package main

import (
	"context"
	"flag"
	"fmt"
	"log/slog"
	"os"
	"os/exec"
	"os/signal"
	"strings"
	"syscall"
	"time"

	"github.com/bwmarrin/dgvoice"
	"github.com/bwmarrin/discordgo"
	"github.com/lmittmann/tint"
)

var (
	token    string
	radioURL = "https://atres-live.europafm.com/live/europafm/bitrate_1.m3u8"
	logger   *slog.Logger
	debug    bool
	guildID  string // For testing in a specific guild
)

func init() {
	flag.StringVar(&token, "token", "", "Discord Bot Token")
	flag.BoolVar(&debug, "debug", false, "Enable debug logging")
	flag.StringVar(&guildID, "guild", "", "Specific guild ID for command registration (leave empty for global commands)")
	flag.Parse()

	// Initialize logger with tint
	var logLevel slog.Level
	if debug {
		logLevel = slog.LevelDebug
	} else {
		logLevel = slog.LevelInfo
	}

	logger = slog.New(tint.NewHandler(os.Stderr, &tint.Options{
		Level:      logLevel,
		TimeFormat: time.RFC3339,
	}))
	slog.SetDefault(logger)
}

func main() {
	logger.Info("Starting EuropaFM Discord bot")

	if token == "" {
		token = os.Getenv("DISCORD_TOKEN")
		if token == "" {
			logger.Error("No token provided. Please provide it via -token flag or DISCORD_TOKEN environment variable")
			return
		}
	}

	// Check for guild-specific deployment from environment
	if guildID == "" {
		guildID = os.Getenv("GUILD_ID")
		if guildID != "" {
			logger.Info("Using guild-specific deployment from environment variable", "guild_id", guildID)
		}
	}

	// Create a new Discord session using the provided bot token
	dg, err := discordgo.New("Bot " + token)
	if err != nil {
		logger.Error("Error creating Discord session", "error", err)
		return
	}

	// Enable debug logging for DiscordGo if debug flag is set
	if debug {
		dg.LogLevel = discordgo.LogDebug
		dg.Debug = true
		logger.Debug("DiscordGo debug logging enabled")
	}

	// Register command handlers
	dg.AddHandler(func(s *discordgo.Session, i *discordgo.InteractionCreate) {
		logInteraction(s, i)

		if i.Type != discordgo.InteractionApplicationCommand {
			logger.Debug("Ignoring non-application command interaction",
				"type", i.Type,
				"guild_id", i.GuildID)
			return
		}

		cmdName := i.ApplicationCommandData().Name
		logger.Info("Received command interaction",
			"command", cmdName,
			"user", i.Member.User.Username,
			"guild_id", i.GuildID)

		switch cmdName {
		case "europafm":
			handleEuropaFMCommand(s, i)
		default:
			logger.Warn("Unknown command received", "command", cmdName)
		}
	})

	// Add handlers for checking interactions and commands
	dg.AddHandler(logRawInteraction)

	// Add a handler for connection events
	dg.AddHandler(func(s *discordgo.Session, r *discordgo.Ready) {
		logger.Info("Bot is ready",
			"username", r.User.Username,
			"discriminator", r.User.Discriminator,
			"id", r.User.ID,
			"session_id", r.SessionID)

		// Log guilds the bot is connected to
		logger.Info("Connected to guilds", "count", len(r.Guilds))
		for i, guild := range r.Guilds {
			if i < 10 { // Limit to 10 guilds in logs
				logger.Debug("Connected to guild", "name", guild.Name, "id", guild.ID)
			}
		}
	})

	// Set necessary intents
	dg.Identify.Intents = discordgo.IntentsGuilds | discordgo.IntentsGuildVoiceStates | discordgo.IntentsGuildMessages

	// Open a websocket connection to Discord
	logger.Info("Opening connection to Discord")
	err = dg.Open()
	if err != nil {
		logger.Error("Error opening connection", "error", err)
		return
	}

