package main

import (
	"log"
	"os"
	"strconv"
	"strings"
	"sync"
)

type telegramMessageCacheItem struct {
	Text   string
	Sender string
	Media  []string
}

func main() {
	log.Println("Go Chat Bridge запущен.")

	telegramToken := os.Getenv("TELEGRAM_TOKEN")
	discordToken := os.Getenv("DISCORD_TOKEN")

	if telegramToken == "" || discordToken == "" {
		log.Fatal("Необходимо задать переменные окружения TELEGRAM_TOKEN, DISCORD_TOKEN")
	}

	bridge, err := NewBridge(telegramToken, discordToken)
	if err != nil {
		log.Fatalf("Ошибка инициализации Bridge: %v", err)
	}

	log.Println("Bridge успешно инициализирован:", bridge)

	// Получаем ID чатов/каналов из переменных окружения
	telegramChatID := strings.TrimSpace(os.Getenv("TELEGRAM_CHAT_ID"))                      // int64
	discordChannelID := strings.TrimSpace(os.Getenv("DISCORD_CHANNEL_ID"))                  // string
	discordReactionChannelID := strings.TrimSpace(os.Getenv("DISCORD_REACTION_CHANNEL_ID")) // string
	telegramDuplicateReactionEmoji := strings.TrimSpace(os.Getenv("TELEGRAM_DUPLICATE_REACTION"))
	if telegramDuplicateReactionEmoji == "" {
		telegramDuplicateReactionEmoji = "✍️"
	}
	normalizedDuplicateReaction := normalizeEmoji(telegramDuplicateReactionEmoji)

	messageCache := make(map[string]telegramMessageCacheItem)
	var cacheMu sync.RWMutex

	cacheKey := func(chatID int64, messageID int) string {
		return strconv.FormatInt(chatID, 10) + ":" + strconv.Itoa(messageID)
	}

	sendTelegramMessageToDiscord := func(channelID, sender, text, msg string, media []string) error {
		if channelID == "" {
			return nil
		}
		if len(media) > 0 {
			files, derr := bridge.DownloadFiles(media)
			if derr == nil && len(files) > 0 {
				err := bridge.SendFilesToDiscord(channelID, files, "[TG] "+sender+": "+text)
				bridge.CleanupFiles(files)
				return err
			}
		}
		return bridge.SendToDiscord(channelID, "[TG] "+sender+": "+msg)
	}

	forward := func(text string, from string, sender string, media []string, messageID int, sourceChatID int64) {
		// Собираем итоговый текст с медиа URL, если есть
		msg := text
		if len(media) > 0 {
			if msg != "" {
				msg += "\n"
			}
			msg += strings.Join(media, "\n")
		}
		log.Printf("[Bridge] Пересылка сообщения от %s (%s): %s", from, sender, msg)

		switch from {
		case "telegram":
			// Для Discord отправляем файлы, если есть, иначе текст
			if err := sendTelegramMessageToDiscord(discordChannelID, sender, text, msg, media); err != nil {
				log.Printf("[Bridge] failed to send telegram message to main Discord channel: %v", err)
			}
			cacheMu.Lock()
			messageCache[cacheKey(sourceChatID, messageID)] = telegramMessageCacheItem{
				Text:   text,
				Sender: sender,
				Media:  append([]string(nil), media...),
			}
			cacheMu.Unlock()
		case "discord":
			// Для Telegram отправляем файлы, если есть, иначе текст
			if telegramChatID != "" {
				if id, err := strconv.ParseInt(telegramChatID, 10, 64); err == nil {
					if len(media) > 0 {
						files, derr := bridge.DownloadFiles(media)
						if derr == nil && len(files) > 0 {
							_ = bridge.SendFilesToTelegram(id, files, "[DS] "+sender+": "+text)
							bridge.CleanupFiles(files)
						} else {
							_ = bridge.SendToTelegram(id, "[DS] "+sender+": "+msg)
						}
					} else {
						_ = bridge.SendToTelegram(id, "[DS] "+sender+": "+msg)
					}
				}
			}
		}
	}

	bridge.StartTelegramListener(
		func(text string, sender string, media []string, messageID int, chatID int64) {
			forward(text, "telegram", sender, media, messageID, chatID)
		},
		func(chatID int64, messageID int, reaction string) {
			if discordChannelID != "" {
				_ = bridge.SendToDiscord(discordChannelID, "реакция поставлена")
			}

			if discordReactionChannelID == "" {
				log.Printf("[Bridge] reaction duplicate skipped: DISCORD_REACTION_CHANNEL_ID is empty")
				return
			}
			normalizedReaction := normalizeEmoji(reaction)
			if normalizedReaction != normalizedDuplicateReaction {
				log.Printf("[Bridge] reaction %q does not match configured %q", reaction, telegramDuplicateReactionEmoji)
				return
			}

			cacheMu.RLock()
			item, exists := messageCache[cacheKey(chatID, messageID)]
			cacheMu.RUnlock()
			if !exists {
				log.Printf("[Telegram] reaction %q for message %d in chat %d ignored: original message not in cache", reaction, messageID, chatID)
				return
			}

			msg := item.Text
			if len(item.Media) > 0 {
				if msg != "" {
					msg += "\n"
				}
				msg += strings.Join(item.Media, "\n")
			}
			if err := sendTelegramMessageToDiscord(discordReactionChannelID, item.Sender, item.Text, msg, item.Media); err != nil {
				log.Printf("[Bridge] failed to send duplicated message to reaction Discord channel: %v", err)
				return
			}
			log.Printf("[Bridge] duplicated message %d from chat %d to reaction channel by reaction %q", messageID, chatID, reaction)
		},
	)
	bridge.StartDiscordListener(discordChannelID, func(text string, sender string, media []string) {
		forward(text, "discord", sender, media, 0, 0)
	})

	log.Println("Chat Bridge запущен и работает")
	select {} // Бесконечный цикл для поддержания работы программы
}

func normalizeEmoji(value string) string {
	trimmed := strings.TrimSpace(value)
	filtered := strings.Map(func(r rune) rune {
		// Variation selectors and skin tone modifiers are optional in user input/reaction payloads.
		if r == '\uFE0E' || r == '\uFE0F' {
			return -1
		}
		if r >= '\U0001F3FB' && r <= '\U0001F3FF' {
			return -1
		}
		return r
	}, trimmed)
	return filtered
}