package handlers

import (
	"fmt"
	"net/http"
	"whatsapp-bot/db"
	"whatsapp-bot/services"

	"github.com/gin-gonic/gin"
)

// Structs to parse incoming WhatsApp Webhook JSON
type WebhookPayload struct {
	Entry []struct {
		Changes []struct {
			Value struct {
				Messages []struct {
					From string `json:"from"`
					Text struct {
						Body string `json:"body"`
					} `json:"text"`
					Type string `json:"type"`
				} `json:"messages"`
			} `json:"value"`
		} `json:"changes"`
	} `json:"entry"`
}

// VerifyWebhook (Keep this as is)
func VerifyWebhook(c *gin.Context) {
	mode := c.Query("hub.mode")
	token := c.Query("hub.verify_token")
	challenge := c.Query("hub.challenge")

	if mode == "subscribe" && token == "YOUR_SECRET_TOKEN" { // CHANGE THIS to match your Meta setup
		c.String(http.StatusOK, challenge)
	} else {
		c.Status(http.StatusForbidden)
	}
}

func HandleMessage(c *gin.Context) {
	var payload WebhookPayload
	if err := c.BindJSON(&payload); err != nil {
		// WhatsApp sends other events (statuses) that might not match. Ignore errors.
		c.Status(200)
		return
	}

	// 1. Loop through messages (usually just one)
	for _, entry := range payload.Entry {
		for _, change := range entry.Changes {
			for _, msg := range change.Value.Messages {

				// We only handle text for now
				if msg.Type != "text" {
					continue
				}

				userPhone := msg.From
				userText := msg.Text.Body

				fmt.Printf("📩 Received from %s: %s\n", userPhone, userText)

				// 2. Identify the Chat Logic
				chatID := db.GetOrCreateChatByPhone(userPhone)

				// 3. Save User Message
				db.Conn.Exec("INSERT INTO messages (chat_id, role, content) VALUES (?, 'user', ?)", chatID, userText)

				// 4. Get AI Response
				// Fetch history
				rows, _ := db.Conn.Query("SELECT role, content FROM messages WHERE chat_id = ? ORDER BY created_at ASC", chatID)
				var history []services.Message
				for rows.Next() {
					var m services.Message
					rows.Scan(&m.Role, &m.Content)
					history = append(history, m)
				}
				rows.Close()

				// Call AI (We don't need the stream callback here, just the final string)
				aiResponse, _ := services.StreamAIResponse(history, func(chunk string) {
					// We can't stream to WhatsApp, so we do nothing here.
				})

				// 5. Save & Send Response
				if aiResponse != "" {
					db.Conn.Exec("INSERT INTO messages (chat_id, role, content) VALUES (?, 'assistant', ?)", chatID, aiResponse)
					err := services.SendWhatsAppMessage(userPhone, aiResponse)
					if err != nil {
						fmt.Println("❌ Error sending to WhatsApp:", err)
					}
				}
			}
		}
	}

	c.Status(200)
}