/ld26-basecode

-- Class: Gamepad

-- This represents a single gamepad connected to the user's computer. This offers the 

-- usual functions to check on the status of buttons; you can also inspect other

-- controls, like analog joysticks, by checking properties like <axes> and <hats>.

-- (Incidentally, a hat is used for things like a digital control pad.) 

--

-- Normally, gamepad buttons are indexed by number. This class also adds virtual buttons

-- named 'left', 'right', 'up', 'down'. This consults the first two analog axes

-- and the first hat of the gamepad (if they exist) to set these.

--

-- A gamepad is only recognized if it is plugged in when LOVE starts up. There's no way

-- to tell if the user has unplugged it after that; it just acts inert. A gamepad object

-- with no connected hardware at startup will exist and respond to calls like <pressed()>,

-- but it will always return false. You can tell it's unplugged because its active property

-- will be false, and its name will always be 'NO DEVICE CONNECTED'.

--

-- Extends:

--		<Sprite>

Gamepad = Sprite:extend

{

	-- Property: number

	-- The index of the gamepad, starting at 1.

	-- Property: name

	-- The name of the gamepad, e.g. "XBox Controller".

	-- Property: numAxes

	-- The number of available axes, e.g. for analog controls.

	-- Property: numBalls

	-- The number of available balls.

	-- Property: numButtons

	-- The number of available buttons.

	-- Property: numHats

	-- The number of available hats, e.g. digital movement controls.

	-- Property: axes

	-- The state of all analog axes on the gamepad, indexed by number.

	-- Values range from -1 to 1, where 0 is completely neutral.

	-- Property: balls

	-- The amount of motion by a each ball on the gamepad, indexed by number.

	-- Not sure what the range of values is here.

	-- Property: hats

	-- The state of each hat on the gamepad, indexed by number. Each one has

	-- one of these values: https://love2d.org/wiki/JoystickConstant

	-- Property: deadZone

	-- Any motion by an analog control (from 0 to 1) less than this value is

	-- ignored when simulating digital controls.

	deadZone = 0.1,

	-- private property: _thisFrame

	-- what keys are pressed this frame

	-- if you are interested in this, use allPressed() instead

	_thisFrame = {},

	-- private property: _lastFrame

	-- what buttons were pressed last frame

	_lastFrame = {},

	new = function (self, obj)

		obj = self:extend(obj)

		assert(type(obj.number) == 'number', 'must set a gamepad number')

		obj.axes = {}

		obj.balls = {}

		obj.hats = {}

		if obj.number <= love.joystick.getNumJoysticks() then

			if not love.joystick.isOpen(obj.number) then love.joystick.open(obj.number) end

			obj.name = love.joystick.getName(obj.number)

			obj.numAxes = love.joystick.getNumAxes(obj.number)

			obj.numBalls = love.joystick.getNumBalls(obj.number)

			obj.numButtons = love.joystick.getNumButtons(obj.number)

			obj.numHats = love.joystick.getNumHats(obj.number)

			-- set initial values for axes and balls

			-- hat values are strings so nil comparisons are safe

			for i = 1, obj.numAxes do

				obj.axes[i] = 0

			end

			for i = 1, obj.numBalls do

				obj.balls[i] = { x = 0, y = 0 }

			end

		else

			obj.name = 'NO DEVICE CONNECTED'

			obj.numAxes = 0

			obj.numBalls = 0

			obj.numButtons = 0

			obj.numHats = 0

		end

		love.joystickpressed = Gamepad._dispatchPress

		love.joystickreleased = Gamepad._dispatchRelease

		if obj.onNew then obj:onNew() end

		return obj

	end,

	-- Method: pressed

	-- Are *any* of the buttons passed held down this frame?

	--

	-- Arguments:

	--		button numbers passed as individual arguments

	--

	-- Returns:

	-- 		boolean

	pressed = function (self, ...)

		local buttons = {...}

		for _, value in pairs(buttons) do

			if self._thisFrame[value] then

				return true

			end

		end

		return false

	end,

	-- Method: justPressed

	-- Are *any* of the buttons passed pressed for the first time this frame?

	--

	-- Arguments:

	--		button numbers passed as individual arguments

	--

	-- Returns:

	-- 		boolean

	justPressed = function (self, ...)

		local buttons = {...}

		for _, value in pairs(buttons) do

			if self._thisFrame[value] and not self._lastFrame[value] then

				return true

			end

		end

		return false

	end,

	-- Method: released

	-- Are *all* of the buttons passed not held down this frame?

