}
		res := fn(args)
		return res, te.err
	result := fn(args, env)
	if env.err != nil {
		return sx.Nil()
	}
	return result
	}))
}

func (te *TransformEnv) Rebind(name string, fn func([]sx.Object, sxeval.Callable) sx.Object) {
	sym := te.astSF.MustMake(name)
	obj, found := te.astEnv.Lookup(sym)
func (ev *Evaluator) evalSlice(args sx.Vector, env *Environment) *sx.Pair {
	var result sx.ListBuilder
	for _, arg := range args {
		elem := ev.Eval(arg, env)
	if !found {
		panic(sym.String())
		result.Add(elem)
	}
	preFn, ok := sxeval.GetCallable(obj)
	if !ok {
	if env.err == nil {
		panic(sym.String())
		return result.List()
	}
	te.astEnv.Bind(sym, sxeval.BuiltinA(func(args []sx.Object) (sx.Object, error) {
		res := fn(args, preFn)
		return res, te.err
	return nil
	}))
}

// EvaluatePairList evaluates a list of lists.
func (ev *Evaluator) EvalPairList(pair *sx.Pair, env *Environment) *sx.Pair {
	var result sx.ListBuilder
	for node := pair; node != nil; node = node.Tail() {
		elem := ev.Eval(node.Car(), env)
		result.Add(elem)

	}
func (te *TransformEnv) Make(name string) *sx.Symbol { return te.tr.Make(name) }
func (te *TransformEnv) getSymbol(val sx.Object) *sx.Symbol {
	if te.err != nil {
		return nil
	}
	if sym, ok := sx.GetSymbol(val); ok {
		return sym
	}
	te.err = fmt.Errorf("%v/%T is not a symbol", val, val)
	return nil
	if env.err == nil {
		return result.List()
	}
	return nil
}

func (ev *Evaluator) evalLink(a attrs.Attributes, refValue sx.String, inline sx.Vector, env *Environment) sx.Object {
	result := ev.evalSlice(inline, env)
	if len(inline) == 0 {
		result = sx.Nil().Cons(refValue)
	}
	if ev.noLinks {
		return result.Cons(SymSPAN)
	}
	return result.Cons(EvaluateAttrbute(a)).Cons(SymA)
}

func getSymbol(obj sx.Object, env *Environment) *sx.Symbol {
	if env.err == nil {
		if sym, ok := sx.GetSymbol(obj); ok {
			return sym
		}
		env.err = fmt.Errorf("%v/%T is not a symbol", obj, obj)
	}
	return sx.MakeSymbol("???")
}
func (te *TransformEnv) getString(val sx.Object) sx.String {
	if te.err != nil {
		return ""
func getString(val sx.Object, env *Environment) sx.String {
	if env.err != nil {
		return sx.String{}
	}
	if s, ok := sx.GetString(val); ok {
		return s
	}
	te.err = fmt.Errorf("%v/%T is not a string", val, val)
	return ""
	env.err = fmt.Errorf("%v/%T is not a string", val, val)
	return sx.String{}
}
func (te *TransformEnv) getInt64(val sx.Object) int64 {
	if te.err != nil {
		return -1017
	}
	if num, ok := sx.GetNumber(val); ok {
		return int64(num.(sx.Int64))
	}
	te.err = fmt.Errorf("%v/%T is not a number", val, val)
	return -1017
}
func (te *TransformEnv) getList(val sx.Object) *sx.Pair {
	if te.err == nil {
func getList(val sx.Object, env *Environment) *sx.Pair {
	if env.err == nil {
		if res, isPair := sx.GetPair(val); isPair {
			return res
		}
		te.err = fmt.Errorf("%v/%T is not a list", val, val)
		env.err = fmt.Errorf("%v/%T is not a list", val, val)
	}
	return nil
}
func (te *TransformEnv) getAttributes(args sx.Object) attrs.Attributes {
	return sz.GetAttributes(te.getList(args))
}

