# Synth module.
#
# This script is more advanced, and some programming experience is
# expected here. It's a synth module where we use two synths, one based
# on FluidSynth, and the other based on ZynAddSubFx. This script
# demonstrates most of the things jacktube is capable of, from
# dymanic plugin loading to arrays and dynamic port names.
#
# The tricky part is that FluidSynth has a DSSI plugin, whereas
# ZynAddSubFx does not (*), so we need to switch between those two
# cases properly. Also take into account that we have many channels,
# and the script becomes quite advanced.
#
# This script requires some outside setup too. To use it, do the
# following:
#
#    1. Install the FluidSynth DSSI plugin.
#    2. Put a set of soundfonts in a file called "instruments.sf2" and
#       put it in the current directory.
#    3. Launch ZynAddSubFx with some patches.
#    4. Run "jacktube -R complex-synth-module.jt".
#    5. Connect the following jack ports:
#          ZynAddSubFx:left  -> Jacktube:zyn_l
#          ZynAddSubFx:right -> Jacktube:zyn_r
#          Jacktube:out1_l   -> system:playback_1
#          Jacktube:out1_r   -> system:playback_2
#       The two last ones will be for channel 1 sound only.
#    6. Connect the following MIDI sequencer ports:
#          <Your-MIDI-Device>:out -> Jacktube:in
#          Jacktube:out_zyn       -> ZynAddSubFx:input
#    7. Try playing your keyboard and switching banks. Bank zero is
#       FluidSynth, and bank one is Zyn.

# (*) ZynAddSubFx has since gained a DSSI plugin, but this script
#     is useful nevertheless for educational purposes.


# The following is a common concept in jacktube scripts: Status
# variables hold various information about the state of the script,
# which is used to match later on.
#
# Note the lack of a looping operator to assign consecutive numbers.
# This is a deliberate design choice in the language: Jacktube
# normally runs in a realtime environment, and this places constraints
# on the amount of processing you can do. Since it is not easy to type
# in large amounts of processing in a script, this forces you to think
# about what you are entering.
#
# Each element of each array corresponds to one channel. The $plugins
# array simply holds that very channel if the FluidSynth plugin is
# active, and -1 otherwise. This is used to match events later on.

$plugins[0] = 0;
$plugins[1] = 1;
$plugins[2] = 2;
$plugins[3] = 3;
$plugins[4] = 4;
$plugins[5] = 5;
$plugins[6] = 6;
$plugins[7] = 7;
$plugins[8] = 8;
$plugins[9] = 9;
$plugins[10] = 10;
$plugins[11] = 11;
$plugins[12] = 12;
$plugins[13] = 13;
$plugins[14] = 14;
$plugins[15] = 15;

# The $zyn array is like the $plugin array, but counts toward
# ZynAddSubFx being active instead.

$zyn[0] = -1;
$zyn[1] = -1;
$zyn[2] = -1;
$zyn[3] = -1;
$zyn[4] = -1;
$zyn[5] = -1;
$zyn[6] = -1;
$zyn[7] = -1;
$zyn[8] = -1;
$zyn[9] = -1;
$zyn[10] = -1;
$zyn[11] = -1;
$zyn[12] = -1;
$zyn[13] = -1;
$zyn[14] = -1;
$zyn[15] = -1;

# ZynAddSubFx only deals with channels, and doesn't have the concept of
# program changes. Therefore we keep track of which patch we want on
# ZynAddSubFx here, and translate that to the correct channel value
# when we send events to Zyn.

$zynprogram[0] = 0;
$zynprogram[1] = 0;
$zynprogram[2] = 0;
$zynprogram[3] = 0;
$zynprogram[4] = 0;
$zynprogram[5] = 0;
$zynprogram[6] = 0;
$zynprogram[7] = 0;
$zynprogram[8] = 0;
$zynprogram[9] = 0;
$zynprogram[10] = 0;
$zynprogram[11] = 0;
$zynprogram[12] = 0;
$zynprogram[13] = 0;
$zynprogram[14] = 0;
$zynprogram[15] = 0;

# We use banks to switch between Fluid and Zyn. Bank 0 is Fluid, 1 is
# Zyn.

# Bank MSB for each channel. We only send out both messages after both
# have arrived.

$bankMSB[0] = -1;
$bankMSB[1] = -1;
$bankMSB[2] = -1;
$bankMSB[3] = -1;
$bankMSB[4] = -1;
$bankMSB[5] = -1;
$bankMSB[6] = -1;
$bankMSB[7] = -1;
$bankMSB[8] = -1;
$bankMSB[9] = -1;
$bankMSB[10] = -1;
$bankMSB[11] = -1;
$bankMSB[12] = -1;
$bankMSB[13] = -1;
$bankMSB[14] = -1;
$bankMSB[15] = -1;

