gradually, one major focus is a long-term store of these notes, hence the name
“Zettelstore”.

To get an initial impression, take a look at the
[manual](https://zettelstore.de/manual/). It is a live example of the
zettelstore software, running in read-only mode.

[Zettelstore Client](https://t73f.de/r/zsc) provides client software to access
Zettelstore via its API more easily, [Zettelstore
Contrib](https://zettelstore.de/contrib) contains contributed software, which
often connects to Zettelstore via its API. Some of the software packages may be
experimental.

The software, including the manual, is licensed
under the [European Union Public License 1.2 (or
later)](https://zettelstore.de/home/file?name=LICENSE.txt&ci=trunk).

0.18.0-dev

//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2020-present Detlef Stern
//-----------------------------------------------------------------------------

package ast

import "t73f.de/r/zsc/attrs"

// Definition of Block nodes.

// BlockSlice is a slice of BlockNodes.
type BlockSlice []BlockNode

func (*BlockSlice) blockNode() { /* Just a marker */ }

//-----------------------------------------------------------------------------

package ast

import (
	"unicode/utf8"

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

// Definitions of inline nodes.

// InlineSlice is a list of BlockNodes.
type InlineSlice []InlineNode

package ast

import (
	"net/url"
	"strings"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/zettel/id"
)

// QueryPrefix is the prefix that denotes a query expression.
const QueryPrefix = api.QueryPrefix

// ParseReference parses a string and returns a reference.

//-----------------------------------------------------------------------------

package ast_test

import (
	"testing"

	"t73f.de/r/zsc/attrs"
	"zettelstore.de/z/ast"
)

func BenchmarkWalk(b *testing.B) {
	root := ast.BlockSlice{
		&ast.HeadingNode{
			Inlines: ast.CreateInlineSliceFromWords("A", "Simple", "Heading"),

import (
	"bytes"
	"crypto"
	"crypto/hmac"
	"encoding/base64"

	"t73f.de/r/sx"
	"t73f.de/r/sx/sxreader"
)

var encoding = base64.RawURLEncoding

const digestAlg = crypto.SHA384

func sign(claim sx.Object, secret []byte) ([]byte, error) {

import (
	"errors"
	"hash/fnv"
	"io"
	"time"

	"t73f.de/r/sx"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/sexp"
	"zettelstore.de/z/auth"
	"zettelstore.de/z/auth/policy"
	"zettelstore.de/z/box"
	"zettelstore.de/z/config"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"

	if !ok || subject == "" {
		return nil, ErrNoIdent
	}

	now := time.Now().Round(time.Second)
	sClaim := sx.MakeList(
		sx.Int64(kind),
		sx.MakeString(subject),
		sx.Int64(now.Unix()),
		sx.Int64(now.Add(d).Unix()),
		sx.Int64(ident.Zid),
	)
	return sign(sClaim, a.secret)
}

	vals, err := sexp.ParseList(obj, "isiii")
	if err != nil {
		return ErrMalformedToken
	}
	if auth.TokenKind(vals[0].(sx.Int64)) != k {
		return ErrOtherKind
	}
	ident := vals[1].(sx.String).GetValue()
	if ident == "" {
		return ErrNoIdent
	}
	issued := time.Unix(int64(vals[2].(sx.Int64)), 0)
	expires := time.Unix(int64(vals[3].(sx.Int64)), 0)
	now := time.Now().Round(time.Second)
	if expires.Before(now) {

// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2020-present Detlef Stern
//-----------------------------------------------------------------------------

package policy

import (
	"t73f.de/r/zsc/api"
	"zettelstore.de/z/auth"
	"zettelstore.de/z/zettel/meta"
)

type defaultPolicy struct {
	manager auth.AuthzManager
}

// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2020-present Detlef Stern
//-----------------------------------------------------------------------------

package policy

import (
	"t73f.de/r/zsc/api"
	"zettelstore.de/z/auth"
	"zettelstore.de/z/config"
	"zettelstore.de/z/zettel/meta"
)

type ownerPolicy struct {
	manager    auth.AuthzManager

package policy

import (
	"fmt"
	"testing"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/auth"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

func TestPolicies(t *testing.T) {
	t.Parallel()

import (
	"context"
	"errors"
	"fmt"
	"io"
	"time"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/query"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

// BaseBox is implemented by all Zettel boxes.

// Package compbox provides zettel that have computed content.
package compbox

import (
	"context"
	"net/url"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/box"
	"zettelstore.de/z/box/manager"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/query"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"

	meta    func(id.Zid) *meta.Meta
	content func(*meta.Meta) []byte
}{
	id.MustParse(api.ZidVersion):              {genVersionBuildM, genVersionBuildC},
	id.MustParse(api.ZidHost):                 {genVersionHostM, genVersionHostC},
	id.MustParse(api.ZidOperatingSystem):      {genVersionOSM, genVersionOSC},
	id.MustParse(api.ZidLog):                  {genLogM, genLogC},
	id.MustParse(api.ZidMemory):               {genMemoryM, genMemoryC},
	id.MustParse(api.ZidBoxManager):           {genManagerM, genManagerC},
	id.MustParse(api.ZidMetadataKey):          {genKeysM, genKeysC},
	id.MustParse(api.ZidParser):               {genParserM, genParserC},
	id.MustParse(api.ZidStartupConfiguration): {genConfigZettelM, genConfigZettelC},
}

// Get returns the one program box.

//-----------------------------------------------------------------------------

package compbox

import (
	"bytes"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

func genConfigZettelM(zid id.Zid) *meta.Meta {
	if myConfig == nil {

package compbox

import (
	"bytes"
	"fmt"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

func genKeysM(zid id.Zid) *meta.Meta {
	m := meta.New(zid)

//-----------------------------------------------------------------------------

package compbox

import (
	"bytes"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

func genLogM(zid id.Zid) *meta.Meta {
	m := meta.New(zid)

package compbox

import (
	"bytes"
	"fmt"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

func genManagerM(zid id.Zid) *meta.Meta {
	m := meta.New(zid)

//-----------------------------------------------------------------------------
// Copyright (c) 2024-present Detlef Stern
//
// This file is part of Zettelstore.
//
// Zettelstore 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 compbox

import (
	"bytes"
	"fmt"
	"os"
	"runtime"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

func genMemoryM(zid id.Zid) *meta.Meta {
	if myConfig == nil {
		return nil
	}
	m := meta.New(zid)
	m.Set(api.KeyTitle, "Zettelstore Memory")
	m.Set(api.KeyCreated, kernel.Main.GetConfig(kernel.CoreService, kernel.CoreStarted).(string))
	m.Set(api.KeyVisibility, api.ValueVisibilityExpert)
	return m
}

func genMemoryC(*meta.Meta) []byte {
	pageSize := os.Getpagesize()
	var m runtime.MemStats
	runtime.GC()
	runtime.ReadMemStats(&m)

	var buf bytes.Buffer
	buf.WriteString("|=Name|=Value>\n")
	fmt.Fprintf(&buf, "|Page Size|%d\n", pageSize)
	fmt.Fprintf(&buf, "|Pages|%d\n", m.HeapSys/uint64(pageSize))
	fmt.Fprintf(&buf, "|Heap Objects|%d\n", m.HeapObjects)
	fmt.Fprintf(&buf, "|Heap Sys (KiB)|%d\n", m.HeapSys/1024)
	fmt.Fprintf(&buf, "|Heap Inuse (KiB)|%d\n", m.HeapInuse/1024)
	debug := kernel.Main.GetConfig(kernel.CoreService, kernel.CoreDebug).(bool)
	if debug {
		for i, bysize := range m.BySize {
			fmt.Fprintf(&buf, "|Size %2d: %d|%d - %d → %d\n",
				i, bysize.Size, bysize.Mallocs, bysize.Frees, bysize.Mallocs-bysize.Frees)
		}
	}
	return buf.Bytes()
}

import (
	"bytes"
	"fmt"
	"sort"
	"strings"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

func genParserM(zid id.Zid) *meta.Meta {

// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2020-present Detlef Stern
//-----------------------------------------------------------------------------

package compbox

import (
	"t73f.de/r/zsc/api"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

func getVersionMeta(zid id.Zid, title string) *meta.Meta {
	m := meta.New(zid)

package constbox

import (
	"context"
	_ "embed" // Allow to embed file content
	"net/url"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/box"
	"zettelstore.de/z/box/manager"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/query"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"

			api.KeyTitle:      "Zettelstore Dependencies",
			api.KeyRole:       api.ValueRoleConfiguration,
			api.KeySyntax:     meta.SyntaxZmk,
			api.KeyLang:       api.ValueLangEN,
			api.KeyReadOnly:   api.ValueTrue,
			api.KeyVisibility: api.ValueVisibilityPublic,
			api.KeyCreated:    "20210504135842",
			api.KeyModified:   "20240418095500",
		},
		zettel.NewContent(contentDependencies)},
	id.BaseTemplateZid: {
		constHeader{
			api.KeyTitle:      "Zettelstore Base HTML Template",
			api.KeyRole:       api.ValueRoleConfiguration,
			api.KeySyntax:     meta.SyntaxSxn,

FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.
```

=== Sx, SxWebs, Webs, Zettelstore-Client
These are companion projects, written by the main developer of Zettelstore.
They are published under the same license, [[EUPL v1.2, or later|00000000000004]].

; URL & Source Sx
: [[https://t73f.de/r/sx]]
; URL & Source SxWebs
: [[https://t73f.de/r/sxwebs]]
; URL & Source Webs
: [[https://t73f.de/r/webs]]
; URL & Source Zettelstore-Client
: [[https://t73f.de/r/zsc]]
; License:
: European Union Public License, version 1.2 (EUPL v1.2), or later.

;;;
;;; SPDX-License-Identifier: EUPL-1.2
;;; SPDX-FileCopyrightText: 2023-present Detlef Stern
;;;----------------------------------------------------------------------------

;;; This zettel contains sxn definitions that are independent of specific
;;; subsystems, such as WebUI, API, or other. It just contains generic code to
;;; be used in all places. It asumes that the symbols NIL and T are defined.











;; not macro
(defmacro not (x) `(if ,x NIL T))

;; not= macro, to negate an equivalence
(defmacro not= args `(not (= ,@args)))








;; let* macro
;;
;; (let* (BINDING ...) EXPR ...), where SYMBOL may occur in later bindings.
(defmacro let* (bindings . body)
    (if (null? bindings)
        `(begin ,@body)
        `(let ((,(caar bindings) ,(cadar bindings)))
               (let* ,(cdr bindings) ,@body))))


;; cond macro
;;
;; (cond ((COND EXPR) ...))
(defmacro cond clauses
    (if (null? clauses)
        ()
        (let* ((clause (car clauses))
               (the-cond (car clause)))
              (if (= the-cond T)
                  `(begin ,@(cdr clause))
                  `(if ,the-cond
                       (begin ,@(cdr clause))
                       (cond ,@(cdr clauses)))))))

;; and macro
;;
;; (and EXPR ...)
(defmacro and args
    (cond ((null? args)       T)

;;; SPDX-License-Identifier: EUPL-1.2
;;; SPDX-FileCopyrightText: 2023-present Detlef Stern
;;;----------------------------------------------------------------------------

;; Contains WebUI specific code, but not related to a specific template.

;; wui-list-item returns the argument as a HTML list item.
(defun wui-item (s) `(li ,s))

;; wui-info-meta-table-row takes a pair and translates it into a HTML table row
;; with two columns.
(defun wui-info-meta-table-row (p)
    `(tr (td (@ (class zs-info-meta-key)) ,(car p)) (td (@ (class zs-info-meta-value)) ,(cdr p))))

;; wui-valid-link translates a local link into a HTML link. A link is a pair
;; (valid . url). If valid is not truish, only the invalid url is returned.
(defun wui-valid-link (l)
    (if (car l)
        `(li (a (@ (href ,(cdr l))) ,(cdr l)))
        `(li ,(cdr l))))

;; wui-link takes a link (title . url) and returns a HTML reference.
(defun wui-link (q)
    `(a (@ (href ,(cdr q))) ,(car q)))

;; wui-item-link taks a pair (text . url) and returns a HTML link inside
;; a list item.
(defun wui-item-link (q) `(li ,(wui-link q)))

;; wui-tdata-link taks a pair (text . url) and returns a HTML link inside
;; a table data item.
(defun wui-tdata-link (q) `(td ,(wui-link q)))

;; wui-item-popup-link is like 'wui-item-link, but the HTML link will open
;; a new tab / window.
(defun wui-item-popup-link (e)
    `(li (a (@ (href ,e) (target "_blank") (rel "noopener noreferrer")) ,e)))

;; wui-option-value returns a value for an HTML option element.
(defun wui-option-value (v) `(option (@ (value ,v))))

;; wui-datalist returns a HTML datalist with the given HTML identifier and a
;; list of values.
(defun wui-datalist (id lst)
    (if lst
        `((datalist (@ (id ,id)) ,@(map wui-option-value lst)))))

;; wui-pair-desc-item takes a pair '(term . text) and returns a list with
;; a HTML description term and a HTML description data. 
(defun wui-pair-desc-item (p) `((dt ,(car p)) (dd ,(cdr p))))

;; wui-meta-desc returns a HTML description list made from the list of pairs
;; given.
(defun wui-meta-desc (l)
    `(dl ,@(apply append (map wui-pair-desc-item l))))

;; wui-enc-matrix returns the HTML table of all encodings and parts.
(defun wui-enc-matrix (matrix)
    `(table
      ,@(map
         (lambda (row) `(tr (th ,(car row)) ,@(map wui-tdata-link (cdr row))))
         matrix)))

;; CSS-ROLE-map is a mapping (pair list, assoc list) of role names to zettel
;; identifier. It is used in the base template to update the metadata of the

	"context"
	"fmt"
	"io"
	"os"
	"path/filepath"
	"time"

	"t73f.de/r/zsc/input"
	"zettelstore.de/z/box/filebox"
	"zettelstore.de/z/box/notify"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"

		entry.Zid,
		entry.ContentExt,
		entry.MetaName != "",
		entry.UselessFiles,
	)
}

// fileMode to create a new file: user, group, and all are allowed to read and write.
//
// If you want to forbid others or the group to read or to write, you must set
// umask(1) accordingly.
const fileMode os.FileMode = 0666 //

func openFileWrite(path string) (*os.File, error) {
	return os.OpenFile(path, os.O_WRONLY|os.O_CREATE|os.O_TRUNC, fileMode)
}

func writeFileZid(w io.Writer, zid id.Zid) error {
	_, err := io.WriteString(w, "id: ")
	if err == nil {
		_, err = w.Write(zid.Bytes())
		if err == nil {

import (
	"errors"
	"net/url"
	"path/filepath"
	"strings"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/box"
	"zettelstore.de/z/box/manager"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

import (
	"archive/zip"
	"context"
	"fmt"
	"io"
	"strings"

	"t73f.de/r/zsc/input"
	"zettelstore.de/z/box"
	"zettelstore.de/z/box/notify"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/query"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"

package manager

import (
	"context"
	"strconv"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/box"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

// Enrich computes additional properties and updates the given metadata.
func (mgr *Manager) Enrich(ctx context.Context, m *meta.Meta, boxNumber int) {

	"context"
	"fmt"
	"io"
	"sort"
	"strings"
	"sync"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/maps"
	"zettelstore.de/z/box"
	"zettelstore.de/z/box/manager/store"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

type zettelData struct {

//-----------------------------------------------------------------------------

package notify

import (
	"path/filepath"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

const (

import (
	"context"
	"flag"
	"fmt"
	"io"
	"os"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

import (
	"flag"
	"fmt"
	"os"

	"golang.org/x/term"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/auth/cred"
	"zettelstore.de/z/zettel/id"
)

// ---------- Subcommand: password -------------------------------------------

func cmdPassword(fs *flag.FlagSet) (int, error) {

//-----------------------------------------------------------------------------

package cmd

import (
	"flag"

	"t73f.de/r/zsc/maps"
	"zettelstore.de/z/logger"
)

// Command stores information about commands / sub-commands.
type Command struct {
	Name       string              // command name as it appears on the command line
	Func       CommandFunc         // function that executes a command

	"net/url"
	"os"
	"runtime/debug"
	"strconv"
	"strings"
	"time"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/auth"
	"zettelstore.de/z/auth/impl"
	"zettelstore.de/z/box"
	"zettelstore.de/z/box/compbox"
	"zettelstore.de/z/box/manager"
	"zettelstore.de/z/config"
	"zettelstore.de/z/kernel"

id: 00001005090000
title: List of predefined zettel
role: manual
tags: #manual #reference #zettelstore
syntax: zmk
created: 20210126175322
modified: 20240318115839

The following table lists all predefined zettel with their purpose.

|= Identifier :|= Title | Purpose
| [[00000000000001]] | Zettelstore Version | Contains the version string of the running Zettelstore
| [[00000000000002]] | Zettelstore Host | Contains the name of the computer running the Zettelstore
| [[00000000000003]] | Zettelstore Operating System | Contains the operating system and CPU architecture of the computer running the Zettelstore
| [[00000000000004]] | Zettelstore License | Lists the license of Zettelstore
| [[00000000000005]] | Zettelstore Contributors | Lists all contributors of Zettelstore
| [[00000000000006]] | Zettelstore Dependencies | Lists all licensed content
| [[00000000000007]] | Zettelstore Log | Lists the last 8192 log messages
| [[00000000000008]] | Zettelstore Memory | Some statistics about main memory usage
| [[00000000000020]] | Zettelstore Box Manager | Contains some statistics about zettel boxes and the the index process
| [[00000000000090]] | Zettelstore Supported Metadata Keys | Contains all supported metadata keys, their [[types|00001006030000]], and more
| [[00000000000092]] | Zettelstore Supported Parser | Lists all supported values for metadata [[syntax|00001006020000#syntax]] that are recognized by Zettelstore
| [[00000000000096]] | Zettelstore Startup Configuration | Contains the effective values of the [[startup configuration|00001004010000]]
| [[00000000000100]] | Zettelstore Runtime Configuration | Allows to [[configure Zettelstore at runtime|00001004020000]]
| [[00000000010100]] | Zettelstore Base HTML Template | Contains the general layout of the HTML view
| [[00000000010200]] | Zettelstore Login Form HTML Template | Layout of the login form, when authentication is [[enabled|00001010040100]]

| [[00000000090001]] | New Zettel | Template for a new zettel with role ""[[zettel|00001006020100#zettel]]""
| [[00000000090002]] | New User | Template for a new [[user zettel|00001010040200]]
| [[00000000090003]] | New Tag | Template for a new [[tag zettel|00001006020100#tag]]
| [[00000000090004]] | New Role | Template for a new [[role zettel|00001006020100#role]]
| [[00010000000000]] | Home | Default home zettel, contains some welcome information

If a zettel is not linked, it is not accessible for the current user.
In most cases, you must at least enable [[''expert-mode''|00001004020000#expert-mode]].

**Important:** All identifier may change until a stable version of the software is released.

id: 00001008000000
title: Other Markup Languages
role: manual
tags: #manual #zettelstore
syntax: zmk
created: 20210126175300
modified: 20240413160242

[[Zettelmarkup|00001007000000]] is not the only markup language you can use to define your content.
Zettelstore is quite agnostic with respect to markup languages.
Of course, Zettelmarkup plays an important role.
However, with the exception of zettel titles, you can use any (markup) language that is supported:

* CSS

: Only the metadata of a zettel is ""parsed"".
  Useful for displaying the full metadata.
  The [[runtime configuration zettel|00000000000100]] uses this syntax.
  The zettel content is ignored.
; [!svg|''svg'']
: [[Scalable Vector Graphics|https://www.w3.org/TR/SVG2/]].
; [!sxn|''sxn'']
: S-Expressions, as implemented by [[Sx|https://t73f.de/r/sx]].
  Often used to specify templates when rendering a zettel as HTML for the [[web user interface|00001014000000]] (with the help of sxhtml]).
; [!text|''text''], [!plain|''plain''], [!txt|''txt'']
: Plain text that must not be interpreted further.
; [!zmk|''zmk'']
: [[Zettelmarkup|00001007000000]].

The actual values are also listed in a zettel named [[Zettelstore Supported Parser|00000000000092]].

If you specify something else, your content will be interpreted as plain text.

id: 00001012930500
title: Syntax of Symbolic Expressions
role: manual
tags: #manual #reference #zettelstore
syntax: zmk
created: 20230403151127
modified: 20240413160345

=== Syntax of lists
A list always starts with the left parenthesis (""''(''"", U+0028) and ends with a right parenthesis (""'')''"", U+0029).
A list may contain a possibly empty sequence of elements, i.e. lists and / or atoms.

Internally, lists are composed of __cells__.
A cell allows to store two values.

To allow a string to contain a backslash, it also must be prefixed by one backslash.
Unicode characters with a code less than U+FF are encoded by by the sequence ""''\\xNM''"", where ''NM'' is the hex encoding of the character.
Unicode characters with a code less than U+FFFF are encoded by by the sequence ""''\\uNMOP''"", where ''NMOP'' is the hex encoding of the character.
Unicode characters with a code less than U+FFFFFF are encoded by by the sequence ""''\\UNMOPQR''"", where ''NMOPQR'' is the hex encoding of the character.
In addition, the sequence ""''\\t''"" encodes a horizontal tab (U+0009), the sequence ""''\\n''"" encodes a line feed (U+000A).

=== See also
* Currently, Zettelstore uses [[Sx|https://t73f.de/r/sx]] (""Symbolic eXpression framework"") to implement symbolic expressions.
  The project page might contain additional information about the full syntax.

  Zettelstore only uses lists, numbers, string, and symbols to represent zettel.

package encoder

import (
	"errors"
	"fmt"
	"io"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/zettel/meta"
)

// Encoder is an interface that allows to encode different parts of a zettel.
type Encoder interface {
	WriteZettel(io.Writer, *ast.ZettelNode, EvalMetaFunc) (int, error)

//-----------------------------------------------------------------------------

package encoder_test

import (
	"testing"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/config"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"

	_ "zettelstore.de/z/parser/blob" // Allow to use BLOB parser.
)

package encoder_test

import (
	"fmt"
	"strings"
	"testing"

	"t73f.de/r/sx/sxreader"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/config"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/meta"

	_ "zettelstore.de/z/encoder/htmlenc"  // Allow to use HTML encoder.

// Package htmlenc encodes the abstract syntax tree into HTML5 via zettelstore-client.
package htmlenc

import (
	"io"
	"strings"

	"t73f.de/r/sx"
	"t73f.de/r/sxwebs/sxhtml"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/shtml"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/encoder/szenc"
	"zettelstore.de/z/encoder/textenc"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/meta"
)

	if err != nil {
		return 0, err
	}
	hen := he.th.Endnotes(&env)