func getInt64(val sx.Object, env *Environment) int64 {
	if env.err != nil {
		return -1017
	}
	if num, ok := sx.GetNumber(val); ok {
func (te *TransformEnv) transformLink(a attrs.Attributes, refValue sx.String, inline []sx.Object) sx.Object {
	result := sx.MakeList(inline...)
		return int64(num.(sx.Int64))
	if len(inline) == 0 {
		result = sx.Nil().Cons(refValue)
	}
	if te.tr.noLinks {
		return result.Cons(te.symSpan)
	}
	env.err = fmt.Errorf("%v/%T is not a number", val, val)
	return -1017
}
	return result.Cons(te.transformAttribute(a)).Cons(te.symA)
}

func (te *TransformEnv) transformAttribute(a attrs.Attributes) *sx.Pair {

// GetAttributes evaluates the given arg in the given environment and returns
// the contained attributes.
	return te.tr.TransformAttrbute(a)
}

func GetAttributes(arg sx.Object, env *Environment) attrs.Attributes {
func (te *TransformEnv) transformMeta(a attrs.Attributes) *sx.Pair {
	return te.tr.TransformMeta(a)
	return sz.GetAttributes(getList(arg, env))
}

var unsafeSnippets = []string{
	"<script", "</script",
	"<iframe", "</iframe",
}

//-----------------------------------------------------------------------------
// Copyright (c) 2022-present Detlef Stern
//
// This file is part of zettelstore-client.
//
// Zettelstore client is licensed under the latest version of the EUPL
// (European Union Public License). Please see file LICENSE.txt for your rights
// and obligations under this license.
//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2022-present Detlef Stern
//-----------------------------------------------------------------------------

package sz

import "zettelstore.de/sx.fossil"
import "t73f.de/r/sx"

// Various constants for Zettel data. Some of them are technically variables.

const (
var (
	// Symbols for Metanodes
	NameSymBlock  = "BLOCK"
	NameSymInline = "INLINE"
	SymBlock  = sx.MakeSymbol("BLOCK")
	SymInline = sx.MakeSymbol("INLINE")
	NameSymList   = "list"
	NameSymMeta   = "META"
	SymMeta   = sx.MakeSymbol("META")
	NameSymQuote  = "quote"

