Skripsi_Valentino_5103022014/backend/controllers/hardwarecontroller.go

package controllers

import (
	"bytes"
	"encoding/json"
	"fmt"
	"net/http"
	"os"
	"time"

	mqtt "github.com/eclipse/paho.mqtt.golang"
	"github.com/gin-gonic/gin"
)

// --- STRUKTUR DATA REQUEST ---
type DeviceControlRequest struct {
	Device string `json:"device"`
	Action string `json:"action"`
}

// Struct baru untuk menangkap input Token dari layar ESP32
type VerifyRequest struct {
	Token string `json:"token"`
}

// =========================================================================
// FUNGSI 1: VERIFIKASI HARDWARE & HITUNG SISA WAKTU DINAMIS
// =========================================================================
func VerifyHardwareCode(c *gin.Context) {
	var req VerifyRequest

	// 1. Tangkap JSON { "token": "..." } dari ESP32
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Format token tidak valid"})
		return
	}

	tokenInput := req.Token
	sekarang := time.Now()

	// ---------------------------------------------------------------------
	// 2. LOGIKA DATABASE PENGGANTI (Silakan sesuaikan dengan model GORM-mu)
	// ---------------------------------------------------------------------
	/* // CONTOH ASLI JIKA SUDAH MENGHUBUNGKAN KE DATABASE:
	   var jadwal models.Booking
	   if err := db.Where("token = ?", tokenInput).First(&jadwal).Error; err != nil {
	       c.JSON(http.StatusUnauthorized, gin.H{"error": "Token salah atau tidak ditemukan"})
	       return
	   }
	   jamSelesai := jadwal.JamSelesai 
	*/

	// SIMULASI SEMENTARA (Hapus bagian ini jika query DB di atas sudah aktif):
	// Mengatur jam selesai kelas pada jam 19:00:00 di hari ini sebagai sampel waktu
	jamSelesai := time.Date(sekarang.Year(), sekarang.Month(), sekarang.Day(), 19, 0, 0, 0, sekarang.Location())
	
	// Tampilkan log di terminal backend
	fmt.Printf("[VERIFY] Token masuk: %s | Jam Selesai: %v\n", tokenInput, jamSelesai)
	// ---------------------------------------------------------------------

	// 3. Kalkulasi Selisih Waktu
	selisihWaktu := jamSelesai.Sub(sekarang)
	sisaMenit := int(selisihWaktu.Minutes())

	// 4. Proteksi Jika Waktu Sudah Habis / Kelas Selesai
	if sisaMenit <= 0 {
		c.JSON(http.StatusForbidden, gin.H{"error": "Waktu peminjaman sudah habis"})
		return
	}

	// 5. Kirim balasan ke ESP32 beserta nilai duration_minutes
	c.JSON(http.StatusOK, gin.H{
		"status":           "success",
		"message":          "Token Valid, Akses Diberikan",
		"duration_minutes": sisaMenit,
	})
}

// =========================================================================
// FUNGSI 2: KONTROL DEVICE VIA HOME ASSISTANT & MQTT
// =========================================================================
func ControlHardware(c *gin.Context) {
	var req DeviceControlRequest
	if err := c.ShouldBindJSON(&req); err != nil {
		c.JSON(http.StatusBadRequest, gin.H{"error": "Format data tidak valid"})
		return
	}

	// --- SKENARIO 1: KONTROL LAMPU (Via MQTT ke ESP32 Relay) ---
	if req.Device == "lampu1" || req.Device == "lampu2" {
		broker := os.Getenv("MQTT_BROKER")
		user := os.Getenv("MQTT_USER")
		pass := os.Getenv("MQTT_PASSWORD")

