FLOOR = 0
GOAL = 1
BOX = 2
PLAYER = 4
WALL = 7

function init()
    mode(2)
    setchar(127,0xee,0xee,0xee,0x00,0xbb,0xbb,0xbb,0x00)
    setchar(16,0xff,0xc3,0xa5,0x99,0x99,0xa5,0xc3,0xff)
    menu.init()
end

-- ====================================================================================================
-- MENU (game state)
-- ====================================================================================================
menu={
    init = function()
        rst()
        update=menu.update
    end,

    update = function()
        color(15,0) cls()
        ink(1)  print("\x20\x20\x20\x87\x81\x87\x85\x85\x85\x87\x85\x87\x85\x87\x85\x87\x84\x20\x20\x20",0,2)
        ink(9)  print("\x20\x20\x20\x83\x85\x85\x85\x8D\x81\x85\x85\x87\x84\x8D\x85\x85\x85\x20\x20\x20",0,3)
        ink(11) print("\x20\x20\x20\x83\x81\x83\x81\x81\x81\x83\x81\x83\x81\x81\x81\x81\x81\x20\x20\x20",0,4)
        ink(15*flr((cnt()%60)/30)) print("PRESS SPACE TO PLAY",1,9)

        if btnp(KEY_SPACE) then
            level.start()
            game.init()
        end
    end
}

-- ====================================================================================================
-- GAME (game state)
-- ====================================================================================================
game={
    init = function()
        update=game.update
        level.load()
    end,
    
    update = function()
        border(0)
        color(1,0)
        cls()
        level.draw()
    
        if btnp(KEY_UP) then level.try_move(0,-1)
        elseif btnp(KEY_DOWN) then level.try_move(0,1)
        elseif btnp(KEY_LEFT) then level.try_move(-1,0)
        elseif btnp(KEY_RIGHT) then level.try_move(1,0)
        end
    end
}

-- ====================================================================================================
-- LOADING (game state)
-- ====================================================================================================
loading = {
    init = function()
        border(15)
        update=loading.update
        rst()
    end,
    
    update = function()
        color(15,0)
        cls()
        print("LEVEL "..num_level,6,5)
        print("GOOD JOB!",5,8)
        if (cnt()%60)<15 then print("\248",9,10)
        elseif (cnt()%60)<30 then print("\250",9,10)
        elseif (cnt()%60)<45 then print("\248",9,10)
        else print("\251",9,10) end
        if cnt()==120 then
            level.next()
            game.init()
        end
    end
}


-- ====================================================================================================
-- LEVEL
-- ====================================================================================================
levels= {
    "####|# .#|#  ###|#*@  #|#  $ #|#  ###|####",
    "######|#    #|# #@ #|# $* #|# .* #|#    #|######",
    "  ####|###  ####|#     $ #|# #  #$ #|# . .#@ #|#########",
    "########|#      #|# .**$@#|#      #|#####  #|    ####",
    " #######| #     #| # .$. #|## $@$ #|#  .$. #|#      #|########",
    "###### #####|#    ###   #|# $$     #@#|# $ #...   #|#   ########|#####",
    "#######|# .$. #|# $.$ #|# .$. #|# $.$ #|#  @  #|#######",
    "#####|#.  ##|#@$$ #|##   #| ##  #|  ##.#|   ###"
}

level = {
    start = function() num_level=1 end,
    next = function() num_level=num_level+1 end,

    load = function()
        local str = levels[num_level]
        player={}
        map={}
        local pos=0
        local y,x=1,1
        local maxx=0
        map[y] = {}
        while pos<#str do
            local chr = ascii(str,pos)
            if chr == 35 then map[y][x] = WALL end
            if chr == 64 then player.x,player.y=x,y map[y][x] = FLOOR end
            if chr == 43 then player.x,player.y=x,y map[y][x] = GOAL end
            if chr == 36 then map[y][x] = BOX end
            if chr == 42 then map[y][x] = GOAL+BOX end
            if chr == 46 then map[y][x] = GOAL end
            if chr == 32 then map[y][x] = FLOOR end
            if chr == 124 then
                y=y+1
                map[y] = {}
                if maxx < x then maxx=x end
                x=0
            end
            pos=pos+1
            x=x+1
        end
        ox = flr((20-maxx)/2)
        oy = flr((15-y)/2)
    end,

    draw = function()
        for y=1,#map do
            for x=1,#map[y] do
                if map[y][x] == WALL then color(4,0) print("\127",ox+x-1,oy+y-1)
                elseif map[y][x] == BOX then color(8,7) print("\016",ox+x-1,oy+y-1)
                elseif map[y][x] == BOX+GOAL then color(3,11) print("\016",ox+x-1,oy+y-1)
                elseif map[y][x] == GOAL then color(3,0) print("\144",ox+x-1,oy+y-1)
                end
            end
        end
        color(15,0) print("\248",ox+player.x-1,oy+player.y-1)
    end,

    try_move = function(x,y)
        if level.is_empty(x,y) then
            level.move_player(x,y)
        elseif level.is_box(x,y) and level.is_empty(x*2,y*2) then
            level.move_box(x,y)
        end
    end,

    is_empty = function(x,y)
        return map[player.y+y][player.x+x] < 2
    end,
    
    is_box = function(x,y)
        return map[player.y+y][player.x+x] < 4
    end,
    
    move_player = function(x,y)
        player.x=player.x+x
        player.y=player.y+y 
    end,
    
    move_box = function(x,y)
        map[player.y+y*2][player.x+x*2] = map[player.y+y*2][player.x+x*2] + BOX
        map[player.y+y][player.x+x] = map[player.y+y][player.x+x] - BOX
        level.move_player(x,y)
        level.check_finished()
    end,
    
    check_finished = function()
        for y=1,#map do
            for x=1,#map[y] do
                if map[y][x] == GOAL then return end
            end
        end
        loading.init()
    end
}