import time
import pymysql
import datetime

DB_CONFIG = {
    'host': 'localhost',
    'user': 'root',
    'password': 'password',
    'database': 'mmcl_db',
    'autocommit': True
}

# ==========================================
# [하드웨어 제어부] 
# 라즈베리파이 등 환경에 맞게 GPIO 또는 Serial 연동
# ==========================================
def set_physical_led(green: int, yellow: int, red: int):
    # import RPi.GPIO as GPIO
    # GPIO.output(PIN_GREEN, green)
    # GPIO.output(PIN_YELLOW, yellow)
    # GPIO.output(PIN_RED, red)
    color = "OFF"
    if red: color = "RED"
    elif yellow: color = "YELLOW"
    elif green: color = "GREEN"
    print(f"[HW Relay Control] 물리적 제어 완료: {color} 상태 켜짐")

def get_db_connection():
    try:
        return pymysql.connect(**DB_CONFIG)
    except Exception as e:
        print(f"DB Connection Error: {e}")
        return None

def run_led_agent():
    print("Starting LED (Warning Light) Control Agent...")
    while True:
        conn = get_db_connection()
        if not conn:
            time.sleep(2)
            continue
            
        try:
            with conn.cursor() as cursor:
                # Target 값이 존재하면서 Current와 다를 때만 조회 (핸드쉐이크 요청 감지)
                sql = """SELECT sensor_no, 
                         target_ch1_statusID, value_ch1_statusID,
                         target_ch2_statusID, value_ch2_statusID,
                         target_ch3_statusID, value_ch3_statusID
                         FROM sensor_info 
                         WHERE sensor_typeid = 2 
                         AND (
                             (target_ch1_statusID IS NOT NULL AND target_ch1_statusID != IFNULL(value_ch1_statusID, -1)) OR
                             (target_ch2_statusID IS NOT NULL AND target_ch2_statusID != IFNULL(value_ch2_statusID, -1)) OR
                             (target_ch3_statusID IS NOT NULL AND target_ch3_statusID != IFNULL(value_ch3_statusID, -1))
                         )"""
                cursor.execute(sql)
                tasks = cursor.fetchall()
                
                for task in tasks:
                    sensor_no = task[0]
                    t_ch1, v_ch1 = task[1], task[2] # Green
                    t_ch2, v_ch2 = task[3], task[4] # Yellow
                    t_ch3, v_ch3 = task[5], task[6] # Red
                    
                    print(f"\n[Agent] 제어 명령 감지! (Sensor No: {sensor_no})")
                    
                    # 1. 물리적 하드웨어 제어
                    set_physical_led(t_ch1, t_ch2, t_ch3)
                    time.sleep(0.5) # 물리 스위칭 여유 시간
                    
                    # 2. 제어 성공 후 DB에 상태(Current) 동기화 (핸드쉐이크 완료 응답)
                    new_v1 = t_ch1 if t_ch1 is not None else v_ch1
                    new_v2 = t_ch2 if t_ch2 is not None else v_ch2
                    new_v3 = t_ch3 if t_ch3 is not None else v_ch3
                    
                    update_sql = """UPDATE sensor_info 
                                    SET value_ch1_statusID=%s, value_ch2_statusID=%s, value_ch3_statusID=%s, update_time=%s 
                                    WHERE sensor_no=%s"""
                    cursor.execute(update_sql, (new_v1, new_v2, new_v3, datetime.datetime.now(), sensor_no))
                    print(f"[Agent] DB 상태 동기화 업데이트 완료 -> 파이썬 백엔드로 신호 전달됨")
                    
        except Exception as e:
            print(f"Error: {e}")
        finally:
            conn.close()
            
        time.sleep(1) # 1초 주기로 Polling

if __name__ == "__main__":
    run_led_agent()