local input = require((...):match("^(.-%.)backend").."input")

local loaded, signal = pcall(require, (...):match("^(.-)input").."signal")
if not loaded then signal = nil end

local gfx = require("ctr.gfx")
local hid = require("ctr.hid")

local keys = {}
local touchX, touchY, dTouchX, dTouchY

local oUpdate = input.update
input.update = function(dt)
	hid.read()

	keys = hid.keys()

	local nTouchX, nTouchY = hid.touch()
	dTouchX, dTouchY = nTouchX - touchX, nTouchY - touchY
	touchX, touchY = nTouchX, nTouchY

	oUpdate(dt)
end

input.buttonDetector = function(...)
	local ret = {}
	for _,id in ipairs({...}) do
		-- Keys
		if id:match("^key%.") then
			local key = id:match("^key%.(.+)$")
			table.insert(ret, function()
				return keys.held[key]
			end)
		else
			error("Unknown button identifier: "..id)
		end
	end
	return table.unpack(ret)
end

input.axisDetector = function(...)
	local ret = {}
	for _,id in ipairs({...}) do
		-- Binary axis
		if id:match(".+%,.+") then
			local d1, d2 = input.buttonDetector(id:match("^(.+)%,(.+)$"))
			table.insert(ret, function()
				local b1, b2 = d1(), d2()
				if b1 and b2 then return 0
				elseif b1 then return -1
				elseif b2 then return 1
				else return 0 end
			end)
		-- Touch movement
		elseif id:match("^touch%.move%.") then
			local axis, threshold = id:match("^touch%.move%.(.+)%%(.+)$")
			if not axis then axis = id:match("^touch%.move%.(.+)$") end -- no threshold (=0)
			threshold = tonumber(threshold) or 0
			table.insert(ret, function()
				local val, raw, max
				if axis == "x" then
					raw, max = dTouchX, gfx.BOTTOM_WIDTH
				elseif axis == "y" then
					raw, max = dTouchY, gfx.BOTTOM_HEIGHT
				end
				val = raw / max
				return math.abs(val) > math.abs(threshold) and val or 0, raw, max
			end)
		-- Touch position
		elseif id:match("^touch%.position%.") then
			local axis, threshold = id:match("^touch%.position%.(.+)%%(.+)$")
			if not axis then axis = id:match("^touch%.position%.(.+)$") end -- no threshold (=0)
			threshold = tonumber(threshold) or 0
			table.insert(ret, function()
				local val, raw, max
				if axis == "x" then
					max = gfx.BOTTOM_WIDTH / 2 -- /2 because x=0,y=0 is the center of the screen (an axis value is in [-1,1])
					raw = touchX - max
				elseif axis == "y" then
					max = gfx.BOTTOM_HEIGHT / 2
					raw = touchY - max
				end
				val = raw / max
				return math.abs(val) > math.abs(threshold) and val or 0, raw, max
			end)
		-- Circle pad axis
		elseif id:match("^circle%.") then
			local axis, threshold = id:match("^circle%.(.+)%%(.+)$")
			if not axis then axis = id:match("^circle%.(.+)$") end -- no threshold (=0)
			threshold = tonumber(threshold) or 0
			table.insert(ret, function()
				local x, y = hid.circle()
				local val, raw, max = 0, 0, 156
				if axis == "x" then raw = x
				elseif axis == "y" then raw = y end
				val = raw / max
				return math.abs(val) > math.abs(threshold) and val or 0, raw, max
			end)
		-- C-Stick axis
		elseif id:match("^cstick%.") then
			local axis, threshold = id:match("^cstick%.(.+)%%(.+)$")
			if not axis then axis = id:match("^cstick%.(.+)$") end -- no threshold (=0)
			threshold = tonumber(threshold) or 0
			table.insert(ret, function()
				local x, y = hid.cstick()
				local val, raw, max = 0, 0, 146
				if axis == "x" then raw = x
				elseif axis == "y" then raw = y end
				val = raw / max
				return math.abs(val) > math.abs(threshold) and val or 0, raw, max
			end)
		-- Accelerometer axis
		elseif id:match("^accel%.") then
			local axis, threshold = id:match("^accel%.(.+)%%(.+)$")
			if not axis then axis = id:match("^accel%.(.+)$") end -- no threshold (=0)
			threshold = tonumber(threshold) or 0
			table.insert(ret, function()
				local x, y, z = hid.accel()
				local val, raw, max = 0, 0, 32768 -- no idea actually, but it's a s16
				if axis == "x" then raw = x
				elseif axis == "y" then raw = y
				elseif axis == "z" then raw = z end
				val = raw / max
				return math.abs(val) > math.abs(threshold) and val or 0, raw, max
			end)
		-- Gyroscope axis
		elseif id:match("^gyro%.") then
			local axis, threshold = id:match("^gyro%.(.+)%%(.+)$")
			if not axis then axis = id:match("^gyro%.(.+)$") end -- no threshold (=0)
			threshold = tonumber(threshold) or 0
			table.insert(ret, function()
				local roll, pitch, yaw = hid.gyro()
				local val, raw, max = 0, 0, 32768 -- no idea actually, but it's a s16
				if axis == "roll" then raw = roll
				elseif axis == "pitch" then raw = pitch
				elseif axis == "yaw" then raw = yaw end
				val = raw / max
				return math.abs(val) > math.abs(threshold) and val or 0, raw, max
			end)
		else
			error("Unknown axis identifier: "..id)
		end
	end
	return table.unpack(ret)
end