	var head sx.ListBuilder
	head.Add(shtml.SymHead)
	head.Add(sx.Nil().Cons(sx.Nil().Cons(sx.Cons(sx.MakeSymbol("charset"), sx.MakeString("utf-8"))).Cons(sxhtml.SymAttr)).Cons(shtml.SymMeta))
	head.ExtendBang(hm)
	var sb strings.Builder
	if hasTitle {
		he.textEnc.WriteInlines(&sb, &isTitle)
	} else {
		sb.Write(zn.Meta.Zid.Bytes())
	}
	head.Add(sx.MakeList(shtml.SymAttrTitle, sx.MakeString(sb.String())))

	var body sx.ListBuilder
	body.Add(shtml.SymBody)
	if hasTitle {
		body.Add(htitle.Cons(shtml.SymH1))
	}
	body.ExtendBang(hast)
	if hen != nil {
		body.Add(sx.Cons(shtml.SymHR, nil))
		body.Add(hen)
	}

	doc := sx.MakeList(
		sxhtml.SymDoctype,
		sx.MakeList(shtml.SymHtml, head.List(), body.List()),
	)

	gen := sxhtml.NewGenerator().SetNewline()
	return gen.WriteHTML(w, doc)
}

// WriteMeta encodes meta data as HTML5.
func (he *Encoder) WriteMeta(w io.Writer, m *meta.Meta, evalMeta encoder.EvalMetaFunc) (int, error) {
	env := shtml.MakeEnvironment(he.lang)
	hm, err := he.th.Evaluate(he.tx.GetMeta(m, evalMeta), &env)
	if err != nil {
		return 0, err
	}
	gen := sxhtml.NewGenerator().SetNewline()
	return gen.WriteListHTML(w, hm)
}

func (he *Encoder) WriteContent(w io.Writer, zn *ast.ZettelNode) (int, error) {
	return he.WriteBlocks(w, &zn.Ast)
}

// Package mdenc encodes the abstract syntax tree back into Markdown.
package mdenc

import (
	"io"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/zettel/meta"
)

func init() {
	encoder.Register(api.EncoderMD, func(*encoder.CreateParameter) encoder.Encoder { return Create() })

// Package shtmlenc encodes the abstract syntax tree into a s-expr which represents HTML.
package shtmlenc

import (
	"io"

	"t73f.de/r/sx"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/shtml"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/encoder/szenc"
	"zettelstore.de/z/zettel/meta"
)

func init() {

// Package szenc encodes the abstract syntax tree into a s-expr for zettel.
package szenc

import (
	"io"

	"t73f.de/r/sx"
	"t73f.de/r/zsc/api"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/zettel/meta"
)

func init() {
	encoder.Register(api.EncoderSz, func(*encoder.CreateParameter) encoder.Encoder { return Create() })

package szenc

import (
	"encoding/base64"
	"fmt"
	"strings"

	"t73f.de/r/sx"
	"t73f.de/r/zsc/attrs"
	"t73f.de/r/zsc/sz"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/zettel/meta"
)

// NewTransformer returns a new transformer to create s-expressions from AST nodes.
func NewTransformer() *Transformer {

		return t.getInlineList(*n).Cons(sz.SymInline)
	case *ast.ParaNode:
		return t.getInlineList(n.Inlines).Cons(sz.SymPara)
	case *ast.VerbatimNode:
		return sx.MakeList(
			mapGetS(mapVerbatimKindS, n.Kind),
			getAttributes(n.Attrs),
			sx.MakeString(string(n.Content)),
		)
	case *ast.RegionNode:
		return t.getRegion(n)
	case *ast.HeadingNode:
		return t.getInlineList(n.Inlines).
			Cons(sx.MakeString(n.Fragment)).
			Cons(sx.MakeString(n.Slug)).
			Cons(getAttributes(n.Attrs)).
			Cons(sx.Int64(int64(n.Level))).
			Cons(sz.SymHeading)
	case *ast.HRuleNode:
		return sx.MakeList(sz.SymThematic, getAttributes(n.Attrs))
	case *ast.NestedListNode:
		return t.getNestedList(n)
	case *ast.DescriptionListNode:
		return t.getDescriptionList(n)
	case *ast.TableNode:
		return t.getTable(n)
	case *ast.TranscludeNode:
		return sx.MakeList(sz.SymTransclude, getAttributes(n.Attrs), getReference(n.Ref))
	case *ast.BLOBNode:
		return t.getBLOB(n)
	case *ast.TextNode:
		return sx.MakeList(sz.SymText, sx.MakeString(n.Text))
	case *ast.SpaceNode:
		if t.inVerse {
			return sx.MakeList(sz.SymSpace, sx.MakeString(n.Lexeme))
		}
		return sx.MakeList(sz.SymSpace)
	case *ast.BreakNode:
		if n.Hard {
			return sx.MakeList(sz.SymHard)
		}
		return sx.MakeList(sz.SymSoft)
	case *ast.LinkNode:
		return t.getLink(n)
	case *ast.EmbedRefNode:
		return t.getInlineList(n.Inlines).
			Cons(sx.MakeString(n.Syntax)).
			Cons(getReference(n.Ref)).
			Cons(getAttributes(n.Attrs)).
			Cons(sz.SymEmbed)
	case *ast.EmbedBLOBNode:
		return t.getEmbedBLOB(n)
	case *ast.CiteNode:
		return t.getInlineList(n.Inlines).
			Cons(sx.MakeString(n.Key)).
			Cons(getAttributes(n.Attrs)).
			Cons(sz.SymCite)
	case *ast.FootnoteNode:
		// (ENDNODE attrs InlineElement ...)
		return t.getInlineList(n.Inlines).Cons(getAttributes(n.Attrs)).Cons(sz.SymEndnote)
	case *ast.MarkNode:
		return t.getInlineList(n.Inlines).
			Cons(sx.MakeString(n.Fragment)).
			Cons(sx.MakeString(n.Slug)).
			Cons(sx.MakeString(n.Mark)).
			Cons(sz.SymMark)
	case *ast.FormatNode:
		return t.getInlineList(n.Inlines).
			Cons(getAttributes(n.Attrs)).
			Cons(mapGetS(mapFormatKindS, n.Kind))
	case *ast.LiteralNode:
		return sx.MakeList(
			mapGetS(mapLiteralKindS, n.Kind),
			getAttributes(n.Attrs),
			sx.MakeString(string(n.Content)),
		)
	}
	return sx.MakeList(sz.SymUnknown, sx.MakeString(fmt.Sprintf("%T %v", node, node)))
}

var mapVerbatimKindS = map[ast.VerbatimKind]*sx.Symbol{
	ast.VerbatimZettel:  sz.SymVerbatimZettel,
	ast.VerbatimProg:    sz.SymVerbatimProg,
	ast.VerbatimEval:    sz.SymVerbatimEval,
	ast.VerbatimMath:    sz.SymVerbatimMath,

func (t *Transformer) getCell(cell *ast.TableCell) *sx.Pair {
	return t.getInlineList(cell.Inlines).Cons(mapGetS(alignmentSymbolS, cell.Align))
}

func (t *Transformer) getBLOB(bn *ast.BLOBNode) *sx.Pair {
	var lastObj sx.Object
	if bn.Syntax == meta.SyntaxSVG {
		lastObj = sx.MakeString(string(bn.Blob))
	} else {
		lastObj = getBase64String(bn.Blob)
	}
	return sx.MakeList(
		sz.SymBLOB,
		t.getInlineList(bn.Description),
		sx.MakeString(bn.Syntax),
		lastObj,
	)
}

var mapRefStateLink = map[ast.RefState]*sx.Symbol{
	ast.RefStateInvalid:  sz.SymLinkInvalid,
	ast.RefStateZettel:   sz.SymLinkZettel,
	ast.RefStateSelf:     sz.SymLinkSelf,
	ast.RefStateFound:    sz.SymLinkFound,
	ast.RefStateBroken:   sz.SymLinkBroken,
	ast.RefStateHosted:   sz.SymLinkHosted,
	ast.RefStateBased:    sz.SymLinkBased,
	ast.RefStateQuery:    sz.SymLinkQuery,
	ast.RefStateExternal: sz.SymLinkExternal,
}

func (t *Transformer) getLink(ln *ast.LinkNode) *sx.Pair {
	return t.getInlineList(ln.Inlines).
		Cons(sx.MakeString(ln.Ref.Value)).
		Cons(getAttributes(ln.Attrs)).
		Cons(mapGetS(mapRefStateLink, ln.Ref.State))
}

func (t *Transformer) getEmbedBLOB(en *ast.EmbedBLOBNode) *sx.Pair {
	tail := t.getInlineList(en.Inlines)
	if en.Syntax == meta.SyntaxSVG {
		tail = tail.Cons(sx.MakeString(string(en.Blob)))
	} else {
		tail = tail.Cons(getBase64String(en.Blob))
	}
	return tail.Cons(sx.MakeString(en.Syntax)).Cons(getAttributes(en.Attrs)).Cons(sz.SymEmbedBLOB)
}

func (t *Transformer) getBlockList(bs *ast.BlockSlice) *sx.Pair {
	objs := make(sx.Vector, len(*bs))
	for i, n := range *bs {
		objs[i] = t.GetSz(n)
	}

func getAttributes(a attrs.Attributes) sx.Object {
	if a.IsEmpty() {
		return sx.Nil()
	}
	keys := a.Keys()
	objs := make(sx.Vector, 0, len(keys))
	for _, k := range keys {
		objs = append(objs, sx.Cons(sx.MakeString(k), sx.MakeString(a[k])))
	}
	return sx.MakeList(objs...)
}

var mapRefStateS = map[ast.RefState]*sx.Symbol{
	ast.RefStateInvalid:  sz.SymRefStateInvalid,
	ast.RefStateZettel:   sz.SymRefStateZettel,
	ast.RefStateSelf:     sz.SymRefStateSelf,
	ast.RefStateFound:    sz.SymRefStateFound,
	ast.RefStateBroken:   sz.SymRefStateBroken,
	ast.RefStateHosted:   sz.SymRefStateHosted,
	ast.RefStateBased:    sz.SymRefStateBased,
	ast.RefStateQuery:    sz.SymRefStateQuery,
	ast.RefStateExternal: sz.SymRefStateExternal,
}

func getReference(ref *ast.Reference) *sx.Pair {
	return sx.MakeList(mapGetS(mapRefStateS, ref.State), sx.MakeString(ref.Value))
}

var mapMetaTypeS = map[*meta.DescriptionType]*sx.Symbol{
	meta.TypeCredential:   sz.SymTypeCredential,
	meta.TypeEmpty:        sz.SymTypeEmpty,
	meta.TypeID:           sz.SymTypeID,
	meta.TypeIDSet:        sz.SymTypeIDSet,

		ty := m.Type(key)
		symType := mapGetS(mapMetaTypeS, ty)
		var obj sx.Object
		if ty.IsSet {
			setList := meta.ListFromValue(p.Value)
			setObjs := make(sx.Vector, len(setList))
			for i, val := range setList {
				setObjs[i] = sx.MakeString(val)
			}
			obj = sx.MakeList(setObjs...)
		} else if ty == meta.TypeZettelmarkup {
			is := evalMeta(p.Value)
			obj = t.getInlineList(is)
		} else {
			obj = sx.MakeString(p.Value)
		}
		objs = append(objs, sx.Nil().Cons(obj).Cons(sx.MakeSymbol(key)).Cons(symType))
	}
	return sx.MakeList(objs...).Cons(sz.SymMeta)
}

func mapGetS[T comparable](m map[T]*sx.Symbol, k T) *sx.Symbol {

	var sb strings.Builder
	encoder := base64.NewEncoder(base64.StdEncoding, &sb)
	_, err := encoder.Write(data)
	if err == nil {
		err = encoder.Close()
	}
	if err == nil {
		return sx.MakeString(sb.String())
	}
	return sx.MakeString("")
}

// Package textenc encodes the abstract syntax tree into its text.
package textenc

import (
	"io"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/zettel/meta"
)

func init() {
	encoder.Register(api.EncoderText, func(*encoder.CreateParameter) encoder.Encoder { return Create() })

package zmkenc

import (
	"fmt"
	"io"
	"strings"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/attrs"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/encoder/textenc"
	"zettelstore.de/z/strfun"
	"zettelstore.de/z/zettel/meta"
)

// Package atom provides an Atom encoding.
package atom

import (
	"bytes"
	"time"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/config"
	"zettelstore.de/z/encoding"
	"zettelstore.de/z/encoding/xml"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/query"
	"zettelstore.de/z/strfun"
	"zettelstore.de/z/zettel/id"

// Package encoding provides helper functions for encodings.
package encoding

import (
	"time"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

// LastUpdated returns the formated time of the zettel which was updated at the latest time.
func LastUpdated(ml []*meta.Meta, timeFormat string) string {

package rss

import (
	"bytes"
	"context"
	"time"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/config"
	"zettelstore.de/z/encoding"
	"zettelstore.de/z/encoding/xml"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/query"
	"zettelstore.de/z/strfun"
	"zettelstore.de/z/zettel/id"

	"context"
	"errors"
	"fmt"
	"path"
	"strconv"
	"strings"

	"t73f.de/r/sx/sxbuiltins"
	"t73f.de/r/sx/sxreader"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/attrs"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/box"
	"zettelstore.de/z/config"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/parser/cleaner"
	"zettelstore.de/z/parser/draw"
	"zettelstore.de/z/query"

	"bytes"
	"context"
	"math"
	"sort"
	"strconv"
	"strings"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/attrs"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/config"
	"zettelstore.de/z/encoding/atom"
	"zettelstore.de/z/encoding/rss"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/query"
	"zettelstore.de/z/zettel/meta"

module zettelstore.de/z

go 1.22

require (
	github.com/fsnotify/fsnotify v1.7.0
	github.com/yuin/goldmark v1.7.1
	golang.org/x/crypto v0.23.0
	golang.org/x/term v0.20.0
	golang.org/x/text v0.15.0
	t73f.de/r/sx v0.0.0-20240418072254-b6eff7d787f9
	t73f.de/r/sxwebs v0.0.0-20240506145202-e8d9730ec7be
	t73f.de/r/zsc v0.0.0-20240422145115-3bbfcfd9394c
)

require (
	golang.org/x/sys v0.20.0 // indirect
	t73f.de/r/webs v0.0.0-20240506131458-2ca382cb6824 // indirect
)

github.com/fsnotify/fsnotify v1.7.0 h1:8JEhPFa5W2WU7YfeZzPNqzMP6Lwt7L2715Ggo0nosvA=
github.com/fsnotify/fsnotify v1.7.0/go.mod h1:40Bi/Hjc2AVfZrqy+aj+yEI+/bRxZnMJyTJwOpGvigM=
github.com/yuin/goldmark v1.7.1 h1:3bajkSilaCbjdKVsKdZjZCLBNPL9pYzrCakKaf4U49U=
github.com/yuin/goldmark v1.7.1/go.mod h1:uzxRWxtg69N339t3louHJ7+O03ezfj6PlliRlaOzY1E=
golang.org/x/crypto v0.23.0 h1:dIJU/v2J8Mdglj/8rJ6UUOM3Zc9zLZxVZwwxMooUSAI=
golang.org/x/crypto v0.23.0/go.mod h1:CKFgDieR+mRhux2Lsu27y0fO304Db0wZe70UKqHu0v8=
golang.org/x/sys v0.20.0 h1:Od9JTbYCk261bKm4M/mw7AklTlFYIa0bIp9BgSm1S8Y=
golang.org/x/sys v0.20.0/go.mod h1:/VUhepiaJMQUp4+oa/7Zr1D23ma6VTLIYjOOTFZPUcA=
golang.org/x/term v0.20.0 h1:VnkxpohqXaOBYJtBmEppKUG6mXpi+4O6purfc2+sMhw=
golang.org/x/term v0.20.0/go.mod h1:8UkIAJTvZgivsXaD6/pH6U9ecQzZ45awqEOzuCvwpFY=
golang.org/x/text v0.15.0 h1:h1V/4gjBv8v9cjcR6+AR5+/cIYK5N/WAgiv4xlsEtAk=
golang.org/x/text v0.15.0/go.mod h1:18ZOQIKpY8NJVqYksKHtTdi31H5itFRjB5/qKTNYzSU=
t73f.de/r/sx v0.0.0-20240418072254-b6eff7d787f9 h1:lVPkYN8+J9f6JA9SmoF6icvpLxz4u3h1MCTuDYJYwdU=
t73f.de/r/sx v0.0.0-20240418072254-b6eff7d787f9/go.mod h1:G9pD1j2R6y9ZkPBb81mSnmwaAvTOg7r6jKp/OF7WeFA=
t73f.de/r/sxwebs v0.0.0-20240506145202-e8d9730ec7be h1:DlX70vUz/hCMQxr1xVU339h2eUIEqdG2duS0QBqkXFw=
t73f.de/r/sxwebs v0.0.0-20240506145202-e8d9730ec7be/go.mod h1:PtIkpRfTTiQITciKaWcTiAwy9FJ63WSQKciTp/dJbOA=
t73f.de/r/webs v0.0.0-20240506131458-2ca382cb6824 h1:G/5vTUMZp/z6Gm88SUSIthXUIQi90oqI9ZlOBC4W074=
t73f.de/r/webs v0.0.0-20240506131458-2ca382cb6824/go.mod h1:UGAAtul0TK5ACeZ6zTS3SX6GqwMFXxlUpHiV8oqNq5w=
t73f.de/r/zsc v0.0.0-20240422145115-3bbfcfd9394c h1:TOvMeqVXG5s1Rj2a2q3r1+K8LlS9fHruMon0n7Aw5qM=
t73f.de/r/zsc v0.0.0-20240422145115-3bbfcfd9394c/go.mod h1:YdsjqbI1th0bJoMclgbNycJUVr8ovAV02ZgA91uOhkU=

	"context"
	"errors"
	"fmt"
	"strconv"
	"strings"
	"sync"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/box"
	"zettelstore.de/z/config"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/web/server"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"

	"io"
	"os"
	"runtime/metrics"
	"sort"
	"strconv"
	"strings"

	"t73f.de/r/zsc/maps"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/strfun"
)

type cmdSession struct {
	w        io.Writer

	"errors"
	"fmt"
	"sort"
	"strconv"
	"strings"
	"sync"

	"t73f.de/r/zsc/maps"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/zettel/id"
)

type parseFunc func(string) (any, error)
type configDescription struct {

	"fmt"
	"net"
	"os"
	"runtime"
	"sync"
	"time"

	"t73f.de/r/zsc/maps"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/strfun"
	"zettelstore.de/z/zettel/id"
)

type coreService struct {

import (
	"context"
	"net/http"
	"strconv"
	"sync"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/zettel/id"
)

// Message presents a message to log.
type Message struct {
	logger *Logger
	level  Level

