-- vim: expandtab tabstop=4 shiftwidth=4 softtabstop=4 autoindent:

-- Callback functions
-- see http://www.love2d.org/wiki/Tutorial:Callback_Functions
--
-- for key constants, see http://www.love2d.org/wiki/KeyConstant
--
-- love.load() - at the game's start, used to initialise ressources 
-- love.update(dt) - the game loop function, where "dt" stands
--    for the fraction of seconds since the function was called last
-- love.draw() - graphics output loop
-- love.mousepressed(x, y, button) - mouse down event callback function,
--    where x, y the mouse's position, and button the number of the 
--    button pressed. 
-- love.mousereleased(x, y, button) - mouse button release event callback function, 
--    see mousepressed
-- love.keypressed(key) - key press event callback function, where key is either 
--    a character, or any of the constants like "up", "down", "left", "right"
-- love.keyreleased(key) - key release event callback function - see keypressed
-- love.focus(f) - windows focus received/lost event callback function, where f 
--    is a boolean (true = focus gained, false = focus lost) 
-- love.quit - windows close event callback function


function love.load()
    local init = require("init")
    init.load()
end


function turnLeft(direction)
    if direction == "left" then
        newDirection = "down"
    end
    if direction == "down" then
        newDirection = "right"
    end
    if direction == "right" then
        newDirection = "up"
    end
    if direction == "up" then 
        newDirection = "left"
    end

    return newDirection
end

function turnRight(direction)
    if direction == "left" then
        newDirection = "up"
    end
    if direction == "down" then
        newDirection = "left"
    end
    if direction == "right" then
        newDirection = "down"
    end
    if direction == "up" then 
        newDirection = "right"
    end

    return newDirection
end


function movePlayer(x, y, toDirection)
    if toDirection == "left" then
        x = x - 1 
    end
    if toDirection == "right" then
        x = x + 1
    end
    if toDirection == "up" then
        y = y - 1
    end
    if toDirection == "down" then
        y = y + 1
    end
    return x, y
end


function love.keypressed(key)
    if key == p1_keyleft then
        p1_direction = turnLeft(p1_direction)
    end

    -- what happens if p1 presses right?
    if key == p1_keyright then
        p1_direction = turnRight(p1_direction)
    end

    -- what happens if p2 presses left?
    if key == p2_keyleft then
        p2_direction = turnLeft(p2_direction)
    end

    -- what happens if p2 presses right?
    if key == p2_keyright then
        p2_direction = turnRight(p2_direction)
    end
end

function statePlayer(currentstate)


    if collisionArray[x1][y1] == 0 then
    else
        p1_state = "crashed"
    end


end

function love.update(dt)

    if love.keyboard.isDown(game_keyquit) then
        love.event.quit()
    end

    -- Handle collision Array. 
    --    TODO: Implement collision detection 

    if (p1_state == "alive" and p2_state == "alive") then

        -- Player 1
        x1, y1 = movePlayer(x1, y1, p1_direction)
        if (y1 >= maxHeight) or (y1 <= 0) or (x1 >= maxWidth) or (x1 <= 0) then
            p1_state = "crashed"
        end
        if not (p1_state == "crashed") then
            if collisionArray[x1][y1] > 0 then
                p1_state = "crashed"
            else
                collisionArray[x1][y1] = 1
            end
        end

        -- Player 2 
        x2, y2 = movePlayer(x2, y2, p2_direction)
        if (y2 >= maxHeight) or (y2 <= 0) or (x2 >= maxWidth) or (x2 <= 0) then
            p2_state = "crashed"
        end
        if not (p2_state == "crashed") then
            if collisionArray[x2][y2] > 0 then
                p2_state = "crashed"
            else
                collisionArray[x2][y2] = 2
            end
        end

    end

end

function love.draw()

    -- Players play in canvas ...
    love.graphics.setCanvas(canvas)

    -- Player 1
    love.graphics.setColor(p1_color)
    love.graphics.point(x1, y1)

    -- Player 2
    love.graphics.setColor(p2_color)
    love.graphics.point(x2, y2)

    -- Back to the screen
    love.graphics.setCanvas()

    love.graphics.setBackgroundColor(bg_color)

    -- Border
    love.graphics.setColor(border_color)
    love.graphics.rectangle("line", 0, 0, maxWidth - 1, maxHeight - 1)

    -- Draw the Player Canvas
    love.graphics.setColor(255, 255, 255, 255)
    love.graphics.draw(canvas)

    -- Some Text over the Canvas
    love.graphics.setColor(text_color)
    love.graphics.print ('p1:' .. p1_state .. ' p2:' .. p2_state , 25, 25) 

end