	// Symbols for Zettel node types.
	NameSymBLOB            = "BLOB"
	NameSymCell            = "CELL"
	NameSymCellCenter      = "CELL-CENTER"
	NameSymCellLeft        = "CELL-LEFT"
	// Symbols for Zettel noMakede types.
	SymBLOB            = sx.MakeSymbol("BLOB")
	SymCell            = sx.MakeSymbol("CELL")
	SymCellCenter      = sx.MakeSymbol("CELL-CENTER")
	SymCellLeft        = sx.MakeSymbol("CELL-LEFT")
	NameSymCellRight       = "CELL-RIGHT"
	NameSymCite            = "CITE"
	NameSymDescription     = "DESCRIPTION"
	NameSymEmbed           = "EMBED"
	NameSymEmbedBLOB       = "EMBED-BLOB"
	NameSymEndnote         = "ENDNOTE"
	NameSymFormatEmph      = "FORMAT-EMPH"
	NameSymFormatDelete    = "FORMAT-DELETE"
	NameSymFormatInsert    = "FORMAT-INSERT"
	NameSymFormatQuote     = "FORMAT-QUOTE"
	NameSymFormatSpan      = "FORMAT-SPAN"
	NameSymFormatSub       = "FORMAT-SUB"
	NameSymFormatSuper     = "FORMAT-SUPER"
	NameSymFormatStrong    = "FORMAT-STRONG"
	NameSymHard            = "HARD"
	NameSymHeading         = "HEADING"
	NameSymLinkInvalid     = "LINK-INVALID"
	NameSymLinkZettel      = "LINK-ZETTEL"
	NameSymLinkSelf        = "LINK-SELF"
	NameSymLinkFound       = "LINK-FOUND"
	NameSymLinkBroken      = "LINK-BROKEN"
	NameSymLinkHosted      = "LINK-HOSTED"
	NameSymLinkBased       = "LINK-BASED"
	SymCellRight       = sx.MakeSymbol("CELL-RIGHT")
	NameSymLinkQuery       = "LINK-QUERY"
	NameSymLinkExternal    = "LINK-EXTERNAL"
	NameSymListOrdered     = "ORDERED"
	NameSymListUnordered   = "UNORDERED"
	NameSymListQuote       = "QUOTATION"
	NameSymLiteralProg     = "LITERAL-CODE"
	NameSymLiteralComment  = "LITERAL-COMMENT"
	NameSymLiteralHTML     = "LITERAL-HTML"
	NameSymLiteralInput    = "LITERAL-INPUT"
	NameSymLiteralMath     = "LITERAL-MATH"
	NameSymLiteralOutput   = "LITERAL-OUTPUT"
	NameSymLiteralZettel   = "LITERAL-ZETTEL"
	NameSymMark            = "MARK"
	NameSymPara            = "PARA"
	SymCite            = sx.MakeSymbol("CITE")
	SymDescription     = sx.MakeSymbol("DESCRIPTION")
	NameSymRegionBlock     = "REGION-BLOCK"
	NameSymRegionQuote     = "REGION-QUOTE"
	NameSymRegionVerse     = "REGION-VERSE"
	NameSymSoft            = "SOFT"
	NameSymSpace           = "SPACE"
	NameSymTable           = "TABLE"
	NameSymText            = "TEXT"
	NameSymThematic        = "THEMATIC"
	NameSymTransclude      = "TRANSCLUDE"
	NameSymUnknown         = "UNKNOWN-NODE"
	SymEmbed           = sx.MakeSymbol("EMBED")
	SymEmbedBLOB       = sx.MakeSymbol("EMBED-BLOB")
	SymEndnote         = sx.MakeSymbol("ENDNOTE")
	SymFormatEmph      = sx.MakeSymbol("FORMAT-EMPH")
	SymFormatDelete    = sx.MakeSymbol("FORMAT-DELETE")
	SymFormatInsert    = sx.MakeSymbol("FORMAT-INSERT")
	SymFormatMark      = sx.MakeSymbol("FORMAT-MARK")
	NameSymVerbatimComment = "VERBATIM-COMMENT"
	NameSymVerbatimEval    = "VERBATIM-EVAL"
	NameSymVerbatimHTML    = "VERBATIM-HTML"
	NameSymVerbatimMath    = "VERBATIM-MATH"
	NameSymVerbatimProg    = "VERBATIM-CODE"
	NameSymVerbatimZettel  = "VERBATIM-ZETTEL"

	SymFormatQuote     = sx.MakeSymbol("FORMAT-QUOTE")
	// Constant symbols for reference states.
	NameSymRefStateInvalid  = "INVALID"
	NameSymRefStateZettel   = "ZETTEL"
	NameSymRefStateSelf     = "SELF"
	NameSymRefStateFound    = "FOUND"
	SymFormatSpan      = sx.MakeSymbol("FORMAT-SPAN")
	SymFormatSub       = sx.MakeSymbol("FORMAT-SUB")
	NameSymRefStateBroken   = "BROKEN"
	NameSymRefStateHosted   = "HOSTED"
	NameSymRefStateBased    = "BASED"
	SymFormatSuper     = sx.MakeSymbol("FORMAT-SUPER")
	NameSymRefStateQuery    = "QUERY"
	NameSymRefStateExternal = "EXTERNAL"

