From 18cfda27f63fd0b1c30591057207697aec957b3a Mon Sep 17 00:00:00 2001
From: Hanspeter Portner <dev@open-music-kontrollers.ch>
Date: Sat, 13 Apr 2024 14:00:31 +0200
Subject: [PATCH] Add Shifter

---
 lua/liam.lua     | 36 +++++++++++++++++----
 lua/shifting.lua | 81 ++++++++++++++++++++++++++++++++++++++++++++++++
 meson.build      |  7 +++++
 3 files changed, 118 insertions(+), 6 deletions(-)
 create mode 100644 lua/shifting.lua

diff --git a/lua/liam.lua b/lua/liam.lua
index 886a2e4..94ea742 100755
--- a/lua/liam.lua
+++ b/lua/liam.lua
@@ -13,6 +13,7 @@ local displaying <const> = require('displaying')
 local tonewheeling <const> = require('tonewheeling')
 local pianoteqing <const> = require('pianoteqing')
 local gatekeeping <const> = require('gatekeeping')
+local shifting <const> = require('shifting')
 
 local tags <const> = {
 	clock = 'clock',
@@ -94,6 +95,31 @@ local tonewheel <const> = tonewheeling.Tonewheel:new {
 }
 interface[6] = tonewheel
 
+local shifter1 <const> = shifting.Shifter:new {
+	channel = 0x0,
+	interface = interface --FIXME
+}
+interface[7] = shifter1
+
+local shifter2 <const> = shifting.Shifter:new {
+	channel = 0x1,
+	interface = interface --FIXME
+}
+interface[8] = shifter2
+
+local shifter3 <const> = shifting.Shifter:new {
+	channel = 0x2,
+	interface = interface --FIXME
+}
+interface[9] = shifter3
+
+local shifter4 <const> = shifting.Shifter:new {
+	channel = 0x3,
+	interface = interface --FIXME
+}
+interface[10] = shifter4
+interface.index = 9 --FIXME
+
 local monitor <const> = monitoring.Monitor:new()
 
 local pk88 <const> = {
@@ -164,23 +190,21 @@ function process(nframes)
 			if gatekeeper1:pass(msg) then
 				local msg <const> = table.pack(table.unpack(msg))
 
-				msg[1] = (msg[1] & 0xf0) | 0x00 -- channel 1
-				fh2.writer:write(time, msg)
+				fh2.writer:write(time, shifter1:shift(msg))
 			end
 
 			if gatekeeper2:pass(msg) then
 				local msg <const> = table.pack(table.unpack(msg))
 
-				msg[1] = (msg[1] & 0xf0) | 0x01 -- channel 2
-				fh2.writer:write(time, msg)
+				fh2.writer:write(time, shifter2:shift(msg))
 			end
 
 			if not pianoteq.mute and gatekeeper3:pass(msg) then
-				piano.writer:write(time, msg)
+				piano.writer:write(time, shifter3:shift(msg))
 			end
 
 			if not tonewheel.mute and gatekeeper4:pass(msg) then
-				bfree.writer:write(time, msg)
+				bfree.writer:write(time, shifter4:shift(msg))
 			end
 		elseif source == fh2.reader then
 			monitor:write(time, msg)
diff --git a/lua/shifting.lua b/lua/shifting.lua
new file mode 100644
index 0000000..d12259b
--- /dev/null
+++ b/lua/shifting.lua
@@ -0,0 +1,81 @@
+-- SPDX-FileCopyrightText: Hanspeter Portner <dev@open-music-kontrollers.ch>
+-- SPDX-License-Identifier: Artistic-2.0
+
+local tooling <const> = require('tooling')
+local interfacing <const> = require('interfacing')
+
+local Offset <const> = tooling.Class:new {
+	color_off = 0x1,
+	color_act = 0xd,
+	color_hot = 0x3,
+
+	down = function(self, time)
+		self.pressed = true
+
+		self.page:set_offset(time, self.offset)
+	end,
+
+	up = function(self, time)
+		self.pressed = false
+	end,
+
+	color = function(self)
+		if self.pressed then
+			return self.color_hot
+		elseif self.offset == self.page.offset then
+			return self.color_act
+		else
+			return self.color_off
+		end
+	end
+}
+
+local Shifter <const> = interfacing.Page:new {
+	channel = 0x0,
+	offset = 0,
+
+	-- private
+	octave_offset = 0,
+	note_offset = 0,
+
+	set_offset = function(self, time, offset)
+		self.offset = offset
+		self:refresh(time)
+	end,
+
+	init = function(self)
+		interfacing.Page.init(self)
+
+		--FIXME separate block for notes
+
+		for j = 1, 9 do
+			local offset <const> = j - 5
+			local num <const> = 10 + j
+
+			self[num] = Offset:new {
+				offset = offset,
+				page = self
+			}
+		end
+	end,
+
+	shift = function(self, msg)
+		local cmd <const> = msg[1] & 0xf0
+
+		-- check for matching note range
+		if cmd == midi.NoteOn
+		or cmd == midi.NoteOff
+		or cmd == midi.NotePressure then
+			return { cmd | self.channel, msg[2] + self.offset, msg[3] }
+		end
+
+		return msg
+	end
+}
+
+-- module
+local shifting <const> = {
+	Shifter = Shifter
+}
+
+return shifting
diff --git a/meson.build b/meson.build
index d4fa2c6..b6eafef 100644
--- a/meson.build
+++ b/meson.build
@@ -130,6 +130,13 @@ gatekeeping_lua = configure_file(
 	install : true,
 	install_dir : lua_datadir)
 
+shifting_lua = configure_file(
+	input : join_paths('lua', 'shifting.lua'),
+	output : 'shifting.lua',
+	copy : true,
+	install : true,
+	install_dir : lua_datadir)
+
 if build_tests
   if reuse.found()
     test('REUSE', reuse, args : [
-- 
2.38.5