// title: God Rest Ye Merry, Xentlemen
// author: walters
// description:
// Xenharmonic rendering of the Xmas favorite
// code:
// GOD REST YE MERRY, XENTLEMEN
// The Christmas sensation in just intonation with harmonization by ring modulation

// Tim Walters, 2023
// see https://timwalters.bandcamp.com for lots of questionable holiday music (some SuperCollider, some not)

// first boot server, send/store synthdefs and set up melody data
(
~sampleRate = 96000; // much easier than trying to anti-alias ring modulation + distortion
Server.default.options.sampleRate_(~sampleRate);

Server.default.waitForBoot {
	var rawNotes, rawVels, rawTimes, times, freqDrift;

	// a little frequency instability still sounds better, even in just intonation
	freqDrift = { |freq| (freq.cpsmidi + LFDNoise3.kr(0.2, mul: 0.03)).midicps };

	// defs
	SynthDef(\ringmod, { |out=0, t_trig=1, amp=0.125, vel=0.5, freq=220, freq2=110, attackTime=0.05, decayTime=1.0|
		var env, osc1, osc2, osc3, rings, sig, releaser, vol, follower, filtscale, filt;

		// velocity-dependent decay envelope
		env = Decay2.kr(t_trig, attackTime * LinLin.kr(vel, 1, 0, 0.5, 2.0), decayTime * LinLin.kr(vel, 0, 1, 0.8, 1.25));

		// base oscillator
		osc1 = SinOsc.ar(freqDrift.(freq));

		// scale volume pre- and post-distortion by velocity
		vol = LinLin.kr(vel, 0, 1, -12, 0).dbamp;

		// ring modulate (multiply) with both freq2 and a just fifth above
		// sent to left and right channels
		osc2 = SinOsc.ar(freqDrift.(freq2));
		osc3 = SinOsc.ar(freqDrift.(freq2 * 1.5));
		rings = ([osc1 * osc2, osc1 * osc3] * 8 * vol).distort;

		// mix some of the base frequencies back in
		// I don't understand why wrapping the env in K2A sounds different, but it does
		sig = (rings + (osc1 + (osc2 * -6.dbamp)).dup) * K2A.ar(env) * amp * vol;

		// gentle filter controlled by amplitude and velocity
		follower = Amplitude.ar(sig);
		filtscale = LinLin.kr(freq2.cpsmidi, 60, 84, 1, 0.5) * vel.sqrt;
		filt = LPF.ar(sig, LinLin.ar(follower, 0, 1, 7, 10) * freq * filtscale);

		// give Fletcher and Munson a break
		filt = BPeakEQ.ar(filt, 3500, 0.5, -5);

		releaser = DetectSilence.ar(filt, -84.dbamp, doneAction: 2);
		OffsetOut.ar(out, filt);
	}).store.add;

	SynthDef(\bass, { |out=0, gate=1, t_trig=0, amp=0.125, freq=220, decayTime=8.0, coef=0.25|
		var pluck = Pluck.ar({ PinkNoise.ar(0.5) } ! 2, t_trig, freq.reciprocal, freq.reciprocal, decayTime, coef);
		var releaser = EnvGen.ar(Env.asr(0, 1, decayTime), gate, doneAction: 2);
		OffsetOut.ar(out, (pluck * 16).distort * SinOsc.ar(freq) * amp)
	}).store.add;

	SynthDef(\verb, { |out=0, wet=0.25, predelay=0.05, gate=1|
		var in = DelayN.ar(In.ar(out, 2), delaytime: predelay);
		XOut.ar(out, wet, GVerb.ar(in.sum, 250, revtime: 2, drylevel: 0, earlyreflevel: -12.dbamp, taillevel: 0.dbamp));
	}, [\ir, 0.1, 0.1, 0]).store.add;

	// performance data from hand-played MIDI
	rawNotes = [ 64, 64, 71, 71, 69, 67, 66, 64, 62, 64, 66, 67, 69, 71, 64, 64, 71, 71,
		69, 67, 66, 64, 62, 64, 66, 67, 69, 71, 71, 72, 69, 71, 72, 74, 76, 71, 69, 67,
		64, 66, 67, 69, 67, 69, 71, 72, 71, 71, 69, 67, 66, 64, 67, 66, 64, 69, 67, 69,
		71, 72, 74, 76, 71, 69, 67, 66, 64, 64, 64, 71, 71, 69, 67, 66, 64, 62, 64, 66,
		67, 69, 71, 64, 64, 71, 71, 69, 67, 66, 64, 62, 64, 66, 67, 69, 71, 71, 72, 69,
		71, 72, 74, 76, 71, 69, 67, 64, 66, 67, 69, 67, 69, 71, 72, 71, 71, 69, 67, 66,
		64, 67, 66, 64, 69, 67, 69, 71, 72, 74, 76, 71, 69, 67, 66, 64 ];
	rawVels = [ 70, 74, 74, 76, 83, 79, 71, 69, 68, 73, 60, 72, 72, 72, 69, 88, 79, 78,
		83, 77, 62, 55, 83, 79, 74, 86, 82, 73, 85, 81, 82, 82, 85, 83, 104, 86, 78, 88,
		69, 66, 74, 69, 77, 81, 74, 79, 69, 71, 71, 78, 62, 65, 73, 62, 71, 75, 84, 80,
		77, 87, 81, 97, 88, 86, 85, 80, 76, 76, 79, 74, 76, 68, 76, 70, 79, 79, 81, 69,
		80, 72, 74, 74, 82, 79, 83, 84, 74, 74, 72, 79, 69, 66, 79, 79, 78, 86, 88, 83,
		82, 84, 88, 103, 86, 84, 81, 81, 74, 81, 62, 87, 79, 84, 84, 81, 81, 82, 80, 74,
		75, 80, 88, 62, 66, 80, 86, 83, 86, 82, 88, 86, 85, 84, 91, 72
	];
	rawTimes = [ 30272, 43202, 56016, 68580, 80946, 93382, 106876, 120352, 158818, 172154,
		185970, 199026, 213208, 227362, 288390, 300902, 313402, 325380, 337744, 350324,
		364148, 378000, 415974, 428500, 441878, 455242, 468262, 482612, 548014, 560434,
		573552, 586122, 599528, 613018, 626646, 639698, 680236, 693534, 706470, 720296,
		734578, 749356, 814508, 827088, 839560, 865932, 878806, 892792, 905772, 918564,
		932114, 945794, 972798, 978774, 985758, 998882, 1069610, 1082090, 1095602, 1108404,
		1121810, 1135642, 1148322, 1162650, 1176864, 1190834, 1206372, 1304640, 1319096,
		1332192, 1345078, 1359110, 1372204, 1385426, 1400638, 1440742, 1454038, 1466804,
		1480064, 1493634, 1507450, 1568292, 1580988, 1593828, 1606050, 1619316, 1632210,
		1645800, 1658950, 1703150, 1716222, 1729796, 1742988, 1757022, 1771082, 1830026,
		1843488, 1856088, 1868844, 1882152, 1895876, 1909496, 1923418, 1967164, 1980738,
		1994512, 2007926, 2022132, 2036510, 2098256, 2110542, 2123764, 2150164, 2162802,
		2175516, 2188310, 2201676, 2214308, 2227136, 2252892, 2258638, 2265816, 2278922,
		2344746, 2356914, 2369874, 2381800, 2394730, 2407328, 2420948, 2434120, 2447818,
		2461264, 2477334 ];

