package notifier

import (
	"log"
	"sync"

	"git.pengzhan.dev/aimaren/internal/config"

	tgbotapi "github.com/go-telegram-bot-api/telegram-bot-api/v5"
)

// TelegramNotifier no longer needs to store chat IDs.
type TelegramNotifier struct {
	bot *tgbotapi.BotAPI
}

// NewTelegramNotifier is now simpler and only requires the token.
func NewTelegramNotifier(cfg config.Config) (*TelegramNotifier, error) {
	bot, err := tgbotapi.NewBotAPI(cfg.Telegram.Token)
	if err != nil {
		return nil, err
	}
	return &TelegramNotifier{bot: bot}, nil
}

// Broadcast sends a message to all provided chat IDs in parallel.
func (t *TelegramNotifier) Broadcast(chatIDs []int64, message string) error {
	var wg sync.WaitGroup

	for _, id := range chatIDs {
		wg.Add(1)
		// Launch a goroutine for each message to send them concurrently.
		go func(chatID int64) {
			defer wg.Done()
			msg := tgbotapi.NewMessage(chatID, message)
			if _, err := t.bot.Send(msg); err != nil {
				log.Printf("⚠️ Failed to send Telegram notification to chat ID %d: %v", chatID, err)
			}
		}(id)
	}

	// Wait for all messages to be sent before returning.
	wg.Wait()
	return nil
}

// SendTo sends a message to a single, specific chat ID.
// This is used by the bot-server for welcome messages.
func (t *TelegramNotifier) SendTo(chatID int64, message string) error {
	msg := tgbotapi.NewMessage(chatID, message)
	_, err := t.bot.Send(msg)
	return err
}