// SPDX-FileCopyrightText: 2020-present Detlef Stern
//-----------------------------------------------------------------------------

// Package blob provides a parser of binary data.
package blob

import (
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/meta"
)

func init() {
	parser.Register(&parser.Info{

// It is not a parser registered by the general parser framework (directed by
// metadata "syntax" of a zettel). It will be used when a zettel is evaluated.
package draw

import (
	"strconv"

	"t73f.de/r/zsc/attrs"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/meta"
)

func init() {
	parser.Register(&parser.Info{

//-----------------------------------------------------------------------------

package draw_test

import (
	"testing"

	"t73f.de/r/zsc/input"
	"zettelstore.de/z/config"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/meta"
)

func FuzzParseBlocks(f *testing.F) {
	f.Fuzz(func(t *testing.T, src []byte) {

	"strconv"
	"strings"

	gm "github.com/yuin/goldmark"
	gmAst "github.com/yuin/goldmark/ast"
	gmText "github.com/yuin/goldmark/text"

	"t73f.de/r/zsc/attrs"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/encoder/textenc"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/meta"
)

func init() {

// SPDX-FileCopyrightText: 2020-present Detlef Stern
//-----------------------------------------------------------------------------

// Package none provides a none-parser, e.g. for zettel with just metadata.
package none

import (
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/meta"
)

func init() {
	parser.Register(&parser.Info{

package parser

import (
	"context"
	"fmt"
	"strings"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/config"
	"zettelstore.de/z/parser/cleaner"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/meta"
)

// Package plain provides a parser for plain text data.
package plain

import (
	"bytes"
	"strings"

	"t73f.de/r/sx/sxreader"
	"t73f.de/r/zsc/attrs"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/meta"
)

func init() {
	parser.Register(&parser.Info{

//-----------------------------------------------------------------------------

package zettelmark

import (
	"fmt"

	"t73f.de/r/zsc/input"
	"zettelstore.de/z/ast"
)

// parseBlockSlice parses a sequence of blocks.
func (cp *zmkP) parseBlockSlice() ast.BlockSlice {
	inp := cp.inp
	var lastPara *ast.ParaNode

package zettelmark

import (
	"bytes"
	"fmt"
	"strings"

	"t73f.de/r/zsc/attrs"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/zettel/meta"
)

// parseInlineSlice parses a sequence of Inlines until EOS.
func (cp *zmkP) parseInlineSlice() (ins ast.InlineSlice) {
	inp := cp.inp

// Package zettelmark provides a parser for zettelmarkup.
package zettelmark

import (
	"strings"
	"unicode"

	"t73f.de/r/zsc/attrs"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/meta"
)

func init() {
	parser.Register(&parser.Info{

//-----------------------------------------------------------------------------

package zettelmark_test

import (
	"testing"

	"t73f.de/r/zsc/input"
	"zettelstore.de/z/config"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/meta"
)

func FuzzParseBlocks(f *testing.F) {
	f.Fuzz(func(t *testing.T, src []byte) {

package zettelmark_test

import (
	"fmt"
	"strings"
	"testing"

	"t73f.de/r/zsc/attrs"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/config"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/meta"
)

type TestCase struct{ source, want string }

package query

import (
	"container/heap"
	"context"
	"math"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

// ContextSpec contains all specification values for calculating a context.
type ContextSpec struct {
	Direction ContextDirection

//-----------------------------------------------------------------------------

package query

import (
	"strconv"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

// Parse the query specification and return a Query object.
func Parse(spec string) (q *Query) { return q.Parse(spec) }

package query

import (
	"io"
	"strconv"
	"strings"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/maps"
	"zettelstore.de/z/zettel/id"
)

var op2string = map[compareOp]string{
	cmpExist:     api.ExistOperator,
	cmpNotExist:  api.ExistNotOperator,
	cmpEqual:     api.SearchOperatorEqual,

package query_test

import (
	"context"
	"testing"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/query"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

func TestMatchZidNegate(t *testing.T) {
	q := query.Parse(api.KeyID + api.SearchOperatorHasNot + string(api.ZidVersion) + " " + api.KeyID + api.SearchOperatorHasNot + string(api.ZidLicense))

//-----------------------------------------------------------------------------

package query

import (
	"strconv"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/zettel/meta"
)

type sortFunc func(i, j int) bool

func createSortFunc(order []sortOrder, ml []*meta.Meta) sortFunc {
	hasID := false

//
// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2023-present Detlef Stern
//-----------------------------------------------------------------------------

package query

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

// IdentSpec contains all specification values to calculate the ident directive.
type IdentSpec struct{}

func (spec *IdentSpec) Print(pe *PrintEnv) {
	pe.printSpace()
	pe.writeString(api.IdentDirective)

// SPDX-License-Identifier: EUPL-1.2
// SPDX-FileCopyrightText: 2023-present Detlef Stern
//-----------------------------------------------------------------------------

package query

import (
	"t73f.de/r/zsc/api"
	"zettelstore.de/z/strfun"
	"zettelstore.de/z/zettel/meta"
)

// UnlinkedSpec contains all specification values to calculate unlinked references.
type UnlinkedSpec struct {
	words []string

	"io"
	"net/http"
	"net/url"
	"slices"
	"strconv"
	"testing"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/client"
	"zettelstore.de/z/kernel"
)

func nextZid(zid api.ZettelID) api.ZettelID {
	numVal, err := strconv.ParseUint(string(zid), 10, 64)
	if err != nil {
		panic(err)

		}

	}
}

func TestListZettel(t *testing.T) {
	const (
		ownerZettel      = 56
		configRoleZettel = 34
		writerZettel     = ownerZettel - 25
		readerZettel     = ownerZettel - 25
		creatorZettel    = 10
		publicZettel     = 5
	)

	testdata := []struct {
		user string
		exp  int

package client_test

import (
	"context"
	"strings"
	"testing"

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

// ---------------------------------------------------------------------------
// Tests that change the Zettelstore must nor run parallel to other tests.

func TestCreateGetRenameDeleteZettel(t *testing.T) {
	// Is not to be allowed to run in parallel with other tests.

package client_test

import (
	"context"
	"strings"
	"testing"

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

const (
	abcZid   = api.ZettelID("20211020121000")
	abc10Zid = api.ZettelID("20211020121100")
)

	"bytes"
	"encoding/json"
	"fmt"
	"os"
	"strings"
	"testing"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/config"
	"zettelstore.de/z/encoder"
	_ "zettelstore.de/z/encoder/htmlenc"
	_ "zettelstore.de/z/encoder/mdenc"
	_ "zettelstore.de/z/encoder/shtmlenc"
	_ "zettelstore.de/z/encoder/szenc"

import (
	"bufio"
	"io"
	"os"
	"path/filepath"
	"testing"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	_ "zettelstore.de/z/cmd"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/zettel/meta"
)

// Test all parser / encoder with a list of "naughty strings", i.e. unusual strings

	"io"
	"net/url"
	"os"
	"path/filepath"
	"strings"
	"testing"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/box"
	"zettelstore.de/z/box/manager"
	"zettelstore.de/z/config"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/parser"

	"io"
	"io/fs"
	"os"
	"path/filepath"
	"strings"
	"time"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/strfun"
	"zettelstore.de/z/tools"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

func readVersionFile() (string, error) {

	"math/rand/v2"
	"net/url"
	"os"
	"regexp"
	"sort"
	"strings"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/client"
	"zettelstore.de/z/tools"
)

func main() {
	flag.BoolVar(&tools.Verbose, "v", false, "Verbose output")
	flag.Parse()

	"os/exec"
	"strings"

	"zettelstore.de/z/strfun"
)

var EnvDirectProxy = []string{"GOPROXY=direct"}
var EnvGoVCS = []string{"GOVCS=zettelstore.de:fossil,t73f.de:fossil"}
var Verbose bool

func ExecuteCommand(env []string, name string, arg ...string) (string, error) {
	LogCommand("EXEC", env, name, arg)
	var out strings.Builder
	cmd := PrepareCommand(env, name, arg, nil, &out, os.Stderr)
	err := cmd.Run()

import (
	"context"
	"math/rand/v2"
	"net/http"
	"time"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/auth"
	"zettelstore.de/z/auth/cred"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

package usecase

import (
	"context"
	"time"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/config"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

//-----------------------------------------------------------------------------

package usecase

import (
	"context"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/query"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

// TagZettel is the usecase of retrieving a "tag zettel", i.e. a zettel that

//-----------------------------------------------------------------------------

package usecase

import (
	"context"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/auth"
	"zettelstore.de/z/box"
	"zettelstore.de/z/query"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

//-----------------------------------------------------------------------------

package usecase

import (
	"context"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/box"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/query"
	"zettelstore.de/z/zettel/meta"
)

// -------- List syntax ------------------------------------------------------

import (
	"context"
	"errors"
	"fmt"
	"strings"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/box"
	"zettelstore.de/z/collect"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/query"
	"zettelstore.de/z/strfun"
	"zettelstore.de/z/zettel"

//-----------------------------------------------------------------------------

package usecase

import (
	"context"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/box"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

// Package adapter provides handlers for web requests, and some helper tools.
package adapter

import (
	"context"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/zettel/meta"
)

// TryReIndex executes a re-index if the appropriate query action is given.
func TryReIndex(ctx context.Context, actions []string, metaSeq []*meta.Meta, reIndex *usecase.ReIndex) ([]string, error) {
	if lenActions := len(actions); lenActions > 0 {

import (
	"bytes"
	"context"
	"net/http"
	"time"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/auth"
	"zettelstore.de/z/config"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/web/adapter"
	"zettelstore.de/z/web/server"
	"zettelstore.de/z/zettel/meta"

package api

import (
	"context"
	"net/http"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/usecase"
)

// MakePostCommandHandler creates a new HTTP handler to execute certain commands.
func (a *API) MakePostCommandHandler(
	ucIsAuth *usecase.IsAuthenticated,
	ucRefresh *usecase.Refresh,

//-----------------------------------------------------------------------------

package api

import (
	"net/http"

	"t73f.de/r/sx"
	"t73f.de/r/zsc/api"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/web/adapter"
	"zettelstore.de/z/web/content"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
)

//-----------------------------------------------------------------------------

package api

import (
	"net/http"

	"t73f.de/r/sx"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/zettel/id"
)

// MakeGetDataHandler creates a new HTTP handler to return zettelstore data.
func (a *API) MakeGetDataHandler(ucVersion usecase.Version) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {
		version := ucVersion.Run()
		err := a.writeObject(w, id.Invalid, sx.MakeList(
			sx.Int64(version.Major),
			sx.Int64(version.Minor),
			sx.Int64(version.Patch),
			sx.MakeString(version.Info),
			sx.MakeString(version.Hash),
		))
		if err != nil {
			a.log.Error().Err(err).Msg("Write Version Info")
		}
	}
}

import (
	"bytes"
	"context"
	"fmt"
	"net/http"

	"t73f.de/r/sx"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/sexp"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/box"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/web/adapter"
	"zettelstore.de/z/web/content"

package api

import (
	"net/http"
	"time"

	"t73f.de/r/sx"
	"zettelstore.de/z/auth"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/web/adapter"
	"zettelstore.de/z/zettel/id"
)

// MakePostLoginHandler creates a new HTTP handler to authenticate the given user via API.

			a.log.Error().Err(err).Msg("Write renewed token")
		}
	}
}

func (a *API) writeToken(w http.ResponseWriter, token string, lifetime time.Duration) error {
	return a.writeObject(w, id.Invalid, sx.MakeList(
		sx.MakeString("Bearer"),
		sx.MakeString(token),
		sx.Int64(int64(lifetime/time.Second)),
	))
}

	"fmt"
	"io"
	"net/http"
	"net/url"
	"strconv"
	"strings"

	"t73f.de/r/sx"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/sexp"
	"zettelstore.de/z/query"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/web/adapter"
	"zettelstore.de/z/web/content"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

		})
		msz = sx.Cons(sx.MakeList(symID, sx.Int64(m.Zid)), msz.Cdr()).Cons(symZettel)
		result[i+1] = msz
	}

	_, err := sx.Print(w, sx.MakeList(
		sx.MakeSymbol("meta-list"),
		sx.MakeList(sx.MakeSymbol("query"), sx.MakeString(dze.sq.String())),
		sx.MakeList(sx.MakeSymbol("human"), sx.MakeString(dze.sq.Human())),
		sx.MakeList(result...),
	))
	return err
}
func (dze *dataZettelEncoder) writeArrangement(w io.Writer, act string, arr meta.Arrangement) error {
	result := sx.Nil()
	for aggKey, metaList := range arr {
		sxMeta := sx.Nil()
