package controllers

import (
	"fmt"
	"net/http"
	"s-class-backend/config"
	"s-class-backend/helpers"
	"s-class-backend/models"
	"time"

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

type BookingInput struct {
	RoomID    uint      `json:"room_id" binding:"required"`
	StartTime time.Time `json:"start_time" binding:"required"`
	EndTime   time.Time `json:"end_time" binding:"required"`
	Purpose   string    `json:"purpose" binding:"required"`
}

func CreateBooking(c *gin.Context) {
	var input BookingInput
	if err := c.ShouldBindJSON(&input); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": err.Error()})
		return
	}

	//Handle UUID
	userIDInterface, exists := c.Get("user_id")
	if !exists {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "User ID tidak ditemukan"})
		return
	}

	userIDStr, ok := userIDInterface.(string)
	if !ok {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Format User ID token salah"})
		return
	}

	userID, err := uuid.Parse(userIDStr)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Gagal memproses User ID"})
		return
	}

	// Validasi Waktu
	if input.EndTime.Before(input.StartTime) {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Waktu selesai tidak boleh lebih awal dari waktu mulai!"})
		return
	}

// (Overlap Check)
	var count int64
	// KITA UBAH STATUSNYA MENJADI: status IN ('Pending', 'Approved')
	config.DB.Model(&models.Booking{}).Where(
		"room_id = ? AND status IN ('Pending', 'Approved') AND ((start_time < ? AND end_time > ?) OR (start_time < ? AND end_time > ?) OR (start_time >= ? AND end_time <= ?))",
		input.RoomID, input.EndTime, input.StartTime, input.EndTime, input.StartTime, input.StartTime, input.EndTime,
	).Count(&count)

	if count > 0 {
		c.JSON(http.StatusConflict, gin.H{"error": "Ruangan sudah dibooking atau sedang dalam antrean persetujuan pada jam tersebut!"})
		return
	}

	// Simpan Booking
	booking := models.Booking{
		UserID:    userID,
		RoomID:    input.RoomID,
		StartTime: input.StartTime,
		EndTime:   input.EndTime,
		Purpose:   input.Purpose,
		Status:    "Pending",
	}

	if err := config.DB.Create(&booking).Error; err != nil {
		fmt.Println("Error DB:", err)
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"message": "Booking Berhasil diajukan!",
		"data":    booking,
	})
}

func GetUserBookings(c *gin.Context) {
	var bookings []models.Booking

	userID, _ := c.Get("user_id")
	role, _ := c.Get("role")

	if role == "admin" {
		if err := config.DB.Preload("Room").Preload("User").Order("created_at desc").Find(&bookings).Error; err != nil {
			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
			return
		}
	} else {
		if err := config.DB.Preload("Room").Where("user_id = ?", userID).Order("created_at desc").Find(&bookings).Error; err != nil {
			c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
			return
		}
	}

	c.JSON(http.StatusOK, gin.H{"data": bookings})
}

type UpdateStatusInput struct {
	Status string `json:"status" binding:"required"`
}

// UPDATE STATUS (ADMIN)
func UpdateBookingStatus(c *gin.Context) {
	bookingID := c.Param("id")

	var input UpdateStatusInput
	if err := c.ShouldBindJSON(&input); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Format data salah"})
		return
	}

	var booking models.Booking
	// KUNCI PERBAIKAN: Gunakan Where("booking_id = ?") agar tepat sasaran
	if err := config.DB.Where("booking_id = ?", bookingID).First(&booking).Error; err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "Data booking tidak ditemukan di database"})
		return
	}

	// Gunakan Switch Case (Clean Code) yang sudah kita bahas sebelumnya
	switch input.Status {
	case "Approved":
		if booking.RedeemCode == "" {
			booking.RedeemCode = helpers.GenerateRedeemCode()
		}
	case "Rejected", "Cancelled":
		booking.RedeemCode = ""
	}

	booking.Status = input.Status

	if err := config.DB.Save(&booking).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": "Gagal menyimpan ke database"})
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"message": "Status booking berhasil diperbarui!",
		"data":    booking,
	})

	booking.Status = input.Status

	// KITA BUKA KEDOK ERROR DARI POSTGRESQL:
	if err := config.DB.Save(&booking).Error; err != nil {
		fmt.Println("🔥 ERROR DARI DATABASE:", err.Error())                  // Cetak teks merah di terminal
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()}) // Tembak ke pop-up web
		return
	}

	c.JSON(http.StatusOK, gin.H{
		"message": "Status booking berhasil diperbarui!",
		"data":    booking,
	})
}

// INPUT UNTUK ESP3
type RedeemInput struct {
	RedeemCode string `json:"redeem_code" binding:"required"`
}

// VERIFIKASI KODE DARI ESP32
func VerifyRedeemCode(c *gin.Context) {
	var input RedeemInput

	if err := c.ShouldBindJSON(&input); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Format data salah"})
		return
	}

	var booking models.Booking

	if err := config.DB.Preload("Room").First(&booking, "redeem_code = ? AND status = 'Approved'", input.RedeemCode).Error; err != nil {
		c.JSON(http.StatusUnauthorized, gin.H{"error": "Kode tidak valid, belum disetujui, atau sudah digunakan!"})
		return
	}

	booking.Status = "Completed"
	booking.RedeemCode = ""
	config.DB.Save(&booking)

	c.JSON(http.StatusOK, gin.H{
		"message": "Kode valid!",
		"room":    booking.Room.Name,
		"status":  "success",
	})
}

// GET ALL BOOKINGS (Untuk Calendar View semua user)
func GetAllBookings(c *gin.Context) {
	var bookings []models.Booking

	// Preload digunakan untuk mengambil data Relasi (Nama Ruangan & Nama Peminjam)
	if err := config.DB.Preload("Room").Preload("User").Order("created_at desc").Find(&bookings).Error; err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

	// Perhatikan: responsenya menggunakan "data: bookings" agar cocok dengan Frontend React-mu
	c.JSON(http.StatusOK, gin.H{
		"status": "success",
		"data":   bookings,
	})
}