package bot

import (
	"context"
	"fmt"
	"log"
	"strings"
	"time"

	"ops-assistant/internal/core/ops"
	"ops-assistant/models"

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

// DefaultUserID 统一用户ID
const DefaultUserID int64 = 1

type TGBot struct {
	api    *tgbotapi.BotAPI
	db     *gorm.DB
	opsSvc *ops.Service
}

func NewTGBot(db *gorm.DB, token string, opsSvc *ops.Service) (*TGBot, error) {
	bot, err := tgbotapi.NewBotAPI(token)
	if err != nil {
		return nil, err
	}
	return &TGBot{api: bot, db: db, opsSvc: opsSvc}, nil
}

func (b *TGBot) Start(ctx context.Context) {
	u := tgbotapi.NewUpdate(0)
	u.Timeout = 60
	updates := b.api.GetUpdatesChan(u)

	log.Println("🚀 Telegram Bot 已启动")

	for {
		select {
		case <-ctx.Done():
			log.Println("⏳ Telegram Bot 正在停止...")
			b.api.StopReceivingUpdates()
			return
		case update, ok := <-updates:
			if !ok {
				return
			}
			if update.Message == nil || update.Message.Text == "" {
				continue
			}

			eventID := fmt.Sprintf("tg:%d", update.UpdateID)
			if b.isDuplicate(eventID) {
				continue
			}
			log.Printf("📩 inbound platform=telegram event=%s chat=%d user=%d text=%q", eventID, update.Message.Chat.ID, update.Message.From.ID, strings.TrimSpace(update.Message.Text))
			b.handleMessage(update.Message)
		}
	}
}

func (b *TGBot) isDuplicate(eventID string) bool {
	if b.db == nil || strings.TrimSpace(eventID) == "" {
		return false
	}
	var existed models.MessageDedup
	if err := b.db.Where("platform = ? AND event_id = ?", "telegram", eventID).First(&existed).Error; err == nil {
		return true
	}
	_ = b.db.Create(&models.MessageDedup{Platform: "telegram", EventID: eventID, ProcessedAt: time.Now()}).Error
	return false
}

func (b *TGBot) handleMessage(msg *tgbotapi.Message) {
	text := msg.Text
	chatID := msg.Chat.ID

	if b.opsSvc != nil {
		if handled, out := b.opsSvc.Handle(DefaultUserID, text); handled {
			m := tgbotapi.NewMessage(chatID, out)
			if _, err := b.api.Send(m); err != nil {
				log.Printf("发送OPS消息失败 chat=%d: %v", chatID, err)
			}
			return
		}
	}

	reply := ""
	switch text {
	case "/start":
		reply = "🛠️ 欢迎使用 Ops-Assistant！\n\n模块化运维命令助手，支持：\n• /cpa - CPA 管理\n• /cf - Cloudflare 管理\n• /cfdav - cfdav 管理\n• /sub - 订阅管理\n• /mail - 邮箱管理\n\n/help - 使用说明"
	case "/help":
		reply = "📖 使用说明：\n\n直接发送 OPS 命令即可，例如：\n• /cpa status\n• /cf zones\n• /cf dns list <zone_id>\n• /cfdav users\n• /sub list\n\n模块入口默认关闭，可在 Web 后台「模块设置」中启用。"
	default:
		reply = "❓ 无法识别，输入 /help 查看支持的命令"
	}

	m := tgbotapi.NewMessage(chatID, reply)
	if _, err := b.api.Send(m); err != nil {
		log.Printf("发送消息失败 chat=%d: %v", chatID, err)
	}
}