		for i := len(metaList) - 1; i >= 0; i-- {
			sxMeta = sxMeta.Cons(sx.Int64(metaList[i].Zid))
		}
		sxMeta = sxMeta.Cons(sx.MakeString(aggKey))
		result = result.Cons(sxMeta)
	}
	_, err := sx.Print(w, sx.MakeList(
		sx.MakeSymbol("aggregate"),
		sx.MakeString(act),
		sx.MakeList(sx.MakeSymbol("query"), sx.MakeString(dze.sq.String())),
		sx.MakeList(sx.MakeSymbol("human"), sx.MakeString(dze.sq.Human())),
		result.Cons(sx.SymbolList),
	))
	return err
}

func (a *API) handleTagZettel(w http.ResponseWriter, r *http.Request, tagZettel *usecase.TagZettel, vals url.Values) bool {
	tag := vals.Get(api.QueryKeyTag)

package api

import (
	"net/http"
	"net/url"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/zettel/id"
)

// MakeRenameZettelHandler creates a new HTTP handler to update a zettel.
func (a *API) MakeRenameZettelHandler(renameZettel *usecase.RenameZettel) http.HandlerFunc {
	return func(w http.ResponseWriter, r *http.Request) {

package api

import (
	"io"
	"net/http"
	"net/url"

	"t73f.de/r/sx/sxreader"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	"t73f.de/r/zsc/sexp"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

// getEncoding returns the data encoding selected by the caller.
func getEncoding(r *http.Request, q url.Values) (api.EncodingEnum, string) {

package api

import (
	"bytes"
	"net/http"

	"t73f.de/r/sx"
	"zettelstore.de/z/web/content"
	"zettelstore.de/z/zettel/id"
)

func (a *API) writeObject(w http.ResponseWriter, zid id.Zid, obj sx.Object) error {
	var buf bytes.Buffer
	if _, err := sx.Print(&buf, obj); err != nil {

//-----------------------------------------------------------------------------

package api

import (
	"net/http"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/web/adapter"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
)

// MakeUpdateZettelHandler creates a new HTTP handler to update a zettel.

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

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/query"
)

// GetCredentialsViaForm retrieves the authentication credentions from a form.
func GetCredentialsViaForm(r *http.Request) (ident, cred string, ok bool) {
	err := r.ParseForm()

import (
	"errors"
	"fmt"
	"net/http"
	"strings"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/box"
	"zettelstore.de/z/usecase"
)

// WriteData emits the given data to the response writer.
func WriteData(w http.ResponseWriter, data []byte, contentType string) error {
	if len(data) == 0 {

import (
	"bytes"
	"context"
	"net/http"
	"strings"

	"t73f.de/r/sx"
	"t73f.de/r/zsc/api"
	"zettelstore.de/z/box"
	"zettelstore.de/z/encoder/zmkenc"
	"zettelstore.de/z/evaluator"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/web/adapter"
	"zettelstore.de/z/web/server"

	for _, p := range m.PairsRest() {
		sb.WriteString(p.Key)
		sb.WriteString(": ")
		sb.WriteString(p.Value)
		sb.WriteByte('\n')
	}
	env, rb := wui.createRenderEnv(ctx, "form", wui.rtConfig.Get(ctx, nil, api.KeyLang), title, user)
	rb.bindString("heading", sx.MakeString(title))
	rb.bindString("form-action-url", sx.MakeString(formActionURL))
	rb.bindString("role-data", makeStringList(roleData))
	rb.bindString("syntax-data", makeStringList(syntaxData))
	rb.bindString("meta", sx.MakeString(sb.String()))
	if !ztl.Content.IsBinary() {
		rb.bindString("content", sx.MakeString(ztl.Content.AsString()))
	}
	wui.bindCommonZettelData(ctx, &rb, user, m, &ztl.Content)
	if rb.err == nil {
		rb.err = wui.renderSxnTemplate(ctx, w, id.FormTemplateZid, env)
	}
	if err := rb.err; err != nil {
		wui.reportError(ctx, w, err)

//-----------------------------------------------------------------------------

package webui

import (
	"net/http"

	"t73f.de/r/sx"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/maps"
	"zettelstore.de/z/box"
	"zettelstore.de/z/strfun"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/web/server"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

		m := zs[0].Meta

		user := server.GetUser(ctx)
		env, rb := wui.createRenderEnv(
			ctx, "delete",
			wui.rtConfig.Get(ctx, nil, api.KeyLang), "Delete Zettel "+m.Zid.String(), user)
		if len(zs) > 1 {
			rb.bindString("shadowed-box", sx.MakeString(zs[1].Meta.GetDefault(api.KeyBoxNumber, "???")))
			rb.bindString("incoming", nil)
		} else {
			rb.bindString("shadowed-box", nil)
			rb.bindString("incoming", wui.encodeIncoming(m, wui.makeGetTextTitle(ctx, getZettel)))
		}
		wui.bindCommonZettelData(ctx, &rb, user, m, nil)

	"errors"
	"io"
	"net/http"
	"regexp"
	"strings"
	"unicode"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/web/content"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

import (
	"context"
	"net/http"
	"sort"
	"strings"

	"t73f.de/r/sx"
	"t73f.de/r/zsc/api"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/box"
	"zettelstore.de/z/collect"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/evaluator"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/query"

			return ucEvaluate.RunMetadata(ctx, val)
		}
		pairs := zn.Meta.ComputedPairs()
		metadata := sx.Nil()
		for i := len(pairs) - 1; i >= 0; i-- {
			key := pairs[i].Key
			sxval := wui.writeHTMLMetaValue(key, pairs[i].Value, getTextTitle, evalMeta, enc)
			metadata = metadata.Cons(sx.Cons(sx.MakeString(key), sxval))
		}

		summary := collect.References(zn)
		locLinks, queryLinks, extLinks := wui.splitLocSeaExtLinks(append(summary.Links, summary.Embeds...))

		title := parser.NormalizedSpacedText(zn.InhMeta.GetTitle())
		phrase := q.Get(api.QueryKeyPhrase)

		user := server.GetUser(ctx)
		env, rb := wui.createRenderEnv(ctx, "info", wui.rtConfig.Get(ctx, nil, api.KeyLang), title, user)
		rb.bindString("metadata", metadata)
		rb.bindString("local-links", locLinks)
		rb.bindString("query-links", queryLinks)
		rb.bindString("ext-links", extLinks)
		rb.bindString("unlinked-content", unlinkedContent)
		rb.bindString("phrase", sx.MakeString(phrase))
		rb.bindString("query-key-phrase", sx.MakeString(api.QueryKeyPhrase))
		rb.bindString("enc-eval", wui.infoAPIMatrix(zid, false, encTexts))
		rb.bindString("enc-parsed", wui.infoAPIMatrixParsed(zid, encTexts))
		rb.bindString("shadow-links", shadowLinks)
		wui.bindCommonZettelData(ctx, &rb, user, zn.InhMeta, &zn.Content)
		if rb.err == nil {
			err = wui.renderSxnTemplate(ctx, w, id.InfoTemplateZid, env)
		} else {

		ref := links[i]
		if ref.State == ast.RefStateSelf || ref.IsZettel() {
			continue
		}
		if ref.State == ast.RefStateQuery {
			queries = queries.Cons(
				sx.Cons(
					sx.MakeString(ref.Value),
					sx.MakeString(wui.NewURLBuilder('h').AppendQuery(ref.Value).String())))
			continue
		}
		if ref.IsExternal() {
			extLinks = extLinks.Cons(sx.MakeString(ref.String()))
			continue
		}
		locLinks = locLinks.Cons(sx.Cons(sx.MakeBoolean(ref.IsValid()), sx.MakeString(ref.String())))
	}
	return locLinks, queries, extLinks
}

func createUnlinkedQuery(zid id.Zid, phrase string) *query.Query {
	var sb strings.Builder
	sb.Write(zid.Bytes())

		for je := len(encTexts) - 1; je >= 0; je-- {
			enc := encTexts[je]
			if parseOnly {
				u.AppendKVQuery(api.QueryKeyParseOnly, "")
			}
			u.AppendKVQuery(api.QueryKeyPart, part)
			u.AppendKVQuery(api.QueryKeyEncoding, enc)
			row = row.Cons(sx.Cons(sx.MakeString(enc), sx.MakeString(u.String())))
			u.ClearQuery()
		}
		matrix = matrix.Cons(sx.Cons(sx.MakeString(part), row))
	}
	return matrix
}

func (wui *WebUI) infoAPIMatrixParsed(zid id.Zid, encTexts []string) *sx.Pair {
	matrix := wui.infoAPIMatrix(zid, true, encTexts)
	u := wui.NewURLBuilder('z').SetZid(zid.ZettelID())

	for i, row := 0, matrix; i < len(apiParts) && row != nil; row = row.Tail() {
		line, isLine := sx.GetPair(row.Car())
		if !isLine || line == nil {
			continue
		}
		last := line.LastPair()
		part := apiParts[i]
		u.AppendKVQuery(api.QueryKeyPart, part)
		last = last.AppendBang(sx.Cons(sx.MakeString("plain"), sx.MakeString(u.String())))
		u.ClearQuery()
		if i < 2 {
			u.AppendKVQuery(api.QueryKeyEncoding, api.EncodingData)
			u.AppendKVQuery(api.QueryKeyPart, part)
			last.AppendBang(sx.Cons(sx.MakeString("data"), sx.MakeString(u.String())))
			u.ClearQuery()
		}
		i++
	}
	return matrix
}

func getShadowLinks(ctx context.Context, zid id.Zid, getAllZettel usecase.GetAllZettel) *sx.Pair {
	result := sx.Nil()
	if zl, err := getAllZettel.Run(ctx, zid); err == nil {
		for i := len(zl) - 1; i >= 1; i-- {
			if boxNo, ok := zl[i].Meta.Get(api.KeyBoxNumber); ok {
				result = result.Cons(sx.MakeString(boxNo))
			}
		}
	}
	return result
}

package webui

import (
	"context"
	"net/http"
	"strings"

	"t73f.de/r/sx"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/shtml"
	"zettelstore.de/z/box"
	"zettelstore.de/z/config"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/web/server"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"

		user := server.GetUser(ctx)
		getTextTitle := wui.makeGetTextTitle(ctx, getZettel)

		title := parser.NormalizedSpacedText(zn.InhMeta.GetTitle())
		env, rb := wui.createRenderEnv(ctx, "zettel", wui.rtConfig.Get(ctx, zn.InhMeta, api.KeyLang), title, user)
		rb.bindSymbol(symMetaHeader, metaObj)
		rb.bindString("heading", sx.MakeString(title))
		if role, found := zn.InhMeta.Get(api.KeyRole); found && role != "" {
			rb.bindString("role-url", sx.MakeString(wui.NewURLBuilder('h').AppendQuery(api.KeyRole+api.SearchOperatorHas+role).String()))
		}
		if folgeRole, found := zn.InhMeta.Get(api.KeyFolgeRole); found && folgeRole != "" {
			rb.bindString("folge-role-url", sx.MakeString(wui.NewURLBuilder('h').AppendQuery(api.KeyRole+api.SearchOperatorHas+folgeRole).String()))
		}
		rb.bindString("tag-refs", wui.transformTagSet(api.KeyTags, meta.ListFromValue(zn.InhMeta.GetDefault(api.KeyTags, ""))))
		rb.bindString("predecessor-refs", wui.identifierSetAsLinks(zn.InhMeta, api.KeyPredecessor, getTextTitle))
		rb.bindString("precursor-refs", wui.identifierSetAsLinks(zn.InhMeta, api.KeyPrecursor, getTextTitle))
		rb.bindString("superior-refs", wui.identifierSetAsLinks(zn.InhMeta, api.KeySuperior, getTextTitle))
		rb.bindString("urls", metaURLAssoc(zn.InhMeta))
		rb.bindString("content", content)

}

func metaURLAssoc(m *meta.Meta) *sx.Pair {
	var result sx.ListBuilder
	for _, p := range m.PairsRest() {
		if key := p.Key; strings.HasSuffix(key, meta.SuffixKeyURL) {
			if val := p.Value; val != "" {
				result.Add(sx.Cons(sx.MakeString(capitalizeMetaKey(key)), sx.MakeString(val)))
			}
		}
	}
	return result.List()
}

func (wui *WebUI) bindLinks(ctx context.Context, rb *renderBinder, varPrefix string, m *meta.Meta, key, configKey string, getTextTitle getTextTitleFunc) {

	for i := len(values) - 1; i >= 0; i-- {
		val := values[i]
		zid, err := id.Parse(val)
		if err != nil {
			continue
		}
		if title, found := getTextTitle(zid); found > 0 {
			url := sx.MakeString(wui.NewURLBuilder('h').SetZid(zid.ZettelID()).String())
			if title == "" {
				lst = lst.Cons(sx.Cons(sx.MakeString(val), url))
			} else {
				lst = lst.Cons(sx.Cons(sx.MakeString(title), url))
			}
		}
	}
	return lst
}

package webui

import (
	"net/url"
	"strings"

	"t73f.de/r/sx"
	"t73f.de/r/sxwebs/sxhtml"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/attrs"
	"t73f.de/r/zsc/maps"
	"t73f.de/r/zsc/shtml"
	"t73f.de/r/zsc/sz"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/encoder"
	"zettelstore.de/z/encoder/szenc"
	"zettelstore.de/z/strfun"
	"zettelstore.de/z/zettel/meta"
)

		if hrefP == nil {
			return obj
		}
		href, ok := sx.GetString(hrefP.Cdr())
		if !ok {
			return obj
		}
		zid, fragment, hasFragment := strings.Cut(href.GetValue(), "#")
		u := builder.NewURLBuilder('h').SetZid(api.ZettelID(zid))
		if hasFragment {
			u = u.SetFragment(fragment)
		}
		assoc = assoc.Cons(sx.Cons(shtml.SymAttrHref, sx.MakeString(u.String())))
		return rest.Cons(assoc.Cons(sxhtml.SymAttr)).Cons(shtml.SymA)
	}

	rebind(th, sz.SymLinkZettel, linkZettel)
	rebind(th, sz.SymLinkFound, linkZettel)
	rebind(th, sz.SymLinkBased, func(obj sx.Object) sx.Object {
		attr, assoc, rest := findA(obj)
		if attr == nil {
			return obj
		}
		hrefP := assoc.Assoc(shtml.SymAttrHref)
		if hrefP == nil {
			return obj
		}
		href, ok := sx.GetString(hrefP.Cdr())
		if !ok {
			return obj
		}
		u := builder.NewURLBuilder('/')
		assoc = assoc.Cons(sx.Cons(shtml.SymAttrHref, sx.MakeString(u.String()+href.GetValue()[1:])))
		return rest.Cons(assoc.Cons(sxhtml.SymAttr)).Cons(shtml.SymA)
	})
	rebind(th, sz.SymLinkQuery, func(obj sx.Object) sx.Object {
		attr, assoc, rest := findA(obj)
		if attr == nil {
			return obj
		}
		hrefP := assoc.Assoc(shtml.SymAttrHref)
		if hrefP == nil {
			return obj
		}
		href, ok := sx.GetString(hrefP.Cdr())
		if !ok {
			return obj
		}
		ur, err := url.Parse(href.GetValue())
		if err != nil {
			return obj
		}
		q := ur.Query().Get(api.QueryKeyQuery)
		if q == "" {
			return obj
		}
		u := builder.NewURLBuilder('h').AppendQuery(q)
		assoc = assoc.Cons(sx.Cons(shtml.SymAttrHref, sx.MakeString(u.String())))
		return rest.Cons(assoc.Cons(sxhtml.SymAttr)).Cons(shtml.SymA)
	})
	rebind(th, sz.SymLinkExternal, func(obj sx.Object) sx.Object {
		attr, assoc, rest := findA(obj)
		if attr == nil {
			return obj
		}
		assoc = assoc.Cons(sx.Cons(shtml.SymAttrClass, sx.MakeString("external"))).
			Cons(sx.Cons(shtml.SymAttrTarget, sx.MakeString("_blank"))).
			Cons(sx.Cons(shtml.SymAttrRel, sx.MakeString("noopener noreferrer")))
		return rest.Cons(assoc.Cons(sxhtml.SymAttr)).Cons(shtml.SymA)
	})
	rebind(th, sz.SymEmbed, func(obj sx.Object) sx.Object {
		pair, isPair := sx.GetPair(obj)
		if !isPair || !shtml.SymIMG.IsEqual(pair.Car()) {
			return obj
		}
		attr, isPair := sx.GetPair(pair.Tail().Car())
		if !isPair || !sxhtml.SymAttr.IsEqual(attr.Car()) {
			return obj
		}
		srcP := attr.Tail().Assoc(shtml.SymAttrSrc)
		if srcP == nil {
			return obj
		}
		src, isString := sx.GetString(srcP.Cdr())
		if !isString {
			return obj
		}
		zid := api.ZettelID(src.GetValue())
		if !zid.IsValid() {
			return obj
		}
		u := builder.NewURLBuilder('z').SetZid(zid)
		imgAttr := attr.Tail().Cons(sx.Cons(shtml.SymAttrSrc, sx.MakeString(u.String()))).Cons(sxhtml.SymAttr)
		return pair.Tail().Tail().Cons(imgAttr).Cons(shtml.SymIMG)
	})

	return &htmlGenerator{