# Bank LSB for each channel. We only send out both messages after both
# have arrived.

$bankLSB[0] = -1;
$bankLSB[1] = -1;
$bankLSB[2] = -1;
$bankLSB[3] = -1;
$bankLSB[4] = -1;
$bankLSB[5] = -1;
$bankLSB[6] = -1;
$bankLSB[7] = -1;
$bankLSB[8] = -1;
$bankLSB[9] = -1;
$bankLSB[10] = -1;
$bankLSB[11] = -1;
$bankLSB[12] = -1;
$bankLSB[13] = -1;
$bankLSB[14] = -1;
$bankLSB[15] = -1;

# The final bank number after both MSB and LSB have been received.

$bank[0] = 0;
$bank[1] = 0;
$bank[2] = 0;
$bank[3] = 0;
$bank[4] = 0;
$bank[5] = 0;
$bank[6] = 0;
$bank[7] = 0;
$bank[8] = 0;
$bank[9] = 0;
$bank[10] = 0;
$bank[11] = 0;
$bank[12] = 0;
$bank[13] = 0;
$bank[14] = 0;
$bank[15] = 0;

# Volumes for each channel.

$volume[0] = 127;
$volume[1] = 127;
$volume[2] = 127;
$volume[3] = 127;
$volume[4] = 127;
$volume[5] = 127;
$volume[6] = 127;
$volume[7] = 127;
$volume[8] = 127;
$volume[9] = 127;
$volume[10] = 127;
$volume[11] = 127;
$volume[12] = 127;
$volume[13] = 127;
$volume[14] = 127;
$volume[15] = 127;

# Load and connect FluidSynth plugins for each channel.

%instr[0] = "FluidSynth-DSSI";
%instr[0].configure("load", "instruments.sf2");
>~out1_l ~ %instr[0]["Output L"];
>~out1_r ~ %instr[0]["Output R"];
%instr[1] = "FluidSynth-DSSI";
%instr[1].configure("load", "instruments.sf2");
>~out2_l ~ %instr[1]["Output L"];
>~out2_r ~ %instr[1]["Output R"];
%instr[2] = "FluidSynth-DSSI";
%instr[2].configure("load", "instruments.sf2");
>~out3_l ~ %instr[2]["Output L"];
>~out3_r ~ %instr[2]["Output R"];
%instr[3] = "FluidSynth-DSSI";
%instr[3].configure("load", "instruments.sf2");
>~out4_l ~ %instr[3]["Output L"];
>~out4_r ~ %instr[3]["Output R"];
%instr[4] = "FluidSynth-DSSI";
%instr[4].configure("load", "instruments.sf2");
>~out5_l ~ %instr[4]["Output L"];
>~out5_r ~ %instr[4]["Output R"];
%instr[5] = "FluidSynth-DSSI";
%instr[5].configure("load", "instruments.sf2");
>~out6_l ~ %instr[5]["Output L"];
>~out6_r ~ %instr[5]["Output R"];
%instr[6] = "FluidSynth-DSSI";
%instr[6].configure("load", "instruments.sf2");
>~out7_l ~ %instr[6]["Output L"];
>~out7_r ~ %instr[6]["Output R"];
%instr[7] = "FluidSynth-DSSI";
%instr[7].configure("load", "instruments.sf2");
>~out8_l ~ %instr[7]["Output L"];
>~out8_r ~ %instr[7]["Output R"];
%instr[8] = "FluidSynth-DSSI";
%instr[8].configure("load", "instruments.sf2");
>~out9_l ~ %instr[8]["Output L"];
>~out9_r ~ %instr[8]["Output R"];
%instr[9] = "FluidSynth-DSSI";
%instr[9].configure("load", "instruments.sf2");
>~out10_l ~ %instr[9]["Output L"];
>~out10_r ~ %instr[9]["Output R"];
%instr[10] = "FluidSynth-DSSI";
%instr[10].configure("load", "instruments.sf2");
>~out11_l ~ %instr[10]["Output L"];
>~out11_r ~ %instr[10]["Output R"];
%instr[11] = "FluidSynth-DSSI";
%instr[11].configure("load", "instruments.sf2");
>~out12_l ~ %instr[11]["Output L"];
>~out12_r ~ %instr[11]["Output R"];
%instr[12] = "FluidSynth-DSSI";
%instr[12].configure("load", "instruments.sf2");
>~out13_l ~ %instr[12]["Output L"];
>~out13_r ~ %instr[12]["Output R"];
%instr[13] = "FluidSynth-DSSI";
%instr[13].configure("load", "instruments.sf2");
>~out14_l ~ %instr[13]["Output L"];
>~out14_r ~ %instr[13]["Output R"];
%instr[14] = "FluidSynth-DSSI";
%instr[14].configure("load", "instruments.sf2");
>~out15_l ~ %instr[14]["Output L"];
>~out15_r ~ %instr[14]["Output R"];
%instr[15] = "FluidSynth-DSSI";
%instr[15].configure("load", "instruments.sf2");
>~out16_l ~ %instr[15]["Output L"];
>~out16_r ~ %instr[15]["Output R"];

