window resize

local math = require('hs.math')
local hyper = {"cmd"}

local function getWindows()
	local win = hs.window.focusedWindow()
	local screen = win:screen()
	return win, screen
end

local function getFrames(win, screen)
	return win:frame(), screen:frame()
end

local function tableHas(set, key)
    return set[key] ~= nil
end

local function roundToThree(x)
	return math.floor(x * 1000 + 0.5) / 1000
end

local function calcNextRatio(win, screen, command)
	local state = {
		[0.5] = 0.333,
		[0.333] = 0.666,
		[0.666] = 0.5
	}
	-- Is it on the left and you're asking to go on the right? i.e opposite side?
	if command == 'right' then
		if win.x == 0 then return 0.5 end -- if it was on the left
	end

	if command == 'left' then
		if win.x == screen.w * 0.5 or
			win.x == screen.w * 0.333 or
			win.x == screen.w * 0.666 then
			return 0.5
		end
	end

	-- calculates the ratio that the screen takes up currently
	local ratio = roundToThree(win.w / screen.w)
	if tableHas(state, ratio) then
		return state[ratio]
	end
	return 0.5
	
end

hs.hotkey.bind(hyper, "left", function()
	local win, screen = getWindows()
	local winframe, screenframe = getFrames(win, screen)
	local nextRatio = calcNextRatio(winframe, screenframe, "left")

	winframe.x = screenframe.x
	winframe.y = screenframe.y
	winframe.w = screenframe.w * nextRatio
	winframe.h = screenframe.h
	win:setFrame(winframe, 0)
end)

hs.hotkey.bind(hyper, "right", function()
	local win, screen = getWindows()
	local winframe, screenframe = getFrames(win, screen)
	local nextRatio = calcNextRatio(winframe, screenframe, "right")

	winframe.x = screenframe.x + (screenframe.w * (1 - nextRatio))
	winframe.y = screenframe.y
	winframe.w = screenframe.w * nextRatio
	winframe.h = screenframe.h
	win:setFrame(winframe, 0)
end)