'''
Mission 5 Line Sense
Final program with changes
'''
from botcore import *
from time import sleep
from random import randrange

threshold = 2000
line_count = 0

def detect_line(n):
    val = ls.read(n)
    is_detected = val < threshold
    leds.ls_num(n, is_detected)
    return is_detected

def scan_lines():
    got_line = False
    n_sens = 0
    while n_sens < 5:
        if detect_line(n_sens):
            got_line = True
        n_sens = n_sens + 1
    return got_line

def go_forward(speed):
    motors.run(LEFT, speed)
    motors.run(RIGHT, speed)

def back_turn(speed, delay):
    motors.run(LEFT, -speed)
    motors.run(RIGHT, -speed)
    sleep(1.5)
    motors.run(LEFT, speed)
    motors.run(RIGHT, -speed)
    sleep(delay)

# -- Main Program --
motors.enable(True)

while True:
    if buttons.was_pressed(0):
        break

while True:
    hit = scan_lines()

    if hit:
        back_turn(20, 1.3)

        line_count = line_count + 1
        if line_count == 256:
            line_count = 0
        leds.user(line_count)
    else:
        speed = randrange(30, 50)
        go_forward(speed)