import os

import sys

import subprocess

import numpy as np

import librosa

import pickle

from subprocess import call

# Gets the current directory

dir_path = os.path.dirname(os.path.realpath(__file__))

# List of options

instruments = ['violin','viola','guitar','banjo']

difficulties = ['beginner','intermediate','advanced']

hop = [512,1024]

# Saves args

term = str(sys.argv[1])

instrument = str(sys.argv[2])

difficulty = str(sys.argv[3])

# Creates new directory for music & information if not already made

if not os.path.exists("%s/music/%s" % (dir_path,term.replace(' ','-')) ):

os.makedirs("%s/music/%s" % (dir_path,term.replace(' ','-')) )

# ---------------------------------------------------------------------------------------

# Get the pitch at a time with note

def detect_pitch(y, sr, t):

index = magnitudes[:, t].argmax()

pitch = pitches[index, t]

return pitch

# Gets the energy of harmonics at a time

def get_energy(y, sr, t):

index = magnitudes[:, t].argmax()

energy = S_sal[index, t]

return energy

# ---------------------------------------------------------------------------------------

# If there isn't music for that term already, download it

if (os.path.exists(dir_path+'/music/%s/%s.mp3' % (term.replace(' ','-'),term.replace(' ','-'))) == False):

# Get the url for a term, download mp3 and information on it

for x in range(2,5):

try:

url = os.popen('timeout 30 casperjs %s/casperjs/download.js --term="%s" --attempt="%s"' % (dir_path,term,str(x))).read().split('"')[1]

except Exception as e:

print 'URL cannot be resolved - Retrying'

continue

os.system('wget --output-document="%s/music/%s/%s.mp3" "%s"' % (dir_path,term.replace(' ','-'),term.replace(' ','-'),url))

break

else:

print 'No adequate files could be attained'

exit()

# If the pickle for this term has not been generated before, generate one

if (os.path.exists(dir_path+'/music/%s/%s.pkl' % (term.replace(' ','-'),term.replace(' ','-'))) == False):

print 'Extracting notes/etc. from song'

# Returns sample rate

file_length = os.popen('mp3info -p "%S" '+dir_path+'/music/'+term.replace(' ','-')+'/'+term.replace(' ','-')+'.mp3').read()

# Load the music

y, sr = librosa.load(dir_path+'/music/%s/%s.mp3' % (term.replace(' ','-'),term.replace(' ','-')) )

# Set the hop length depending on sample rate

hop_length = min(hop, key=lambda x:abs(x-(sr / 43)))

# Separate harmonics and percussives into two waveforms

stft = librosa.stft(y)

H, P = librosa.decompose.hpss(stft) #, margin=(5,1))

y_harmonic = librosa.core.istft(H)

y_percussive = librosa.core.istft(P)

# Estimates harmonic energy

S = np.abs(librosa.stft(y))

freqs = librosa.core.fft_frequencies(sr)

harms = [1, 2, 3, 4]

weights = [1.0, 0.5, 0.33, 0.25]

S_sal = librosa.salience(S, freqs, harms, weights, fill_value=0)

# Estimates of a possible beat to be filtered later, and it's timing, magnitude

onset_env = librosa.onset.onset_strength(y=y, sr=sr,aggregate=np.median)

tempo, beat_frames = librosa.beat.beat_track(onset_envelope=onset_env,hop_length=hop_length,y=y_harmonic,sr=sr,tightness=0.1)

timing = librosa.frames_to_time(beat_frames)

pitches, magnitudes = librosa.core.piptrack(y=y_harmonic, sr=sr, n_fft=(hop_length*4), hop_length=hop_length, threshold=0.1)

# Notes are the corresponding to the timing variable to be plotted -> sent to pickle

notes,pick,mags,freq,harm = [],[],[],[],[]

for x in range(0,len(beat_frames)):

try:

freq.append(detect_pitch(y_harmonic, sr, beat_frames[x]))

harm.append(get_energy(y_harmonic, sr, beat_frames[x]))

note = librosa.hz_to_note(detect_pitch(y_harmonic, sr, beat_frames[x]))

notes.append(note)

mags.append(magnitudes[:, beat_frames[x]].argmax())

except Exception as e:

notes.append('0')

mags.append('0')

continue

# Pickle to be used as a template

pick.extend([notes])

pick.extend([timing])

pick.extend([mags])

pick.extend([file_length])

pick.extend([tempo])

pick.extend([harm])

# Save for generate-video.py to use

with open(dir_path+'/music/%s/%s.pkl' % (term.replace(' ','-'),term.replace(' ','-')), 'wb') as fp:

pickle.dump(pick, fp)

# Ready Txt file vars. to be used for web player with microphone

freq = ','.join(map(str,freq)).replace("'","")

timing = ','.join(map(str,timing)).replace("'","")

mags = ','.join(map(str,mags)).replace("'","")

# Save for web player

with open(dir_path+'/music/%s/%s.txt' % (term.replace(' ','-'),term.replace(' ','-')),'w') as f:

f.write(freq+'\n'+timing+'\n'+mags)

# Generate the midi for merging

os.system('python midi.py "%s"' % term)

# Generates video animations depending upon instruments and difficulties - Uploads to Youtube currently

if (difficulty != 'all') and (instrument != 'all'):

if (os.path.exists(dir_path+'/videos/%s-%s-%s.mp4' % (term.replace(' ','-'),instrument,difficulty)) == False):

os.system('python generate-video.py "%s" "%s" "%s"' % (term,instrument,difficulty))

elif (difficulty == 'all') and (instrument == 'all'):

for x in range(0,len(instruments)):

for y in range(0,len(difficulties)):

if (os.path.exists(dir_path+'/videos/%s-%s-%s.mp4' % (term.replace(' ','-'),instruments[x],difficulties[y])) == False):

os.system('python generate-video.py "%s" "%s" "%s"' % (term,instruments[x],difficulties[y]))

elif (difficulty == 'all') and (instrument != 'all'):

for y in range(0,len(difficulties)):

if (os.path.exists(dir_path+'/videos/%s-%s-%s.mp4' % (term.replace(' ','-'),instrument,difficulties[y])) == False):

os.system('python generate-video.py "%s" "%s" "%s"' % (term,instrument,difficulties[y]))

elif (difficulty != 'all') and (instrument == 'all'):

for y in range(0,len(instruments)):

if (os.path.exists(dir_path+'/videos/%s-%s-%s.mp4' % (term.replace(' ','-'),instruments[y],difficulty)) == False):

os.system('python generate-video.py "%s" "%s" "%s"' % (term,instruments[y],difficulty))