	// Get application info to verify bot identity
	app, err := dg.Application("@me")
	if err != nil {
		logger.Error("Error getting application info", "error", err)
	} else {
		logger.Info("Bot application info",
			"id", app.ID,
			"name", app.Name,
			"public", app.BotPublic,
			"require_code_grant", app.BotRequireCodeGrant)
	}

	// Register slash commands
	targetID := "" // For global commands
	if guildID != "" {
		// For guild-specific commands (faster updates during testing)
		targetID = guildID
		logger.Info("Registering commands for specific guild", "guild_id", guildID)
	} else {
		logger.Info("Registering global commands (may take up to an hour to propagate)")
	}

	// Check existing commands
	existingCmds, err := dg.ApplicationCommands(dg.State.User.ID, targetID)
	if err != nil {
		logger.Error("Error fetching existing commands", "error", err)
	} else {
		logger.Info("Found existing commands that will be deleted", "count", len(existingCmds))
		for _, cmd := range existingCmds {
			logger.Debug("Found existing command",
				"name", cmd.Name,
				"id", cmd.ID,
				"description", cmd.Description)

			// Delete existing command
			logger.Info("Deleting existing command", "name", cmd.Name, "id", cmd.ID)
			err := dg.ApplicationCommandDelete(dg.State.User.ID, targetID, cmd.ID)
			if err != nil {
				logger.Error("Error deleting command", "name", cmd.Name, "id", cmd.ID, "error", err)
			}
		}

		// Wait a bit for Discord to process the deletions
		logger.Info("Waiting for command deletions to process...")
		time.Sleep(2 * time.Second)
	}

	// Define the command
	cmd := &discordgo.ApplicationCommand{
		Name:        "europafm",
		Description: "Control EuropaFM radio streaming",
		Options: []*discordgo.ApplicationCommandOption{
			{
				Type:        discordgo.ApplicationCommandOptionSubCommand,
				Name:        "play",
				Description: "Start streaming EuropaFM radio in your voice channel",
			},
			{
				Type:        discordgo.ApplicationCommandOptionSubCommand,
				Name:        "stop",
				Description: "Stop streaming and leave the voice channel",
			},
		},
	}

	// Register the command
	registeredCmd, err := dg.ApplicationCommandCreate(dg.State.User.ID, targetID, cmd)
	if err != nil {
		logger.Error("Error creating slash command",
			"error", err,
			"command", cmd.Name,
			"details", err.Error())
	} else {
		logger.Info("Slash command registered successfully",
			"command", registeredCmd.Name,
			"id", registeredCmd.ID,
			"target_id", targetID)
	}

	// Verify registered commands
	time.Sleep(1 * time.Second) // Give Discord API a moment to catch up
	verifyCommands, err := dg.ApplicationCommands(dg.State.User.ID, targetID)
	if err != nil {
		logger.Error("Error fetching commands for verification", "error", err)
	} else {
		logger.Info("Verified registered commands", "count", len(verifyCommands))
		for _, cmd := range verifyCommands {
			logger.Debug("Verified command", "name", cmd.Name, "id", cmd.ID)
		}
	}

	// Wait for the signal to terminate
	logger.Info("Bot is now running. Press CTRL-C to exit.")
	sc := make(chan os.Signal, 1)
	signal.Notify(sc, syscall.SIGINT, syscall.SIGTERM, os.Interrupt)
	<-sc

	// Cleanup before exit
	logger.Info("Shutting down...")