	SymFormatStrong    = sx.MakeSymbol("FORMAT-STRONG")
	// Symbols for metadata types.
	NameSymTypeCredential   = "CREDENTIAL"
	NameSymTypeEmpty        = "EMPTY-STRING"
	NameSymTypeID           = "ZID"
	SymHard            = sx.MakeSymbol("HARD")
	NameSymTypeIDSet        = "ZID-SET"
	NameSymTypeNumber       = "NUMBER"
	NameSymTypeString       = "STRING"
	NameSymTypeTagSet       = "TAG-SET"
	SymHeading         = sx.MakeSymbol("HEADING")
	SymLinkInvalid     = sx.MakeSymbol("LINK-INVALID")
	NameSymTypeTimestamp    = "TIMESTAMP"
	NameSymTypeURL          = "URL"
	NameSymTypeWord         = "WORD"
	SymLinkZettel      = sx.MakeSymbol("LINK-ZETTEL")
	SymLinkSelf        = sx.MakeSymbol("LINK-SELF")
	NameSymTypeWordSet      = "WORD-SET"
	NameSymTypeZettelmarkup = "ZETTELMARKUP"
)

	SymLinkFound       = sx.MakeSymbol("LINK-FOUND")
// ZettelSymbols collect all symbols needed to represent zettel data.
type ZettelSymbols struct {
	// Symbols for Metanodes
	SymBlock  *sx.Symbol
	SymInline *sx.Symbol
	SymList   *sx.Symbol
	SymMeta   *sx.Symbol
	SymQuote  *sx.Symbol

	SymLinkBroken      = sx.MakeSymbol("LINK-BROKEN")
	// Symbols for Zettel node types.
	SymBLOB            *sx.Symbol
	SymCell            *sx.Symbol
	SymCellCenter      *sx.Symbol
	SymCellLeft        *sx.Symbol
	SymCellRight       *sx.Symbol
	SymCite            *sx.Symbol
	SymDescription     *sx.Symbol
	SymEmbed           *sx.Symbol
	SymEmbedBLOB       *sx.Symbol
	SymEndnote         *sx.Symbol
	SymFormatEmph      *sx.Symbol
	SymFormatDelete    *sx.Symbol
	SymFormatInsert    *sx.Symbol
	SymFormatQuote     *sx.Symbol
	SymFormatSpan      *sx.Symbol
	SymFormatSub       *sx.Symbol
	SymFormatSuper     *sx.Symbol
	SymFormatStrong    *sx.Symbol
	SymHard            *sx.Symbol
	SymHeading         *sx.Symbol
	SymLinkInvalid     *sx.Symbol
	SymLinkZettel      *sx.Symbol
	SymLinkSelf        *sx.Symbol
	SymLinkFound       *sx.Symbol
	SymLinkBroken      *sx.Symbol
	SymLinkHosted      *sx.Symbol
	SymLinkBased       *sx.Symbol
	SymLinkQuery       *sx.Symbol
	SymLinkExternal    *sx.Symbol
	SymListOrdered     *sx.Symbol
	SymListUnordered   *sx.Symbol
	SymListQuote       *sx.Symbol
	SymLiteralProg     *sx.Symbol
	SymLiteralComment  *sx.Symbol
	SymLiteralHTML     *sx.Symbol
	SymLiteralInput    *sx.Symbol
	SymLiteralMath     *sx.Symbol
	SymLiteralOutput   *sx.Symbol
	SymLiteralZettel   *sx.Symbol
	SymMark            *sx.Symbol
	SymPara            *sx.Symbol
	SymRegionBlock     *sx.Symbol
	SymRegionQuote     *sx.Symbol
	SymRegionVerse     *sx.Symbol
	SymSoft            *sx.Symbol
	SymLinkHosted      = sx.MakeSymbol("LINK-HOSTED")
	SymLinkBased       = sx.MakeSymbol("LINK-BASED")
	SymLinkQuery       = sx.MakeSymbol("LINK-QUERY")
	SymLinkExternal    = sx.MakeSymbol("LINK-EXTERNAL")
	SymListOrdered     = sx.MakeSymbol("ORDERED")
	SymListUnordered   = sx.MakeSymbol("UNORDERED")
	SymListQuote       = sx.MakeSymbol("QUOTATION")
	SymLiteralProg     = sx.MakeSymbol("LITERAL-CODE")
	SymLiteralComment  = sx.MakeSymbol("LITERAL-COMMENT")
	SymLiteralHTML     = sx.MakeSymbol("LITERAL-HTML")
	SymLiteralInput    = sx.MakeSymbol("LITERAL-INPUT")
	SymLiteralMath     = sx.MakeSymbol("LITERAL-MATH")
	SymLiteralOutput   = sx.MakeSymbol("LITERAL-OUTPUT")
	SymLiteralZettel   = sx.MakeSymbol("LITERAL-ZETTEL")
	SymMark            = sx.MakeSymbol("MARK")
	SymPara            = sx.MakeSymbol("PARA")
	SymRegionBlock     = sx.MakeSymbol("REGION-BLOCK")
	SymRegionQuote     = sx.MakeSymbol("REGION-QUOTE")
	SymRegionVerse     = sx.MakeSymbol("REGION-VERSE")
	SymSoft            = sx.MakeSymbol("SOFT")
	SymSpace           *sx.Symbol
	SymTable           *sx.Symbol
	SymTable           = sx.MakeSymbol("TABLE")
	SymText            *sx.Symbol
	SymThematic        *sx.Symbol
	SymTransclude      *sx.Symbol
	SymUnknown         *sx.Symbol
	SymVerbatimComment *sx.Symbol
	SymVerbatimEval    *sx.Symbol
	SymVerbatimHTML    *sx.Symbol
	SymVerbatimMath    *sx.Symbol
	SymVerbatimProg    *sx.Symbol
	SymVerbatimZettel  *sx.Symbol

