class WACOM_POINTER

create {XINPUT_IVY}
	make, make_self_test

feature {}
	make(a_xinput_ivy: XINPUT_IVY) is
		require
			a_xinput_ivy /= Void
		do
			xinput_ivy := a_xinput_ivy
			prediction_time := 25
		end

	make_self_test is
		local
			angle: REAL
			x, y: REAL
			mc: MATH_CONSTANTS
			i: INTEGER
		do
			from
				angle := 80
				prediction_time := 10
			until
				i > 36
			loop
				x := (angle * mc.Pi / 180).cos * 1000
				y := (angle * mc.Pi / 180).sin * 1000
				if i > 2 then
					--io.put_string(once "Real position: x=")
					io.put_real(x)
					--io.put_string(once ", y=")
					io.put_character(' ')
					io.put_real(y)
					io.put_new_line
				end
				update_predicted_position(x, y, angle)
				if i >= 2 then
					--io.put_string(once "Predicted position: x=")
					io.put_real(predicted_x)
					--io.put_string(once ", y=")
					io.put_character(' ')
					io.put_real(predicted_y)
					io.put_character(' ')
					--io.put_new_line
				end
				angle := angle + prediction_time
				i := i + 1
			end
		end
		
	xinput_ivy: XINPUT_IVY

	x_offset, y_offset: INTEGER

	prediction_time: REAL

	ignore_rate, ignored_counter: INTEGER

	pointer_message_header, button_message_header: STRING

	old_presure: INTEGER

	type_to_name(type_id: INTEGER): STRING is
		do
			inspect type_id
			when 2066 then Result := once "pen_2066" -- 0x812
			when 2049 then Result := once "pen_2049" -- 0x801
				-- 0x012
			when 2082 then Result := once "pen_2082" -- 0x822
				-- 0x842
				-- 0x852
			when 2083 then Result := once "grip_pen_2083" -- 0x823
			when 2067 then Result := once "classic_pen_2067" -- 0x813
			when 2181 then Result := once "marker_pen_2181" -- 0x885
				-- 0x022
			when 2098 then Result := once "stroke_pen_2098" -- 0x832
				-- 0x032
			when 3346 then Result := once "airbrush_3346" -- 0xd12
				-- 0x912
				-- 0x112
			when 2323 then Result := once "airbrush_2323" -- 0x913
			when 2090 then Result := once "eraser_2090" -- 0x82a
				-- 0x85a
				-- 0x91a
				-- 0xd1a
				-- 0x0fa
			when 2091 then Result := once "grip_pen_eraser_2091" -- 0x82b
			when 2075 then Result := once "classic_pen_eraser_2075" -- 0x81b
			when 2331 then Result := once "airbrush_eraser_2331" -- 0x91b
			else
				Result := once ""
				Result.clear_count
				type_id.append_in(Result)
			end
		end
	
feature {XINPUT_IVY}
	set_x_offset(offset: INTEGER) is
		do
			x_offset := offset
		end
	
	set_y_offset(offset: INTEGER) is
		do
			y_offset := offset
		end

	set_prediction(milliseconds: REAL) is
		do
			prediction_time := milliseconds
		end

	set_ignore_rate(n: INTEGER) is
		do
			ignore_rate := n
		end

	set_message_header(header: STRING) is
		local
			history_size: INTEGER
		do
			pointer_message_header := "pointer"
			pointer_message_header.append(header)
			button_message_header := "button"
			button_message_header.append(header)
			history_size := 1
			create x_history.make(0, history_size)
			create y_history.make(0, history_size)
			create time_history.make(0, history_size)
		end

	device_to_screen_x(x: INTEGER): INTEGER is
		do
			Result := (x / 86400 * 1600 + x_offset).force_to_integer_32 -- **** geometrie paramétrable
		end

	device_to_screen_y(y: INTEGER): INTEGER is
		do
			Result := (y / 65000 * 1200 + y_offset).force_to_integer_32 -- **** geometrie paramétrable
		end

	x_history, y_history, time_history: RING_ARRAY[INTEGER]

	mean(history: RING_ARRAY[INTEGER]): REAL is
		require
			history.count > 0
		local
			sum: INTEGER_64
			i: INTEGER
		do
			from
				i := history.lower
			until
				i > history.upper
			loop
				sum := sum + history.item(i)
				i := i + 1
			end
			Result := sum / history.count
		end
			
	move(pointer: X_INPUT_DEVICE) is
		local
			x, y, presure: INTEGER
			t3: REAL_64
			message: STRING
		do
			x := pointer.motion_axis_data(1) 
			y := pointer.motion_axis_data(2)
			--update_predicted_position(x, y, pointer.event_time)
			x_history.remove_first
			x_history.add_last(x)
			y_history.remove_first
			y_history.add_last(y)
			time_history.remove_first
			time_history.add_last(pointer.event_time)
			t3 := mean(time_history)
			if t3 /= t2 then
				update_predicted_position(mean(x_history), mean(y_history), t3)
			end
			presure := pointer.motion_axis_data(3)
			if ignored_counter < ignore_rate and then ((old_presure = 0) = (presure = 0)) then
				ignored_counter := ignored_counter + 1
			else
				ignored_counter := 0
				message := once ""
				message.copy(pointer_message_header)				
				print_data_in(message, x, y, presure, pointer.motion_axis_data(4),
								  pointer.motion_axis_data(5),
								  pointer.motion_axis_data(6), pointer.event_time,
								  once "unchanged")
				xinput_ivy.ivy.send_message(message)
			end
			old_presure := presure
		end


