function love.load()
    love.resize(love.graphics.getDimensions())

    gGuesses, gCurrentGuess = {}, 1
    for i = 1, 10 do
        gGuesses[i] = { digits = {} }
    end
end

function love.resize(w, h)
    gWidth, gHeight = w, h
end

function drawDigit(digit, x, y)
    love.graphics.line(x, y, x + 10, y)
    if digit then
        love.graphics.print(digit, x + 1, y - 15)
    end
end

function drawSingleGuess(guess, x, y)
    for i = 0, 3 do
        drawDigit(guess.digits[i + 1], x + i * (10 + 6), y)
    end
    if guess.dots then
        for i = 1, 4 do
                if guess.dots[i] == 0 then
                love.graphics.circle("fill", x + 70 + i * 14, y - 4, 4)
            elseif guess.dots[i] == 1 then
                love.graphics.circle("line", x + 70 + i * 14, y - 4, 6)
            else
                love.graphics.circle("fill", x + 70 + i * 14, y - 4, 6)
            end
        end
    end
end

function love.draw()
    for i = 0, 9 do
        drawSingleGuess(
            gGuesses[gCurrentGuess],
            (gWidth - (10 * 4 + 6 * 3)) / 2,
            (gHeight - (10 * 20)) / 2 + i * 20
        )
    end
end

function love.keypressed(key)
        if key == "escape"      then
        love.event.quit()
    elseif key == "backspace"   then
        gGuesses[gCurrentGuess].digits = {}
    elseif key == "return"      then
        if #gCurrentDigits ~= 4 then
            return
        end

        gCurrentGuess = gCurrentGuess + 1
    elseif string.match("123456789", key) then
        if #gCurrentDigits == 4 then
            return
        end

        for i = 1, #gCurrentDigits do
            if gCurrentDigits[i] == key then
                return
            end
        end

        table.insert(gCurrentDigits, key)
    end
end