	// Constant symbols for reference states.

	SymRefStateInvalid  *sx.Symbol
	SymRefStateZettel   *sx.Symbol
	SymRefStateSelf     *sx.Symbol
	SymRefStateFound    *sx.Symbol
	SymRefStateBroken   *sx.Symbol
	SymRefStateHosted   *sx.Symbol
	SymRefStateBased    *sx.Symbol
	SymRefStateQuery    *sx.Symbol
	SymRefStateExternal *sx.Symbol

	// Symbols for metadata types

	SymTypeCredential   *sx.Symbol
	SymTypeEmpty        *sx.Symbol
	SymTypeID           *sx.Symbol
	SymTypeIDSet        *sx.Symbol
	SymTypeNumber       *sx.Symbol
	SymText            = sx.MakeSymbol("TEXT")
	SymThematic        = sx.MakeSymbol("THEMATIC")
	SymTransclude      = sx.MakeSymbol("TRANSCLUDE")
	SymTypeString       *sx.Symbol
	SymTypeTagSet       *sx.Symbol
	SymTypeTimestamp    *sx.Symbol
	SymTypeURL          *sx.Symbol
	SymTypeWord         *sx.Symbol
	SymUnknown         = sx.MakeSymbol("UNKNOWN-NODE")
	SymVerbatimComment = sx.MakeSymbol("VERBATIM-COMMENT")
	SymTypeWordSet      *sx.Symbol
	SymTypeZettelmarkup *sx.Symbol
	SymVerbatimEval    = sx.MakeSymbol("VERBATIM-EVAL")
}

	SymVerbatimHTML    = sx.MakeSymbol("VERBATIM-HTML")
func (zs *ZettelSymbols) InitializeZettelSymbols(sf sx.SymbolFactory) {
	// Symbols for Metanodes
	SymVerbatimMath    = sx.MakeSymbol("VERBATIM-MATH")
	zs.SymBlock = sf.MustMake(NameSymBlock)
	zs.SymInline = sf.MustMake(NameSymInline)
	zs.SymList = sf.MustMake(NameSymList)
	zs.SymMeta = sf.MustMake(NameSymMeta)
	zs.SymQuote = sf.MustMake(NameSymQuote)