	// Disconnect from all voice channels
	for _, vc := range dg.VoiceConnections {
		vc.Disconnect()
	}

	// Close the Discord session
	dg.Close()
	logger.Info("Shutdown complete")
}

// Log handler for raw interaction events
func logRawInteraction(s *discordgo.Session, e *discordgo.Event) {
	if !debug {
		return
	}

	if strings.HasPrefix(e.Type, "INTERACTION") {
		logger.Debug("Raw interaction event received",
			"type", e.Type,
			"operation", e.Operation)
	}
}

// Detailed logging for interactions
func logInteraction(s *discordgo.Session, i *discordgo.InteractionCreate) {
	if !debug {
		return
	}

	logger.Debug("Interaction details",
		"id", i.ID,
		"application_id", i.AppID,
		"type", i.Type,
		"token", i.Token[:5]+"...", // Log only first few chars of token for security
		"guild_id", i.GuildID,
		"channel_id", i.ChannelID,
		"member", i.Member != nil,
		"user", i.User != nil)
}

func handleEuropaFMCommand(s *discordgo.Session, i *discordgo.InteractionCreate) {
	ctx := context.Background()
	options := i.ApplicationCommandData().Options
	if len(options) == 0 {
		logger.Warn("Received europafm command with no subcommand", "interaction_id", i.ID)
		return
	}

	subCommand := options[0].Name
	logger := logger.With("subcommand", subCommand, "user", i.Member.User.Username, "guild_id", i.GuildID)
	logger.Info("Processing command")

	// Respond to the interaction
	err := s.InteractionRespond(i.Interaction, &discordgo.InteractionResponse{
		Type: discordgo.InteractionResponseChannelMessageWithSource,
		Data: &discordgo.InteractionResponseData{
			Content: "Processing your request...",
		},
	})

	if err != nil {
		logger.Error("Error responding to interaction", "error", err)
		return
	}

	switch subCommand {
	case "play":
		// Find the guild for that channel
		guildID := i.GuildID
		logger := logger.With("guild_id", guildID)

		// Find the voice channel the user is in
		vs, err := findUserVoiceState(ctx, s, guildID, i.Member.User.ID)
		if err != nil {
			logger.Warn("User not in voice channel", "error", err)
			followupMsg(s, i, "You need to be in a voice channel to use this command.")
			return
		}

		// Get channel details
		channel, err := s.Channel(vs.ChannelID)
		if err != nil {
			logger.Warn("Failed to get channel details", "channel_id", vs.ChannelID, "error", err)
		} else {
			logger = logger.With("channel_name", channel.Name, "channel_id", channel.ID)
		}

		// Connect to the voice channel
		logger.Info("Joining voice channel")
		vc, err := s.ChannelVoiceJoin(guildID, vs.ChannelID, false, true)
		if err != nil {
			logger.Error("Error joining voice channel", "error", err)
			followupMsg(s, i, "Error joining voice channel. Please try again.")
			return
		}

		// Wait for connection to be ready
		time.Sleep(2 * time.Second)

		// Update message
		followupMsg(s, i, "Now streaming EuropaFM radio in your voice channel!")

		// Start streaming - this is a blocking call, so we run it in a goroutine
		logger.Info("Starting audio stream")
		go func() {
			// Create a stop channel that's never closed for continuous streaming
			stopChan := make(chan bool)

			// Log when streaming ends (should only happen if there's an error)
			defer logger.Info("Audio streaming ended")

			// Start playing audio with enhanced error logging
			err := playAudioStream(vc, radioURL, stopChan, logger)

			if err != nil {
				logger.Error("Audio streaming error", "error", err)
				followupMsg(s, i, "The audio stream has ended unexpectedly. Please try again later.")
			}
		}()

	case "stop":
		// Find voice connection and disconnect
		vc, err := findExistingVoiceConnection(ctx, s, i.GuildID)
		if err != nil {
			logger.Info("No active voice connection found", "error", err)
			followupMsg(s, i, "Not currently streaming in any channel.")
			return
		}

		logger.Info("Disconnecting from voice channel")
		vc.Disconnect()
		followupMsg(s, i, "Disconnected from voice channel.")
	}
}

