Initial commit

Assisted-by: GLM 5.3

internal/admin/render.go

@@ -0,0 +1,244 @@
+// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
+// SPDX-License-Identifier: PolyForm-Noncommercial-1.0.0
+
+// Package admin serves the server-rendered admin UI: authentication,
+// post management, settings, and the media library.
+package admin
+
+import (
+	"bytes"
+	"context"
+	"encoding/json/v2"
+	"fmt"
+	"html/template"
+	"io"
+	"strings"
+	"sync"
+
+	"sourcedock.dev/petrbalvin/volumen/internal/config"
+	"sourcedock.dev/petrbalvin/volumen/internal/diff"
+	"sourcedock.dev/petrbalvin/volumen/internal/i18n"
+	"sourcedock.dev/petrbalvin/volumen/internal/users"
+	"sourcedock.dev/petrbalvin/volumen/internal/web"
+)
+
+// Crumb is one breadcrumb entry. UI marks a fixed interface label the
+// renderer translates; content labels (post titles) pass through.
+type Crumb struct {
+	Label  string
+	Href   string
+	IsLast bool
+	UI     bool
+}
+
+// PageData is the template context shared by every admin page; page
+// handlers fill the specific fields they need.
+type PageData struct {
+	Config          *config.Config
+	Path            string
+	CSPNonce        string
+	Version         string
+	UpdateAvailable string
+
+	// Lang is the interface language this request renders in ("en" or
+	// "cs"), resolved from the account, the language cookie, or the
+	// site language. It feeds the html lang attribute, which the date
+	// picker and the relative-time formatter read.
+	Lang string
+
+	// Theme is the colour scheme this request renders in, resolved
+	// from the account, the theme cookie, or the default. It feeds the
+	// html data-theme attribute the stylesheet's scheme blocks read.
+	Theme string
+
+	CurrentUser       string
+	CurrentRole       string
+	CurrentUserRecord *users.User
+	UsersExist        bool
+	CSRFToken         string
+
+	IsLogin         bool
+	IsSetup         bool
+	IsAuthenticated bool
+
+	// SetupI18n carries the wizard's strings in every shipped
+	// language, so the language chips can swap the page text without
+	// a reload and without losing what the operator typed.
+	SetupI18n   template.JS
+	DisplayName string
+	UserPhoto   string
+	UserInitial string
+
+	Crumbs     []Crumb
+	Error      string
+	RetryAfter int
+	Notice     string
+
+	// Dashboard.
+	Posts     []postCard
+	Stats     dashboardStats
+	TagCounts []tagCount
+	Q         string
+
+	// Editor and history.
+	IsNew             bool
+	IsEdit            bool
+	Post              *editorPost
+	PostTemplates     []tplOption
+	TemplatesJSON     template.JS
+	Restored          bool
+	Duplicated        bool
+	AuthorPlaceholder string
+	PreviewToken      string
+	Slug              string
+	Heading           string
+	Revisions         []revisionRow
+	DiffChunks        []diff.Chunk
+	DiffName          string
+	DiffWhen          string
+
+	// Settings.
+	IsAdmin           bool
+	Roles             []string
+	DefaultRole       string
+	UserRows          []userRow
+	TemplatesList     []tplOption
+	WebhookRows       []hookRow
+	WebhookDeliveries []deliveryRow
+	TokenRows         []tokenRow
+	NewToken          string
+	MediaItems        []mediaRow
+
+	// The second factor: its state on the account, an enrolment in
+	// flight, and the one-time recovery codes a change just produced.
+	TotpEnabled    bool
+	TotpPending    bool
+	TotpSVG        template.HTML
+	TotpSecret     string
+	TotpURI        string
+	RecoveryCodes  []string
+	RecoveryNotice string
+	MediaTotal     string
+	Target         string
+
+	// Sidebar navigation highlighting.
+	NavPosts    bool
+	NavNew      bool
+	NavImport   bool
+	NavMedia    bool
+	NavSettings bool
+}
+
+// Tr translates a simple message in this request's language. Handlers
+// use it for the strings they compose in Go; templates use the tr and