		// Setup Konfigurasi Klien MQTT Golang
		opts := mqtt.NewClientOptions()
		opts.AddBroker(broker)
		opts.SetUsername(user)
		opts.SetPassword(pass)
		opts.SetClientID(fmt.Sprintf("Golang-SCLASS-%d", time.Now().Unix()))

		client := mqtt.NewClient(opts)
		if token := client.Connect(); token.Wait() && token.Error() != nil {
			c.JSON(http.StatusInternalServerError, gin.H{"error": "Golang gagal terhubung ke MQTT Broker"})
			return
		}
		defer client.Disconnect(250)

		// Tentukan Topik
		topic := fmt.Sprintf("sclass/d101/%s", req.Device)

		// Publish Pesan
		token := client.Publish(topic, 0, false, req.Action)
		token.Wait()

		c.JSON(http.StatusOK, gin.H{
			"status":  "success",
			"message": fmt.Sprintf("Berhasil mengirim perintah %s ke %s via MQTT", req.Action, req.Device),
		})
		return
	}

	// --- SKENARIO 2: KONTROL AC & PROYEKTOR (Via Home Assistant) ---
	if req.Device == "ac" || req.Device == "projector" {
		haURL := os.Getenv("HA_URL")
		haToken := os.Getenv("HA_TOKEN")
		var entityID string

		switch req.Device {
		case "ac":
			if req.Action == "on" {
				entityID = "scene.ac_d101_on"
			} else {
				entityID = "scene.ac_d101_off"
			}
		case "projector":
			if req.Action == "on" {
				entityID = "scene.projector_d101_on"
			} else {
				entityID = "scene.projector_d101_off"
			}
		}

		apiURL := fmt.Sprintf("%s/api/services/scene/turn_on", haURL)
		payload := map[string]string{"entity_id": entityID}
		jsonPayload, _ := json.Marshal(payload)

		reqHA, err := http.NewRequest("POST", apiURL, bytes.NewBuffer(jsonPayload))
		if err != nil {
			c.JSON(http.StatusInternalServerError, gin.H{"error": "Gagal membuat request ke HA"})
			return
		}

		reqHA.Header.Set("Authorization", "Bearer "+haToken)
		reqHA.Header.Set("Content-Type", "application/json")

		httpClient := &http.Client{Timeout: 5 * time.Second}
		resp, err := httpClient.Do(reqHA)
		if err != nil {
			c.JSON(http.StatusGatewayTimeout, gin.H{"error": "Gagal menghubungi Home Assistant"})
			return
		}
		defer resp.Body.Close()

		c.JSON(http.StatusOK, gin.H{
			"status":  "success",
			"message": fmt.Sprintf("Berhasil memicu scene %s", entityID),
		})
		return
	}

	// Jika device tidak dikenali
	c.JSON(http.StatusBadRequest, gin.H{"error": "Device tidak dikenali sistem"})
}

// =========================================================================
// FUNGSI 3: MENDAPATKAN STATUS DAYA DARI HOME ASSISTANT
// =========================================================================
func GetPowerStatus(c *gin.Context) {
	haURL := os.Getenv("HA_URL")
	haToken := os.Getenv("HA_TOKEN")
	
	// Ganti dengan Entity ID sensor daya kamu di Home Assistant
	entityID := "sensor.kwh_meter_power" 
	apiURL := fmt.Sprintf("%s/api/states/%s", haURL, entityID)

	req, _ := http.NewRequest("GET", apiURL, nil)
	req.Header.Set("Authorization", "Bearer "+haToken)
	req.Header.Set("Content-Type", "application/json")

	client := &http.Client{}
	resp, err := client.Do(req)
	if err != nil {
		c.JSON(http.StatusInternalServerError, gin.H{"power": 0})
		return
	}
	defer resp.Body.Close()

	var result map[string]interface{}
	json.NewDecoder(resp.Body).Decode(&result)

	// Ambil nilai state (angka watt)
	powerStr, ok := result["state"].(string)
	if !ok {
		c.JSON(http.StatusOK, gin.H{"power": 0})
		return
	}

	c.JSON(http.StatusOK, gin.H{"power": powerStr})
}