game = {
    chg_adv = {x=0, y=0},
    chg_step = 0,
    back_buf = 0,
    circ_buf = 0,

    water_pal = {6,6,21,21,6,21,6,22,22,22,22,22,22,22,22,21,21,22,22,22,22,21,22,22,21,22,22,22,22,6,6,6},
    fade_pal = {1,1,3,1,1,3,29,29,3,3,3,3,3,6,6,29,29,3,3,3,3,29,6,29,29,6,29,6,6,1,1,1},

    light_strobe_value = 0,
    light_strobe_dir = 1,
    water_counter = 0,

    enable = function()
        if game.back_buf == 0 then
            game.back_buf = surf.new(160,104)
            game.circ_buf = surf.new(160,104)
        end
        app.update = game.update
        sys.beat(2)
        --shader.enable();
    end,

    update = function()
        game.water_counter = game.water_counter + 0.05

        view.origin(0,0)
        surf.target(0)
        view.clip()

        score.draw()
        surf.target(game.back_buf)

        -- Pintar el mapa i sprites
        rooms.draw()
		sprites.update()

        game.apply_water()
        game.apply_light()

        if key.press(key.ESCAPE) or key.press(key.F9) then
            rooms.retrieve_original_items()
            editor.enable()
        end
    end,

    change_room = function(x,y)
        game.chg_adv.x = x*0.25
        game.chg_adv.y = y*0.25
        game.chg_step = 8*4
        sprites.pause_ia = true
        -- [TODO] Crear els sprites per als items de l'habitació a la que entrem
        sprites.add_from_room(rooms.pos.x+x*20, rooms.pos.y+y*12)
        app.push(game.update_change_room)
        --sys.beat(10)
    end,

    update_change_room = function()
        --if not sys.beat() then return end
        view.origin(0,0)
        surf.target(0)
        view.clip()

        score.draw()
        surf.target(game.back_buf)
        --view.clip()

        -- Pintar el mapa i sprites
        rooms.pos.x = rooms.pos.x + (game.chg_adv.x*2.5)
        rooms.pos.y = rooms.pos.y + (game.chg_adv.y*1.5)
        sprites.hero.pos.x = sprites.hero.pos.x + game.chg_adv.x
        sprites.hero.pos.y = sprites.hero.pos.y + game.chg_adv.y

        rooms.draw()
		sprites.update()
        game.apply_water()
        game.apply_light()

        game.chg_step = game.chg_step - 1
        if game.chg_step == 0 then
            sprites.remove_out_of_room()
            sprites.pause_ia = false
            app.pop()
            --sys.beat(2)
        end
    end,

    draw_light = function(x,y,size)
        surf.target(game.circ_buf)
        local s = size+(game.light_strobe_value/2)
        draw.mode(draw.OR)
        draw.circf(x,y,s,1)
        draw.circf(x,y,2*(s/3),2)
        draw.mode(draw.NORMAL)
        surf.target(game.back_buf)
    end,

    apply_water = function()
        view.origin(0,0)
        if rooms.pos.y == 84 then
            surf.target(game.back_buf)
            surf.source(game.back_buf)
            for x=0,159 do
                local water_level = math.sin(game.water_counter)*2
                for y=96+water_level,103 do
                    local pixel = surf.pixel(x,y)
                    surf.pixel(x,y,game.water_pal[pixel+1])
                end
            end
        end
    end,

    apply_light = function()
        game.light_strobe_value = game.light_strobe_value + game.light_strobe_dir
        if math.abs(game.light_strobe_value)==2 then
            game.light_strobe_dir = -game.light_strobe_dir
        end

        surf.target(0)
        for y=0,103 do
            for x=0,159 do
                surf.source(game.back_buf)
                local pixel = surf.pixel(x,y)
                surf.source(game.circ_buf)
                local light = surf.pixel(x,y)
                if light==0 then
                    surf.pixel(x,y,1)
                elseif (light&2)==2 then
                    surf.pixel(x,y,pixel)
                else
                    surf.pixel(x,y,game.fade_pal[pixel+1])
                end
            end
        end
    end


}