// Copyright (c) 2026 Storm Dragon
// SPDX-License-Identifier: GPL-3.0-or-later

package app

import (
	"context"
	"os"
	"path/filepath"
	"strings"
	"testing"
	"time"

	"git.stormux.org/storm/fenrir/internal/command"
	"git.stormux.org/storm/fenrir/internal/config"
	"git.stormux.org/storm/fenrir/internal/datetime"
	"git.stormux.org/storm/fenrir/internal/input"
	"git.stormux.org/storm/fenrir/internal/interaction"
	"git.stormux.org/storm/fenrir/internal/screen"
)

func TestTimeDateMenuAppliesOnlyAfterSave(t *testing.T) {
	for _, action := range []string{"save", "cancel", "failed save"} {
		t.Run(action, func(t *testing.T) {
			path := filepath.Join(t.TempDir(), "settings.toml")
			// Put this group first to exercise its controls directly.
			original := "version=3\n[presentation.time_and_date]\ntime_format='24-hour-seconds'\ndate_format='numbers-ymd'\n"
			if err := os.WriteFile(path, []byte(original), 0600); err != nil {
				t.Fatal(err)
			}
			settings, err := config.Decode([]byte(original))
			if err != nil {
				t.Fatal(err)
			}
			source := &fakeSource{snapshot: screen.Snapshot{Terminal: 1, Active: true}}
			keys, voice := &fakeKeys{events: make(chan error, 4)}, &fakeVoice{}
			keys.onCapture = func(enabled bool) {
				if !enabled {
					keys.events <- nil
				}
			}
			voice.onSay = func(text string) {
				if strings.HasPrefix(text, "Fenrir Menu.") || strings.HasPrefix(text, "Could not save settings:") {
					keys.events <- nil
				}
			}
			step := 0
			keys.poll = func(_ bool, handle func(input.Decision)) error {
				step++
				key := func(name string, shift bool) { handle(input.Decision{UI: &interaction.Key{Name: name, Shift: shift}}) }
				switch step {
				case 1:
					handle(input.Decision{Command: command.FenrirMenu})
				case 2:
					key("tab", false)
					key("down", false) // 24-hour-seconds -> 24-hour-seconds-words.
					key("tab", false)
					key("down", false) // numbers-ymd -> full-dm.
					if action == "cancel" {
						key("escape", false)
						break
					}
					if action == "failed save" {
						if err := os.WriteFile(path, []byte(original+"# external edit\n"), 0600); err != nil {
							t.Fatal(err)
						}
					}
					for range 4 {
						key("tab", true)
					}
					key("enter", false)
				case 3:
					if action == "failed save" {
						key("escape", false)
					}
					formats := settings.Presentation.DateTime
					if action == "save" {
						formats.TimeFormat, formats.DateFormat = "24-hour-seconds-words", "full-dm"
					}
					for _, id := range []command.ID{command.Time, command.Date} {
						format, value := datetime.Format_time, formats.TimeFormat
						if id == command.Date {
							format, value = datetime.Format_date, formats.DateFormat
						}
						before, _ := format(value, time.Now())
						handle(input.Decision{Command: id, Interrupt: true})
						after, _ := format(value, time.Now())
						got := voice.messages[len(voice.messages)-1]
						if got != before && got != after {
							t.Fatal("running format", id, got, before, after)
						}
					}
					handle(input.Decision{Command: command.Quit})
				}
				return nil
			}
			ctx, cancel := context.WithTimeout(context.Background(), 2*time.Second)
			defer cancel()
			if err := run(ctx, source, keys, voice, nil, RunOptions{Settings: settings, ConfigPath: path}); err != nil || step != 3 {
				t.Fatal(err, step, voice.messages)
			}
			loaded, _, err := config.Load(path, nil)
			want := settings.Presentation.DateTime
			if action == "save" {
				want.TimeFormat, want.DateFormat = "24-hour-seconds-words", "full-dm"
			}
			if err != nil || loaded.Presentation.DateTime != want {
				t.Fatal("saved formats", loaded.Presentation.DateTime, err)
			}
		})
	}
}