		tx:   szenc.NewTransformer(),
		th:   th,
		lang: lang,

package webui

import (
	"context"
	"errors"

	"t73f.de/r/sx"
	"t73f.de/r/sxwebs/sxhtml"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/shtml"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/box"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

func (wui *WebUI) writeHTMLMetaValue(
	key, value string,
	getTextTitle getTextTitleFunc,
	evalMetadata evalMetadataFunc,
	gen *htmlGenerator,
) sx.Object {
	switch kt := meta.Type(key); kt {
	case meta.TypeCredential:
		return sx.MakeString(value)
	case meta.TypeEmpty:
		return sx.MakeString(value)
	case meta.TypeID:
		return wui.transformIdentifier(value, getTextTitle)
	case meta.TypeIDSet:
		return wui.transformIdentifierSet(meta.ListFromValue(value), getTextTitle)
	case meta.TypeNumber:
		return wui.transformKeyValueText(key, value, value)
	case meta.TypeString:
		return sx.MakeString(value)
	case meta.TypeTagSet:
		return wui.transformTagSet(key, meta.ListFromValue(value))
	case meta.TypeTimestamp:
		if ts, ok := meta.TimeValue(value); ok {
			return sx.MakeList(
				sx.MakeSymbol("time"),
				sx.MakeList(
					sxhtml.SymAttr,
					sx.Cons(sx.MakeSymbol("datetime"), sx.MakeString(ts.Format("2006-01-02T15:04:05"))),
				),
				sx.MakeList(sxhtml.SymNoEscape, sx.MakeString(ts.Format("2006-01-02 15:04:05"))),
			)
		}
		return sx.Nil()
	case meta.TypeURL:
		return wui.url2html(sx.MakeString(value))
	case meta.TypeWord:
		return wui.transformKeyValueText(key, value, value)
	case meta.TypeZettelmarkup:
		return wui.transformZmkMetadata(value, evalMetadata, gen)
	default:
		return sx.MakeList(shtml.SymSTRONG, sx.MakeString("Unhandled type: "), sx.MakeString(kt.Name))
	}
}

func (wui *WebUI) transformIdentifier(val string, getTextTitle getTextTitleFunc) sx.Object {
	text := sx.MakeString(val)
	zid, err := id.Parse(val)
	if err != nil {
		return text
	}
	title, found := getTextTitle(zid)
	switch {
	case found > 0:
		ub := wui.NewURLBuilder('h').SetZid(zid.ZettelID())
		attrs := sx.Nil()
		if title != "" {
			attrs = attrs.Cons(sx.Cons(shtml.SymAttrTitle, sx.MakeString(title)))
		}
		attrs = attrs.Cons(sx.Cons(shtml.SymAttrHref, sx.MakeString(ub.String()))).Cons(sxhtml.SymAttr)
		return sx.Nil().Cons(sx.MakeString(zid.String())).Cons(attrs).Cons(shtml.SymA)
	case found == 0:
		return sx.MakeList(sx.MakeSymbol("s"), text)
	default: // case found < 0:
		return text
	}
}

func (wui *WebUI) transformIdentifierSet(vals []string, getTextTitle getTextTitleFunc) *sx.Pair {
	if len(vals) == 0 {
		return nil
	}
	var space = sx.MakeString(" ")
	text := make(sx.Vector, 0, 2*len(vals))
	for _, val := range vals {
		text = append(text, space, wui.transformIdentifier(val, getTextTitle))
	}
	return sx.MakeList(text[1:]...).Cons(shtml.SymSPAN)
}

func (wui *WebUI) transformTagSet(key string, tags []string) *sx.Pair {
	if len(tags) == 0 {
		return nil
	}
	var space = sx.MakeString(" ")
	text := make(sx.Vector, 0, 2*len(tags)+2)
	for _, tag := range tags {
		text = append(text, space, wui.transformKeyValueText(key, tag, tag))
	}
	if len(tags) > 1 {
		text = append(text, space, wui.transformKeyValuesText(key, tags, "(all)"))
	}

}

func buildHref(ub *api.URLBuilder, text string) *sx.Pair {
	return sx.MakeList(
		shtml.SymA,
		sx.MakeList(
			sxhtml.SymAttr,
			sx.Cons(shtml.SymAttrHref, sx.MakeString(ub.String())),
		),
		sx.MakeString(text),
	)
}

type evalMetadataFunc = func(string) ast.InlineSlice

func createEvalMetadataFunc(ctx context.Context, evaluate *usecase.Evaluate) evalMetadataFunc {
	return func(value string) ast.InlineSlice { return evaluate.RunMetadata(ctx, value) }

	"io"
	"net/http"
	"net/url"
	"slices"
	"strconv"
	"strings"

	"t73f.de/r/sx"
	"t73f.de/r/sxwebs/sxhtml"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/shtml"
	"zettelstore.de/z/ast"
	"zettelstore.de/z/encoding/atom"
	"zettelstore.de/z/encoding/rss"
	"zettelstore.de/z/encoding/xml"
	"zettelstore.de/z/evaluator"
	"zettelstore.de/z/query"
	"zettelstore.de/z/usecase"

		user := server.GetUser(ctx)
		env, rb := wui.createRenderEnv(
			ctx, "list",
			wui.rtConfig.Get(ctx, nil, api.KeyLang),
			wui.rtConfig.GetSiteName(), user)
		if q == nil {
			rb.bindString("heading", sx.MakeString(wui.rtConfig.GetSiteName()))
		} else {
			var sb strings.Builder
			q.PrintHuman(&sb)
			rb.bindString("heading", sx.MakeString(sb.String()))
		}
		rb.bindString("query-value", sx.MakeString(q.String()))
		if tzl := q.GetMetaValues(api.KeyTags, false); len(tzl) > 0 {
			sxTzl, sxNoTzl := wui.transformTagZettelList(ctx, tagZettel, tzl)
			if !sx.IsNil(sxTzl) {
				rb.bindString("tag-zettel", sxTzl)
			}
			if !sx.IsNil(sxNoTzl) && wui.canCreate(ctx, user) {
				rb.bindString("create-tag-zettel", sxNoTzl)

		seed, found := q.GetSeed()
		if found {
			apiURL = apiURL.AppendKVQuery(api.QueryKeySeed, strconv.Itoa(seed))
		} else {
			seed = 0
		}
		if len(metaSeq) > 0 {
			rb.bindString("plain-url", sx.MakeString(apiURL.String()))
			rb.bindString("data-url", sx.MakeString(apiURL.AppendKVQuery(api.QueryKeyEncoding, api.EncodingData).String()))
			if wui.canCreate(ctx, user) {
				rb.bindString("create-url", sx.MakeString(wui.createNewURL))
				rb.bindString("seed", sx.Int64(seed))
			}
		}
		if rb.err == nil {
			err = wui.renderSxnTemplate(ctx, w, id.ListTemplateZid, env)
		} else {
			err = rb.err

}

func (wui *WebUI) prependZettelLink(sxZtl *sx.Pair, name string, u *api.URLBuilder) *sx.Pair {
	link := sx.MakeList(
		shtml.SymA,
		sx.MakeList(
			sxhtml.SymAttr,
			sx.Cons(shtml.SymAttrHref, sx.MakeString(u.String())),
		),
		sx.MakeString(name),
	)
	if sxZtl != nil {
		sxZtl = sxZtl.Cons(sx.MakeString(", "))
	}
	return sxZtl.Cons(link)
}

func (wui *WebUI) renderRSS(ctx context.Context, w http.ResponseWriter, q *query.Query, ml []*meta.Meta) {
	var rssConfig rss.Configuration
	rssConfig.Setup(ctx, wui.rtConfig)

package webui

import (
	"context"
	"net/http"

	"t73f.de/r/sx"
	"t73f.de/r/zsc/api"
	"zettelstore.de/z/auth"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/web/adapter"
	"zettelstore.de/z/zettel/id"
)

// MakeGetLoginOutHandler creates a new HTTP handler to display the HTML login view,

package webui

import (
	"fmt"
	"net/http"
	"strings"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/box"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/web/adapter"
	"zettelstore.de/z/web/server"
	"zettelstore.de/z/zettel/id"
)

//-----------------------------------------------------------------------------

package webui

import (
	"net/http"

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

func (wui *WebUI) redirectFound(w http.ResponseWriter, r *http.Request, ub *api.URLBuilder) {
	us := ub.String()
	wui.log.Debug().Str("uri", us).Msg("redirect")
	http.Redirect(w, r, us, http.StatusFound)
}

package webui

import (
	"context"
	"fmt"
	"io"

	"t73f.de/r/sx/sxeval"
	"t73f.de/r/zsc/api"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

func (wui *WebUI) loadAllSxnCodeZettel(ctx context.Context) (id.Digraph, *sxeval.Binding, error) {
	// getMeta MUST currently use GetZettel, because GetMeta just uses the
	// Index, which might not be current.

import (
	"bytes"
	"context"
	"fmt"
	"net/http"
	"net/url"

	"t73f.de/r/sx"
	"t73f.de/r/sx/sxbuiltins"
	"t73f.de/r/sx/sxeval"
	"t73f.de/r/sx/sxreader"
	"t73f.de/r/sxwebs/sxhtml"
	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/shtml"
	"zettelstore.de/z/box"
	"zettelstore.de/z/collect"
	"zettelstore.de/z/config"
	"zettelstore.de/z/parser"
	"zettelstore.de/z/web/adapter"
	"zettelstore.de/z/web/server"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

func (wui *WebUI) createRenderBinding() *sxeval.Binding {
	root := sxeval.MakeRootBinding(len(specials) + len(builtins) + 3)
	for _, syntax := range specials {
		root.BindSpecial(syntax)
	}
	for _, b := range builtins {
		root.BindBuiltin(b)
	}
	_ = root.Bind(sx.MakeSymbol("NIL"), sx.Nil())
	_ = root.Bind(sx.MakeSymbol("T"), sx.MakeSymbol("T"))
	root.BindBuiltin(&sxeval.Builtin{
		Name:     "url-to-html",
		MinArity: 1,
		MaxArity: 1,
		TestPure: sxeval.AssertPure,
		Fn1: func(_ *sxeval.Environment, arg sx.Object) (sx.Object, error) {
			text, err := sxbuiltins.GetString(arg, 0)
			if err != nil {
				return nil, err
			}
			return wui.url2html(text), nil
		},
	})
	root.BindBuiltin(&sxeval.Builtin{
		Name:     "zid-content-path",
		MinArity: 1,
		MaxArity: 1,
		TestPure: sxeval.AssertPure,
		Fn1: func(_ *sxeval.Environment, arg sx.Object) (sx.Object, error) {
			s, err := sxbuiltins.GetString(arg, 0)
			if err != nil {
				return nil, err
			}
			zid, err := id.Parse(s.GetValue())
			if err != nil {
				return nil, fmt.Errorf("parsing zettel identifier %q: %w", s.GetValue(), err)
			}
			ub := wui.NewURLBuilder('z').SetZid(zid.ZettelID())
			return sx.MakeString(ub.String()), nil
		},
	})
	root.BindBuiltin(&sxeval.Builtin{
		Name:     "query->url",
		MinArity: 1,
		MaxArity: 1,
		TestPure: sxeval.AssertPure,
		Fn1: func(_ *sxeval.Environment, arg sx.Object) (sx.Object, error) {
			qs, err := sxbuiltins.GetString(arg, 0)
			if err != nil {
				return nil, err
			}
			u := wui.NewURLBuilder('h').AppendQuery(qs.GetValue())
			return sx.MakeString(u.String()), nil
		},
	})
	root.Freeze()
	return root
}

var (
	specials = []*sxeval.Special{
		&sxbuiltins.QuoteS, &sxbuiltins.QuasiquoteS, // quote, quasiquote
		&sxbuiltins.UnquoteS, &sxbuiltins.UnquoteSplicingS, // unquote, unquote-splicing
		&sxbuiltins.DefVarS,                     // defvar
		&sxbuiltins.DefunS, &sxbuiltins.LambdaS, // defun, lambda
		&sxbuiltins.SetXS,     // set!
		&sxbuiltins.IfS,       // if
		&sxbuiltins.BeginS,    // begin
		&sxbuiltins.DefMacroS, // defmacro
		&sxbuiltins.LetS,      // let
	}
	builtins = []*sxeval.Builtin{
		&sxbuiltins.Equal,                // =
		&sxbuiltins.NumGreater,           // >
		&sxbuiltins.NullP,                // null?
		&sxbuiltins.PairP,                // pair?
		&sxbuiltins.Car, &sxbuiltins.Cdr, // car, cdr

		&sxbuiltins.Defined,        // defined?
		&sxbuiltins.CurrentBinding, // current-binding
		&sxbuiltins.BindingLookup,  // binding-lookup
	}
)

func (wui *WebUI) url2html(text sx.String) sx.Object {
	if u, errURL := url.Parse(text.GetValue()); errURL == nil {
		if us := u.String(); us != "" {
			return sx.MakeList(
				shtml.SymA,
				sx.MakeList(
					sxhtml.SymAttr,
					sx.Cons(shtml.SymAttrHref, sx.MakeString(us)),
					sx.Cons(shtml.SymAttrTarget, sx.MakeString("_blank")),
					sx.Cons(shtml.SymAttrRel, sx.MakeString("noopener noreferrer")),
				),
				text)
		}
	}
	return text
}

// createRenderEnv creates a new environment and populates it with all relevant data for the base template.
func (wui *WebUI) createRenderEnv(ctx context.Context, name, lang, title string, user *meta.Meta) (*sxeval.Binding, renderBinder) {
	userIsValid, userZettelURL, userIdent := wui.getUserRenderData(user)
	parentEnv, err := wui.getParentEnv(ctx)
	bind := parentEnv.MakeChildBinding(name, 128)
	rb := makeRenderBinder(bind, err)
	rb.bindString("lang", sx.MakeString(lang))
	rb.bindString("css-base-url", sx.MakeString(wui.cssBaseURL))
	rb.bindString("css-user-url", sx.MakeString(wui.cssUserURL))
	rb.bindString("title", sx.MakeString(title))
	rb.bindString("home-url", sx.MakeString(wui.homeURL))
	rb.bindString("with-auth", sx.MakeBoolean(wui.withAuth))
	rb.bindString("user-is-valid", sx.MakeBoolean(userIsValid))
	rb.bindString("user-zettel-url", sx.MakeString(userZettelURL))
	rb.bindString("user-ident", sx.MakeString(userIdent))
	rb.bindString("login-url", sx.MakeString(wui.loginURL))
	rb.bindString("logout-url", sx.MakeString(wui.logoutURL))
	rb.bindString("list-zettel-url", sx.MakeString(wui.listZettelURL))
	rb.bindString("list-roles-url", sx.MakeString(wui.listRolesURL))
	rb.bindString("list-tags-url", sx.MakeString(wui.listTagsURL))
	if wui.canRefresh(user) {
		rb.bindString("refresh-url", sx.MakeString(wui.refreshURL))
	}
	rb.bindString("new-zettel-links", wui.fetchNewTemplatesSxn(ctx, user))
	rb.bindString("search-url", sx.MakeString(wui.searchURL))
	rb.bindString("query-key-query", sx.MakeString(api.QueryKeyQuery))
	rb.bindString("query-key-seed", sx.MakeString(api.QueryKeySeed))
	rb.bindString("FOOTER", wui.calculateFooterSxn(ctx)) // TODO: use real footer
	rb.bindString("debug-mode", sx.MakeBoolean(wui.debug))
	rb.bindSymbol(symMetaHeader, sx.Nil())
	rb.bindSymbol(symDetail, sx.Nil())
	return bind, rb
}

}
func (rb *renderBinder) bindSymbol(sym *sx.Symbol, obj sx.Object) {
	if rb.err == nil {
		rb.err = rb.binding.Bind(sym, obj)
	}
}
func (rb *renderBinder) bindKeyValue(key string, value string) {
	rb.bindString("meta-"+key, sx.MakeString(value))
	if kt := meta.Type(key); kt.IsSet {
		rb.bindString("set-meta-"+key, makeStringList(meta.ListFromValue(value)))
	}
}
func (rb *renderBinder) rebindResolved(key, defKey string) {
	if rb.err == nil {
		if obj, found := rb.binding.Resolve(sx.MakeSymbol(key)); found {
			rb.bindString(defKey, obj)
		}
	}
}

func (wui *WebUI) bindCommonZettelData(ctx context.Context, rb *renderBinder, user, m *meta.Meta, content *zettel.Content) {
	strZid := m.Zid.String()
	apiZid := api.ZettelID(strZid)
	newURLBuilder := wui.NewURLBuilder

	rb.bindString("zid", sx.MakeString(strZid))
	rb.bindString("web-url", sx.MakeString(newURLBuilder('h').SetZid(apiZid).String()))
	if content != nil && wui.canWrite(ctx, user, m, *content) {
		rb.bindString("edit-url", sx.MakeString(newURLBuilder('e').SetZid(apiZid).String()))
	}
	rb.bindString("info-url", sx.MakeString(newURLBuilder('i').SetZid(apiZid).String()))
	if wui.canCreate(ctx, user) {
		if content != nil && !content.IsBinary() {
			rb.bindString("copy-url", sx.MakeString(newURLBuilder('c').SetZid(apiZid).AppendKVQuery(queryKeyAction, valueActionCopy).String()))
		}
		rb.bindString("version-url", sx.MakeString(newURLBuilder('c').SetZid(apiZid).AppendKVQuery(queryKeyAction, valueActionVersion).String()))
		rb.bindString("child-url", sx.MakeString(newURLBuilder('c').SetZid(apiZid).AppendKVQuery(queryKeyAction, valueActionChild).String()))
		rb.bindString("folge-url", sx.MakeString(newURLBuilder('c').SetZid(apiZid).AppendKVQuery(queryKeyAction, valueActionFolge).String()))
	}
	if wui.canRename(ctx, user, m) {
