1 files changed, 253 insertions, 0 deletions
diff --git a/modules/templates/util_render.go b/modules/templates/util_render.go
new file mode 100644
index 00000000..c4c5376a
--- /dev/null
+++ b/modules/templates/util_render.go
@@ -0,0 +1,253 @@
+// Copyright 2023 The Gitea Authors. All rights reserved.
+// SPDX-License-Identifier: MIT
+
+package templates
+
+import (
+	"context"
+	"encoding/hex"
+	"fmt"
+	"html/template"
+	"math"
+	"net/url"
+	"regexp"
+	"strings"
+	"unicode"
+
+	issues_model "code.gitea.io/gitea/models/issues"
+	"code.gitea.io/gitea/modules/emoji"
+	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/markup"
+	"code.gitea.io/gitea/modules/markup/markdown"
+	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/translation"
+	"code.gitea.io/gitea/modules/util"
+)
+
+// RenderCommitMessage renders commit message with XSS-safe and special links.
+func RenderCommitMessage(ctx context.Context, msg string, metas map[string]string) template.HTML {
+	cleanMsg := template.HTMLEscapeString(msg)
+	// we can safely assume that it will not return any error, since there
+	// shouldn't be any special HTML.
+	fullMessage, err := markup.RenderCommitMessage(&markup.RenderContext{
+		Ctx:   ctx,
+		Metas: metas,
+	}, cleanMsg)
+	if err != nil {
+		log.Error("RenderCommitMessage: %v", err)
+		return ""
+	}
+	msgLines := strings.Split(strings.TrimSpace(fullMessage), "\n")
+	if len(msgLines) == 0 {
+		return template.HTML("")
+	}
+	return RenderCodeBlock(template.HTML(msgLines[0]))
+}
+
+// RenderCommitMessageLinkSubject renders commit message as a XSS-safe link to
+// the provided default url, handling for special links without email to links.
+func RenderCommitMessageLinkSubject(ctx context.Context, msg, urlDefault string, metas map[string]string) template.HTML {
+	msgLine := strings.TrimLeftFunc(msg, unicode.IsSpace)
+	lineEnd := strings.IndexByte(msgLine, '\n')
+	if lineEnd > 0 {
+		msgLine = msgLine[:lineEnd]
+	}
+	msgLine = strings.TrimRightFunc(msgLine, unicode.IsSpace)
+	if len(msgLine) == 0 {
+		return template.HTML("")
+	}
+
+	// we can safely assume that it will not return any error, since there
+	// shouldn't be any special HTML.
+	renderedMessage, err := markup.RenderCommitMessageSubject(&markup.RenderContext{
+		Ctx:         ctx,
+		DefaultLink: urlDefault,
+		Metas:       metas,
+	}, template.HTMLEscapeString(msgLine))
+	if err != nil {
+		log.Error("RenderCommitMessageSubject: %v", err)
+		return template.HTML("")
+	}
+	return RenderCodeBlock(template.HTML(renderedMessage))
+}
+
+// RenderCommitBody extracts the body of a commit message without its title.
+func RenderCommitBody(ctx context.Context, msg string, metas map[string]string) template.HTML {
+	msgLine := strings.TrimSpace(msg)
+	lineEnd := strings.IndexByte(msgLine, '\n')
+	if lineEnd > 0 {
+		msgLine = msgLine[lineEnd+1:]
+	} else {
+		return ""
+	}
+	msgLine = strings.TrimLeftFunc(msgLine, unicode.IsSpace)
+	if len(msgLine) == 0 {
+		return ""
+	}
+
+	renderedMessage, err := markup.RenderCommitMessage(&markup.RenderContext{
+		Ctx:   ctx,
+		Metas: metas,
+	}, template.HTMLEscapeString(msgLine))
+	if err != nil {
+		log.Error("RenderCommitMessage: %v", err)
+		return ""
+	}
+	return template.HTML(renderedMessage)
+}
+
+// Match text that is between back ticks.
+var codeMatcher = regexp.MustCompile("`([^`]+)`")
+
+// RenderCodeBlock renders "`…`" as highlighted "<code>" block, intended for issue and PR titles
+func RenderCodeBlock(htmlEscapedTextToRender template.HTML) template.HTML {
+	htmlWithCodeTags := codeMatcher.ReplaceAllString(string(htmlEscapedTextToRender), `<code class="inline-code-block">$1</code>`) // replace with HTML <code> tags
+	return template.HTML(htmlWithCodeTags)
+}
+
+const (
+	activeLabelOpacity   = uint8(255)
+	archivedLabelOpacity = uint8(127)
+)
+
+func GetLabelOpacityByte(isArchived bool) uint8 {
+	if isArchived {
+		return archivedLabelOpacity
+	}
+	return activeLabelOpacity
+}
+
+// RenderIssueTitle renders issue/pull title with defined post processors
+func RenderIssueTitle(ctx context.Context, text string, metas map[string]string) template.HTML {
+	renderedText, err := markup.RenderIssueTitle(&markup.RenderContext{
+		Ctx:   ctx,
+		Metas: metas,
+	}, template.HTMLEscapeString(text))
+	if err != nil {
+		log.Error("RenderIssueTitle: %v", err)
+		return template.HTML("")
+	}
+	return template.HTML(renderedText)
+}
+
+// RenderLabel renders a label
+// locale is needed due to an import cycle with our context providing the `Tr` function
+func RenderLabel(ctx context.Context, locale translation.Locale, label *issues_model.Label) template.HTML {
+	var (
+		archivedCSSClass string
+		textColor        = util.ContrastColor(label.Color)
+		labelScope       = label.ExclusiveScope()
+	)
+
+	description := emoji.ReplaceAliases(template.HTMLEscapeString(label.Description))
+
+	if label.IsArchived() {
+		archivedCSSClass = "archived-label"
+		description = locale.TrString("repo.issues.archived_label_description", description)
+	}
+
+	if labelScope == "" {
+		// Regular label
+
+		labelColor := label.Color + hex.EncodeToString([]byte{GetLabelOpacityByte(label.IsArchived())})
+		s := fmt.Sprintf("<div class='ui label %s' style='color: %s !important; background-color: %s !important;' data-tooltip-content title='%s'>%s</div>",
+			archivedCSSClass, textColor, labelColor, description, RenderEmoji(ctx, label.Name))
+		return template.HTML(s)
+	}
+
+	// Scoped label
+	scopeText := RenderEmoji(ctx, labelScope)
+	itemText := RenderEmoji(ctx, label.Name[len(labelScope)+1:])
+
+	// Make scope and item background colors slightly darker and lighter respectively.
