batman = {
    states = {IDLE=1, WALK=2, JUMP=3, FALL=4, FALLTHROUGH=5, STAIRS_IDLE=6, STAIRS_MOVING=7},
    x = 7*8,
    y = 14*8,
    surface = nil,
    flip = false,
    frames = {0},
    frame = 1,
    state = 1,
    jump_counter = 0,
    ignore_first_tile = 0,

    init = function()
        batman.surface = surf.load("batman.gif")
        batman.frames = {0,1,2,3}
    end,

    draw = function()
        surf.source(batman.surface)
        local f = batman.frames[batman.frame]
        draw.surf((f%8)*16,(f//8)*16,16,16,batman.x,batman.y,16,16,batman.flip)
        local tx1, tx2, ty = ((batman.x+4)//8), ((batman.x+10)//8), ((batman.y+16)//8)
        draw.rect((tx1)*8,ty*8,8,8, 4)
        draw.rect((tx2)*8,ty*8,8,8, 4)
    end,

    update = function()
        batman.frame = batman.frame + 1
        if batman.frame > #batman.frames then batman.frame = 1 end

        -- Si està IDLE
        if batman.state == batman.states.IDLE then
            -- Mirem si comença a caminar
            if key.down(key.RIGHT) then
                batman.state = batman.states.WALK
                batman.frames = {0,1,2,3}
                batman.frame = 1
            elseif key.down(key.LEFT) then
                batman.state = batman.states.WALK
                batman.frames = {0,1,2,3}
                batman.frame = 1
            elseif key.down(key.DOWN) then
                local tx, ty = ((batman.x+4)//8), ((batman.y+8)//8)
                if (mapa.isStairs(tx,ty)) then
                    batman.state = batman.states.STAIRS_IDLE
                    batman.frames = {10}
                    batman.frame = 1
                    batman.x = ((batman.x+4)//8)*8
                    if (mapa.isStairs(tx-1,ty)) then
                        batman.x = batman.x - 8
                    end
                elseif key.down(key.X) then
                    local tx, ty = ((batman.x+4)//8), ((batman.y+24)//8)
                    if (not mapa.isSolid(tx,ty)) then
                        batman.state = batman.states.FALL
                        batman.ignore_first_tile = 4
                    end
                end
            elseif key.down(key.UP) then
                local tx, ty = ((batman.x+4)//8), ((batman.y)//8)
                if (mapa.isStairs(tx,ty)) then
                    batman.state = batman.states.STAIRS_IDLE
                    batman.frames = {10}
                    batman.frame = 1
                    --batman.x = (batman.x//8)*8
                    batman.x = ((batman.x+4)//8)*8
                    if (mapa.isStairs(tx-1,ty)) then
                        batman.x = batman.x - 8
                    end
                end
            end
            -- Mirem si ha de caure
            local tx1, tx2, ty = ((batman.x+4)//8), ((batman.x+10)//8), ((batman.y+16)//8)
            if (not mapa.isSolid(tx1,ty)) and (not mapa.isSolid(tx2,ty)) then
                batman.state = batman.states.FALL
            end
            -- Mirem si comença a botar
            if (batman.state ~= batman.states.FALL) and (key.down(key.X)) then
                batman.state = batman.states.JUMP
                batman.jump_counter = 0
            end
        end