+// trn funcs, which read the same catalogue.
+func (d *PageData) Tr(s string) string {
+	return i18n.Admin.T(d.Lang, s)
+}
+
+// Trf translates a simple message with one value.
+func (d *PageData) Trf(s, arg string) string {
+	return i18n.Admin.Tf(d.Lang, s, arg)
+}
+
+// langRenderer is one language's parsed template set. The translation
+// funcs close over the language, so a page renders whole in one tongue
+// with no per-string lookups in the handlers.
+type langRenderer struct {
+	pages map[string]*template.Template
+}
+
+// Renderer executes the embedded admin templates in every shipped
+// language.
+type Renderer struct {
+	mu    sync.Mutex
+	langs map[string]*langRenderer
+}
+
+// NewRenderer parses the layout together with every page template, one
+// set per shipped language.
+func NewRenderer() (*Renderer, error) {
+	fs := web.TemplateFS()
+	r := &Renderer{langs: map[string]*langRenderer{}}
+	for _, lang := range i18n.Languages {
+		base, err := template.New("layout.html").Funcs(funcMap(lang)).ParseFS(fs, "templates/layout.html")
+		if err != nil {
+			return nil, fmt.Errorf("parse layout (%s): %w", lang, err)
+		}
+		lr := &langRenderer{pages: map[string]*template.Template{}}
+		for _, page := range pageNames() {
+			clone, err := base.Clone()
+			if err != nil {
+				return nil, fmt.Errorf("clone layout for %s (%s): %w", page, lang, err)
+			}
+			if _, err := clone.ParseFS(fs, "templates/"+page); err != nil {
+				return nil, fmt.Errorf("parse %s (%s): %w", page, lang, err)
+			}
+			lr.pages[page] = clone
+		}
+		r.langs[lang] = lr
+	}
+	return r, nil
+}
+
+// pageNames lists the page templates parsed alongside the layout.
+func pageNames() []string {
+	return []string{
+		"login.html", "setup.html", "twofactor.html", "list.html", "form.html", "history.html", "diff.html",
+		"import.html",
+		"settings.html", "media.html", "update.html", "notfound.html",
+	}
+}
+
+// Render executes the named page inside the layout shell, in the
+// language the page data carries. The context is the request's, so a
+// template failure is logged against it.
+func (r *Renderer) Render(ctx context.Context, w io.Writer, page string, data *PageData) error {
+	lang := data.Lang
+	if !i18n.Valid(lang) {
+		lang = "en"
+	}
+	// Fixed breadcrumb labels are interface strings; content labels
+	// (a post title) pass through untouched.
+	for i, c := range data.Crumbs {
+		if c.UI {
+			data.Crumbs[i].Label = i18n.Admin.T(lang, c.Label)
+		}
+	}
+	r.mu.Lock()
+	lr := r.langs[lang]
+	r.mu.Unlock()
+	tmpl, ok := lr.pages[page]
+	if !ok {
+		return fmt.Errorf("unknown admin page %q", page)
+	}
+	var buf bytes.Buffer
+	if err := tmpl.ExecuteTemplate(&buf, "layout", data); err != nil {
+		web.Logger(ctx).Warn("admin: template error", "page", page, "error", err)
+		return err
+	}
+	_, err := w.Write(buf.Bytes())
+	return err
+}
+
+func funcMap(lang string) template.FuncMap {
+	cat := i18n.Admin
+	return template.FuncMap{
+		"lower": strings.ToLower,
+		"join":  func(items []string, sep string) string { return strings.Join(items, sep) },
+		"tr":    func(s string) string { return cat.T(lang, s) },
+		"trh":   func(s string) template.HTML { return template.HTML(cat.TH(lang, s)) },
+		"trf":   func(s, arg string) string { return cat.Tf(lang, s, arg) },
+		"trn":   func(n int, id string) string { return cat.N(lang, id, n) },
+		"i18nJSON": func() template.JS {
+			b, err := json.Marshal(cat.JS(lang))
+			if err != nil {
+				return "{}"
+			}
+			// The catalogue holds authored strings only, but the same
+			// script-embedding rule as templatesJSON applies: no literal
+			// "<" may reach the page inside a script element.
+			return template.JS(strings.ReplaceAll(string(b), "<", `\u003c`))
+		},
+	}
+}