# typeface.py
# By Chris Proctor and _________

# Contains one function for each letter in the English alphabet. 
# Each function should draw its letter at a scale of `unit`, and then 
# return back to the same position and heading where it started. 

# Note: The `sqrt` function from math may be helpful--if you want to 
# move the turtle along the diagonal of a square with side length x, 
# the turtle should move a distance of sqrt(x)
from turtle import *
from math import sqrt

def fly(unit):
    penup()
    fd(unit)
    pendown()

def flyto(x, y):
    penup()
    goto(x, y)
    pendown()

def triangle(unit):
    "Draws a 2x1 isocolese triangle"
    lt(45)
    fd(unit * sqrt(2))
    rt(90)
    fd(unit * sqrt(2))
    rt(135)
    fd(2 * unit)
    rt(180)

def curve(vertical_units, diagonal_units, horizontal_units, right_turn=True):
    "Draws a curve to the right: up, diag, horizontal, diag, down."
    turn = right if right_turn else left
    fd(vertical_units)
    turn(45)
    fd(diagonal_units * sqrt(2))
    turn(45)
    fd(horizontal_units) 
    turn(45)
    fd(diagonal_units * sqrt(2))
    turn(45)
    fd(vertical_units)

def draw_letter_a(unit):
    fly(unit)
    lt(90)
    fd(unit*3)
    curve(unit*3, unit*2, unit*2)
    curve(unit*3, 0, unit*2)
    lt(90)
    fd(unit*2)
    lt(90)
    curve(unit*3, 0, unit*2)
    fd(unit)
    rt(90)
    fly(2*unit)
    lt(90)
    curve(unit, unit, 0)
    rt(90)
    fd(2*unit)
    fly(unit*3)
    lt(90)
    fly(4*unit)
    lt(90)

def draw_letter_b(unit):
    fly(unit)
    lt(90)
    fd(8*unit)
    rt(90)
    fd(2*unit)

    # bubbles
    rt(90)
    fly(unit)
    lt(90)
    curve(unit, unit, 0)
    rt(90)
    fd(2*unit)
    rt(180)
    fly(4*unit)
    lt(90)
    curve(unit, unit, 0)
    rt(90)
    fd(2*unit)
    fly(5*unit)
    rt(90)

    # right side
    fd(2*unit)
    curve(0, 2*unit, 0)
    rt(180)
    curve(0, 2*unit, 0)
    fd(4*unit)

    fly(unit)
    rt(180)


def draw_letter_c(unit):
    fly(7*unit)
    rt(180)
    curve(4*unit, 2*unit, 4*unit)
    rt(90)
    fd(2*unit)
    fly(4*unit)
    rt(90)
    curve(3*unit, unit, 2*unit)
    rt(90)
    fly(4*unit)
    fd(2*unit)
    rt(90)
    fly(7*unit)
    rt(180)

def draw_letter_d(unit):
    fly(unit)
    lt(90)
    fd(8*unit)
    rt(90)
    curve(4*unit, 2*unit, 4*unit)
    bk(2*unit)
    rt(90)
    fly(2*unit)
    fd(4*unit)
    rt(90)
    curve(unit, unit, 2*unit)
    fly(3*unit)
    lt(90)
    fly(2*unit)
    lt(90)

def draw_letter_e(unit):
    fly(3*unit)
    rt(180)
    curve(2*unit, 0, 8*unit)
    curve(4*unit, 0, 2*unit)
    curve(0, 0, -unit)
    curve(4*unit, 0, 2*unit)
    curve(0, 0, -unit)
    curve(4*unit, 0, 2*unit)
    fly(3*unit)
    rt(180)

def draw_letter_f(unit):
    fly(3*unit)
    rt(180)
    curve(2*unit, 0, 8*unit)
    curve(4*unit, 0, 2*unit)
    curve(0, 0, -unit)
    curve(4*unit, 0, 2*unit)
    lt(90)
    fd(3*unit)
    rt(90)
    fly(3*unit)
    rt(180)

def draw_letter_g(unit):
    fly(7*unit)
    rt(180)
    curve(4*unit, 2*unit, 4*unit)
    rt(90)
    fd(2*unit)
    rt(90)
    fd(2*unit)
    curve(unit, unit, 2*unit, False)
    lt(90)
    curve(2*unit, 0, 2*unit)
    fd(2*unit)
    rt(90)
    fly(7*unit)
    rt(180)

def draw_letter_h(unit):
    pass

def draw_letter_i(unit):
    pass

def draw_letter_j(unit):
    pass

def draw_letter_k(unit):
    pass

def draw_letter_l(unit):
    pass

def draw_letter_m(unit):
    pass

def draw_letter_n(unit):
    pass

def draw_letter_o(unit):
    pass

def draw_letter_p(unit):
    pass

def draw_letter_q(unit):
    pass

def draw_letter_r(unit):
    pass

def draw_letter_s(unit):
    pass

def draw_letter_t(unit):
    pass

def draw_letter_u(unit):
    pass

def draw_letter_v(unit):
    pass

def draw_letter_w(unit):
    pass

def draw_letter_x(unit):
    pass

def draw_letter_y(unit):
    pass

def draw_letter_z(unit):
    pass