package main

import (
	"bufio"
	"context"
	"encoding/json"
	"flag"
	"fmt"
	"log"
	"net"
	"os"
	"os/signal"
	"path/filepath"
	"strings"
	"syscall"
	"time"

	"lel/internal/aiprocess"
	"lel/internal/clip"
	"lel/internal/config"
	"lel/internal/daemon"
	"lel/internal/inject"
	"lel/internal/ui"
	"lel/internal/x11"

	"github.com/BurntSushi/xgb/xproto"
	"github.com/getlantern/systray"
)

func main() {
	var configPath string
	var dryRun bool
	var noTray bool
	flag.StringVar(&configPath, "config", "", "path to config.json")
	flag.BoolVar(&dryRun, "dry-run", false, "register hotkey and log events without recording")
	flag.BoolVar(&noTray, "no-tray", false, "disable system tray icon")
	flag.Parse()

	logger := log.New(os.Stderr, "leld: ", log.LstdFlags)

	cfg, err := config.Load(configPath)
	if err != nil {
		logger.Fatalf("config error: %v", err)
	}

	if cfg.Streaming {
		logger.Printf("streaming mode is not supported; falling back to non-streaming")
	}

	runtimeDir := ensureRuntimeDir(logger)
	lockFile := filepath.Join(runtimeDir, "lel.lock")
	lock, err := lockSingleInstance(lockFile)
	if err != nil {
		logger.Fatalf("another instance is running (lock %s): %v", lockFile, err)
	}
	defer lock.Close()

	x, err := x11.New()
	if err != nil {
		logger.Fatalf("x11 connection failed: %v", err)
	}
	defer x.Close()

	mods, keycode, err := x.ParseHotkey(cfg.Hotkey)
	if err != nil {
		logger.Fatalf("hotkey parse failed: %v", err)
	}
	if err := x.GrabHotkey(mods, keycode); err != nil {
		logger.Fatalf("grab hotkey failed: %v", err)
	}
	defer x.UngrabHotkey(mods, keycode)

	backend, err := inject.NewBackend(cfg.InjectionBackend, inject.Deps{
		Clipboard: inject.ClipboardWriterFunc(clip.WriteClipboard),
		Paster:    inject.NewXdotoolPaster(nil),
		Typer:     inject.NewXdotoolTyper(nil),
	})
	if err != nil {
		logger.Fatalf("backend error: %v", err)
	}

	processor, err := aiprocess.New(aiprocess.Config{
		Enabled:          cfg.AIEnabled,
		Provider:         cfg.AIProvider,
		Model:            cfg.AIModel,
		Temperature:      cfg.AITemperature,
		SystemPromptFile: cfg.AISystemPromptFile,
		BaseURL:          cfg.AIBaseURL,
		APIKey:           cfg.AIAPIKey,
		TimeoutSec:       cfg.AITimeoutSec,
	})
	if err != nil {
		logger.Fatalf("ai processor error: %v", err)
	}

	d := daemon.New(cfg, x, logger, backend, processor)

	sockPath := filepath.Join(runtimeDir, "ctl.sock")
	if err := os.RemoveAll(sockPath); err != nil {
		logger.Fatalf("remove socket failed: %v", err)
	}
	ln, err := net.Listen("unix", sockPath)
	if err != nil {
		logger.Fatalf("listen socket failed: %v", err)
	}
	defer ln.Close()

	reloadPath := configPath
	if reloadPath == "" {
		reloadPath = config.DefaultPath()
	}
	go serveControl(logger, ln, d, &cfg, x, &mods, &keycode, reloadPath)

	logger.Printf("ready (hotkey: %s)", cfg.Hotkey)
	logConfig(logger, cfg, reloadPath)

	if noTray {
		go handleSignals(logger, d)
		runX11Loop(logger, x, d, mods, keycode, dryRun)
		return
	}

	onReady := func() {
		systray.SetTitle("lel")
		systray.SetTooltip("lel: idle")
		systray.SetIcon(ui.IconIdle())
		status := systray.AddMenuItem("Idle", "")
		status.Disable()
		systray.AddSeparator()
		quit := systray.AddMenuItem("Quit", "Quit lel")

		go func() {
			for st := range d.StateChanges() {
				switch st {
				case daemon.StateRecording:
					systray.SetIcon(ui.IconRecording())
					systray.SetTooltip("lel: recording")
					status.SetTitle("Recording")
				case daemon.StateTranscribing:
					systray.SetIcon(ui.IconTranscribing())
					systray.SetTooltip("lel: transcribing")
					status.SetTitle("Transcribing")
				case daemon.StateProcessing:
					systray.SetIcon(ui.IconProcessing())
					systray.SetTooltip("lel: ai processing")
					status.SetTitle("AI Processing")
				default:
					systray.SetIcon(ui.IconIdle())
					systray.SetTooltip("lel: idle")
					status.SetTitle("Idle")
				}
			}
		}()

		go func() {
			for range quit.ClickedCh {
				os.Exit(0)
			}
		}()

		go handleSignals(logger, d)
		go runX11Loop(logger, x, d, mods, keycode, dryRun)
	}

	systray.Run(onReady, func() {})
}

func logConfig(logger *log.Logger, cfg config.Config, path string) {
	safe := cfg
	safe.AIAPIKey = ""
	data, err := json.MarshalIndent(safe, "", "  ")
	if err != nil {
		logger.Printf("config: <error: %v>", err)
		return
	}
	logger.Printf("config (%s):\n%s", path, string(data))
}