		rb.bindString("rename-url", sx.MakeString(newURLBuilder('b').SetZid(apiZid).String()))
	}
	if wui.canDelete(ctx, user, m) {
		rb.bindString("delete-url", sx.MakeString(newURLBuilder('d').SetZid(apiZid).String()))
	}
	if val, found := m.Get(api.KeyUselessFiles); found {
		rb.bindString("useless", sx.Cons(sx.MakeString(val), nil))
	}
	queryContext := strZid + " " + api.ContextDirective
	rb.bindString("context-url", sx.MakeString(newURLBuilder('h').AppendQuery(queryContext).String()))
	queryContext += " " + api.FullDirective
	rb.bindString("context-full-url", sx.MakeString(newURLBuilder('h').AppendQuery(queryContext).String()))
	if wui.canRefresh(user) {
		rb.bindString("reindex-url", sx.MakeString(newURLBuilder('h').AppendQuery(
			strZid+" "+api.IdentDirective+api.ActionSeparator+api.ReIndexAction).String()))
	}

	// Ensure to have title, role, tags, and syntax included as "meta-*"
	rb.bindKeyValue(api.KeyTitle, m.GetDefault(api.KeyTitle, ""))
	rb.bindKeyValue(api.KeyRole, m.GetDefault(api.KeyRole, ""))
	rb.bindKeyValue(api.KeyTags, m.GetDefault(api.KeyTags, ""))
	rb.bindKeyValue(api.KeySyntax, m.GetDefault(api.KeySyntax, meta.DefaultSyntax))
	var metaPairs sx.ListBuilder
	for _, p := range m.ComputedPairs() {
		key, value := p.Key, p.Value
		metaPairs.Add(sx.Cons(sx.MakeString(key), sx.MakeString(value)))
		rb.bindKeyValue(key, value)
	}
	rb.bindString("metapairs", metaPairs.List())
}

func (wui *WebUI) fetchNewTemplatesSxn(ctx context.Context, user *meta.Meta) (lst *sx.Pair) {
	if !wui.canCreate(ctx, user) {

		z, err2 := wui.box.GetZettel(ctx, zid)
		if err2 != nil {
			continue
		}
		if !wui.policy.CanRead(user, z.Meta) {
			continue
		}
		text := sx.MakeString(parser.NormalizedSpacedText(z.Meta.GetTitle()))
		link := sx.MakeString(wui.NewURLBuilder('c').SetZid(zid.ZettelID()).
			AppendKVQuery(queryKeyAction, valueActionNew).String())

		lst = lst.Cons(sx.Cons(text, link))
	}
	return lst
}
func (wui *WebUI) calculateFooterSxn(ctx context.Context) *sx.Pair {

		return err
	}
	if msg := wui.log.Debug(); msg != nil {
		// pageObj.String() can be expensive to calculate.
		msg.Str("page", pageObj.String()).Msg("render")
	}

	gen := sxhtml.NewGenerator().SetNewline()
	var sb bytes.Buffer
	_, err = gen.WriteHTML(&sb, pageObj)
	if err != nil {
		return err
	}
	wui.prepareAndWriteHeader(w, code)
	if _, err = w.Write(sb.Bytes()); err != nil {

	if code == http.StatusInternalServerError {
		wui.log.Error().Msg(err.Error())
	} else {
		wui.log.Debug().Err(err).Msg("reportError")
	}
	user := server.GetUser(ctx)
	env, rb := wui.createRenderEnv(ctx, "error", api.ValueLangEN, "Error", user)
	rb.bindString("heading", sx.MakeString(http.StatusText(code)))
	rb.bindString("message", sx.MakeString(text))
	if rb.err == nil {
		rb.err = wui.renderSxnTemplateStatus(ctx, w, code, id.ErrorTemplateZid, env)
	}
	errSx := rb.err
	if errSx == nil {
		return
	}

func makeStringList(sl []string) *sx.Pair {
	if len(sl) == 0 {
		return nil
	}
	result := sx.Nil()
	for i := len(sl) - 1; i >= 0; i-- {
		result = result.Cons(sx.MakeString(sl[i]))
	}
	return result
}

import (
	"context"
	"net/http"
	"sync"
	"time"

	"t73f.de/r/sx"
	"t73f.de/r/sx/sxeval"
	"t73f.de/r/sxwebs/sxhtml"
	"t73f.de/r/zsc/api"
	"zettelstore.de/z/auth"
	"zettelstore.de/z/box"
	"zettelstore.de/z/config"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/usecase"
	"zettelstore.de/z/web/adapter"

		withAuth:      authz.WithAuth(),
		loginURL:      loginoutBase.String(),
		logoutURL:     loginoutBase.AppendKVQuery("logout", "").String(),
		searchURL:     ab.NewURLBuilder('h').String(),
		createNewURL:  ab.NewURLBuilder('c').String(),

		zettelBinding: nil,
		genHTML:       sxhtml.NewGenerator().SetNewline(),
	}
	wui.rootBinding = wui.createRenderBinding()
	wui.observe(box.UpdateInfo{Box: mgr, Reason: box.OnReload, Zid: id.Invalid})
	mgr.RegisterObserver(wui.observe)
	return wui
}

// It translates syntax values into content types, and vice versa.
package content

import (
	"mime"
	"net/http"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/zettel"
	"zettelstore.de/z/zettel/meta"
)

const (
	UnknownMIME  = "application/octet-stream"
	mimeGIF      = "image/gif"

package impl

import (
	"context"
	"net/http"
	"time"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/auth"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/web/server"
	"zettelstore.de/z/zettel/meta"
)

type myServer struct {

import (
	"io"
	"net/http"
	"regexp"
	"strings"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/auth"
	"zettelstore.de/z/kernel"
	"zettelstore.de/z/logger"
	"zettelstore.de/z/web/server"
)

type (

package server

import (
	"context"
	"net/http"
	"time"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

// UserRetriever allows to retrieve user data based on a given zettel identifier.
type UserRetriever interface {
	GetUser(ctx context.Context, zid id.Zid, ident string) (*meta.Meta, error)

* `go run tools/devtools/devtools.go` install all needed software (see above).
* `go run tools/htmllint/htmllint.go [URL]` checks all generated HTML of a
  Zettelstore accessible at the given URL (default: http://localhost:23123).
* `go run tools/testapi/testapi.go` tests the API against a running
  Zettelstore, which is started automatically.

## A note on the use of Fossil
Zettelstore is managed by the Fossil version control system. Fossil is an
alternative to the ubiquitous Git version control system. However, Go seems to
prefer Git and popular platforms that just support Git.

Some dependencies of Zettelstore, namely [Zettelstore
client](https://t73f.de/r/zsc) and [Sx](https://t73f.de/r/sx), are also

managed by Fossil. Depending on your development setup, some error messages
might occur.

If the error message mentions an environment variable called `GOVCS` you should
set it to the value `GOVCS=zettelstore.de:fossil` (alternatively more generous

to `GOVCS=*:all`). Since the Go build system is coupled with Git and some
special platforms, you allow ot to download a Fossil repository from the host
`zettelstore.de`. The build tool set `GOVCS` to the right value, but you may
use other `go` commands that try to download a Fossil repository.

On some operating systems, namely Termux on Android, an error message might
state that an user cannot be determined (`cannot determine user`). In this
case, Fossil is allowed to download the repository, but cannot associate it

with an user name. Set the environment variable `USER` to any user name, like:
`USER=nobody go run tools/build.go build`.

<title>Change Log</title>

<a id="0_18"></a>
<h2>Changes for Version 0.18.0 (pending)</h2>
  *  Remove Sx macro <code>defunconst</code>. Use <code>defun</code> instead.
     (breaking: webui)
  *  New zettel are now created with the permission for others to read/write
     them. This is important especially for Unix-like systems. If you want the
     previous behaviour, set <code>umask</code> accordingly, for example
     <code>umask 066</code>.
     (major: dirbox)
  *  Update Sx prelude: make macros more robust / more general. This might
     break your code in the future.
     (minor: webui)
  *  Add computed zettel &ldquo;Zettelstore Memory&rdquo; with zettel
     identifier <code>00000000000008</code>. It shows some statistics about
     memory usage.
     (minor: webui)
  *  Zettelstore client is now Go package t73f.de/r/zsc.
     (minor)

<a id="0_17"></a>
<h2>Changes for Version 0.17.0 (2024-03-04)</h2>
  *  Context search operates only on explicit references. Add the directive
     <code>FULL</code> to follow zettel tags additionally.
     (breaking)
  *  Context cost calculation has been changed. Prepare to retrieve different

     (breaking: webui)
  *  Allow to determine a role zettel for a given role.
     (major: api, webui)
  *  Present user the option to create a (missing) role zettel (in list view).
     Results in a new predefined zettel with identifier 00000000090004, which
     is a template for new role zettel.
     (minor: webui)
  *  Timestamp values can be abbreviated by omitting most of its components.
     Previously, such values that are not in the format YYYYMMDDhhmmss were
     ignored. Now the following formats are also allowed: YYYY, YYYYMM,
     YYYYMMDD, YYYYMMDDhh, YYYYMMDDhhmm. Querying and sorting work accordingly.
     Previously, only a sequences of zeroes were appended, resulting in illegal
     timestamps, e.g. for YYYY or YYYYMM.
     (minor)
  *  SHTML encoder fixed w.r.t inline quoting. Previously, an <q> tag was

     (minor: webui)
  *  ZIP file with manual now contains a zettel 00001000000000 that contains
     its build date (metadata key <code>created</code>) and version (in the
     zettel content)
     (minor)
  *  If an error page cannot be created due to template errors (or similar), a
     plain text error page is delivered instead. It shows the original error
     and the error that occurred during rendering the original error page.
     (minor: webui)
  *  Some smaller bug fixes and improvements, to the software and to the
     documentation.

<a id="0_14"></a>
<h2>Changes for Version 0.14.0 (2023-09-22)</h2>
  *  Remove support for JSON. This was marked deprecated in version 0.12.0. Use

  *  Remove ZJSON encoding. It was announced in version 0.10.0. Use Sexpr
     encoding instead.
     (breaking)
  *  Title of a zettel is no longer interpreted as Zettelmarkup text. Now it is
     just a plain string, possibly empty. Therefore, no inline formatting (like
     bold text), no links, no footnotes, no citations (the latter made
     rendering the title often questionable, in some contexts). If you used
     special entities, please use the Unicode characters directly. However, as
     a good practice, it is often the best to printable ASCII characters.
     (breaking)
  *  Remove runtime configuration <code>marker-external</code>. It was added in
     version [#0_0_6|0.0.6] and updated in [#0_0_10|0.0.10]. If you want to
     change the marker for an external URL, you could modify zettel
     00000000020001 (Zettelstore Base CSS) or zettel 00000000025001
     (Zettelstore User CSS, preferred) by changing / adding a rule to add some

     (minor: api)
  *  Enhance zettel context by raising the importance of folge zettel (and
     similar).
     (minor: api, webui)
  *  Interpret zettel files with extension <code>.webp</code> as an binary
     image file format.
     (minor)
  *  Allow to specify service specific log level via startup configuration and
     via command line.
     (minor)
  *  Allow to specify a zettel to serve footer content via runtime
     configuration <code>footer-zettel</code>. Can be overwritten by user
     zettel.
     (minor: webui)
  *  Footer data is automatically separated by a thematic break / horizontal
     rule. If you do not like it, you have to update the base template.
     (minor: webui)
  *  Allow to set runtime configuration <code>home-zettel</code> in the user
     zettel to make it user-specific.
     (minor: webui)
  *  Serve favicon.ico from the asset directory.
     (minor: webui)
  *  Zettelmarkup cheat sheet
     (minor: manual)
  *  Runtime configuration key <code>footer-html</code> will be removed in
     Version 0.10.0. Please use <code>footer-zettel</code> instead.
     (deprecated: webui)
  *  In the next version 0.10.0, the API endpoints for a zettel
     (<code>/j</code>, <code>/p</code>, <code>/v</code>) will be merged with
     endpoint <code>/z</code>. Basically, the previous endpoint will be
     refactored as query parameter of endpoint <code>/z</code>. To reduce
     errors, there will be no version, where the previous endpoint are still
     available and the new functionality is still there. This is a warning to
     prepare for some breaking changes in v0.10.0. This also affects the API
     client implementation.
     (warning: api)
  *  Some smaller bug fixes and improvements, to the software and to the
     documentation.

<a id="0_8"></a>

  *  Query results can be ordered for more than one metadata key. Ordering by
     zettel identifier is an implicit last order expression to produce stable
     results.
     (minor: api, webui)
  *  Add support for an asset directory, accessible via URL prefix
     <code>/assests/</code>.
     (minor: server)
  *  Add support for metadata key <code>created</code>, a time stamp when the
     zettel was created. Since key <code>published</code> is now either
     <code>created</code> or <code>modified</code>, it will now always contains
     a valid time stamp.
     (minor)
  *  Add support for metadata key <code>author</code>. It will be displayed on
     a zettel, if set.
     (minor: webui)
  *  Remove CSS for lists. The browsers default value for
     <code>padding-left</code> will be used.
     (minor: webui)
  *  Removed templates for rendering roles and tags lists. This is now done by
     query actions.
     (minor: webui)
  *  Tags within zettel content are deprecated in version 0.8. This affects the
     computed metadata keys <code>content-tags</code> and
     <code>all-tags</code>. They will be removed. The number sign of a content
     tag introduces unintended tags, esp. in the English language; content tags
     may occur within links &rarr; links within links, when rendered as HTML;
     content tags may occur in the title of a zettel; naming of content tags,
     zettel tags, and their union is confusing for many. Migration: use zettel
     tags or replace content tag with a search.
     (deprecated: zettelmarkup)
  *  Cleanup names for HTTP query parameter for API calls. Essentially,
     underscore characters in front are removed. Please use new names, old

     (bug)

<h2>Changes for Version 0.6.0 (2022-08-11)</h2>
  *  Translating of "..." into horizontal ellipsis is no longer supported. Use
     &amp;hellip; instead.
     (breaking: zettelmarkup)
  *  Allow to specify search expressions, which allow to specify search
     criteria by using a simple syntax. Can be specified in WebUI's search box
     and via the API by using query parameter "_s".
     (major: api, webui)
  *  A link reference is allowed to be a search expression. The WebUI will
