rednet.open("back")

buttons = {}

local cur_power_gen = 0
local target_power = 5000 -- RF/Tick
local control_rod_level = 50
local reactor_enabled = false

local mw, mh = term.getSize()

function drawBoxWithCenteredText(x,y,w,h,text,color)
	local ox,oy = term.getCursorPos()
	local bgColor = term.getBackgroundColor()

	term.setBackgroundColor(color)
	for cy=1,h,1 do
		for cx=1,w,1 do
			term.setCursorPos(x+cx,y+cy)
			term.write(" ")
		end
	end

	local cx = math.floor(w / 2 + x - string.len(text) / 2 + 1)
	local cy = math.floor(h / 2 + y + 1)

	term.setCursorPos(cx, cy)
	term.write(text)

	term.setBackgroundColor(bgColor)
	term.setCursorPos(ox, oy)
end

function clamp(val, min, max) 
	if val > max then
		return max
	elseif val < min then
		return min
	else
		return val
	end
end

function drawBar(x, y, size, perc)
	local bgColor = term.getBackgroundColor()
	local ox, oy = term.getCursorPos()

	term.setCursorPos(x, y)
	term.setBackgroundColor(colors.green)

	local percGreen = clamp(math.floor(perc * size), 0, size)
	local percGray = clamp(size - percGreen, 0, size - percGreen)
	if percGray < 0 then
		percGray = 0
	end

	for i = percGreen,1,-1 do
		term.write(" ")
	end
	term.setBackgroundColor(colors.lightGray)
	for i = percGray,1,-1 do
		term.write(" ")
	end

	term.setBackgroundColor(bgColor)
	term.setCursorPos(ox, oy)
end

function getControlRodDiff(RFDiff)
	if RFDiff > 10000 then
		return 5
	elseif RFDiff > 5000 then
		return 3
	elseif RFDiff > 1000 then
		return 1
	elseif RFDiff > 500 then
		return 0.5
	elseif RFDiff > 100 then
		return 0.1
	else
		return 0.05
	end
end

function formatRF(rf)
	if rf >= 1000000 then
		return round(rf/1000000, 2) .. " MiRF"
	elseif rf >= 1000 then
		return round(rf/1000, 2) .. " KiRF"
	else 
		return math.floor(rf) .. " RF"
	end
end

function round(num, numDecimalPlaces)
  	local mult = 10^(numDecimalPlaces or 0)
  	return math.floor(num * mult + 0.5) / mult
end

function renderButtons()
	for i = 1, #buttons do
		local button = buttons[i]
		if not reactor_enabled then
			if button.drod then
				drawBoxWithCenteredText(button.x,button.y,button.w,button.h,button.text,button.color)
			end
		else
			drawBoxWithCenteredText(button.x,button.y,button.w,button.h,button.text,button.color)
		end
	end
end

function addButton(x,y,w,h,text,color,doRenderOnDisable, executor)
	local button = {
		x = x,
		y = y,
		w = w,
		h = h,
		text = text,
		color = color,
		drod = doRenderOnDisable,
		executor = executor
	}
	buttons[#buttons+1] = button
end

function inBounds(n, min, max)
	return n <= max and n >= min
end

function sendBTNCommand(btn)
	sendCommand({button = btn.text})
end

addButton(1,mh - 4,11,3,"SHUT DOWN",colours.red, true, sendBTNCommand)
addButton(14,mh - 4,11,3,"START",colours.green, true, sendBTNCommand)

addButton(1, 9, 3, 1, "-10", colours.red, false, sendBTNCommand)
addButton(5, 9, 4, 1, "-100", colours.red, false, sendBTNCommand)
addButton(10, 9, 5, 1, "-1000", colours.red, false, sendBTNCommand)

addButton(1, 11, 3, 1, "+10", colours.green, false, sendBTNCommand)
addButton(5, 11, 4, 1, "+100", colours.green, false, sendBTNCommand)
addButton(10, 11, 5, 1, "+1000", colours.green, false, sendBTNCommand)

function sendCommand(command)
	rednet.send(0, textutils.serialize(command), "reactor_control")
	local id, object = rednet.receive("reactor_response")
	return textutils.unserialize(object)
end

function getReactorStatus()
	return sendCommand("_QUERY_")
end

term.clear()

function render()
	while true do
		local reactor_status = getReactorStatus()

		cur_power_gen = reactor_status.cur_power_gen
		reactor_enabled = reactor_status.reactor_enabled
		target_power = reactor_status.target_power
		control_rod_level = reactor_status.control_rod_level

		if cur_power_gen ~= 0 and reactor_enabled then
			term.setCursorPos(1,1)
			term.write("Control Rod Level: ")
			drawBar(1,2,20,control_rod_level/100)
			term.setCursorPos(22,2)
			term.write(math.floor(control_rod_level) .. "\%  ")

			term.setCursorPos(1,4)
			term.write("Power Generation: ")
			drawBar(1,5,13,cur_power_gen/target_power)
			term.setCursorPos(15,5)
			term.write(formatRF(cur_power_gen) .. "/t    ")

			term.setCursorPos(1,7)
			term.write("Target power generation: ")
			term.setCursorPos(2,8)
			term.clearLine()
			term.setBackgroundColor(colors.blue)
			term.write(formatRF(target_power) .. "/t")
			term.setBackgroundColor(colors.black)
		end

		if not reactor_enabled then
			term.clear()
			term.setCursorPos(2,2)
			term.write("Reactor is offline")
		end

		renderButtons()
		sleep(0.1)
	end
end

function pullEvents()
	while true do
		event, button, x, y = os.pullEvent("mouse_click")
		for i=1, #buttons do
			local button = buttons[i]
			if inBounds(x, button.x, button.x + button.w) and inBounds(y, button.y, button.y + button.h) then
				button.executor(button)
				break
			end
		end
	end
end

parallel.waitForAny(pullEvents, render)