"""Handle inputs from the GPIO pins on the Raspberry Pi and converting them to events to be used in other places (
pygame, etc.)"""
import importlib.util

# If the RPi.GPIO module is not found (aka the program is not running on a Pi), import the fake
# GPIO module instead to prevent a crash.

ON_HARDWARE = None  # Flag to tell other methods if the program is running on hardware or not

try:
    importlib.util.find_spec('RPi.GPIO')
    import RPi.GPIO as GPIO
    ON_HARDWARE = False
except ImportError:
    import pocket_friends.game_files.io.fake_gpio as GPIO
    ON_HARDWARE = False

# Dictionary of all the buttons used and what their corresponding GPIO codes are
BUTTONS = {
    'a': 31,  # A button
    'b': 29,  # B button
    'j_i': 7,  # Joystick in
    'j_u': 11,  # Joystick up
    'j_d': 15,  # Joystick down
    'j_l': 13,  # Joystick left
    'j_r': 16  # Joystick right
}


def setup():
    """Prime the GPIO pins for reading the inputs of the buttons."""
    GPIO.setmode(GPIO.BOARD)

    GPIO.setup(BUTTONS.get('a'), GPIO.IN)
    GPIO.setup(BUTTONS.get('b'), GPIO.IN)
    GPIO.setup(BUTTONS.get('j_i'), GPIO.IN)
    GPIO.setup(BUTTONS.get('j_u'), GPIO.IN)
    GPIO.setup(BUTTONS.get('j_d'), GPIO.IN)
    GPIO.setup(BUTTONS.get('j_l'), GPIO.IN)
    GPIO.setup(BUTTONS.get('j_r'), GPIO.IN)

    GPIO.add_event_detect(BUTTONS.get('a'), GPIO.FALLING)
    GPIO.add_event_detect(BUTTONS.get('b'), GPIO.FALLING)
    GPIO.add_event_detect(BUTTONS.get('j_i'), GPIO.FALLING)
    GPIO.add_event_detect(BUTTONS.get('j_u'), GPIO.FALLING)
    GPIO.add_event_detect(BUTTONS.get('j_d'), GPIO.FALLING)
    GPIO.add_event_detect(BUTTONS.get('j_l'), GPIO.FALLING)
    GPIO.add_event_detect(BUTTONS.get('j_r'), GPIO.FALLING)


def teardown():
    """Clean up the GPIO handler."""
    GPIO.cleanup()


def get_press(button):
    """
    Checks if a given button code has been pressed and returns a bool depending on the state.
    Args:
        button:  button to be detected

    Returns: True if the button is has been pressed, False otherwise

    """
    return GPIO.event_detected(button)