	print_data_in(message: STRING; x, y, presure, v4, v5, v6, time: INTEGER; proximity_description: STRING) is
		do
				message.append(once " x=")
				device_to_screen_x(x).append_in(message)
				message.append(once " y=")
				device_to_screen_y(y).append_in(message)
				message.append(once " presure=")
				presure.append_in(message)
				message.append(once " tilt_x=")
				v4.low_16.append_in(message)
				message.append(once " tilt_y=")
				v5.low_16.append_in(message)
				message.append(once " wheel=")
				v6.low_16.append_in(message)
				message.append(once " predicted_x=")
				device_to_screen_x(predicted_x).append_in(message)
				message.append(once " predicted_y=")
				device_to_screen_y(predicted_y).append_in(message)
				message.append(once " type=")
				message.append(type_to_name(v4.high_16))
				message.append(once " serial_number=")
				(v5.high_16.to_integer_32 |<< 16).bit_or(v6.high_16).append_in(message)
				message.append(once " time=")
				time.append_in(message)
 				message.append(once " hires_x=")
 				(x/86400).append_in(message) -- **** geometrie paramétrable
 				message.append(once " hires_y=")
 				(y/65000).append_in(message) -- **** geometrie paramétrable
				message.append(once " proximity=")
				message.append(proximity_description)
		end
	
	button(pressed: BOOLEAN; pointer: X_INPUT_DEVICE) is
		local
			x, y, presure: INTEGER
			t3: REAL_64
			message: STRING
		do
			x := pointer.motion_axis_data(1) 
			y := pointer.motion_axis_data(2)
			--update_predicted_position(x, y, pointer.event_time)
			x_history.remove_first
			x_history.add_last(x)
			y_history.remove_first
			y_history.add_last(y)
			time_history.remove_first
			time_history.add_last(pointer.event_time)
			t3 := mean(time_history)
			if t3 /= t2 then
				update_predicted_position(mean(x_history), mean(y_history), t3)
			end
			message := once ""
			message.copy(button_message_header)				
			message.append(once " button=")
			pointer.button_number.append_in(message)
			message.append(once " status=")
			if pressed then
				message.append(once "down")
			else
				message.append(once "up")
			end
			presure := pointer.motion_axis_data(3)
			print_data_in(message, x, y, presure, pointer.motion_axis_data(4),
							  pointer.motion_axis_data(5),
							  pointer.motion_axis_data(6), pointer.event_time,
							  once "unchanged")
			xinput_ivy.ivy.send_message(message)
		end
	
	proximity(in: BOOLEAN; pointer: X_INPUT_DEVICE) is
		local
			x, y: INTEGER
			t3: REAL_64
			message, proximity_status: STRING
		do
			x := pointer.proximity_axis_data(1) 
			y := pointer.proximity_axis_data(2)
			--update_predicted_position(x, y, pointer.event_time)
			--*** exploiter le cas proximity in=True pour vider l'historique
			x_history.remove_first
			x_history.add_last(x)
			y_history.remove_first
			y_history.add_last(y)
			time_history.remove_first
			time_history.add_last(pointer.event_time)
			t3 := mean(time_history)
			if t3 /= t2 then
				update_predicted_position(mean(x_history), mean(y_history), t3)
			end
			if in then
				proximity_status := once "In"
			else
				proximity_status := once "Out"
			end
			message := once ""
			message.copy(pointer_message_header)
			print_data_in(message, x, y, pointer.proximity_axis_data(3),
							  pointer.proximity_axis_data(4),
							  pointer.proximity_axis_data(5),
							  pointer.proximity_axis_data(6),
							  pointer.event_time, proximity_status)
			xinput_ivy.ivy.send_message(message)
		end

	predicted_x, predicted_y: INTEGER

	int_update_predicted_position(x3, y3, t3: INTEGER) is
		local
			dt: REAL -- delta time, temporary value
			s3x, s3y, s3: REAL -- speed beetween P2 and P3
			s3xn, s3yn: REAL -- normalized speed between point P2 and P3
			a3x, a3y: REAL -- acceleration at point P2 (needs P3!)
			a3xm, a3ym: REAL -- a3 value in mobile coordinates (s2 vector)
			a4x, a4y: REAL -- a3 value rotated by (s2 vector, s3 vector) angle
		do
			dt := t3 - t2
			--s3x := (x3 - x2).to_real_64 / dt
			--s3y := (y3 - y2).to_real_64 / dt
			s3 := (s3x * s3x + s3y * s3y).sqrt
			s3xn := s3x / s3
			s3yn := s3y / s3