	// Symbols for Zettel node types.
	SymVerbatimProg    = sx.MakeSymbol("VERBATIM-CODE")
	SymVerbatimZettel  = sx.MakeSymbol("VERBATIM-ZETTEL")
	zs.SymBLOB = sf.MustMake(NameSymBLOB)
	zs.SymCell = sf.MustMake(NameSymCell)
	zs.SymCellCenter = sf.MustMake(NameSymCellCenter)
	zs.SymCellLeft = sf.MustMake(NameSymCellLeft)
	zs.SymCellRight = sf.MustMake(NameSymCellRight)
	zs.SymCite = sf.MustMake(NameSymCite)
	zs.SymDescription = sf.MustMake(NameSymDescription)
	zs.SymEmbed = sf.MustMake(NameSymEmbed)
	zs.SymEmbedBLOB = sf.MustMake(NameSymEmbedBLOB)
	zs.SymEndnote = sf.MustMake(NameSymEndnote)
	zs.SymFormatEmph = sf.MustMake(NameSymFormatEmph)
	zs.SymFormatDelete = sf.MustMake(NameSymFormatDelete)
	zs.SymFormatInsert = sf.MustMake(NameSymFormatInsert)
	zs.SymFormatQuote = sf.MustMake(NameSymFormatQuote)

	// Constant symbols for reference states.
	zs.SymFormatSpan = sf.MustMake(NameSymFormatSpan)
	zs.SymFormatSub = sf.MustMake(NameSymFormatSub)
	zs.SymFormatSuper = sf.MustMake(NameSymFormatSuper)
	zs.SymFormatStrong = sf.MustMake(NameSymFormatStrong)
	zs.SymHard = sf.MustMake(NameSymHard)
	zs.SymHeading = sf.MustMake(NameSymHeading)
	zs.SymLinkInvalid = sf.MustMake(NameSymLinkInvalid)
	zs.SymLinkZettel = sf.MustMake(NameSymLinkZettel)
	SymRefStateInvalid  = sx.MakeSymbol("INVALID")
	SymRefStateZettel   = sx.MakeSymbol("ZETTEL")
	zs.SymLinkSelf = sf.MustMake(NameSymLinkSelf)
	zs.SymLinkFound = sf.MustMake(NameSymLinkFound)
	zs.SymLinkBroken = sf.MustMake(NameSymLinkBroken)
	zs.SymLinkHosted = sf.MustMake(NameSymLinkHosted)
	zs.SymLinkBased = sf.MustMake(NameSymLinkBased)
	zs.SymLinkQuery = sf.MustMake(NameSymLinkQuery)
	zs.SymLinkExternal = sf.MustMake(NameSymLinkExternal)
	SymRefStateSelf     = sx.MakeSymbol("SELF")
	SymRefStateFound    = sx.MakeSymbol("FOUND")
	SymRefStateBroken   = sx.MakeSymbol("BROKEN")
	SymRefStateHosted   = sx.MakeSymbol("HOSTED")
	SymRefStateBased    = sx.MakeSymbol("BASED")
	SymRefStateQuery    = sx.MakeSymbol("QUERY")
	SymRefStateExternal = sx.MakeSymbol("EXTERNAL")
	zs.SymListOrdered = sf.MustMake(NameSymListOrdered)
	zs.SymListUnordered = sf.MustMake(NameSymListUnordered)
	zs.SymListQuote = sf.MustMake(NameSymListQuote)
	zs.SymLiteralProg = sf.MustMake(NameSymLiteralProg)
	zs.SymLiteralComment = sf.MustMake(NameSymLiteralComment)
	zs.SymLiteralHTML = sf.MustMake(NameSymLiteralHTML)
	zs.SymLiteralInput = sf.MustMake(NameSymLiteralInput)
	zs.SymLiteralMath = sf.MustMake(NameSymLiteralMath)
	zs.SymLiteralOutput = sf.MustMake(NameSymLiteralOutput)
	zs.SymLiteralZettel = sf.MustMake(NameSymLiteralZettel)
	zs.SymMark = sf.MustMake(NameSymMark)
	zs.SymPara = sf.MustMake(NameSymPara)
	zs.SymRegionBlock = sf.MustMake(NameSymRegionBlock)
	zs.SymRegionQuote = sf.MustMake(NameSymRegionQuote)
	zs.SymRegionVerse = sf.MustMake(NameSymRegionVerse)
	zs.SymSoft = sf.MustMake(NameSymSoft)
	zs.SymSpace = sf.MustMake(NameSymSpace)
	zs.SymTable = sf.MustMake(NameSymTable)
	zs.SymText = sf.MustMake(NameSymText)
	zs.SymThematic = sf.MustMake(NameSymThematic)
	zs.SymTransclude = sf.MustMake(NameSymTransclude)
	zs.SymUnknown = sf.MustMake(NameSymUnknown)
	zs.SymVerbatimComment = sf.MustMake(NameSymVerbatimComment)
	zs.SymVerbatimEval = sf.MustMake(NameSymVerbatimEval)
	zs.SymVerbatimHTML = sf.MustMake(NameSymVerbatimHTML)
	zs.SymVerbatimMath = sf.MustMake(NameSymVerbatimMath)
	zs.SymVerbatimProg = sf.MustMake(NameSymVerbatimProg)
	zs.SymVerbatimZettel = sf.MustMake(NameSymVerbatimZettel)

