#!/usr/bin/python

# Serial Composition script  for Aj Klhic B-Fedg
# By Kevin Cox        > http://www.jibberia.com/
# uses the Python Midi Package
# > http://www.mxm.dk/products/public/pythonmidi

import MidiOutFile,random
random.seed()

def inc11(var):
	var = var + 1
	if var > 11: return 0
	else: return var

# fun config stuff
prime = [ 0, 9, 10, 11, 7, 8, 2, 1, 5, 4, 3, 6 ]
inver = [ 0, 3, 2, 1, 5, 4, 10, 11, 7, 8, 9, 6 ]
rsix  = [ 6, 3, 4, 5, 1, 2, 8, 7, 11, 10, 9, 0 ]
out_file = 'serial.mid' #name of output file
generate = 30 # seconds
basepitch = 60+12 # midi note number (60 == middle C)
basedur = 192 / 12 # == 16 ticks (192 ticks == 1 second)

cpitch, camp, cdur, totaldur, octdev = 0, 0, 0, 0, 0
midi = MidiOutFile.MidiOutFile(out_file)
midi.header(format=1, nTracks=3)

# track 0 - melody
midi.start_of_track(0)
while totaldur < (192 * generate):
	len = basedur * (prime[cdur] + 1)
	pitch = basepitch + prime[cpitch]

	midi.update_time(0)
	midi.note_on(channel=0, note=pitch, velocity=100)

	midi.update_time(len)
	midi.note_off(channel=0, note=pitch, velocity=100)
	
	if random.randint(0,1): cpitch = inc11(cpitch)
	if random.randint(0,1): cdur = inc11(cdur)
	
	totaldur = totaldur + len

midi.update_time(0)
midi.end_of_track()

# track 2 - bass
random.seed()
cpitch, camp, cdur, totaldur, octdev = 0, 0, 0, 0, 0
basepitch = 60 - 12 - 12 # two octaves down
midi.update_time(new_time=0, relative=0)
midi.start_of_track(1)

while totaldur < (192 * generate):
	len = basedur * (rsix[cdur] + 1)
	pitch = basepitch + rsix[cpitch]

	midi.update_time(0)
	midi.note_on(channel=0, note=pitch, velocity=100)

	midi.update_time(len)
	midi.note_off(channel=0, note=pitch, velocity=100)
	
	if random.randint(0,2): cpitch = inc11(cpitch)
	if random.randint(0,2): cdur = inc11(cdur)
	
	totaldur = totaldur + len

midi.update_time(0)
midi.end_of_track()


# track 3 - chords
random.seed()
cpitch, camp, cdur, totaldur, octdev = 0, 0, 0, 0, 0
basepitch = 60
basedur = basedur # some long chords. yum.
midi.update_time(new_time=0, relative=0)
midi.start_of_track(2)

while totaldur < (192 * generate):
	len = basedur * (inver[cdur] + 1)
	howmany = range(random.randint(2,5))
	pitches = []
	start = len
	for x in howmany:
		pitch = basepitch + inver[cpitch]
		pitches = pitches + [pitch]
		midi.update_time(start)
		start=0
		midi.note_on(channel=0, note=pitch, velocity=100)
		cpitch = inc11(cpitch)

	to = len
	for pitch in pitches:
		midi.update_time(to)
		to = 0
		midi.note_off(channel=0, note=pitch)
	
	cdur = inc11(cdur)
	totaldur = totaldur + len


midi.update_time(0)
midi.end_of_track()

midi.eof()