print("Adjustable Fan Speed")
print("By: Nik")
print("Date: 29/4/2024")

# Import libraries 
from machine import Pin, PWM, SoftI2C
import library_oled
import ultrasonic_library
from utime import sleep
import dht

# Pin declaration
sensor = dht.DHT22(Pin(15))
pwm = PWM(Pin(18), freq=50, duty=0)  # Initialize servo motor on pin 18
button_0 = Pin(12, Pin.IN, Pin.PULL_UP)  # Initialize push button on pin 12 (Stop Button)
button_1 = Pin(14, Pin.IN, Pin.PULL_UP)  # Initialize push button on pin 14 (Rotate Slow)
button_2 = Pin(27, Pin.IN, Pin.PULL_UP)  # Initialize push button on pin 27 (Rotate Medium)
button_3 = Pin(26, Pin.IN, Pin.PULL_UP)  # Initialize push button on pin 26 (Rotate Fast)
oled_pin = SoftI2C(scl=Pin(22), sda=Pin(21))
led1 = Pin(2, Pin.OUT)  # Initialize red LED
led2 = Pin(4, Pin.OUT)  # Initialize green LED
TRIG = Pin(25, Pin.OUT)
ECHO = Pin(33, Pin.IN)

# Create an object name for component with library
display = library_oled.SSD1306_I2C(width=128, height=64, i2c=oled_pin, external_vcc=False)
sensor_person = ultrasonic_library.HCSR04(trigger_pin=TRIG, echo_pin=ECHO, echo_timeout_us=500*2*30)

# Variable to track servo state and speed
servo_running = False
speed_factor = 1  # Default speed factor

# Function to control servo motor
def Servo(angle, speed_factor):
    # Calculate duty cycle corresponding to the given angle and speed factor
    duty_cycle = int(((angle) / 180 * 2 + 0.5) / 20 * 1023 * speed_factor)
    # Set duty cycle
    pwm.duty(duty_cycle)

# Interrupt callback function for button press
def button_callback(pin):
    global servo_running, speed_factor
    if pin == button_0:  # Stop Button
        servo_running = False
    elif pin == button_1:  # Rotate Slow
        speed_factor = 0.5
        servo_running = True
    elif pin == button_2:  # Rotate Medium
        speed_factor = 1
        servo_running = True
    elif pin == button_3:  # Rotate Fast
        speed_factor = 2
        servo_running = True

# Register button interrupts
button_0.irq(trigger=Pin.IRQ_FALLING, handler=button_callback)
button_1.irq(trigger=Pin.IRQ_FALLING, handler=button_callback)
button_2.irq(trigger=Pin.IRQ_FALLING, handler=button_callback)
button_3.irq(trigger=Pin.IRQ_FALLING, handler=button_callback)

# Main Program
while True:
    # Measure distance using ultrasonic sensor
    distance = sensor_person.distance_cm()

    # Check if the distance is within the specified range or if the stop button is pressed
    if (0 < distance <= 350 and servo_running) or not button_0.value():
        servo_running = True
    else:
        servo_running = False

    # Check if any button for speed control is pressed
    if not button_1.value() or not button_2.value() or not button_3.value():
        servo_running = True

    # Check if the servo should run
    if servo_running:
        # Rotate servo motor based on speed factor
        for angle in range(0, 181, 1):
            Servo(angle, speed_factor)  # Rotate from 0 to 180
            sleep(0.01)
        for angle in range(180, -1, -1):
            Servo(angle, speed_factor)  # Rotate from 180 to 0
            sleep(0.01)
        
        # Display speed status on OLED when fan is running
        print("------------------")
        print("Fan is running")
        print("\n")
        display.fill(0)  # Clear display (0 is usually black)
        display.text("Fan is running", 13, 20, 1)  # Default text
        display.text("Speed: ", 13, 30, 1)  # Show speed text
        if speed_factor == 0.5:
            display.text("Slow", 70, 30, 1)
        elif speed_factor == 1:
            display.text("Moderate", 70, 30, 1)
        elif speed_factor == 2:
            display.text("High", 70, 30, 1)
        display.show()
        
        # Turn on green LED and turn off red LED
        led1.off()
        led2.on()
    else:
        pwm.duty(0)  # Stop the servo motor
        print("------------------")
        print("Fan is stopped")
        print("\n")
        display.fill(0)  # Clear display (0 is usually black)
        display.text("Fan is stopped", 13, 20, 1)  # Show text (1 is white)
        display.show()
        sleep(1)
        
        # Turn on red LED and turn off green LED
        led1.on()
        led2.off()