##
## gol_display.py
##
## by Kristina Striegnitz
##
## version 2/18/2010
##
## A helper function for visualizing the game of life.
##

import pygame

def run_game(grid, cell_size, on_click, next_gen):
    """
    This function takes a grid of dead and life cells (represented as
    a list of lists; dead cells contain a 0, life cells a 1), the size
    that we want to use to represent each cell, the name of a function
    to be called when the user clicks on the grid, and the function to
    be called to calculate what the next generation looks like.
    """
    
    ## Initialize the pygame submodules and set up the display window.
    pygame.init()
    margin = 2
    width = 200
    height = 200
    go_button_radius = 20

    if len(grid) > 0:
        height = len(grid) * (cell_size + margin) + margin
        if len(grid[0]) > 0:
            width = len(grid[0]) * (cell_size + margin) + 2*margin + 2*go_button_radius
            
    # some grid features
    rows = len(grid)
    if rows > 0:
        cols = len(grid[0])

    # the go button
    go_radius = go_button_radius
    go_x = width - go_radius - margin
    go_y = go_radius + margin
    go = False
    
    my_win = pygame.display.set_mode((width,height))
    clock = pygame.time.Clock()
    timer = 0

    ## The game loop starts here.
    keepGoing = True
    while (keepGoing):

        ## Handle events.

        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                keepGoing = False
            elif event.type == pygame.MOUSEBUTTONDOWN:
                mousex, mousey = pygame.mouse.get_pos()

                # mouse click on the grid
                if (mousex >= margin and mousex <= (margin + cell_size) * cols and
                    mousey >= margin and mousey <= (margin + cell_size) * rows):
                    col = (mousex - margin) / (cell_size + margin)
                    row = (mousey - margin) / (cell_size + margin)
                    # on mouse click call event handler function on_click
                    grid = on_click(grid, row, col)

                # mouse click on the start/stop button
                if (mousex > go_x - go_radius and mousex < go_x + go_radius
                    and mousey > go_y - go_radius and mousey < go_y + go_radius):

                    if go:
                        go = False
                    else:
                        go = True


        ## Update game objects.
        dt = clock.tick()
        timer = timer + dt

        if go and timer > 200:
            grid = next_gen(grid) #, rows, cols)
            timer = 0


        ## Draw picture and update display.

        my_win.fill(pygame.color.Color("lightblue"))

        draw_grid(my_win, grid, cell_size, margin)
        pygame.draw.circle(my_win, pygame.color.Color("green"), (go_x, go_y), go_radius)

        pygame.display.update()

    ## The game loop ends here.

    pygame.quit()


def draw_grid(win, grid, size, margin):
    """
    This function takes a grid representation and draws it. 0 is
    represented as magenta, 1 as orange.
    """
    
    for row_index in range(0,len(grid)):
        for col_index in range(0, len(grid[row_index])):
            if grid[row_index][col_index] == 0:
                color = pygame.color.Color("darkmagenta")
            else:
                color = pygame.color.Color("orange")
            x = col_index*(size+margin) + margin
            y = row_index*(size+margin) + margin
            pygame.draw.rect(win,color,(x, y, size, size))