$fluidgain = "0.398107";
%instr[0].configure("GLOBAL:gain", $fluidgain);
$fluidpoly = "64";
%instr[0].configure("GLOBAL:polyphony", $fluidpoly);

# Match keys and pitchbend first, to minimize latency.
final [<@in, all, type[keyon]-type[pitch], all, all]
{
	if ($plugins[event[channel]] == event[channel]) {
		%instr[event[channel]] = [0, event[type], event[param], event[value]];
	} else {
		>@out_zyn = [$zynprogram[event[channel]], event[type], event[key], event[value]];
	}
}

# Switch between the banks.
# Only when both MSB and LSB have been received do we switch.

# Used to match bank switch.

$bankMatcher = -1;

# Used to match a final scope which prevents propogation of banks.

$nonBankMatcher = -1;

[<@in, all, type[control], 0, all]
{
	$bankMatcher = -1;
	$nonBankMatcher = event[param];
	$bankMSB[event[channel]] = event[value];
	if ($bankLSB[event[channel]] != -1) {
		$bankMatcher = event[param];
	}
}
[<@in, all, type[control], 32, all]
{
	$bankMatcher = -1;
	$nonBankMatcher = event[param];
	$bankLSB[event[channel]] = event[value];
	if ($bankMSB[event[channel]] != -1) {
		$bankMatcher = event[param];
	}
}

# This is where we do the actual bank switch from FluidSynth to Zyn and
# vice versa.

# "Local" variable.
$bankToBe = 0;
final [<@in, all, type[control], $bankMatcher, all]
{
	$bankToBe = $bankMSB[event[channel]] * 128 + $bankLSB[event[channel]];
	if ($bankToBe == 1) {
		$plugins[event[channel]] = -1;
		$zyn[event[channel]] = event[channel];

		# Nifty dynamic port assigment to keep the audio bound to the channel.
		>~{"out" + int(event[channel] + 1) + "_l"} ~ <~zyn_l;
		>~{"out" + int(event[channel] + 1) + "_r"} ~ <~zyn_r;
	} else {
		$plugins[event[channel]] = event[channel];
		$zyn[event[channel]] = -1;

		>~{"out" + int(event[channel] + 1) + "_l"} ~ %instr[event[channel]]["Output L"];
		>~{"out" + int(event[channel] + 1) + "_r"} ~ %instr[event[channel]]["Output R"];
	}

	$bank[event[channel]] = $bankToBe;
	$bankMSB[event[channel]] = -1;
	$bankLSB[event[channel]] = -1;
}
final [<@in, all, type[control], $nonBankMatcher, all]
{
	# Prevent propogation of banks.
	stop;
}

final [<@in, $zyn[event[channel]], type[program], all, all]
{
	$zynprogram[event[channel]] = event[value];
}
final [<@in, all, type[program], all, all]
{
	%instr[event[channel]] = [0, event[type], event[param], event[value]];
	%instr[event[channel]] = [0, type[control], 7, $volume[event[channel]]];
}

[<@in, all, type[control], 7, all]
{
	# The volume propogation happens further down.
	$volume[event[channel]] = event[value];
}

# GUI stuff. Use general purpose button CC 82 to launch GUI.
final [<@in, $plugins[event[channel]], type[control], 82, 64-127]
{
	%instr[event[channel]].show_gui("Channel " + int(event[channel] + 1), configure_print);
}
final [<@in, $plugins[event[channel]], type[control], 82, 0-63]
{
	%instr[event[channel]].hide_gui();
}

# Forward the rest of the MIDI messages.
[<@in, $plugins[event[channel]], all, all, all]
{
	%instr[event[channel]] = [0, event[type],
			event[param], event[value]];
}
[<@in, $zyn[event[channel]], all, all, all]
{
	>@out_zyn = [$zynprogram[event[channel]], event[type], event[key], event[value]];
}