local lives = 3

local mon = term

local timerLength = 0.25
local ballX, ballY
local paddleX = 25
local paddleY = 19
local paddleWidth = 7
local paddleWidth2 = 3
local paddleString = "       "
local ballVelX, ballVelY
local boardWidth = 51
local boardHeight = 19
local boardColor = colors.black
local ballColor = colors.white
local paddleColor = colors.gray

local blockColor = {colors.red, colors.blue, colors.green}
local numBlockColors = 3

local boardArray = {}

local function breakBlock(px, py)
	minX = px
	color = boardArray[px][py]
	while boardArray[minX - 1][py] == color do minX = minX - 1 end
	mon.setBackgroundColor(boardColor)
	mon.setCursorPos(minX, py)
	mon.write("     ")
	maxX = minX + 4
	for x = minX, maxX do
		boardArray[x][py] = boardColor
	end
end

local function main()

	local event, param1, param2, xPos, yPos
	local oldX, oldY, newX, newY


	ballX = boardWidth / 2
	ballY = paddleY - 1
	ballVelX = math.random(-1, 1)
	ballVelY = -1
	paddleX = boardWidth / 2

	timer1 = os.startTimer(timerLength)
	while lives > -1 do
		event, param1, xPos, yPos = os.pullEvent()

		if event == "timer" and param1 == timer1 then
			oldX = math.floor(ballX)
			oldY = math.floor(ballY)
			repeat
				bounced = false
				newX = math.floor(ballX + ballVelX)
				newY = math.floor(ballY + ballVelY)
				if newX < 1 then
					ballVelX = ballVelX * -1
					bounced = true
				end
				if newX > boardWidth then
					ballVelX = ballVelX * -1
					bounced = true
				end
				if newY < 1 then
					ballVelY = ballVelY * -1
					bounced = true
				end
				if newY == paddleY and math.abs(newX - paddleX) <= paddleWidth2 then
					ballVelY = ballVelY * -1
					bounced = true
				end
				if boardArray[oldX][newY] ~= boardArray then
					breakBlock(oldX, newY)
					ballVelY = ballVelY * -1
					bounced = true
				end
				if boardArray[newX][oldY] ~= boardArray then
					breakBlock(oldX, newY)
					ballVelY = ballVelY * -1
					bounced = true
				end
				if newY > boardHeight then
					lives = lives - 1
					mon.setCursorPos(ballX, ballY)
					mon.setBackgroundColor(boardColor)
					mon.write(" ")
					ballX = paddleX
					ballY = paddleY - 1
					ballVelX = math.random(-1, 1)
					ballVelY = -1
					mon.setCursorPos(ballX, ballY)
					mon.setBackgroundColor(ballColor)
					mon.write(" ")
				end
			until not bounced

			mon.setCursorPos(oldX, oldY)
			mon.setBackgroundColor(boardColor)
			mon.write(" ")
			ballX = ballX + ballVelX
			ballY = ballY + ballVelY
			mon.setCursorPos(newX, newY)
			mon.setBackgroundColor(ballColor)
			mon.write(" ")

			timer1 = os.startTimer(timerLength)
		end

		if event == "mouse_drag" or event == "mouse_click" then
			mon.setCursorPos(paddleX - paddleWidth2, paddleY)
			mon.setBackgroundColor(boardColor)
			mon.write(paddleString)
			paddleX = xPos
			if paddleX - paddleWidth2 < 1 then paddleX = paddleWidth2 + 1 end
			if paddleX + paddleWidth2 > boardWidth then paddleX = boardWidth - paddleWidth2 end
			mon.setCursorPos(paddleX - paddleWidth2, paddleY)
			mon.setBackgroundColor(paddleColor)
			mon.write(paddleString)
		end

		if event == "key" then
			if param1 == 203 then --left
				mon.setCursorPos(paddleX - paddleWidth2, paddleY)
				mon.setBackgroundColor(boardColor)
				mon.write(paddleString)
				paddleX = paddleX - 1
				if paddleX - paddleWidth2 < 1 then paddleX = paddleWidth2 + 1 end
				mon.setCursorPos(paddleX - paddleWidth2, paddleY)
				mon.setBackgroundColor(paddleColor)
				mon.write(paddleString)
			elseif param1 == 205 then --right
				mon.setCursorPos(paddleX - paddleWidth2, paddleY)
				mon.setBackgroundColor(boardColor)
				mon.write(paddleString)
				paddleX = paddleX + 1
				if paddleX + paddleWidth2 > boardWidth then paddleX = boardWidth - paddleWidth2 end
				mon.setCursorPos(paddleX - paddleWidth2, paddleY)
				mon.setBackgroundColor(paddleColor)
				mon.write(paddleString)
			elseif param1 == 28 then --enter
				term.setBackgroundColor(colors.black)
				term.setCursorPos(1, 1)
				term.write("Paused")

				repeat
					event, param = os.pullEvent()
				until event == "key" and param == 28

				term.setCursorPos(1, 1)
				term.write("      ")
				timer1 = os.startTimer(timerLength)
			end
		end
	end
end

local function board1()
	local color, prevColor = boardColor
	for y = 1, 3 do
		for x = 1, boardWidth do
			boardArray[x][y] = boardColor
		end
	end
	for y = 4, 10 do
		for x = 1, boardWidth, 5 do
			repeat
				color = blockColor[math.floor(math.random(1, numBlockColors + 0.999))]
			until color ~= prevColor
			for x2 = x, x + 4 do
				boardArray[x][y] = color
			end
		end
	end
	for y = 11, boardHeight do
		for x = 1, boardWidth do
			boardArray[x][y] = boardColor
		end
	end
end

local function drawBoard()
	for y = 1, boardHeight do
		mon.setCursorPos(1, y)
		for x = 1, boardWidth do
			mon.setBackgroundColor(boardArray[x][y])
			mon.write(" ")
		end
	end
end

for x = 1, boardWidth do
	boardArray[x] = {}
end


board1()
drawBoard()
main()