// Fenrir console screen reader.
// Copyright (c) 2026 Storm Dragon
// SPDX-License-Identifier: GPL-3.0-or-later
//
// This program is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by the Free
// Software Foundation, either version 3 of the License, or (at your option)
// any later version.
//
// This program is distributed in the hope that it will be useful, but WITHOUT
// ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
// FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
// more details.
//
// You should have received a copy of the GNU General Public License along with
// this program. If not, see <https://www.gnu.org/licenses/gpl-3.0.html>.

package i18n

import (
	"os"
	"path/filepath"
	"strings"
	"testing"
)

func TestCatalogReusePluralRulesAndPythonFields(t *testing.T) {
	root := t.TempDir()
	dir := filepath.Join(root, "xx", "LC_MESSAGES")
	if err := os.MkdirAll(dir, 0700); err != nil {
		t.Fatal(err)
	}
	data := `msgid ""
msgstr ""
"Content-Type: text/plain; charset=UTF-8\n"
"Plural-Forms: nplurals=2; plural=(n != 1);\n"

msgid "Start Fenrir"
msgstr "translated-start"

msgid "screen {0}"
msgstr "translated-screen {0}"

msgid "line {0}, column {1}, Terminal {2}"
msgstr "{2}: {1}, {0}"

msgid "one item"
msgid_plural "many items"
msgstr[0] "translated-one"
msgstr[1] "translated-many"
`
	if err := os.WriteFile(filepath.Join(dir, "fenrir.po"), []byte(data), 0600); err != nil {
		t.Fatal(err)
	}
	previous := Use(New(root, "missing:xx_YY.UTF-8"))
	t.Cleanup(func() { Use(previous) })
	if got := T("Start Fenrir"); got != "translated-start" {
		t.Fatal("catalog not reused", got)
	}
	if got := Format("screen {0}", "3"); got != "translated-screen 3" {
		t.Fatal(got)
	}
	if got := Format("line {0}, column {1}, Terminal {2}", "7", "8", "9"); got != "9: 8, 7" {
		t.Fatal("translated field order lost", got)
	}
	if got := Format("screen {0}", "{0}"); got != "translated-screen {0}" {
		t.Fatal("replacement data was formatted again", got)
	}
	if got := N("one item", "many items", 1); got != "translated-one" {
		t.Fatal(got)
	}
	if got := N("one item", "many items", 3); got != "translated-many" {
		t.Fatal(got)
	}
	if got := T("start of screen"); got != "start of screen" {
		t.Fatal("missing translation lost English msgid", got)
	}
}

func TestLanguagePrecedenceAndCStopsFallback(t *testing.T) {
	for _, name := range []string{"LANGUAGE", "LC_ALL", "LC_MESSAGES", "LANG"} {
		t.Setenv(name, "")
	}
	if Language() != "C" {
		t.Fatal(Language())
	}
	for _, pair := range [][2]string{{"LANG", "en"}, {"LC_MESSAGES", "es"}, {"LC_ALL", "de"}, {"LANGUAGE", "pl:ru"}} {
		t.Setenv(pair[0], pair[1])
		if Language() != pair[1] {
			t.Fatal(Language())
		}
	}
	catalog := New(t.TempDir(), "C.UTF-8:de")
	if len(catalog.locales) != 0 {
		t.Fatal("C locale continued translation fallback")
	}
}

func TestInstalledFenrirCatalogWhenRequested(t *testing.T) {
	root := os.Getenv("FENRIR_TEST_LOCALE_DIR")
	if root == "" {
		t.Skip("set FENRIR_TEST_LOCALE_DIR to check an installed Fenrir catalog")
	}
	previous := Use(New(root, "de_DE.UTF-8"))
	t.Cleanup(func() { Use(previous) })
	if got := T("Start Fenrir"); got != "Fenrir starten" {
		t.Fatal("installed MO not reused", got)
	}
	if got := Format("screen {0}", "2"); got != "Bildschirm 2" {
		t.Fatal("Python fields not reused", got)
	}
}

func TestBundledCatalogsWithoutInstalledTranslations(t *testing.T) {
	root := t.TempDir()
	for _, trial := range []struct{ language, menu, tab string }{
		{"de_DE.UTF-8", "Fenrir-Menü", "Lesen Registerkarte"},
		{"es_ES.UTF-8", "Menú de Fenrir", "Lectura pestaña"},
		{"pl_PL.UTF-8", "Menu Fenrira", "Czytanie zakładka"},
		{"pt_BR.UTF-8", "Menu do Fenrir", "Leitura aba"},
		{"ru_RU.UTF-8", "Меню Fenrir", "Чтение, вкладка"},
	} {
		t.Run(trial.language, func(t *testing.T) {
			previous := Use(New(root, trial.language))
			t.Cleanup(func() { Use(previous) })
			if got := T("Fenrir Menu"); got != trial.menu {
				t.Fatalf("bundled menu: %q", got)
			}
			if got := Format("{0} tab", T("Reading")); got != trial.tab {
				t.Fatalf("nested translation: %q", got)
			}
			if got := Format("Added {0} to clipboard", "{0}: application text"); !strings.Contains(got, "{0}: application text") {
				t.Fatalf("application value reformatted: %q", got)
			}
			for _, message := range []string{"Start Fenrir", "character {0}", "number", "tab", "Could not check spelling: {0}"} {
				if T(message) == message {
					t.Errorf("untranslated %q", message)
				}
			}
		})
	}
}

func TestInstalledPriorityAndBundledLanguageFallback(t *testing.T) {
	root := t.TempDir()
	dir := filepath.Join(root, "de", "LC_MESSAGES")
	if err := os.MkdirAll(dir, 0700); err != nil {
		t.Fatal(err)
	}
	if err := os.WriteFile(filepath.Join(dir, "fenrir.po"), []byte("msgid \"Start Fenrir\"\nmsgstr \"custom-start\"\n"), 0600); err != nil {
		t.Fatal(err)
	}
	previous := Use(New(root, "missing:de:es"))
	t.Cleanup(func() { Use(previous) })
	if got := T("Start Fenrir"); got != "custom-start" {
		t.Fatal("installed translation lost priority", got)
	}
	if got := T("Fenrir Menu"); got != "Fenrir-Menü" {
		t.Fatal("later language replaced bundled German", got)
	}
	for _, language := range []string{"C.UTF-8:de", "POSIX:es", "en_US.UTF-8", "missing"} {
		Use(New(root, language))
		if got := T("Fenrir Menu"); got != "Fenrir Menu" {
			t.Fatalf("%s did not retain English: %q", language, got)
		}
	}
}