[I18N] Add Locale merger script

(cherry picked from commit ecc3dae2acaf567cd6b2888cc5c582588c7bfc53)
(cherry picked from commit c6c3fc6ace6b6aa4f4877c5a96da54899f2dc2fa)
(cherry picked from commit 4833bd594a49b70896c023b41da8a87ba33add0e)

[I18N] in the home page replace GitHub with Forgejo

The english string that shows on the home page to encourage for
contribution no longer reference GitHub. But some translations still
do. In this context, and this context only, replace it with Forgejo
even though it may not be correct in some cases.

Refs: https://codeberg.org/forgejo/forgejo/pulls/450
(cherry picked from commit 71de77f5ae59617eadda9e4992f1867a7acb7f17)
(cherry picked from commit e9adeae464287d71f0c444b555fc66b8682d588f)
(cherry picked from commit 6469290eac11a0c89fd748750407fc957a82dac5)

build/merge-forgejo-locales.go

@@ -0,0 +1,97 @@
+// Copyright 2022 The Forgejo Authors c/o Codeberg e.V.. All rights reserved.
+// Use of this source code is governed by a MIT-style
+// license that can be found in the LICENSE file.
+
+//go:build ignore
+
+package main
+
+import (
+	"bufio"
+	"os"
+	"regexp"
+	"strings"
+
+	"gopkg.in/ini.v1"
+)
+
+const (
+	trimPrefix   = "gitea_"
+	sourceFolder = "options/locales/"
+)
+
+// returns list of locales, still containing the file extension!
+func generate_locale_list() []string {
+	localeFiles, _ := os.ReadDir(sourceFolder)
+	locales := []string{}
+	for _, localeFile := range localeFiles {
+		if !localeFile.IsDir() && strings.HasPrefix(localeFile.Name(), trimPrefix) {
+			locales = append(locales, strings.TrimPrefix(localeFile.Name(), trimPrefix))
+		}
+	}
+	return locales
+}
+
+// replace all occurrences of Gitea with Forgejo
+func renameGiteaForgejo(filename string) []byte {
+	file, err := os.Open(filename)
+	if err != nil {
+		panic(err)
+	}
+
+	replacer := strings.NewReplacer(
+		"Gitea", "Forgejo",
+		"https://docs.gitea.io/en-us/install-from-binary/", "https://forgejo.org/download/#installation-from-binary",
+		"https://github.com/go-gitea/gitea/tree/master/docker", "https://forgejo.org/download/#container-image",
+		"https://docs.gitea.io/en-us/install-from-package/", "https://forgejo.org/download",
+		"https://code.gitea.io/gitea", "https://forgejo.org/download",
+		"code.gitea.io/gitea", "Forgejo",
+		`<a href="https://github.com/go-gitea/gitea/issues" target="_blank">GitHub</a>`, `<a href="https://codeberg.org/forgejo/forgejo/issues" target="_blank">Codeberg</a>`,
+		"https://github.com/go-gitea/gitea", "https://codeberg.org/forgejo/forgejo",
+		"https://blog.gitea.io", "https://forgejo.org/news",
+	)
+
+	out := make([]byte, 0, 1024)
+	scanner := bufio.NewScanner(file)
+	scanner.Split(bufio.ScanLines)
+	for scanner.Scan() {
+		line := scanner.Text()
+
+		if strings.HasPrefix(line, "license_desc=") {
+			line = strings.Replace(line, "GitHub", "Forgejo", 1)
+		}
+
+		if strings.HasPrefix(line, "[") && strings.HasSuffix(line, "]") {
+			out = append(out, []byte("\n"+line+"\n")...)
+		} else if strings.HasPrefix(line, "settings.web_hook_name_gitea") {
+			out = append(out, []byte("\n"+line+"\n")...)
+			out = append(out, []byte("settings.web_hook_name_forgejo = Forgejo\n")...)
+		} else if strings.HasPrefix(line, "migrate.gitea.description") {
+			re := regexp.MustCompile(`(.*Gitea)`)
+			out = append(out, []byte(re.ReplaceAllString(line, "${1}/Forgejo")+"\n")...)
+		} else {
+			out = append(out, []byte(replacer.Replace(line)+"\n")...)
+		}
+	}
+	file.Close()
+	return out
+}
+
+func main() {
+	locales := generate_locale_list()
+	var err error
+	var localeFile *ini.File
+	for _, locale := range locales {
+		giteaLocale := sourceFolder + "gitea_" + locale
+		localeFile, err = ini.LoadSources(ini.LoadOptions{
+			IgnoreInlineComment: true,
+		}, giteaLocale, renameGiteaForgejo(giteaLocale))
+		if err != nil {
+			panic(err)
+		}
+		err = localeFile.SaveTo("options/locale/locale_" + locale)
+		if err != nil {
+			panic(err)
+		}
+	}
+}