import pyembroidery.EmbPattern as EmbPattern
from pyembroidery.EmbConstant import *
import math


def evaluate_lsystem(symbol, rules, depth):
    if depth <= 0 or symbol not in rules:
        symbol()
    else:
        for produced_symbol in rules[symbol]:
            evaluate_lsystem(produced_symbol, rules, depth - 1)


class Turtle:
    def __init__(self, pattern):
        self.pattern = pattern
        self.angle = 0
        self.x = 0
        self.y = 0
        import math
        self.turn_amount = math.pi / 3

    def forward(self, distance):
        self.x += distance * math.cos(self.angle)
        self.y += distance * math.sin(self.angle)
        self.pattern.add_stitch_absolute(STITCH, self.x, self.y)
        # self.pattern.add_stitch_absolute(SEQUIN_EJECT, self.x, self.y)

    def turn(self, angle):
        self.angle += angle

    def move(self, distance):
        self.x += distance * math.cos(self.angle)
        self.y += distance * math.sin(self.angle)

    def add_gosper(self):
        a = lambda: self.forward(20)
        b = lambda: self.forward(20)
        l = lambda: self.turn(self.turn_amount)
        r = lambda: self.turn(-self.turn_amount)
        initial = lambda: None
        rules = {
            initial: [a],
            a: [a, l, b, l, l, b, r, a, r, r, a, a, r, b, l],
            b: [r, a, l, b, b, l, l, b, l, a, r, r, a, r, b]
        }
        evaluate_lsystem(initial, rules, 3)  # 4

    def add_serp(self):
        a = lambda: self.forward(20)
        b = lambda: self.forward(20)
        l = lambda: self.turn(self.turn_amount)
        r = lambda: self.turn(-self.turn_amount)
        initial = lambda: None
        rules = {
            initial: [a],
            a: [b, l, a, l, b],
            b: [a, r, b, r, a]
        }
        evaluate_lsystem(initial, rules, 3)  # 6


def generate(pattern):
    turtle = Turtle(pattern);
    turtle.add_gosper()
    pattern.add_command(COLOR_BREAK)
    turtle.move(500)
    turtle.add_serp()
    pattern.add_command(SEQUENCE_BREAK)
    pattern.add_command(STOP)
    turtle.move(50)
    turtle.add_serp()
    pattern.add_command(SEQUENCE_BREAK)
    turtle.turn(-math.pi / 3)
    turtle.move(500)
    turtle.add_serp()
    pattern.add_command(COLOR_BREAK)
    turtle.turn(-math.pi / 3)
    turtle.move(500)  # 260, -450
    turtle.add_gosper()
    pattern.add_command(END)