SpriteReader = {}

function SpriteReader:load(data)
    attr = {version = 0, numberOfSprites = 0, posByte = 1, data = data:read("*a")}
    return setmetatable(attr, {__index = self})
end

function SpriteReader:getRanges(byte, signed)
    local min, max = 0, 0
    for var = byte, 1, -1 do
        max = max +(2 ^ (8 * var))
    end
    if(signed)then
        min, max = max/2, -max/2
    end
    return min, not signed and (max - 1) or max
end

function SpriteReader:readBytes(byte, signed)
    local min, _ = self:getRanges(byte, signed)
    local value = self:nextByte()
    for var = 2, byte do
        value = value + (self:nextByte() ^ 2)
    end
    return value
end

function SpriteReader:nextByte()
    local byte = self.data:byte(self.posByte)
    self.posByte = self.posByte + 1
    return tonumber(byte)
end

function SpriteReader:getUint64()
    return self:readBytes(8, false)
end

function SpriteReader:getInt64()
    return self:readBytes(8, true)
end

function SpriteReader:getUint32()
    return self:readBytes(4, false)
end

function SpriteReader:getInt32()
    return self:readBytes(4, true)
end

function SpriteReader:getUint16()
    return self:readBytes(2, false)
end

function SpriteReader:getInt16()
    return self:readBytes(2, true)
end

function SpriteReader:getUint8()
    return self:readBytes(1, false)
end

function SpriteReader:getInt8()
    return self:readBytes(1, true)
end

function SpriteReader:closeData()
    return self.data:close()
end

    local file = io.open("./ka.spr", "rb")
    reader = SpriteReader:load(file)
    reader.version = reader:getUint32()
    reader.numberOfSprites = reader:getUint16()
    io.write("Version: ",reader.version,"\nNumber Of Sprites: ", reader.numberOfSprites)