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 User
	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
	}

	// 🌟 Ambil Role User dari Token
	userRoleInterface, _ := c.Get("role")
	userRole, _ := userRoleInterface.(string)

	// 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
	}

	// =========================================================
	// 🌟 PERBAIKAN: PROTEKSI STATUS MAINTENANCE RUANGAN
	// =========================================================
	var targetRoom models.Room
	if err := config.DB.First(&targetRoom, input.RoomID).Error; err != nil {
		c.JSON(http.StatusNotFound, gin.H{"error": "Ruangan tidak ditemukan di database"})
		return
	}

	if targetRoom.Status == "Maintenance" {
		c.JSON(http.StatusForbidden, gin.H{"error": "Akses Ditolak: Ruangan ini sedang dalam perawatan teknis dan tidak dapat dipesan saat ini."})
		return
	}
	// =========================================================

	// Overlap Check (Mencegah bentrok jadwal)
	var count int64
	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
	}

	// Penentuan Status Otomatis
	statusPeminjaman := "Pending" // Default untuk student
	if userRole == "lecturer" {
		statusPeminjaman = "Approved" // Dosen otomatis disetujui!
	}

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

	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,
	})
}

// Fungsi khusus untuk mengambil riwayat pribadi
func GetMyBookings(c *gin.Context) {
	var bookings []models.Booking

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

	if role == "admin" {
		// Admin bisa melihat semua riwayat
		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 {
		// Mahasiswa/Dosen HANYA BISA melihat riwayat miliknya sendiri
		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
	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
	}

	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 {
		fmt.Println("🔥 ERROR DARI DATABASE:", err.Error())
		c.JSON(http.StatusInternalServerError, gin.H{"error": err.Error()})
		return
	}

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

// INPUT UNTUK ESP32
type TokenInput struct {
	Token string `json:"token" binding:"required"` // Berubah menjadi 'token' menyesuaikan payload ESP32
}

// VERIFIKASI KODE DARI ESP32 (Booking & Jadwal Kuliah)
func VerifyRedeemCode(c *gin.Context) {
	var input TokenInput

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

	loc, _ := time.LoadLocation("Asia/Jakarta")
	currentTime := time.Now().In(loc)
	var endTime time.Time
	var roomName string

	// 1. CARI DI TABEL BOOKING (REDEEM CODE)
	var booking models.Booking
	errBooking := config.DB.Preload("Room").First(&booking, "redeem_code = ? AND status = 'Approved'", input.Token).Error

	if errBooking == nil {
		// LOGIKA BOOKING (Sudah menggunakan time.Time)
		if currentTime.Before(booking.StartTime) {
			c.JSON(http.StatusForbidden, gin.H{"error": "Belum waktunya peminjaman!"})
			return
		}
		if currentTime.After(booking.EndTime) {
			c.JSON(http.StatusForbidden, gin.H{"error": "Waktu peminjaman sudah habis!"})
			return
		}
		endTime = booking.EndTime
		roomName = booking.Room.Name

	} else {
		// 2. JIKA TIDAK KETEMU, CARI DI TABEL JADWAL KELAS (KODE MK)
		var schedule models.ClassSchedule
		errSchedule := config.DB.Preload("Room").First(&schedule, "kode_mk = ?", input.Token).Error

		if errSchedule != nil {
			c.JSON(http.StatusUnauthorized, gin.H{"error": "Token atau Kode MK tidak valid!"})
			return
		}

		// LOGIKA JADWAL KULIAH (Konversi String Jam ke time.Time hari ini)
		todayStr := currentTime.Format("2006-01-02")
		// Gabungkan tanggal hari ini dengan jam dari database (JamMulai & JamSelesai)
		startTime, _ := time.Parse("2006-01-02 15:04:05", todayStr+" "+schedule.JamMulai)
		endTimeParsed, _ := time.Parse("2006-01-02 15:04:05", todayStr+" "+schedule.JamSelesai)

		if currentTime.Before(startTime) {
			c.JSON(http.StatusForbidden, gin.H{"error": "Belum waktunya jadwal kuliah!"})
			return
		}
		if currentTime.After(endTimeParsed) {
			c.JSON(http.StatusForbidden, gin.H{"error": "Waktu perkuliahan sudah habis!"})
			return
		}

		endTime = endTimeParsed
		roomName = schedule.Room.Name
	}

	// 3. HITUNG SISA WAKTU
	sisaWaktuMenit := int(endTime.Sub(currentTime).Minutes())
	if sisaWaktuMenit < 1 {
		sisaWaktuMenit = 1
	}

	c.JSON(http.StatusOK, gin.H{
		"status":           "success",
		"message":          "Token valid!",
		"room":             roomName,
		"duration_minutes": sisaWaktuMenit,
	})
}

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

	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
	}

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