input.buttonsInUse = function(threshold)
	local r = {}
	for key, held in pairs(keys.held) do
		if held then table.insert(r, "key."..key) end
	end
	return r
end

input.axesInUse = function(threshold)
	local r = {}
	threshold = threshold or 0.5

	if math.abs(touchX) / gfx.BOTTOM_WIDTH > threshold then table.insert(r, "touch.position.x%"..threshold) end
	if math.abs(touchY) / gfx.BOTTOM_HEIGHT > threshold then table.insert(r, "touch.position.y%"..threshold) end

	if math.abs(dTouchX) / gfx.BOTTOM_WIDTH > threshold then table.insert(r, "touch.move.x%"..threshold) end
	if math.abs(dTouchY) / gfx.BOTTOM_HEIGHT > threshold then table.insert(r, "touch.move.y%"..threshold) end

	local circleX, circleY = hid.circle()
	if math.abs(circleX) / 156 > threshold then table.insert(r, "circle.x%"..threshold) end
	if math.abs(circleY) / 156 > threshold then table.insert(r, "circle.y%"..threshold) end

	if ctr.apt.isNew3DS() then
		local cstickX, cstickY = hid.cstick()
		if math.abs(cstickY) / 146 > threshold then table.insert(r, "cstick.y%"..threshold) end
		if math.abs(cstickX) / 146 > threshold then table.insert(r, "cstick.x%"..threshold) end
	end

	local accelX, accelY, accelZ = hid.accel()
	if math.abs(accelX) / 32768 > threshold then table.insert(r, "accel.x%"..threshold) end
	if math.abs(accelY) / 32768 > threshold then table.insert(r, "accel.y%"..threshold) end
	if math.abs(accelZ) / 32768 > threshold then table.insert(r, "accel.z%"..threshold) end