+	// More contrast needed with higher luminance, empirically tweaked.
+	luminance := util.GetRelativeLuminance(label.Color)
+	contrast := 0.01 + luminance*0.03
+	// Ensure we add the same amount of contrast also near 0 and 1.
+	darken := contrast + math.Max(luminance+contrast-1.0, 0.0)
+	lighten := contrast + math.Max(contrast-luminance, 0.0)
+	// Compute factor to keep RGB values proportional.
+	darkenFactor := math.Max(luminance-darken, 0.0) / math.Max(luminance, 1.0/255.0)
+	lightenFactor := math.Min(luminance+lighten, 1.0) / math.Max(luminance, 1.0/255.0)
+
+	opacity := GetLabelOpacityByte(label.IsArchived())
+	r, g, b := util.HexToRBGColor(label.Color)
+	scopeBytes := []byte{
+		uint8(math.Min(math.Round(r*darkenFactor), 255)),
+		uint8(math.Min(math.Round(g*darkenFactor), 255)),
+		uint8(math.Min(math.Round(b*darkenFactor), 255)),
+		opacity,
+	}
+	itemBytes := []byte{
+		uint8(math.Min(math.Round(r*lightenFactor), 255)),
+		uint8(math.Min(math.Round(g*lightenFactor), 255)),
+		uint8(math.Min(math.Round(b*lightenFactor), 255)),
+		opacity,
+	}
+
+	scopeColor := "#" + hex.EncodeToString(scopeBytes)
+	itemColor := "#" + hex.EncodeToString(itemBytes)
+
+	s := fmt.Sprintf("<span class='ui label %s scope-parent' data-tooltip-content title='%s'>"+
+		"<div class='ui label scope-left' style='color: %s !important; background-color: %s !important'>%s</div>"+
+		"<div class='ui label scope-right' style='color: %s !important; background-color: %s !important'>%s</div>"+
+		"</span>",
+		archivedCSSClass, description,
+		textColor, scopeColor, scopeText,
+		textColor, itemColor, itemText)
+	return template.HTML(s)
+}
+
+// RenderEmoji renders html text with emoji post processors
+func RenderEmoji(ctx context.Context, text string) template.HTML {
+	renderedText, err := markup.RenderEmoji(&markup.RenderContext{Ctx: ctx},
+		template.HTMLEscapeString(text))
+	if err != nil {
+		log.Error("RenderEmoji: %v", err)
+		return template.HTML("")
+	}
+	return template.HTML(renderedText)
+}
+
+// ReactionToEmoji renders emoji for use in reactions
+func ReactionToEmoji(reaction string) template.HTML {
+	val := emoji.FromCode(reaction)
+	if val != nil {
+		return template.HTML(val.Emoji)
+	}
+	val = emoji.FromAlias(reaction)
+	if val != nil {
+		return template.HTML(val.Emoji)
+	}
+	return template.HTML(fmt.Sprintf(`<img alt=":%s:" src="%s/assets/img/emoji/%s.png"></img>`, reaction, setting.StaticURLPrefix, url.PathEscape(reaction)))
+}
+
+func RenderMarkdownToHtml(ctx context.Context, input string) template.HTML { //nolint:revive
+	output, err := markdown.RenderString(&markup.RenderContext{
+		Ctx:   ctx,
+		Metas: map[string]string{"mode": "document"},
+	}, input)
+	if err != nil {
+		log.Error("RenderString: %v", err)
+	}
+	return output
+}
+
+func RenderLabels(ctx context.Context, locale translation.Locale, labels []*issues_model.Label, repoLink string, isPull bool) template.HTML {
+	htmlCode := `<span class="labels-list">`
+	for _, label := range labels {
+		// Protect against nil value in labels - shouldn't happen but would cause a panic if so
+		if label == nil {
+			continue
+		}
+
+		issuesOrPull := "issues"
+		if isPull {
+			issuesOrPull = "pulls"
+		}
+		htmlCode += fmt.Sprintf("<a href='%s/%s?labels=%d'>%s</a> ",
+			repoLink, issuesOrPull, label.ID, RenderLabel(ctx, locale, label))
+	}
+	htmlCode += "</span>"
+	return template.HTML(htmlCode)
+}