#!/usr/bin/env python
#-*- coding: UTF-8 -*-

from tagger import *
from ApeTag import *
import os,re,time

##############  for Lyrics3v*  ###############

def seekToLyricsEnd(f):
	f.seek(-128-9,os.SEEK_END)
	buf=f.read(9)
	if(buf != "LYRICS200" and buf != "LYRICSEND"):
		f.seek(-9,os.SEEK_END)
		buf=f.read(9)
	if(buf == "LYRICS200" or buf == "LYRICSEND"):
		#f.seek(-9,os.SEEK_CUR)
		if(buf == "LYRICS200"):
			return 2
		elif(buf == "LYRICSEND"):
			return 1
	return 0

def readV1(f):
	if(seekToLyricsEnd(f)==1):
		f.seek(-5100-9-11,os.SEEK_CUR)
		buf=f.read(5100+11)
		start=buf.find("LYRICSBEGIN")
		return buf[start+11:]
	return None

def readV2(f):
	if(seekToLyricsEnd(f)==2):
		f.seek(-9-6,os.SEEK_CUR)
		size=int(f.read(6))
		f.seek(-size-6,os.SEEK_CUR)
		buf=f.read(11)
		if(buf == "LYRICSBEGIN"):
			buf=f.read(size-11)
			tags=[]
			while buf!= '':
				tag=buf[:3]
				length=int(buf[3:8])
				content=buf[8:8+length]
				buf=buf[8+length:]
				tags.append({'id':tag,'value':content})
			return tags #to get the lyrics use [tag['value'] for tag in tags if tag['id']=='LYR'][0]
	return None

def modify(filename,lrc=None,_type=2):
	f=open(filename,"rb+")#file must be opened with r+ mode
	f.seek(-128,os.SEEK_END)
	buf=f.read(3)
	id3=""
	if buf == "TAG":#exist id3
		id3="TAG"+f.read(125)
	ty=seekToLyricsEnd(f)
	#move the cursor to the right position
	if ty==1:#Lyrics3v1
		f.seek(-5100-9-11,os.SEEK_CUR)
		buf=f.read(5100+11)
		start=buf.find("LYRICSBEGIN")
		f.seek(-5111+start,os.SEEK_CUR)
	elif ty==2:#Lyrics3v2
		f.seek(-9-6,os.SEEK_CUR)
		size=int(f.read(6))
		f.seek(-size-6,os.SEEK_CUR)
	elif len(id3)>0:
		f.seek(-128,os.SEEK_END)
	else:
		f.seek(0,os.SEEK_END)
	if lrc != None:#if write the lyrics tag, else write nothing
		f.write("LYRICSBEGIN")
		if( _type==1):#Lyrics3v1
			f.write(lrc)
			f.write("LYRICSEND")
		else:
			f.write("IND00003110")#Something like flags
			length="00000%d" % len(lrc)
			f.write("LYR%s" % (length[len(length)-5:]))
			f.write(lrc)
			length="000000%d" % (11+11+8+len(lrc))
			f.write("%sLYRICS200" % (length[len(length)-6:]))
	if len(id3)>0:#rewrite id3
		f.write(id3)
	f.truncate()
	f.close()

##############  for ID3v2  ###############

def extractUslt(filename):
	tag=getUslt(ID3v2(filename))
	if tag:
		enc='\x03'
		lang=tag.language
		desc=tag.shortcomment
		lrc=tag.longcomment
		return {"enc":enc,"lang":lang,"desc":desc,"text":lrc}
	return None

def addUslt(filename,uslt):
	mp3=ID3v2(filename)
	tag=getUslt(mp3)
	if tag:
		mp3.frames.remove(tag)
	tag=mp3.new_frame("USLT")
	tag.encoding='utf_8'#'utf-8' doesn't work it's a pytagger problem
	tag.language=uslt['lang']
	tag.shortcomment=uslt['desc']
	tag.longcomment=uslt['text']
	mp3.frames.append(tag)
	mp3.commit()

def getUslt(id3):
	for tag in id3.frames:
		if tag.fid == "USLT":
			return tag
	return None

##############  for ApeTag  ###############

def getApeLyrics(filename):
	try:
		lrc=getapefields(filename)['Lyrics'][0]
	except:
		return None
	else:
		return lrc

def addApeLyrics(filename,lrc):
	createape(filename,{'Lyrics':lrc})
	
def removeApeLyrics(filename):
	fields=getapefields(filename)
	if fields.has_key('Lyrics'):
		del fields['Lyrics']
	replaceape(filename,fields)

#############  for SYLT  ######################

def endOfString(string,utf16=False):
	if(utf16):
		pos=0
		while True:
			pos+=string[pos:].find('\x00\x00')+1
			if pos % 2 == 1:
				return pos-1
	else:
		return string.find('\x00')

def ms2timestamp(ms,utf16=False):
	mins="0%s" % int(ms/1000/60)
	sec="0%s" % int((ms/1000)%60)
	msec="0%s" % int((ms%1000)/10)
	timestamp="[%s:%s.%s]" % (mins[-2:],sec[-2:],msec[-2:])
	return timestamp

def sylt2lrc(sylt):
	utf16=bool(sylt['enc'].find('16') != -1)
	if sylt['desc'].startswith('\xff\xfe'):
		code=u'\xff\xfe'
	else:
		code=u'\xfe\xff'
	strip=lambda x: x.replace(code,'')
	lrc='\r\n'.join(["%s%s" % (ms2timestamp(ms,utf16),strip(text)) for ms,text in sylt['pieces']])
	return lrc.encode(sylt['enc'])