     render this as a link to a list of zettel that satisfy the search
     expression.
     (major: zettelmarkup, webui)
  *  A block transclusion is allowed to specify a search expression. When
     evaluated, the transclusion is replaced by a list of zettel that satisfy
     the search expression.
     (major: zettelmarkup)
  *  When presenting a zettel list, allow to change the search expression.
     (minor: webui)
  *  When evaluating a zettel, ignore transclusions if current user is not
     allowed to read transcluded zettel.
     (minor)
  *  Added a small tutorial for Zettelmarkup.
     (minor: manual)
  *  Using URL query parameter to search for metadata values, specify an
     ordering, an offset, and a limit for the resulting list, will be removed
     in version 0.7. Replace these with the more useable search expressions.
     Please be aware that the = search operator is also deprecated. It was only
     introduced to help the migration.
     (deprecated: api, webui)
  *  Some smaller bug fixes and improvements, to the software and to the
     documentation.

     Zettelstore WebUI.
     (minor: webui)
  *  A zettel can be saved while creating / editing it. There is no need to
     manually re-edit it by using the 'e' endpoint.
     (minor: webui)
  *  Zettel role and zettel syntax are backed by a HTML5 data list element
     which lists supported and used values to help to enter a valid value.
     (minor: webui)
  *  Allow to use startup configuration, even if started in simple mode.
     (minor)
  *  Log authentication issues in level "sense"; add caller IP address to some
     web server log messages.
     (minor: web server)
  *  New startup configuration key <kbd>max-request-size</kbd> to limit a web
     request body to prevent client sending too large requests.
     (minor: web server)
  *  Many smaller bug fixes and improvements, to the software and to the
     documentation.

<a id="0_4"></a>
<h2>Changes for Version 0.4 (2022-03-08)</h2>
  *  Encoding &ldquo;djson&rdquo; renamed to &ldquo;zjson&rdquo; (<em>zettel
     json</em>).
     (breaking: api; minor: webui)
  *  Remove inline quotation syntax <code>&lt;&lt;...&lt;&lt;</code>. Now,
     <code>&quot;&quot;...&quot;&quot;</code> generates the equivalent code.
     Typographical quotes are generated by the browser, not by Zettelstore.
     (breaking: Zettelmarkup)
  *  Remove inline formatting for mono space. Its syntax is now used by the
     similar syntax element of literal computer input. Mono space was just
     a visual element with no semantic association. Now, the syntax
     <kbd>++...++</kbd> is obsolete.
     (breaking: Zettelmarkup).
  *  Remove API call to parse Zettelmarkup texts and encode it as text and
     HTML. Was call &ldquo;POST /v&rdquo;. It was needed to separately encode
     the titles of zettel. The same effect can be achieved by fetching the
     ZJSON representation and encode it using the function in the Zettelstore

     (minor: webui)
  *  Remove support for metadata key <code>no-index</code> to suppress indexing
     selected zettel. It was introduced in <a href="#0_0_11">v0.0.11</a>, but
     disallows some future optimizations for searching zettel.
     (minor: api, webui)
  *  Make some metadata-based searches a little bit faster by executing
     a (in-memory-based) full-text search first. Now only those zettel are
     loaded from file that contain the metadata value.
     (minor: api, webui)
  *  Add an API call to retrieve the version of the Zettelstore.
     (minor: api)
  *  Limit the amount of zettel and bytes to be stored in a memory box. Allows
     to use it with public access.
     (minor: box)
  *  Disallow to cache the authentication cookie. Will remove most unexpected
     log-outs when using a mobile device.
     (minor: webui)
  *  Many smaller bug fixes and improvements, to the software and to the
     documentation.

<a id="0_3"></a>
<h2>Changes for Version 0.3 (2022-02-09)</h2>
  *  Zettel files with extension <code>.meta</code> are now treated as content
     files. Previously, they were interpreted as metadata files. The
     interpretation as metadata files was deprecated in version 0.2.
     (breaking: directory and file/zip box)
  *  Add syntax &ldquo;draw&rdquo; to produce some graphical representations.
     (major)
  *  Add Zettelmarkup syntax to specify full transclusion of other zettel.
     (major: Zettelmarkup)
  *  Add Zettelmarkup syntax to specify inline-zettel, both for

     (minor)
  *  Add computed zettel that lists all supported parser / recognized zettel
     syntaxes.
     (minor)
  *  Add API call to check for enabled authentication.
     (minor: api)
  *  Renewing an API access token works even if authentication is not enabled.
     This corresponds to the behaviour of obtaining an access token.
     (minor: api)
  *  If there is nothing to return, use HTTP status code 204, instead of 200 +
     <code>Content-Length: 0</code>.
     (minor: api)
  *  Metadata key <code>duplicates</code> stores the duplicate file names,
     instead of just a boolean value that there were duplicate file names.
     (minor)
  *  Document auto starting Zettelstore on Windows, macOS, and Linux.
     (minor)
  *  Many smaller bug fixes and improvements, to the software and to the
     documentation.

<a id="0_1"></a><a id="0_1_0"></a>
<h2>Changes for Version 0.1 (2021-11-11)</h2>
  *  v0.1.3 (2021-12-15) fixes a bug where the modification date could be set

     syntax will not be supported. The reason is the collision with URLs that
     also contain the characters <code>//</code>. The ZMK encoding of a zettel
     may help with the transition
     (<code>/v/{ZettelID}?_part=zettel&amp;_enc=zmk</code>, on the Info page of
     each zettel in the WebUI). Additionally, all deprecated uses of
     <code>//</code> will be rendered with a dashed box within the WebUI.
     (breaking: Zettelmarkup).
  *  API client software is now a separate project.

     (breaking)
  *  Initial support for HTTP security headers (Content-Security-Policy,
     Permissions-Policy, Referrer-Policy, X-Content-Type-Options,
     X-Frame-Options). Header values are currently some constant values.
     (possibly breaking: api, webui)
  *  Remove visual Zettelmarkup (bold, strike through). Semantic Zettelmarkup
     (strong, delete) is still allowed and replaces the visual elements
     syntactically. The visual appearance should not change (depends on your
     changes / additions to CSS zettel).
     (possibly breaking: Zettelmarkup).
  *  Add API endpoint <code>POST /v</code> to retrieve HTMl and text encoded
     strings from given ZettelMarkup encoded values. This will be used to
     render a HTML page from a given zettel: in many cases the title of

     translated to their lower case equivalent before comparing them and when
     you edit a zettel through Zettelstore. If you just modify the zettel
     files, your tag values remain unchanged.
     (major; breaking)
  *  Endpoint <code>/z/{ID}</code> allows the same methods as endpoint
     <code>/j/{ID}</code>: <code>GET</code> retrieves zettel (see above),
     <code>PUT</code> updates a zettel, <code>DELETE</code> deletes a zettel,
     <code>MOVE</code> renames a zettel. In addition, <code>POST /z</code> will
     create a new zettel. When zettel data must be given, the format is plain
     text, with metadata separated from content by an empty line. See
     documentation for more details.
     (major: api (plus WebUI for some details))
  *  Allows to transclude / expand the content of another zettel into a target
     zettel when the zettel is rendered. By using the syntax of embedding an
     image (which is some kind of expansion too), the first top-level paragraph

     above suffixes, but as a string type)
  *  New <code>user-role</code> &ldquo;creator&rdquo;, which is only allowed to
     create new zettel (except user zettel). This role may only read and update
     public zettel or its own user zettel. Added to support future client
     software (e.g. on a mobile device) that automatically creates new zettel
     but, in case of a password loss, should not allow to read existing zettel.
     (minor, possibly breaking, because new zettel template zettel must always
     prepend the string <code>new-</code> before metadata keys that should be
     transferred to the new zettel)
  *  New supported metadata key <code>box-number</code>, which gives an
     indication from which box the zettel was loaded.
     (minor)
  *  New supported syntax <code>html</code>.
     (minor)
  *  New predefined zettel &ldquo;User CSS&rdquo; that can be used to redefine
     some predefined CSS (without modifying the base CSS zettel).
     (minor: webui)

  *  Many smaller bug fixes and improvements, to the software and to the
     documentation.

A note for users of macOS: in the current release and with macOS's default
values, a zettel directory must not contain more than approx. 250 files. There
are three options to mitigate this limitation temporarily:
  #  You update the per-process limit of open files on macOS.
  #  You setup a virtualisation environment to run Zettelstore on Linux or
     Windows.
  #  You wait for version 0.0.12 which addresses this issue.

<a id="0_0_10"></a>
<h2>Changes for Version 0.0.10 (2021-02-26)</h2>
  *  Menu item &ldquo;Home&rdquo; now redirects to a home zettel.
     Its default identifier is <code>000100000000</code>. The identifier can be

  *  (bug)   Fixes a memory leak that results in too many open files after
             approx. 125 reload operations.
  *  (major) Predefined templates for new zettel got an explicit value for
             visibility: “login”. Please update these zettel if you
             modified them.
  *  (major) Rename key <code>readonly</code> of <i>Zettelstore Startup
             Configuration</i> to <code>read-only-mode</code>. This was done to
             avoid some confusion with the zettel metadata key
             <code>read-only</code>. <b>Please adapt your startup
             configuration. Otherwise your Zettelstore will be accidentally
             writable.</b>
  *  (minor) References starting with &ldquo;./&rdquo; and &ldquo;../&rdquo;
             are treated as a local reference. Previously, only the prefix
             &ldquo;/&rdquo; was treated as a local reference.
  *  (major) Metadata key <code>modified</code> will be set automatically to
             the current local time if a zettel is updated through Zettelstore.
             <b>If you used that key previously for your own, you should rename
             it before you upgrade.</b>

To get an initial impression, take a look at the
[https://zettelstore.de/manual/|manual]. It is a live example of the
zettelstore software, running in read-only mode.

The software, including the manual, is licensed under the
[/file?name=LICENSE.txt&ci=trunk|European Union Public License 1.2 (or later)].

  *  [https://t73f.de/r/zsc|Zettelstore Client] provides client software to
     access Zettelstore via its API more easily.
  *  [https://zettelstore.de/contrib|Zettelstore Contrib] contains contributed
     software, which often connects to Zettelstore via its API. Some of the
     software packages may be experimental.
  *  [https://t73f.de/r/sx|Sx] provides an evaluator for symbolic
     expressions, which is used for HTML templates and more.

[https://mastodon.social/tags/Zettelstore|Stay tuned] …
<hr>
<h3>Latest Release: 0.17.0 (2024-03-04)</h3>
  *  [./download.wiki|Download]
  *  [./changes.wiki#0_17|Change summary]
  *  [/timeline?p=v0.17.0&bt=v0.16.0&y=ci|Check-ins for version 0.17.0],

	"bytes"
	"encoding/base64"
	"errors"
	"io"
	"unicode"
	"unicode/utf8"

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

// Content is just the content of a zettel.
type Content struct {
	data     []byte
	isBinary bool
}

// zettel identifier.
package id

import (
	"strconv"
	"time"

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

// Zid is the internal identifier of a zettel. Typically, it is a
// time stamp of the form "YYYYMMDDHHmmSS" converted to an unsigned integer.
// A zettelstore implementation should try to set the last two digits to zero,
// e.g. the seconds should be zero,
type Zid uint64

import (
	"regexp"
	"sort"
	"strings"
	"unicode"
	"unicode/utf8"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	"t73f.de/r/zsc/maps"
	"zettelstore.de/z/strfun"
	"zettelstore.de/z/zettel/id"
)

type keyUsage int

const (

package meta

import (
	"strings"
	"testing"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/zettel/id"
)

const testID = id.Zid(98765432101234)

func TestKeyIsValid(t *testing.T) {
	t.Parallel()

//-----------------------------------------------------------------------------

package meta

import (
	"strings"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	"t73f.de/r/zsc/maps"
	"zettelstore.de/z/strfun"
	"zettelstore.de/z/zettel/id"
)

// NewFromInput parses the meta data of a zettel.
func NewFromInput(zid id.Zid, inp *input.Input) *Meta {
	if inp.Ch == '-' && inp.PeekN(0) == '-' && inp.PeekN(1) == '-' {

package meta_test

import (
	"strings"
	"testing"

	"t73f.de/r/zsc/api"
	"t73f.de/r/zsc/input"
	"zettelstore.de/z/zettel/meta"
)

func parseMetaStr(src string) *meta.Meta {
	return meta.NewFromInput(testID, input.NewInput([]byte(src)))
}

import (
	"strconv"
	"strings"
	"sync"
	"time"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/zettel/id"
)

// DescriptionType is a description of a specific key type.
type DescriptionType struct {
	Name  string
	IsSet bool

//-----------------------------------------------------------------------------

package meta

import (
	"fmt"

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

// Supported syntax values.
const (
	SyntaxCSS      = api.ValueSyntaxCSS
	SyntaxDraw     = api.ValueSyntaxDraw
	SyntaxGif      = api.ValueSyntaxGif

package meta_test

import (
	"strings"
	"testing"

	"t73f.de/r/zsc/api"
	"zettelstore.de/z/zettel/id"
	"zettelstore.de/z/zettel/meta"
)

const testID = id.Zid(98765432101234)

func newMeta(title string, tags []string, syntax string) *meta.Meta {