// Helper function to send followup messages
func followupMsg(s *discordgo.Session, i *discordgo.InteractionCreate, content string) {
	_, err := s.FollowupMessageCreate(i.Interaction, false, &discordgo.WebhookParams{
		Content: content,
	})
	if err != nil {
		logger.Error("Error sending followup message", "error", err, "content", content)
	}
}

func findUserVoiceState(ctx context.Context, s *discordgo.Session, guildID, userID string) (*discordgo.VoiceState, error) {
	guild, err := s.State.Guild(guildID)
	if err != nil {
		logger.Error("Error getting guild", "guild_id", guildID, "error", err)
		return nil, err
	}

	for _, vs := range guild.VoiceStates {
		if vs.UserID == userID {
			return vs, nil
		}
	}

	return nil, fmt.Errorf("user not in any voice channel")
}

func findExistingVoiceConnection(ctx context.Context, s *discordgo.Session, guildID string) (*discordgo.VoiceConnection, error) {
	for _, vc := range s.VoiceConnections {
		if vc.GuildID == guildID {
			return vc, nil
		}
	}
	return nil, fmt.Errorf("no active voice connection found")
}

func playAudioStream(vc *discordgo.VoiceConnection, url string, stopChan chan bool, logger *slog.Logger) error {
	logger.Info("Starting audio stream with enhanced logging", "url", url)

	// Set up panic recovery
	defer func() {
		if r := recover(); r != nil {
			logger.Error("Recovered from panic in audio stream", "panic", r)
		}
	}()

	// Try to detect what stream format we're dealing with
	if strings.HasSuffix(url, ".m3u8") {
		logger.Info("Detected HLS stream format (.m3u8)")
	} else if strings.HasSuffix(url, ".mp3") {
		logger.Info("Detected MP3 audio format")
	} else {
		logger.Info("Unknown stream format, attempting to play anyway")
	}

	// Before we start playing, make sure ffmpeg is available
	ffmpegPath, err := exec.LookPath("ffmpeg")
	if err != nil {
		logger.Error("ffmpeg not found in PATH", "error", err)
		return fmt.Errorf("ffmpeg not found: %w", err)
	}
	logger.Info("Found ffmpeg", "path", ffmpegPath)

	// Check ffmpeg version
	versionCmd := exec.Command(ffmpegPath, "-version")
	versionOutput, err := versionCmd.CombinedOutput()
	if err != nil {
		logger.Error("Failed to get ffmpeg version", "error", err)
	} else {
		versionLines := strings.Split(string(versionOutput), "\n")
		if len(versionLines) > 0 {
			logger.Info("ffmpeg version", "version", versionLines[0])
		}
	}

	// Try to run a test of ffmpeg with the URL to see if it can connect
	testCmd := exec.Command(ffmpegPath, "-i", url, "-t", "1", "-f", "null", "-")
	logger.Info("Testing stream with ffmpeg", "command", testCmd.String())
	testOutput, err := testCmd.CombinedOutput()
	if err != nil {
		logger.Warn("ffmpeg test returned error but this might be normal", "error", err, "output", string(testOutput))
		// Continue anyway - some errors are normal here
	} else {
		logger.Info("ffmpeg test succeeded", "output", string(testOutput))
	}

	// Set up a context with timeout for the stream
	ctx, cancel := context.WithCancel(context.Background())
	defer cancel()

	// Start a goroutine to monitor the stream
	go func() {
		select {
		case <-ctx.Done():
			// Context was canceled, nothing to do
			return
		case <-time.After(5 * time.Second):
			// If we're still running after 5 seconds, assume the stream is working
			logger.Info("Stream appears to be working")
		}
	}()

	// Start the stream
	logger.Info("Starting audio stream with dgvoice", "url", url)
	dgvoice.PlayAudioFile(vc, url, stopChan)

	// If we get here, the stream ended unexpectedly
	logger.Warn("Audio stream ended unexpectedly")

	return fmt.Errorf("audio stream ended unexpectedly")
}