// tefter-desktop — Wails v2 shell around the shared frontend bundle.
// Window + tray + global shortcut + single-instance lock; all app logic
// (storage, sync) lives in the frontend, so it works fully offline.
package main

import (
	"context"
	"embed"
	"flag"
	"log"
	"os"
	"strings"

	"github.com/wailsapp/wails/v2"
	"github.com/wailsapp/wails/v2/pkg/options"
	"github.com/wailsapp/wails/v2/pkg/options/assetserver"
	"github.com/wailsapp/wails/v2/pkg/options/mac"
	wruntime "github.com/wailsapp/wails/v2/pkg/runtime"

	"fyne.io/systray"
	"golang.design/x/hotkey"
)

// Version is stamped via -ldflags "-X main.Version=…".
var Version = "dev"

//go:embed all:frontend/dist
var assets embed.FS

//go:embed build/appicon.png
var trayIcon []byte

type appShell struct {
	ctx         context.Context
	quitOnClose bool
	hotkeyCombo string
	endTray     func()
	quitting    bool
}

func main() {
	quitOnClose := flag.Bool("quit-on-close", envBool("TEFTER_QUIT_ON_CLOSE"), "quit when the window closes instead of hiding to tray")
	combo := flag.String("hotkey", envOr("TEFTER_HOTKEY", "ctrl+shift+space"), "global show/hide shortcut, e.g. ctrl+shift+space")
	flag.Parse()

	s := &appShell{quitOnClose: *quitOnClose, hotkeyCombo: *combo}

	err := wails.Run(&options.App{
		Title:  "Tefter",
		Width:  980,
		Height: 700,
		AssetServer: &assetserver.Options{
			Assets: assets,
		},
		HideWindowOnClose: !*quitOnClose,
		OnStartup:         s.startup,
		OnShutdown:        s.shutdown,
		SingleInstanceLock: &options.SingleInstanceLock{
			UniqueId:               "life.uka.tefter",
			OnSecondInstanceLaunch: s.onSecondInstance,
		},
		Mac: &mac.Options{
			About: &mac.AboutInfo{
				Title:   "Tefter " + Version,
				Message: "Self-hosted Notational Velocity style notes",
			},
		},
	})
	if err != nil {
		log.Fatal(err)
	}
}

func (s *appShell) startup(ctx context.Context) {
	s.ctx = ctx

	// Tray: open, sync now, quit (SPEC §7). RunWithExternalLoop coexists with
	// the Wails main loop.
	start, end := systray.RunWithExternalLoop(s.trayReady, nil)
	s.endTray = end
	start()

	// Global show/hide shortcut. Best effort: requires X11 on Linux.
	go s.registerHotkey()
}

func (s *appShell) shutdown(ctx context.Context) {
	if s.endTray != nil {
		s.endTray()
	}
}

func (s *appShell) onSecondInstance(data options.SecondInstanceData) {
	s.showAndFocus()
}

func (s *appShell) trayReady() {
	systray.SetIcon(trayIcon)
	systray.SetTitle("Tefter")
	systray.SetTooltip("Tefter — notes")
	mOpen := systray.AddMenuItem("Open", "Show the Tefter window")
	mSync := systray.AddMenuItem("Sync now", "Trigger a sync")
	systray.AddSeparator()
	mQuit := systray.AddMenuItem("Quit", "Quit Tefter")
	go func() {
		for {
			select {
			case <-mOpen.ClickedCh:
				s.showAndFocus()
			case <-mSync.ClickedCh:
				wruntime.EventsEmit(s.ctx, "tefter:sync")
			case <-mQuit.ClickedCh:
				s.quitting = true
				wruntime.Quit(s.ctx)
				return
			}
		}
	}()
}

func (s *appShell) registerHotkey() {
	mods, key, ok := parseHotkey(s.hotkeyCombo)
	if !ok {
		log.Printf("hotkey: cannot parse %q, global shortcut disabled", s.hotkeyCombo)
		return
	}
	hk := hotkey.New(mods, key)
	if err := hk.Register(); err != nil {
		log.Printf("hotkey: register %q: %v (global shortcut disabled)", s.hotkeyCombo, err)
		return
	}
	log.Printf("hotkey: %s toggles the window", s.hotkeyCombo)
	for range hk.Keydown() {
		s.showAndFocus()
	}
}

func (s *appShell) showAndFocus() {
	wruntime.WindowShow(s.ctx)
	// The classic NV "always at hand" flow: land in the omnibar.
	wruntime.EventsEmit(s.ctx, "tefter:focus-omnibar")
}

func envOr(k, def string) string {
	if v := os.Getenv(k); v != "" {
		return v
	}
	return def
}

func envBool(k string) bool {
	v := strings.ToLower(os.Getenv(k))
	return v == "1" || v == "true" || v == "yes"
}

// parseHotkey turns "ctrl+shift+space" into golang.design/x/hotkey values.
// modAlt/modCmd are defined per-OS in hotkey_*.go.
func parseHotkey(combo string) ([]hotkey.Modifier, hotkey.Key, bool) {
	var mods []hotkey.Modifier
	var key hotkey.Key
	haveKey := false
	for _, part := range strings.Split(strings.ToLower(combo), "+") {
		switch p := strings.TrimSpace(part); p {
		case "ctrl", "control":
			mods = append(mods, hotkey.ModCtrl)
		case "shift":
			mods = append(mods, hotkey.ModShift)
		case "alt", "option":
			mods = append(mods, modAlt)
		case "cmd", "meta", "super", "win":
			mods = append(mods, modCmd)
		case "space":
			key, haveKey = hotkey.KeySpace, true
		default:
			if len(p) == 1 {
				if k, found := charKeys[rune(p[0])]; found {
					key, haveKey = k, true
				}
			}
		}
	}
	return mods, key, haveKey
}

var charKeys = map[rune]hotkey.Key{
	'a': hotkey.KeyA, 'b': hotkey.KeyB, 'c': hotkey.KeyC, 'd': hotkey.KeyD,
	'e': hotkey.KeyE, 'f': hotkey.KeyF, 'g': hotkey.KeyG, 'h': hotkey.KeyH,
	'i': hotkey.KeyI, 'j': hotkey.KeyJ, 'k': hotkey.KeyK, 'l': hotkey.KeyL,
	'm': hotkey.KeyM, 'n': hotkey.KeyN, 'o': hotkey.KeyO, 'p': hotkey.KeyP,
	'q': hotkey.KeyQ, 'r': hotkey.KeyR, 's': hotkey.KeyS, 't': hotkey.KeyT,
	'u': hotkey.KeyU, 'v': hotkey.KeyV, 'w': hotkey.KeyW, 'x': hotkey.KeyX,
	'y': hotkey.KeyY, 'z': hotkey.KeyZ,
	'0': hotkey.Key0, '1': hotkey.Key1, '2': hotkey.Key2, '3': hotkey.Key3,
	'4': hotkey.Key4, '5': hotkey.Key5, '6': hotkey.Key6, '7': hotkey.Key7,
	'8': hotkey.Key8, '9': hotkey.Key9,
}