#!/usr/bin/python
#-*- coding: utf-8 -*-
# The script downloads the VoxCeleb datasets and converts all files to WAV.
# Requirement: ffmpeg and wget running on a Linux system.

import argparse
import os
import subprocess
import pdb
import hashlib
import time
import glob
import tarfile
from zipfile import ZipFile
from tqdm import tqdm
from scipy.io import wavfile

## ========== ===========
## Parse input arguments 参数解析
## ========== ===========
parser = argparse.ArgumentParser(description = "VoxCeleb downloader");

parser.add_argument('--save_path', 	type=str, default="data", help='Target directory');
parser.add_argument('--user', 		type=str, default="user", help='Username');
parser.add_argument('--password', 	type=str, default="pass", help='Password');

parser.add_argument('--download', dest='download', action='store_true', help='Enable download')
parser.add_argument('--extract',  dest='extract',  action='store_true', help='Enable extract')
parser.add_argument('--convert',  dest='convert',  action='store_true', help='Enable convert')
parser.add_argument('--augment',  dest='augment',  action='store_true', help='Download and extract augmentation files')

args = parser.parse_args();

## ========== ===========
## MD5SUM
## ========== ===========
def md5(fname):

    hash_md5 = hashlib.md5()
    with open(fname, "rb") as f:
        for chunk in iter(lambda: f.read(4096), b""):
            hash_md5.update(chunk)
    return hash_md5.hexdigest()

## ========== ===========
## Download with wget
## ========== ===========
def download(args, lines):

	for line in lines:
		url 	= line.split()[0]
		md5gt 	= line.split()[1]
		outfile = url.split('/')[-1]

		## Download files
		out 	= subprocess.call('wget %s --user %s --password %s -O %s/%s'%(url,args.user,args.password,args.save_path,outfile), shell=True)
		if out != 0:
			raise ValueError('Download failed %s. If download fails repeatedly, use alternate URL on the VoxCeleb website.'%url)

		## Check MD5
		md5ck 	= md5('%s/%s'%(args.save_path,outfile))
		if md5ck == md5gt:
			print('Checksum successful %s.'%outfile)
		else:
			raise Warning('Checksum failed %s.'%outfile)

## ========== ===========
## Concatenate file parts
## ========== ===========
def concatenate(args,lines):

	for line in lines:
		infile 	= line.split()[0]
		outfile	= line.split()[1]
		md5gt 	= line.split()[2]

		## Concatenate files
		out 	= subprocess.call('cat %s/%s > %s/%s' %(args.save_path,infile,args.save_path,outfile), shell=True)

		## Check MD5
		md5ck 	= md5('%s/%s'%(args.save_path,outfile))
		if md5ck == md5gt:
			print('Checksum successful %s.'%outfile)
		else:
			raise Warning('Checksum failed %s.'%outfile)

		out 	= subprocess.call('rm %s/%s' %(args.save_path,infile), shell=True)

## ========== ===========
## Extract zip files
## ========== ===========
def full_extract(args, fname):

	print('Extracting %s'%fname)
	if fname.endswith(".tar.gz"):
		with tarfile.open(fname, "r:gz") as tar:
			tar.extractall(args.save_path)
	elif fname.endswith(".zip"):
		with ZipFile(fname, 'r') as zf:
			zf.extractall(args.save_path)

## ========== ===========
## Partially extract zip files
## ========== ===========
def part_extract(args, fname, target):

	print('Extracting %s'%fname)
	with ZipFile(fname, 'r') as zf:
		for infile in zf.namelist():
			if any([infile.startswith(x) for x in target]):
				zf.extract(infile,args.save_path)
			# pdb.set_trace()
			# zf.extractall(args.save_path)

## ========== ===========
## Convert
## ========== ===========
def convert(args):

	files 	= glob.glob('%s/voxceleb2/*/*/*.m4a'%args.save_path)
	files.sort()

	print('Converting files from AAC to WAV')
	for fname in tqdm(files):
		outfile = fname.replace('.m4a','.wav')
		out = subprocess.call('ffmpeg -y -i %s -ac 1 -vn -acodec pcm_s16le -ar 16000 %s >/dev/null 2>/dev/null' %(fname,outfile), shell=True)
		if out != 0:
			raise ValueError('Conversion failed %s.'%fname)

## ========== ===========
## Split MUSAN for faster random access
## ========== ===========
def split_musan(args):

	files = glob.glob('%s/musan/*/*/*.wav'%args.save_path)

	audlen = 16000*5
	audstr = 16000*3

	for idx,file in enumerate(files):
		fs,aud = wavfile.read(file)
		writedir = os.path.splitext(file.replace('/musan/','/musan_split/'))[0]
		os.makedirs(writedir)
		for st in range(0,len(aud)-audlen,audstr):
			wavfile.write(writedir+'/%05d.wav'%(st/fs),fs,aud[st:st+audlen])

		print(idx,file)

## ========== ===========
## Main script
## ========== ===========
if __name__ == "__main__":

	if not os.path.exists(args.save_path):
		raise ValueError('Target directory does not exist.')

	f = open('lists/fileparts.txt','r')
	fileparts = f.readlines()
	f.close()

	f = open('lists/files.txt','r')
	files = f.readlines()
	f.close()

	f = open('lists/augment.txt','r')
	augfiles = f.readlines()
	f.close()

	if args.augment:
		download(args,augfiles)
		part_extract(args,os.path.join(args.save_path,'rirs_noises.zip'),['RIRS_NOISES/simulated_rirs/mediumroom','RIRS_NOISES/simulated_rirs/smallroom'])
		full_extract(args,os.path.join(args.save_path,'musan.tar.gz'))
		split_musan(args)

	if args.download:
		download(args,fileparts)

	if args.extract:
		concatenate(args, files)
		for file in files:
			full_extract(args,os.path.join(args.save_path,file.split()[1]))
		out = subprocess.call('mv %s/dev/aac/* %s/aac/ && rm -r %s/dev' %(args.save_path,args.save_path,args.save_path), shell=True)
		out = subprocess.call('mv %s/wav %s/voxceleb1' %(args.save_path,args.save_path), shell=True)
		out = subprocess.call('mv %s/aac %s/voxceleb2' %(args.save_path,args.save_path), shell=True)

	if args.convert:
		convert(args)
		
