colorRGB = {
    {r = 221, g = 221, b = 221, code = "0"},
    {r = 219, g = 125, b = 62, code = "1"},
    {r = 179, g = 80, b = 188, code = "2"},
    {r = 107, g = 138, b = 201, code = "3"},
    {r = 177, g = 166, b = 39, code = "4"},
    {r = 65, g = 174, b = 56, code = "5"},
    {r = 208, g = 132, b = 153, code = "6"},
    {r = 64, g = 64, b = 64, code = "7"},
    {r = 154, g = 161, b = 161, code = "8"},
    {r = 46, g = 110, b = 137, code = "9"},
    {r = 126, g = 61, b = 181, code = "a"},
    {r = 46, g = 56, b = 141, code = "b"},
    {r = 79, g = 50, b = 31, code = "c"},
    {r = 53, g = 70, b = 27, code = "d"},
    {r = 150, g = 52, b = 48, code = "e"},
    {r = 25, g = 22, b = 22, code = "f"}
}

function readWORD(str, offset)
    local loByte = str:byte(offset)
    local hiByte = str:byte(offset + 1)
    return hiByte * 256 + loByte
end

function readDWORD(str, offset)
    local loWord = readWORD(str, offset)
    local hiWord = readWORD(str, offset + 2)
    return hiWord * 65536 + loWord
end

function get4BitColor(r, g, b)
    for k, v in ipairs(colorRGB) do
        -- print(r .. "/" .. v.r .. " " .. g .. "/" .. v.g .. " " .. b .. "/" .. v.b)

        local lookVel = 10

        if r > v.r - lookVel and r < v.r + lookVel and g > v.g - lookVel and g < v.g + lookVel and b > v.b - lookVel and b < v.b + lookVel then
            return v.code
        end
    end

    return " "
end

function loadBitmap(path)
    local pixels = {}

    local f = assert(io.open(path, "rb"))
    local bytecode = ""
    local byte = f:read()

    while byte ~= nil do
        bytecode = bytecode .. string.char(byte)
        byte = f:read()
    end

    f:close()

    -- Parse BITMAPFILEHEADER
    local offset = 1
    local bfType = readWORD(bytecode, offset)
    if(bfType ~= 0x4D42) then
        print("Not a bitmap file (Invalid BMP magic value)")
        error()
    end
    local offBits = readWORD(bytecode, offset + 10)

    -- Parse BITMAPINFOHEADER
    offset = 15; -- BITMAPFILEHEADER is 14 bytes long
    local width = readDWORD(bytecode, offset + 4)
    local height = readDWORD(bytecode, offset + 8)
    local bitCount = readWORD(bytecode, offset + 14)
    local compression = readDWORD(bytecode, offset + 16)

    if(bitCount ~= 24) then
        print("Only 24-bit bitmaps supported (Is " .. bitCount .. "bpp)")
        error()
    end

    if(compression ~= 0) then
        print("Only uncompressed bitmaps supported (Compression type is " .. compression .. ")")
        error()
    end

    print("Found width " .. width .. "*" .. height)

    -- Parse image
    for y = height - 1, 0, -1 do
        offset = offBits + (width * bitCount / 8) * y + 1

        for x = 1, width do
            if type(pixels[x]) ~= "table" then
                pixels[x] = {}
            end

            local b = bytecode:byte(offset)
            local g = bytecode:byte(offset + 1)
            local r = bytecode:byte(offset + 2)
            offset = offset + 3

            -- print("RGB: " .. r .. " " .. g .. " " .. b)

            pixels[x][height - y] = get4BitColor(r, g, b)
        end
    end

    -- Generate the image
    local tmpF = io.open("_tmp.temp", "w")

    for y = 1, height do
        for x = 1, width do
            tmpF:write(pixels[x][y])
        end

        tmpF:write("\n")
    end

    tmpF:close()

    if paintutils then
        local img = paintutils.loadImage("_tmp.temp")
        fs.delete("_tmp.temp")

        return img
    end
end