"""
Face Recognition Access Control System - Wokwi Simulator
=========================================================
Raspberry Pi Pico Version

This simulates the GPIO behavior of a face recognition door lock system.
Since Wokwi doesn't have a camera module, we use the button to simulate
face detection events.

Hardware Connections:
- GPIO 16: Relay (Door Lock)
- GPIO 17: Green LED (Access Granted)
- GPIO 18: Red LED (Access Denied)
- GPIO 19: Buzzer (Alert)
- GPIO 20: Push Button (Simulate Face Scan / Manual Trigger)
- GPIO 21: Second Button (Simulate Known Face)

How to Test:
1. Press the BLUE button (GP20) to simulate "Unknown Face" → Red LED + Buzzer
2. Press the GREEN button (GP21) to simulate "Known Face" → Green LED + Relay (Unlock)
3. System auto-resets after 3 seconds
"""

from machine import Pin
import time

# ==================== PIN CONFIGURATION ====================
# Output pins
RELAY_PIN = 16      # Door lock relay
GREEN_LED_PIN = 17  # Access granted indicator
RED_LED_PIN = 18    # Access denied indicator
BUZZER_PIN = 19     # Alert buzzer

# Input pins
SCAN_BUTTON_PIN = 20    # Simulate face scan (unknown face)
KNOWN_FACE_PIN = 21     # Simulate known face detection

# ==================== INITIALIZE HARDWARE ====================
# Outputs
relay = Pin(RELAY_PIN, Pin.OUT)
green_led = Pin(GREEN_LED_PIN, Pin.OUT)
red_led = Pin(RED_LED_PIN, Pin.OUT)
buzzer = Pin(BUZZER_PIN, Pin.OUT)

# Inputs (with internal pull-up resistors)
scan_button = Pin(SCAN_BUTTON_PIN, Pin.IN, Pin.PULL_UP)
known_face_button = Pin(KNOWN_FACE_PIN, Pin.IN, Pin.PULL_UP)

# ==================== SYSTEM STATE ====================
class SystemState:
    IDLE = 0
    SCANNING = 1
    ACCESS_GRANTED = 2
    ACCESS_DENIED = 3

current_state = SystemState.IDLE
state_timer = 0

# ==================== HELPER FUNCTIONS ====================
def all_off():
    """Turn off all outputs"""
    relay.value(0)
    green_led.value(0)
    red_led.value(0)
    buzzer.value(0)

def access_granted():
    """Handle successful face recognition"""
    global current_state, state_timer
    print("✅ ACCESS GRANTED - Face Recognized!")
    print("   🔓 Door Unlocked")
    
    # Turn on green LED and relay (unlock door)
    green_led.value(1)
    relay.value(1)
    red_led.value(0)
    buzzer.value(0)
    
    current_state = SystemState.ACCESS_GRANTED
    state_timer = time.ticks_ms()

def access_denied():
    """Handle failed face recognition"""
    global current_state, state_timer
    print("❌ ACCESS DENIED - Unknown Face!")
    print("   🔒 Door Remains Locked")
    
    # Turn on red LED and buzzer (alert)
    red_led.value(1)
    buzzer.value(1)
    green_led.value(0)
    relay.value(0)
    
    current_state = SystemState.ACCESS_DENIED
    state_timer = time.ticks_ms()

def scanning_effect():
    """Visual feedback during scanning"""
    print("🔍 Scanning face...")
    for i in range(3):
        green_led.value(1)
        red_led.value(1)
        time.sleep(0.1)
        green_led.value(0)
        red_led.value(0)
        time.sleep(0.1)

def idle_state():
    """Return to idle state"""
    global current_state
    print("💤 System Ready - Waiting for face scan...")
    all_off()
    current_state = SystemState.IDLE

def flash_red_led():
    """Flash red LED for denied state"""
    red_led.value(not red_led.value())

# ==================== STARTUP SEQUENCE ====================
def startup_sequence():
    """Visual startup test"""
    print("\n" + "="*50)
    print("🚀 Face Recognition Access Control System")
    print("   Raspberry Pi Pico - Wokwi Simulator")
    print("="*50)
    print("\nRunning startup test...")
    
    # Test each component
    print("  Testing Green LED...")
    green_led.value(1)
    time.sleep(0.3)
    green_led.value(0)
    
    print("  Testing Red LED...")
    red_led.value(1)
    time.sleep(0.3)
    red_led.value(0)
    
    print("  Testing Buzzer...")
    buzzer.value(1)
    time.sleep(0.2)
    buzzer.value(0)
    
    print("  Testing Relay...")
    relay.value(1)
    time.sleep(0.3)
    relay.value(0)
    
    print("\n✅ All components OK!")
    print("\n" + "-"*50)
    print("INSTRUCTIONS:")
    print("  🔵 Press BLUE button  → Simulate UNKNOWN face")
    print("  🟢 Press GREEN button → Simulate KNOWN face")
    print("-"*50 + "\n")

# ==================== MAIN LOOP ====================
def main():
    global current_state, state_timer
    
    startup_sequence()
    idle_state()
    
    last_flash = 0
    flash_interval = 200  # ms
    
    while True:
        current_time = time.ticks_ms()
        
        # Check for button presses in IDLE state
        if current_state == SystemState.IDLE:
            # Check for unknown face simulation (blue button)
            if scan_button.value() == 0:
                scanning_effect()
                time.sleep(0.5)  # Simulate processing
                access_denied()
                time.sleep(0.3)  # Debounce
            
            # Check for known face simulation (green button)
            elif known_face_button.value() == 0:
                scanning_effect()
                time.sleep(0.5)  # Simulate processing
                access_granted()
                time.sleep(0.3)  # Debounce
        
        # Handle ACCESS_GRANTED state
        elif current_state == SystemState.ACCESS_GRANTED:
            # Auto-reset after 3 seconds
            if time.ticks_diff(current_time, state_timer) > 3000:
                print("🔒 Door Auto-Locked")
                idle_state()
        
        # Handle ACCESS_DENIED state
        elif current_state == SystemState.ACCESS_DENIED:
            # Flash red LED
            if time.ticks_diff(current_time, last_flash) > flash_interval:
                flash_red_led()
                last_flash = current_time
            
            # Auto-reset after 3 seconds
            if time.ticks_diff(current_time, state_timer) > 3000:
                idle_state()
        
        time.sleep(0.01)  # Small delay to prevent tight loop

# Run the main program
if __name__ == "__main__":
    main()