Support selecting theme on the footer (#35741)

Fixes: https://github.com/go-gitea/gitea/pull/27576

modules/setting/session.go

@@ -10,6 +10,7 @@ import (
 
 	"code.gitea.io/gitea/modules/json"
 	"code.gitea.io/gitea/modules/log"
+	"code.gitea.io/gitea/modules/util"
 )
 
 // SessionConfig defines Session settings
@@ -49,10 +50,8 @@ func loadSessionFrom(rootCfg ConfigProvider) {
 		checkOverlappedPath("[session].PROVIDER_CONFIG", SessionConfig.ProviderConfig)
 	}
 	SessionConfig.CookieName = sec.Key("COOKIE_NAME").MustString("i_like_gitea")
-	SessionConfig.CookiePath = AppSubURL
-	if SessionConfig.CookiePath == "" {
-		SessionConfig.CookiePath = "/"
-	}
+	// HINT: INSTALL-PAGE-COOKIE-INIT: the cookie system is not properly initialized on the Install page, so there is no CookiePath
+	SessionConfig.CookiePath = util.IfZero(AppSubURL, "/")
 	SessionConfig.Secure = sec.Key("COOKIE_SECURE").MustBool(strings.HasPrefix(strings.ToLower(AppURL), "https://"))
 	SessionConfig.Gclifetime = sec.Key("GC_INTERVAL_TIME").MustInt64(86400)
 	SessionConfig.Maxlifetime = sec.Key("SESSION_LIFE_TIME").MustInt64(86400)

modules/svg/svg.go

@@ -58,6 +58,9 @@ func MockIcon(icon string) func() {
 
 // RenderHTML renders icons - arguments icon name (string), size (int), class (string)
 func RenderHTML(icon string, others ...any) template.HTML {
+	if icon == "" {
+		return ""
+	}
 	size, class := gitea_html.ParseSizeAndClass(defaultSize, "", others...)
 	if svgStr, ok := svgIcons[icon]; ok {
 		// the code is somewhat hacky, but it just works, because the SVG contents are all normalized

modules/templates/helper.go

@@ -12,7 +12,6 @@ import (
 	"strings"
 	"time"
 
-	user_model "code.gitea.io/gitea/models/user"
 	"code.gitea.io/gitea/modules/base"
 	"code.gitea.io/gitea/modules/htmlutil"
 	"code.gitea.io/gitea/modules/markup"
@@ -21,7 +20,6 @@ import (
 	"code.gitea.io/gitea/modules/templates/eval"
 	"code.gitea.io/gitea/modules/util"
 	"code.gitea.io/gitea/services/gitdiff"
-	"code.gitea.io/gitea/services/webtheme"
 )
 
 // NewFuncMap returns functions for injecting to templates
@@ -130,7 +128,6 @@ func NewFuncMap() template.FuncMap {
 		"DisableWebhooks": func() bool {
 			return setting.DisableWebhooks
 		},
-		"UserThemeName": userThemeName,
 		"NotificationSettings": func() map[string]any {
 			return map[string]any{
 				"MinTimeout":            int(setting.UI.Notification.MinTimeout / time.Millisecond),
@@ -217,16 +214,6 @@ func evalTokens(tokens ...any) (any, error) {
 	return n.Value, err
 }
 
-func userThemeName(user *user_model.User) string {
-	if user == nil || user.Theme == "" {
-		return setting.UI.DefaultTheme
-	}
-	if webtheme.IsThemeAvailable(user.Theme) {
-		return user.Theme
-	}
-	return setting.UI.DefaultTheme
-}
-
 func isQueryParamEmpty(v any) bool {
 	return v == nil || v == false || v == 0 || v == int64(0) || v == ""
 }

modules/templates/util_render.go

@@ -23,8 +23,10 @@ import (
 	"code.gitea.io/gitea/modules/markup/markdown"
 	"code.gitea.io/gitea/modules/reqctx"
 	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/svg"
 	"code.gitea.io/gitea/modules/translation"
 	"code.gitea.io/gitea/modules/util"
+	"code.gitea.io/gitea/services/webtheme"
 )
 
 type RenderUtils struct {
@@ -259,3 +261,18 @@ func (ut *RenderUtils) RenderLabels(labels []*issues_model.Label, repoLink strin
 	htmlCode += "</span>"
 	return template.HTML(htmlCode)
 }
+
+func (ut *RenderUtils) RenderThemeItem(info *webtheme.ThemeMetaInfo, iconSize int) template.HTML {
+	svgName := "octicon-paintbrush"
+	switch info.ColorScheme {
+	case "dark":
+		svgName = "octicon-moon"
+	case "light":
+		svgName = "octicon-sun"
+	case "auto":
+		svgName = "gitea-eclipse"
+	}
+	icon := svg.RenderHTML(svgName, iconSize)
+	extraIcon := svg.RenderHTML(info.GetExtraIconName(), iconSize)
+	return htmlutil.HTMLFormat(`<div class="theme-menu-item" data-tooltip-content="%s">%s %s %s</div>`, info.GetDescription(), icon, info.DisplayName, extraIcon)
+}

modules/web/middleware/cookie.go

@@ -11,6 +11,7 @@ import (
 
 	"code.gitea.io/gitea/modules/session"
 	"code.gitea.io/gitea/modules/setting"
+	"code.gitea.io/gitea/modules/util"
 )
 
 // SetRedirectToCookie convenience function to set the RedirectTo cookie consistently
@@ -39,11 +40,13 @@ func SetSiteCookie(resp http.ResponseWriter, name, value string, maxAge int) {
 	// These are more specific than cookies without a trailing /, so
 	// we need to delete these if they exist.
 	deleteLegacySiteCookie(resp, name)
+
+	// HINT: INSTALL-PAGE-COOKIE-INIT: the cookie system is not properly initialized on the Install page, so there is no CookiePath
 	cookie := &http.Cookie{
 		Name:     name,
 		Value:    url.QueryEscape(value),
 		MaxAge:   maxAge,
-		Path:     setting.SessionConfig.CookiePath,
+		Path:     util.IfZero(setting.SessionConfig.CookiePath, "/"),
 		Domain:   setting.SessionConfig.Domain,
 		Secure:   setting.SessionConfig.Secure,
 		HttpOnly: true,