	--

	-- Arguments:

	--		button numbers passed as individual arguments

	--

	-- Returns:

	-- 		boolean

	released = function (self, ...)

		local buttons = {...}

		for _, value in pairs(buttons) do

			if self._thisFrame[value] then

				return false

			end

		end

		return true

	end,

	-- Method: justReleased

	-- Are *any* of the buttons passed released after being held last frame?

	--

	-- Arguments:

	--		button numbers passed as individual arguments

	--

	-- Returns:

	-- 		boolean

	justReleased = function (self, ...)

		local buttons = {...}

		for _, value in pairs(buttons) do

			if self._lastFrame[value] and not self._thisFrame[value] then

				return true

			end

		end

		return false

	end,

	-- Method: allPressed

	-- Returns all buttons currently pressed this frame.

	--

	-- Arguments:

	--		none

	--

	-- Returns:

	--		string button descriptions; if nothing is pressed, nil

	allPressed = function (self)

		local result = {}

		for key, value in pairs(self._thisFrame) do

			if value then table.insert(result, key) end

		end

		return unpack(result)

	end,

	-- Method: allJustPressed

	-- Returns all buttons just pressed this frame.

	--

	-- Arguments:

	--		none

	--

	-- Returns:

	--		string button descriptions; if nothing is just pressed, nil

	allJustPressed = function (self)

		local result = {}

		for key, value in pairs(self._thisFrame) do

			if value and not self._lastFrame[key] then table.insert(result, key) end

		end

		return unpack(result)

	end,

	-- Method: allJustReleased

	-- Returns all buttons just released this frame.

	--

	-- Arguments:

	--		none

	--

	-- Returns:

	--		string button descriptions; if nothing is just pressed, nil

	allJustReleased = function (self)

		local result = {}

		for key, value in pairs(self._thisFrame) do

			if not value and self._lastFrame[key] then table.insert(result, key) end

		end

		return unpack(result)

	end,

	buttonPressed = function (self, button)

		self._thisFrame[button] = true

	end,

	buttonReleased = function (self, button)

		self._thisFrame[button] = false

	end,

	endFrame = function (self, elapsed)

		-- move button values to the previous frame

		for key, value in pairs(self._thisFrame) do

			self._lastFrame[key] = value

		end

		-- set values

		for i = 1, self.numAxes do

			self.axes[i] = love.joystick.getAxis(self.number, i)

		end

		for i = 1, self.numBalls do

			self.balls[i].x, self.balls[i].y = love.joystick.getBall(self.number, i)

		end

		for i = 1, self.numHats do

			self.hats[i] = love.joystick.getHat(self.number, i)

		end

		-- simulate digital controls

		self._thisFrame['up'] = false

		self._thisFrame['down'] = false

		self._thisFrame['left'] = false

		self._thisFrame['right'] = false

		if self.numHats > 0 then

			local hat = self.hats[1]

			if hat == 'u' then

				self._thisFrame['up'] = true

			elseif hat == 'd' then

				self._thisFrame['down'] = true

			elseif hat == 'l' then

				self._thisFrame['left'] = true

			elseif hat == 'r' then

				self._thisFrame['right'] = true

			elseif hat == 'lu' then

				self._thisFrame['up'] = true

				self._thisFrame['left'] = true

			elseif hat == 'ru' then

				self._thisFrame['up'] = true

				self._thisFrame['right'] = true

			elseif hat == 'ld' then

				self._thisFrame['down'] = true

				self._thisFrame['left'] = true

			elseif hat == 'rd' then

				self._thisFrame['down'] = true

				self._thisFrame['right'] = true

			end

		end

		if self.numAxes > 1 then

			local xAxis = self.axes[1]

			local yAxis = self.axes[2]

			if math.abs(xAxis) > self.deadZone then

				if xAxis < 0 then

					self._thisFrame['left'] = true

				else

					self._thisFrame['right'] = true

				end

			end

			if math.abs(yAxis) > self.deadZone then

				if yAxis < 0 then

					self._thisFrame['up'] = true

				else

					self._thisFrame['down'] = true

				end

			end

		end

		Sprite.endFrame(self)

	end,

	-- private method: _dispatchPress

	-- receives a Love joystickpressed callback and hands it off

	-- to the appropriate gamepad.

	_dispatchPress = function (number, button)

		if the.gamepads[number] then

			the.gamepads[number]:buttonPressed(button)

		end

	end,

	-- private method: _dispatchRelease

	-- receives a Love joystickreleased callback and hands it off

	-- to the appropriate gamepad.

	_dispatchRelease = function (number, button)

		if the.gamepads[number] then

			the.gamepads[number]:buttonReleased(button)

		end

	end

}