        if batman.state == batman.states.WALK then
            -- Mirem si comença a caminar
            if key.down(key.RIGHT) then
                batman.state = batman.states.WALK
                batman.flip=false
                local tx, ty = ((batman.x+12)//8), ((batman.y+8)//8)
                if not mapa.isSolid(tx,ty) then batman.x = batman.x + 2 end
            elseif key.down(key.LEFT) then
                batman.state = batman.states.WALK
                batman.flip=true
                local tx, ty = ((batman.x+3)//8), ((batman.y+8)//8)
                if not mapa.isSolid(tx,ty) then batman.x = batman.x - 2 end
            else
                -- Ha parat de caminar
                batman.state = batman.states.IDLE
                batman.frames = {0}
                batman.frame = 1
            end
            -- Mirem si ha de caure
            local tx1, tx2, ty = ((batman.x+4)//8), ((batman.x+10)//8), ((batman.y+16)//8)
            if (not mapa.isSolid(tx1,ty)) and (not mapa.isSolid(tx2,ty)) then
                batman.state = batman.states.FALL
            end
            -- Mirem si comença a botar
            if key.down(key.X) then
                batman.state = batman.states.JUMP
                batman.jump_counter = 0
            end
        end

        if batman.state == batman.states.JUMP then
            batman.y = batman.y - 4
            batman.jump_counter = batman.jump_counter + 1
            if batman.jump_counter == 5 then
                batman.jump_counter = 0
                batman.state = batman.states.FALL
                batman.frames = {4}
                batman.frame = 1
            end
            if key.down(key.RIGHT) then
                batman.flip=false
                local tx, ty = ((batman.x+12)//8), ((batman.y+8)//8)
                if not mapa.isBlock(tx,ty) then batman.x = batman.x + 2 end
            elseif key.down(key.LEFT) then
                batman.flip=true
                local tx, ty = ((batman.x+3)//8), ((batman.y+8)//8)
                if not mapa.isBlock(tx,ty) then batman.x = batman.x - 2 end
            end
        end

        if batman.state == batman.states.FALL then
            if key.down(key.RIGHT) then
                batman.flip=false
                local tx, ty = ((batman.x+12)//8), ((batman.y+8)//8)
                if not mapa.isSolid(tx,ty) then batman.x = batman.x + 2 end
            elseif key.down(key.LEFT) then
                batman.flip=true
                local tx, ty = ((batman.x+3)//8), ((batman.y+8)//8)
                if not mapa.isSolid(tx,ty) then batman.x = batman.x - 2 end
            end

            local tx1, tx2, ty = ((batman.x+4)//8), ((batman.x+10)//8), ((batman.y+16)//8)
            if (batman.ignore_first_tile>0) or ((not mapa.isSolid(tx1,ty)) and (not mapa.isSolid(tx2,ty))) then
                if batman.ignore_first_tile>0 then batman.ignore_first_tile = batman.ignore_first_tile - 1 end
                batman.state = batman.states.FALL
                batman.frames = {4}
                batman.frame = 1
                batman.y = batman.y + 4
            else
                batman.y = (batman.y//8)*8
                batman.state = batman.states.IDLE
                batman.frames = {0}
                batman.frame = 1
            end
        end

        if batman.state == batman.states.STAIRS_IDLE then
            local moving = false
            if key.down(key.DOWN) then
                moving = true
                local tx, ty = ((batman.x+4)//8), ((batman.y+16)//8)
                if (mapa.isStairs(tx,ty)) then
                    if #batman.frames==1 then
                        batman.frames = {8,10,9,10}
                        batman.frame = 1
                    end
                    batman.y = batman.y + 2;
                else
                    batman.state = batman.states.IDLE
                    batman.frames = {0}
                    batman.frame = 1
                end
            elseif key.down(key.UP) then
                moving = true
                local tx, ty = ((batman.x+4)//8), ((batman.y+7)//8)
                if (mapa.isStairs(tx,ty)) then
                    if #batman.frames==1 then
                        batman.frames = {8,10,9,10}
                        batman.frame = 1
                    end
                    batman.y = batman.y - 2;
                else
                    batman.state = batman.states.IDLE
                    batman.frames = {0}
                    batman.frame = 1
                end
            elseif key.down(key.X) then
                batman.state = batman.states.IDLE
                batman.frames = {0}
                batman.frame = 1
            end
            if not moving then
                batman.frames = {10}
                batman.frame = 1
            end
        end
    end,

}