import sys, pygame, math,os,random
from pygame.locals import *
pygame.init()
size = width, height = 1000, 700
screen = pygame.display.set_mode(size)
# set up a bunch of constants
WHITE    = 255,255,255
BLACK    = (  0,   0,   0)
BROWN    = (139,  69,  19)
DARKGRAY = (128, 128, 128)
bullets =[]
reload = 0
speed = 0
walls=[]
BGCOLOR = WHITE
BULLETSPEED = 10
ballrect = pygame.Rect(100,50, 10, 10)
keys=pygame.key.get_pressed()
class Wall:
    def __init__(self, pos):
        walls.append(self)
        self.rect = pygame.Rect(pos[0], pos[1], 16, 16)
class Bullet:
    def __init__(self,pos,speed,size):
        self.pos = pos
        self.speed = speed
        self.size = size
    def move(self):
        self.pos[0] = int(self.pos[0] + self.speed[0])
        self.pos[1] = int(self.pos[1] + self.speed[1])
# standard pygame setup code
pygame.init()
pygame.display.set_caption('Bouncer')

# create image
cannonSurf = pygame.Surface((100, 100))
cannonSurf.fill(BGCOLOR)
pygame.draw.circle(cannonSurf, BLACK, (50, 50), 15) # hole
############################Common knowledge, use of atan2##########################################
'''Thanks to a stupid tiny rounding error since pygame doesn't have infinite precision
I had to use vectors the small 0.1 pixel error would acumulate because of the accumulation by adding the speed'''
def getUnitVector(x1, y1, x2, y2):
        delx = x2 - x1
        dely = y2 - y1
        m = math.sqrt(delx * delx + dely * dely)
        unit = (delx / m, dely / m)
        return unit
level = [
"WWWWWWWWWWWWWWWWWWWW",
"W                  W",
"W         WWWWWW   W",
"W   WWWW       W   W",
"W   W        WWWW  W",
"W WWW  WWWW        W",
"W   W     W W      W",
"W   W     W   WWW WW",
"W   WWW WWW   W W  W",
"W     W   W   W W  W",
"WWW   W   WWWWW W  W",
"W W      WW        W",
"W W   WWWW   WWW   W",
"W     W    E   W   W",
"WWWWWWWWWWWWWWWWWWWW",
]

# Parse the level string above. W = wall, E = exit
x = y = 0
for row in level:
    for col in row:
        if col == "W":
            Wall((x, y))
        if col == "E":
            end_rect = pygame.Rect(x, y, 16, 16)
        x += 16
    y += 16
    x = 0

while True:
    for event in pygame.event.get():
        if event.type == QUIT or keys[pygame.K_ESCAPE]:
            pygame.quit()
            sys.exit()

    # fill the screen to draw from a blank state
    screen.fill(BGCOLOR)

    # draw the cannons pointed at the mouse cursor
    mousex, mousey = pygame.mouse.get_pos()
    startx = 500
    starty = 200

    aim = getUnitVector(startx, starty, mousex, mousey)
    # rotate a copy of the cannon image and draw it
    rotatedSurf = pygame.transform.rotate(cannonSurf,aim)
    rotatedRect = rotatedSurf.get_rect()
    rotatedRect.center = (startnx, start)
    screen.blit(rotatedSurf, rotatedRect)
    if pygame.mouse.get_pressed()[0]:
        if reload>10:
            bx = BULLETSPEED * aim[0]
            by = BULLETSPEED * aim[1]
            bullet = Bullet([startx,starty], [bx,-by],10)
            bullets.append(bullet)
            reload=0
        reload = reload + 1
    # draw the cross hairs over the mouse
    pygame.draw.line(screen, BLACK, (mousex -10, mousey), (mousex + 10, mousey))
    pygame.draw.line(screen, BLACK, (mousex, mousey - 10), (mousex, mousey + 10))
    for wall in walls:
        pygame.draw.rect(screen, (100, 100, 200), wall.rect)
    pygame.draw.rect(screen, (255, 0, 0), end_rect)

#Bullet rect operations
    for b in bullets:
        b.move()
        ballrect = pygame.Rect(b.pos[0],b.pos[1],b.size,b.size)
        '''if ballrect.top < 0 or ballrect.bottom > height:
            b.speed[1] = -b.speed[1]
        if ballrect.right > width or ballrect.left < 0:
            b.speed[0] = -b.speed[0]'''
    #    pygame.draw.circle(screen, BLACK, ballrect.center,b.size, 0)
        pygame.draw.circle(screen, BLACK, b.pos, 1, 0)
    pygame.display.flip()
    pygame.time.wait(10)