	-- no gyro, because it is always in use

	return r
end

input.buttonName = function(...)
	local ret = {}
	for _,id in ipairs({...}) do
		-- Key
		if id:match("^key%.") then
			local key = id:match("^key%.(.+)$")
			table.insert(ret, key:sub(1,1):upper()..key:sub(2).." key")
		else
			table.insert(ret, id)
		end
	end
	return table.unpack(ret)
end

input.axisName = function(...)
	local ret = {}
	for _,id in ipairs({...}) do
		-- Binary axis
		if id:match(".+%,.+") then
			local b1, b2 = input.buttonName(id:match("^(.+)%,(.+)$"))
			table.insert(ret, b1.." / "..b2)
		-- Touch movement
		elseif id:match("^touch%.move%.") then
			local axis, threshold = id:match("^touch%.move%.(.+)%%(.+)$")
			if not axis then axis = id:match("^touch%.move%.(.+)$") end -- no threshold (=0)
			threshold = tonumber(threshold) or 0
			table.insert(ret, ("Touch %s movement (threshold %s%%)"):format(axis, math.abs(threshold*100)))
		-- Touch position
		elseif id:match("^touch%.position%.") then
			local axis, threshold = id:match("^touch%.position%.(.+)%%(.+)$")
			if not axis then axis = id:match("^touch%.position%.(.+)$") end -- no threshold (=0)
			threshold = tonumber(threshold) or 0
			table.insert(ret, ("Touch %s position (threshold %s%%)"):format(axis, math.abs(threshold*100)))
		-- Circle pad axis
		elseif id:match("^circle%.") then
			local axis, threshold = id:match("^circle%.(.+)%%(.+)$")
			if not axis then axis = id:match("^circle%.(.+)$") end -- no threshold (=0)
			threshold = tonumber(threshold) or 0
			if axis == "x" then
				table.insert(ret, ("Circle pad horizontal axis (deadzone %s%%)"):format(math.abs(threshold*100)))
			elseif axis == "y" then
				table.insert(ret, ("Circle pad vertical axis (deadzone %s%%)"):format(math.abs(threshold*100)))
			else
				table.insert(ret, ("Circle pad %s axis (deadzone %s%%)"):format(axis, math.abs(threshold*100)))
			end
		-- C-Stick axis
		elseif id:match("^cstick%.") then
			local axis, threshold = id:match("^cstick%.(.+)%%(.+)$")
			if not axis then axis = id:match("^cstick%.(.+)$") end -- no threshold (=0)
			threshold = tonumber(threshold) or 0
			if axis == "x" then
				table.insert(ret, ("C-Stick horizontal axis (deadzone %s%%)"):format(math.abs(threshold*100)))
			elseif axis == "y" then
				table.insert(ret, ("C-Stick vertical axis (deadzone %s%%)"):format(math.abs(threshold*100)))
			else
				table.insert(ret, ("C-Stick %s axis (deadzone %s%%)"):format(axis, math.abs(threshold*100)))
			end
		-- Accelerometer axis
		elseif id:match("^accel%.") then
			local axis, threshold = id:match("^accel%.(.+)%%(.+)$")
			if not axis then axis = id:match("^accel%.(.+)$") end -- no threshold (=0)
			threshold = tonumber(threshold) or 0
			table.insert(ret, ("Accelerometer %s axis (deadzone %s%%)"):format(axis, math.abs(threshold*100)))
		-- Gyroscope axis
		elseif id:match("^gyro%.") then
			local axis, threshold = id:match("^gyro%.(.+)%%(.+)$")
			if not axis then axis = id:match("^gyro%.(.+)$") end -- no threshold (=0)
			threshold = tonumber(threshold) or 0
			table.insert(ret, ("Gyroscope %s axis (deadzone %s%%)"):format(axis, math.abs(threshold*100)))
		else
			table.insert(ret, id)
		end
	end
	return table.unpack(ret)
end

-- Size
input.screenWidth, input.screenHeight =  gfx.TOP_WIDTH, gfx.TOP_HEIGHT

-- Defaults
input.default.pointer:bind(
	{ "absolute", "key.left,key.right", "key.up,key.down" },
	{ "absolute", "circle.x", "circle.y" }
)
input.default.confirm:bind("key.a")
input.default.cancel:bind("key.b")

--- Register signals
if signal then
	signal.event:replace("update", oUpdate, input.update)
end

return input