#!/usr/bin/env python2

import sys
import midi

CLOCK = 1000000.0

mid = midi.read_midifile(sys.argv[1])

MIDIOFF = 24

print "// Music data"
print

print "const uint16_t note_wl[] __attribute__ ((section(\".text;\"))) = {"

notes = range(0, 64)
wls = [0] + [int(CLOCK / (2 ** ((n + MIDIOFF + 1 - 69) / 12.0) * 440)) for n in notes]

print "  " + ", ".join(["0x%04x" % wl for wl in wls])

print "};"
print

data = []

channel = [0, 0, 0]
on = set()

combined = []
i = 0
for track in mid:
    i += 1
    if i == 10:
        continue
    t = 0
    for ev in track:
        combined.append([t, ev])
        t += ev.tick

combined.sort(lambda a, b: cmp(a[0], b[0]))

for i in range(0, len(combined)):
    if i < len(combined) - 1:
        combined[i][1].tick = combined[i+1][0] - combined[i][0]

tempo = 120
for ev in combined:
    if ev[1].name == "Set Tempo":
        tempo = ev[1].bpm
        break

tpb = (60.0 * 1000000.0 / float(tempo)) / mid.resolution
tpb *= 0.8

print "const int32_t ticks_per_beat = %s;" % int(tpb);
print

buf = []

for mev in (x[1] for x in combined):
    if mev.tick:
        prevon = set(on)
        restart = set()

        for ev in buf:
            if ev.name in ["Note On", "Note Off"]:
                note = ev.data[0] - MIDIOFF

                if note <= 0 or note > 63:
                    print "// RANGE"
                    continue
                
                if ev.name == "Note On":
                    on.add(note)
                    restart.add(note)
                else:
                    on.discard(note)

        tlist = list(on)
        tlist.sort()

        while len(tlist) > 3:
            del tlist[1]

        on = set(tlist)

        #print "// " + repr(tlist)

        add = list(on - prevon)

        for note in restart:
            for i in range(0, len(channel)):
                if channel[i] == note:
                    # restart channel
                    data.append((i + 1) << 6 | note)
                    break
        
        for note in prevon - on:
            for i in range(0, len(channel)):
                if channel[i] == note:
                    if len(add):
                        print "// " + str(i) + " " + str(add[0])
                        channel[i] = add[0]
                        data.append((i + 1) << 6 | add[0])
                        del add[0]
                    else:
                        channel[i] = 0
                        data.append((i + 1) << 6)
                    break
            else:
                print "// WAT"

        for note in add:
            for i in range(0, len(channel)):
                if channel[i] == 0:
                    channel[i] = note
                    data.append((i + 1) << 6 | note)
                    break
            else:
                print "// WAT"

        #print "// ->                      " + repr(channel)

        tick = mev.tick
        #print "// -- %s ticks" % tick

        while tick > 63:
            data.append(63)
            tick -= 63;

        if tick > 0:
            data.append(tick)

        buf = [mev] 
    else:
        buf.append(mev)

    if len(data) > 7000:
        break

print "const uint8_t music[] __attribute__ ((section(\".text;\"))) = {"
print "  " + ", ".join(["0x%02x" % d for d in data])
print "};"
print "// " + str(len(data)) + " bytes"