from machine import Pin # Import Pin library for GPIO programming
from machine import PWM # Import PWM library for PWM programming
from utime import sleep_ms
from tones import tones # To get frequencies for various musical notes

# GPIO pin the buzzer is connected to
BUZZER_PIN = 15

# Exercise 1.1: FILL CODE HERE to use PWM() to enable PWM on GPIO output pin: BUZZER_PIN 
buzzer = PWM(Pin(BUZZER_PIN, Pin.OUT))

# A list of musical notes for the song, where tuple represents the note and its duration in ms
song = [
    ('C4', 400), ('E4', 200), ('G4', 400), ('A4', 400),
    ('G4', 400), ('E4', 200), ('D4', 400), ('C4', 400),
    ('G4', 400), ('A4', 200), ('C5', 400), ('E5', 400),
    ('D5', 400), ('C5', 200), ('A4', 400), ('G4', 400),
    ('C4', 400), ('E4', 200), ('G4', 400), ('A4', 400),
    ('G4', 400), ('E4', 200), ('D4', 400), ('C4', 400),
]

# Programs the PWM parameters: duty cycle and frequency for the given musical note
def playtone(frequency, duration):
    # Uncomment below to debug
    #print("Playing tone:", frequency)

    # The duty cycle is adjusted based on the frequency
    # to maintain a balance between pitch and loudness.
    buzzer.duty_u16(int(frequency))

    # Exercise 1.2: FILL CODE HERE use PWM's freq API to set the frequency 
    buzzer.freq(frequency)

    # Use sleep as a nop to play the note for the specified duration
    sleep_ms(duration) 


# Turn off the buzzer by programming the duty cycle
def bequiet():
    # Uncomment below to debug
    # print("Be quiet")
    
    # Exercise 1.3: FILL CODE HERE: Use duty_u16() API to turn off Buzzer
    buzzer.duty_u16(0)

   

# Play the melody
def playsong(mysong):
    print("Playing song")
    for note, duration in mysong:
        if (note == "P"):
            bequiet()
        else:
            playtone(tones[note], duration)
    bequiet()


# Exercise 1: Enable the below code to play the song on every run
playsong(song)


# #Exercise 2: Timer based alarm
# from machine import Timer
# def interruption_handler(timer):
#     playsong(song)

# # Make sure the period timer is beyond the length of the song
# # Switch b/w one-shot or periodic
# if __name__ == "__main__":
#     periodic_timer = Timer(mode=Timer.PERIODIC, period=8000, callback=interruption_handler)
#     one_shot_timer = Timer(mode=Timer.ONE_SHOT, period=5000, callback=interruption_handler)