func matchMods(state uint16, want uint16) bool {
	masked := state & ^uint16(xproto.ModMaskLock|xproto.ModMask2)
	return masked == want
}

func runX11Loop(logger *log.Logger, x *x11.Conn, d *daemon.Daemon, mods uint16, keycode xproto.Keycode, dryRun bool) {
	for {
		ev, err := x.X.WaitForEvent()
		if err != nil {
			logger.Printf("x11 event error: %v", err)
			continue
		}
		switch e := ev.(type) {
		case xproto.KeyPressEvent:
			if e.Detail == keycode && matchMods(e.State, mods) {
				if dryRun {
					logger.Printf("hotkey pressed (dry-run)")
					continue
				}
				d.Toggle()
			}
		}
	}
}

func handleSignals(logger *log.Logger, d *daemon.Daemon) {
	sigCh := make(chan os.Signal, 2)
	signal.Notify(sigCh, os.Interrupt, syscall.SIGTERM)
	sig := <-sigCh
	logger.Printf("signal received: %v, shutting down", sig)
	d.StopRecording("signal")
	ctx, cancel := context.WithTimeout(context.Background(), 5*time.Second)
	defer cancel()
	if !d.WaitForIdle(ctx) {
		logger.Printf("shutdown timeout, exiting")
	}
	os.Exit(0)
}

func ensureRuntimeDir(logger *log.Logger) string {
	dir := os.Getenv("XDG_RUNTIME_DIR")
	if dir == "" {
		dir = "/tmp"
	}
	dir = filepath.Join(dir, "lel")
	if err := os.MkdirAll(dir, 0o700); err != nil {
		logger.Fatalf("runtime dir error: %v", err)
	}
	return dir
}

func lockSingleInstance(path string) (*os.File, error) {
	f, err := os.OpenFile(path, os.O_CREATE|os.O_RDWR, 0o600)
	if err != nil {
		return nil, err
	}
	if err := syscall.Flock(int(f.Fd()), syscall.LOCK_EX|syscall.LOCK_NB); err != nil {
		_ = f.Close()
		return nil, err
	}
	return f, nil
}

func serveControl(logger *log.Logger, ln net.Listener, d *daemon.Daemon, cfg *config.Config, x *x11.Conn, mods *uint16, keycode *xproto.Keycode, configPath string) {
	for {
		conn, err := ln.Accept()
		if err != nil {
			logger.Printf("control accept error: %v", err)
			continue
		}
		go handleConn(logger, conn, d, cfg, x, mods, keycode, configPath)
	}
}

func handleConn(logger *log.Logger, conn net.Conn, d *daemon.Daemon, cfg *config.Config, x *x11.Conn, mods *uint16, keycode *xproto.Keycode, configPath string) {
	defer conn.Close()

	reader := bufio.NewReader(conn)
	line, _ := reader.ReadString('\n')
	line = strings.TrimSpace(line)

	switch line {
	case "status":
		_, _ = fmt.Fprintf(conn, "state=%s\n", d.State())
	case "stop":
		_, _ = fmt.Fprintf(conn, "stopping\n")
		logger.Printf("stop requested")
		os.Exit(0)
	case "reload":
		newCfg, err := config.Load(configPath)
		if err != nil {
			_, _ = fmt.Fprintf(conn, "reload error: %v\n", err)
			return
		}

		newMods, newKeycode, err := x.ParseHotkey(newCfg.Hotkey)
		if err != nil {
			_, _ = fmt.Fprintf(conn, "reload error: %v\n", err)
			return
		}

		x.UngrabHotkey(*mods, *keycode)
		if err := x.GrabHotkey(newMods, newKeycode); err != nil {
			_, _ = fmt.Fprintf(conn, "reload error: %v\n", err)
			return
		}

		backend, err := inject.NewBackend(newCfg.InjectionBackend, inject.Deps{
			Clipboard: inject.ClipboardWriterFunc(clip.WriteClipboard),
			Paster:    inject.NewXdotoolPaster(nil),
			Typer:     inject.NewXdotoolTyper(nil),
		})
		if err != nil {
			_, _ = fmt.Fprintf(conn, "reload error: %v\n", err)
			return
		}

		processor, err := aiprocess.New(aiprocess.Config{
			Enabled:          newCfg.AIEnabled,
			Provider:         newCfg.AIProvider,
			Model:            newCfg.AIModel,
			Temperature:      newCfg.AITemperature,
			SystemPromptFile: newCfg.AISystemPromptFile,
			BaseURL:          newCfg.AIBaseURL,
			APIKey:           newCfg.AIAPIKey,
			TimeoutSec:       newCfg.AITimeoutSec,
		})
		if err != nil {
			_, _ = fmt.Fprintf(conn, "reload error: %v\n", err)
			return
		}

		*mods = newMods
		*keycode = newKeycode
		*cfg = newCfg
		d.UpdateConfig(newCfg)
		d.UpdateBackend(backend)
		d.UpdateAI(processor)

		_, _ = fmt.Fprintf(conn, "reloaded\n")
	default:
		_, _ = fmt.Fprintf(conn, "unknown command\n")
	}
}