			dt := (t3 - t1) / 2
			a3x := (s3x - s2x) / dt
			a3y := (s3y - s2y) / dt
			a3xm := a3x * s2xn + a3y * s2yn
			a3ym := -a3x * s2yn + a3y * s2xn
			a4x := s3xn * a3xm - s3yn * a3ym
			a4y := s3yn * a3xm + s3xn * a3ym

			dt := (t3 - t2 + prediction_time) / 2
			predicted_x := x3 + (prediction_time * (s3x + a4x * dt)).force_to_integer_32
			predicted_y := y3 + (prediction_time * (s3y + a4y * dt)).force_to_integer_32

			if (prediction_time * (s3y + a4y * dt)).abs > 5300 then
				io.put_string(once "x2=" + x2.to_string + once " y2=" + y2.to_string)
				io.put_string(once " x3=" + x3.to_string + once " y3=" + y3.to_string)
				io.put_string(once " s3x=" + s3x.to_string + once " s3y=" + s3y.to_string)
				io.put_string(once " a3x=" + a3x.to_string + once " a3y=" + a3y.to_string)
				io.put_string(once " a3xm=" + a3xm.to_string + once " a3ym=" + a3ym.to_string)
				io.put_string(once " a4x=" + a4x.to_string + once " a4y=" + a4y.to_string)
				io.put_string(once " dt=" + dt.to_string)
				io.put_string(once " ****")
				io.put_new_line
			end
			-- Shift values
			x2 := x3; y2 := y3
			s2x := s3x; s2y := s3y
			s2xn := s3xn; s2yn := s3yn
			t1 := t2; t2 := t3
		end

	update_predicted_position(x3, y3, t3: REAL) is
		require
			t2 /= t3
		local
			dt: REAL -- delta time, temporary value
			s3x, s3y, s3: REAL -- speed beetween P2 and P3
			s3xn, s3yn: REAL -- normalized speed between point P2 and P3
			a3x, a3y: REAL -- acceleration at point P2 (needs P3!)
			a3xm, a3ym: REAL -- a3 value in mobile coordinates (s2 vector)
			a4x, a4y: REAL -- a3 value rotated by (s2 vector, s3 vector) angle
		do
			dt := t3 - t2
			s3x := (x3 - x2) / dt
			s3y := (y3 - y2) / dt
			s3 := (s3x * s3x + s3y * s3y).sqrt
			if s3 /= 0 then
				s3xn := s3x / s3
				s3yn := s3y / s3
			end

			dt := (t3 - t1) / 2
			a3x := (s3x - s2x) / dt
			a3y := (s3y - s2y) / dt
			a3xm := a3x * s2xn + a3y * s2yn
			a3ym := -a3x * s2yn + a3y * s2xn
			a4x := s3xn * a3xm - s3yn * a3ym
			a4y := s3yn * a3xm + s3xn * a3ym

			--dt := (t3 - t2 + prediction_time) / 2
			-- acceleration is constant
			-- predicted_x := (x3 + prediction_time * (s3x + a3x * dt)).force_to_integer_32
			-- predicted_y := (y3 + prediction_time * (s3y + a3y * dt)).force_to_integer_32

			-- acceleration is constant in mobile coordinates
			-- predicted_x := (x3 + prediction_time * (s3x + a4x * dt)).force_to_integer_32
			-- predicted_y := (y3 + prediction_time * (s3y + a4y * dt)).force_to_integer_32

			-- acceleration variation is constant
			-- a4x := a3x + (a3x - a2x) * (prediction_time + t2 - t1) / (t3 + t1 - t2 - t0)
			-- a4y := a3y + (a3y - a2y) * (prediction_time + t2 - t1) / (t3 + t1 - t2 - t0)
			-- predicted_x := (x3 + prediction_time * (s3x + a4x * dt)).force_to_integer_32
			-- predicted_y := (y3 + prediction_time * (s3y + a4y * dt)).force_to_integer_32

			-- half constant in mobile coordinates, half constant variation
			dt := (prediction_time + t2 - t1) / (t3 + t1 - t2 - t0)
			a4x := (a4x + a3x + (a3x - a2x) * dt) / 2
			a4y := (a4y + a3y + (a3y - a2y) * dt) / 2
			
			dt := (t3 - t2 + prediction_time) / 2
			predicted_x := (x3 + prediction_time * (s3x + a4x * dt)).force_to_integer_32
			predicted_y := (y3 + prediction_time * (s3y + a4y * dt)).force_to_integer_32

			-- Shift values
			x2 := x3; y2 := y3
			s2x := s3x; s2y := s3y
			s2xn := s3xn; s2yn := s3yn
			a2x := a3x; a2y := a3y
			t0 := t1; t1 := t2; t2 := t3
		end

	a2x, a2y: REAL

	t0: REAL
	
	--x2, y2: INTEGER -- point P2 coordinates
	x2, y2: REAL -- point P2 coordinates

	s2x, s2y: REAL -- speed beetween P1 and P2

	s2xn, s2yn: REAL -- normalized speed between P1 and P2

	--t1, t2: INTEGER -- timestamp for points P1 and P2
	t1, t2: REAL -- timestamp for points P1 and P2
	
end