	// normalize values
	~degrees = rawNotes - 64; // performed in E minor
	~vels = rawVels / 127.0;
	times = rawTimes  / 19200.0;
	// get diffs between times and add a final arbitrary one to get right number
	~durs = times.differentiate.drop(1) ++ [5];
	~renderDuration = times.last + 10; // needed for NRT

	// data integrity check
	if (~degrees.size != ~vels.size || ~degrees.size != ~durs.size) { Error("Melody data is inconsistent.").throw; };
}
)

// turn melody data into piece
(
var scale, root, degree2s, freq2s, bassPlays, bassDurs, bassDegrees, prevDegree, basePattern;

// scale is actually minor, but it comes in chromatically from the MIDI data
scale = Scale.chromatic(\just);

// could transpose here
root = 4;

// will determine ring modulation frequencies
degree2s = [
	0, 0, 0, -2, -2, 0, 0, 0, -5, 0, 0, -4, -4, 0,
	0, 0, 0, -2, -2, 0, 0, 0, -5, 0, 0, -4, -4, -5,
	-5, 3, 3, 3, 3, 2, 2, 3, 3, 0, 0, 0, 0, -2,
	0, 0, 3, -4, -4, -2, -2, -5, -5, 3, -4, -4, -4, 5,
	-2, -2, 3, 3, 2, 2, -2, -2, -5, -5, 0
];

// Event will handle conversion to \freq, but we have to do \freq2 ourselves
// Higher octave on second repetition changes harmonization, timbre, and even apparent
// octave of melody
freq2s = [5, 6].collect { |octave| degree2s.collect { |n| scale.degreeToFreq(n, root.midicps, octave) } }.flatten;

// generate bass part doubling ring modulation frequencies, without rearticulation or pickup notes
// lay out first time through
bassPlays = (\rest ! degree2s.size) ++ [\rest] ++ (\on ! 13) ++ [\rest] ++ (\on ! 13)
++ [\rest] ++ (\on ! 13) ++ [\rest, \rest] ++ (\on ! 12) ++ [\rest, \rest] ++ (\on ! 9);

// data integrity check
if (~degrees.size != freq2s.size || ~degrees.size != bassPlays.size) { Error("Harmony data is inconsistent.").throw; };

bassDurs = List[];
bassDegrees = List[];
prevDegree = \rest;
bassPlays.do { |val, i|
	var degree = (val == \on).if { degree2s.wrapAt(i) } { \rest };
	if ((degree != \rest) && (prevDegree == degree)) {
		bassDurs[bassDurs.lastIndex] = bassDurs.last + ~durs[i]
	} {
		bassDurs.add(~durs[i]); bassDegrees.add(degree)
	};
	prevDegree = degree;
};

// notes...
basePattern = Ptpar([
	0.25,
	Pbind(
		\instrument, \ringmod,
		\scale, scale,
		\root, root,
		\degree, Pseq(~degrees, 1),
		\octave, 6,
		\dur, Pseq(~durs, 1),
		\freq2, Pseq([5, 6].collect { |octave| degree2s.collect { |n| scale.degreeToFreq(n, root.midicps, octave) } }.flatten, 1),
		\decayTime, 4.0,
		\amp, 0.dbamp,
		\vel, Pseq(~vels, 1)
	),
	0.25,
	Pmono(
		\bass,
		\scale, scale,
		\root, root,
		\degree, Pseq(bassDegrees, 1),
		\trig, Pseq(bassDegrees.collect { |d| (d === \rest).if { 0 } { 1 } }, 1),
		\octave, 3,
		\dur, Pseq(bassDurs, 1),
		\coef, 0.8,
		\amp, -6.dbamp,
		\decayTime, 8.0
	)
]);

// with reverb
~xentlemen = Pfxb(basePattern, \verb, \wet, 0.25, \predelay, 0.025);
)

// play...
r = ~xentlemen.play;