import time
import math
import random
from pimoroni import Button
from servo import Servo, servo2040

"""
An example of how to move a servo smoothly between random positions.

Press "Boot" to exit the program.
"""

UPDATES = 50            # How many times to update Servos per second
TIME_FOR_EACH_MOVE = 2  # The time to travel between each random value
UPDATES_PER_MOVE = TIME_FOR_EACH_MOVE * UPDATES

SERVO_EXTENT = 80       # How far from zero to move the servo
USE_COSINE = True       # Whether or not to use a cosine path between values

# Create the user button
user_sw = Button(servo2040.USER_SW)

# Create a servo on pin 0
s = Servo(servo2040.SERVO_1)

# Get the initial value and create a random end value between the extents
start_value = s.mid_value()
end_value = random.uniform(-SERVO_EXTENT, SERVO_EXTENT)

update = 0

# Continually move the servo until the user button is pressed
while user_sw.raw() is not True:

    # Calculate how far along this movement to be
    percent_along = update / UPDATES_PER_MOVE

    if USE_COSINE:
        # Move the servo between values using cosine
        s.to_percent(math.cos(percent_along * math.pi), 1.0, -1.0, start_value, end_value)
    else:
        # Move the servo linearly between values
        s.to_percent(percent_along, 0.0, 1.0, start_value, end_value)

    # Print out the value the servo is now at
    print("Value = ", round(s.value(), 3), sep="")

    # Move along in time
    update += 1

    # Have we reached the end of this movement?
    if update >= UPDATES_PER_MOVE:
        # Reset the counter
        update = 0

        # Set the start as the last end and create a new random end value
        start_value = end_value
        end_value = random.uniform(-SERVO_EXTENT, SERVO_EXTENT)

    time.sleep(1.0 / UPDATES)

# Disable the servo
s.disable()