import machine
import time
from ssd1306 import SSD1306_I2C

# Pin Setup
BUTTON_PIN = 14
BUZZER_PIN = 15

# Configure Hardware
button = machine.Pin(BUTTON_PIN, machine.Pin.IN, machine.Pin.PULL_UP)
buzzer = machine.Pin(BUZZER_PIN, machine.Pin.OUT)
i2c = machine.I2C(1, scl=machine.Pin(27), sda=machine.Pin(26), freq=400000)

# Initialize 128x64 OLED Screen
oled = SSD1306_I2C(128, 64, i2c)

# Global Variables
queue_number = 0
last_press_time = 0

def update_display(num):
    """Refreshes text layout on the screen."""
    oled.fill(0)
    oled.text("QUEUE SYSTEM", 16, 5)
    oled.text("----------------", 0, 18)
    oled.text("NOW SERVING:", 16, 32)
    oled.text(f"TICKET #{num:03d}", 24, 48)
    oled.show()

def alert_next_patient(num):
    """Sounds the physical buzzer and sends high-level text for audio generation."""
    # Print out Serial window to trigger web app audio engine
    print(f"ANNOUNCE: Now serving ticket number {num}")
    
    # Pulse the active buzzer twice
    for _ in range(2):
        buzzer.value(1)
        time.sleep(0.15)
        buzzer.value(0)
        time.sleep(0.1)

# Display Baseline Initial State
update_display(queue_number)

print("System Active. Press the Button or use the Web Input to call patients.")

while True:
    # Debounced button logic
    if not button.value():
        current_time = time.ticks_ms()
        # 300ms debounce buffer time window
        if time.ticks_diff(current_time, last_press_time) > 300:
            queue_number += 1
            update_display(queue_number)
            alert_next_patient(queue_number)
            last_press_time = current_time
            
    time.sleep(0.05)