	// Constant symbols for reference states.
	zs.SymRefStateInvalid = sf.MustMake(NameSymRefStateInvalid)
	zs.SymRefStateZettel = sf.MustMake(NameSymRefStateZettel)
	zs.SymRefStateSelf = sf.MustMake(NameSymRefStateSelf)
	zs.SymRefStateFound = sf.MustMake(NameSymRefStateFound)
	zs.SymRefStateBroken = sf.MustMake(NameSymRefStateBroken)
	zs.SymRefStateHosted = sf.MustMake(NameSymRefStateHosted)
	zs.SymRefStateBased = sf.MustMake(NameSymRefStateBased)
	zs.SymRefStateQuery = sf.MustMake(NameSymRefStateQuery)
	zs.SymRefStateExternal = sf.MustMake(NameSymRefStateExternal)

	// Symbols for metadata types.
	zs.SymTypeCredential = sf.MustMake(NameSymTypeCredential)
	zs.SymTypeEmpty = sf.MustMake(NameSymTypeEmpty)
	zs.SymTypeID = sf.MustMake(NameSymTypeID)
	zs.SymTypeIDSet = sf.MustMake(NameSymTypeIDSet)
	zs.SymTypeNumber = sf.MustMake(NameSymTypeNumber)
	zs.SymTypeString = sf.MustMake(NameSymTypeString)
	zs.SymTypeTagSet = sf.MustMake(NameSymTypeTagSet)
	zs.SymTypeTimestamp = sf.MustMake(NameSymTypeTimestamp)
	zs.SymTypeURL = sf.MustMake(NameSymTypeURL)
	zs.SymTypeWord = sf.MustMake(NameSymTypeWord)
	SymTypeCredential   = sx.MakeSymbol("CREDENTIAL")
	SymTypeEmpty        = sx.MakeSymbol("EMPTY-STRING")
	SymTypeID           = sx.MakeSymbol("ZID")
	SymTypeIDSet        = sx.MakeSymbol("ZID-SET")
	SymTypeNumber       = sx.MakeSymbol("NUMBER")
	SymTypeString       = sx.MakeSymbol("STRING")
	SymTypeTagSet       = sx.MakeSymbol("TAG-SET")
	SymTypeTimestamp    = sx.MakeSymbol("TIMESTAMP")
	SymTypeURL          = sx.MakeSymbol("URL")
	SymTypeWord         = sx.MakeSymbol("WORD")
	zs.SymTypeWordSet = sf.MustMake(NameSymTypeWordSet)
	zs.SymTypeZettelmarkup = sf.MustMake(NameSymTypeZettelmarkup)
	SymTypeZettelmarkup = sx.MakeSymbol("ZETTELMARKUP")
}
)