#!/usr/bin/env python

# -*- coding: utf-8 -*-

# Copyright (C) 2012-2013 Hector Martin "marcan" <hector@marcansoft.com>

#

# This program is free software; you can redistribute it and/or modify

# it under the terms of the GNU General Public License as published by

# the Free Software Foundation, either version 2 or version 3.

#

# This program is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the

# GNU General Public License for more details.

#

# You should have received a copy of the GNU General Public License

# along with this program; if not, write to the Free Software

# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA

from _audio import *

import sys

a = AudioEngine()

a.set_mic_volume(0)

print "Sample Rate: %dHz" % a.sample_rate

print "Loading audio file..."

file = AudioFile(sys.argv[1], a.sample_rate)

print "Loaded"

a.play(file)

def build_bpms(beats):

endpos = beats[-1]

tolerance = 0.2

beats = [(beats[i], beats[i+1] - beats[i]) for i in range(len(beats)-1)]

fbeats = beats

oldlen = 0

print >>sys.stderr, "Got %d beats" % len(beats)

while oldlen != len(fbeats):

oldlen = len(fbeats)

avg = sum(l for s,l in fbeats) / len(fbeats)

fbeats = [b for b in fbeats if abs(avg-b[1]) < avg*tolerance]

print >>sys.stderr, "After filtering, %d valid beats avg %fBPM" % (len(fbeats), 60.0/avg)

off = fbeats[0][0]

error = 0

for start, length in fbeats:

beat = (start - off) / avg

ibeat = int(round(beat))

error += beat - ibeat

off += error / len(fbeats)

last = int(round((endpos - off) / avg))

last_time = off + avg * last

print >>sys.stderr, "Offset %f, %d beats" % (off, last + 1)

while off > avg:

off -= avg

last += 1

return off, last_time, last

#print "@%f=0" % off

#print "@%f=%d" % (last_time, last)

off_t = 0

beats = [(off_t, [])]

try:

while True:

v = raw_input()

t = a.song_time()

if v == "n":

off_t = beats[-1][1][-1] +beats[-1][0]

beats.append((off_t, []))

beats[-1][1].append(t - off_t)

except KeyboardInterrupt:

print "KeyboardInterrupt!"

a.shutdown()

file.close()

finally:

beat = 0

bmap = []

t = 0

for off, beatlist in beats:

if len(beatlist) < 2:

continue

first_t, last_t, last = build_bpms(beatlist)

bmap.append((off + first_t - t, beat))

bmap.append((last_t - first_t, last))

beat = 1

t = off + last_t

i = 0

last = None

t = 0

beat = 0

for i, (when, delta) in enumerate(bmap):

t += when

if i != 0 and when < last * 0.1 and delta == 1:

continue

beat += delta

print "@%f=%d" % (t, beat)

last = when

#print "@%f=%d" % (last_time, last)