def extractSYLT(filename):
	tag=getSYLT(ID3v2(filename))
	if tag:
		enc=['latin_1','utf_16','utf_16_be','utf_8'][ord(tag.rawdata[0])]
		lang=tag.rawdata[1:4]
		format=tag.rawdata[4]
		ctype=tag.rawdata[5]
		raw=tag.rawdata[6:]
		utf16=bool(enc.find('16') != -1)
		pos=endOfString(raw,utf16)
		desc=raw[:pos]
		if utf16:
			pos+=1
		content=raw[pos+1:]
		del raw
		pcs=[]
		while content != "":
			pos=endOfString(content,utf16)
			text=content[:pos].decode(enc)
			if utf16:
				pos+=1
			time=content[pos+1:pos+5]
			timems=0
			for x in range(4):
				timems+=(256)**(3-x) * ord(time[x])
			pcs.append([timems,text.replace('\n','').replace('\r','').strip()])
			content=content[pos+5:]
		return {"enc":enc,"lang":lang,"ctype":ctype,"desc":desc,"pieces":pcs}
	return None

def getSYLT(id3):
	if id3.version == 2.2:
		sylt="SLT"
	else:
		sylt="SYLT"
	for tag in id3.frames:
		if tag.fid == sylt:
			return tag
	return None

def removeSYLT(filename):
	mp3=ID3v2(filename)
	sylt=getSYLT(mp3)
	if sylt:
		mp3.frames.remove(sylt)
		mp3.commit()

def stripUtf16(text):
	return ''.join([text[i] for i in range(len(text)) if i%2==0])

def lrc2list(lrc,utf16=False):
	if ord(lrc[0])==0xfe and ord(lrc[1])==0xff or ord(lrc[0])==0xff and ord(lrc[1])==0xfe:
		lrc=lrc[2:]
	if utf16:
		lrcstrip=stripUtf16(lrc)
	else:
		lrcstrip=lrc
	offset=re.findall("\[offset:([0-9]+)\]",lrcstrip)
	if offset:
		offset=int(offset[0])
	else:
		offset=0
	lines=lrcstrip.split('\r\n')
	gap=2
	if len(lines) == 1:
		lines=lrcstrip.split('\n')
		gap=1
	if len(lines) == 1:
		lines=lrcstrip.split('\r')
	ret=[]
	tot=0
	rightpos=lambda x: (x+tot)*{True:2,False:1}[utf16]
	for i in range(len(lines)):
		if lines[i].rfind(']') != -1:
			line=lines[i]
			text=line[line.rfind(']')+1:]
			text=lrc[rightpos(line.rfind("]")+1):rightpos(len(line))]
			timestamps=re.findall("\[([0-9]+):([0-9]+)[\:\.]{0,1}([0-9]*)\]",line)
			for t in timestamps:
				time=int(t[0])*1000*60
				time+=int(t[1])*1000
				if t[2] != '':
					time+=int(t[2]+'0'*(3-len(t[2])))
				time+=offset
				ret.append([time,text])
		tot+=len(lines[i])+gap
	ret.sort()
	return ret

def setSYLT(filename,lrc,lrc_enc='utf-8'):
	utf16=bool(lrc_enc.lower().startswith('utf') and lrc_enc.find('16') != -1)
	if not utf16:
		lrc=lrc.decode(lrc_enc).encode('utf-16')
		utf16=True
	lis=lrc2list(lrc,utf16)
	raw="%seng\x02\x01" % ({True:'\x01',False:'\x03'}[utf16])
	if utf16:
		raw+="Sylt written by lrcShow-II\x00".encode('utf-16')
	else:
		raw+="Sylt written by lrcShow-II\x00"
	for t,text in lis:
		if len(text)%2 != 0:
			print [ms2timestamp(t),text]
		tstr=chr(t/256/256/256)
		tstr+=chr(t/256/256%256)
		tstr+=chr(t/256%256)
		tstr+=chr(t%256)
		if utf16:
			raw+="%s\x00\x00%s" % (text,tstr)
		else:
			raw+="%s\x00%s" % (text.encode('utf-8',lrc_enc),tstr)
	mp3 = ID3v2(filename)
	tag=getSYLT(mp3)
	if tag:
		mp3.frames.remove(tag)
	if mp3.version == 2.2:
		tag=mp3.new_frame("SLT")
	else:
		tag=mp3.new_frame("SYLT")
	tag.rawdata=raw
	mp3.frames.append(tag)
	mp3.commit()



class embedLrc:
	
	def __init__(self,fileName):
		self.fileName=fileName
	
	def detectLrc(self):
	#detect order: apetag>ID3v2(uslt)>lyrics3v2>lyrics3v1>ID3v2(sylt)
		lrc=getApeLyrics(self.fileName)
		if lrc:
			return lrc.encode('utf8')
		
		lrc=extractUslt(self.fileName)
		if lrc:
			return lrc['text']
		
		f=file(self.fileName,"r")
		tags=readV2(f)
		if tags:
			lrc=[tag['value'] for tag in tags if tag['id']=='LYR'][0]
			f.close()
			return lrc
		
		lrc=readV1(f)
		f.close()
		if lrc:
			return lrc
		
		sylt=extractSYLT(self.fileName)
		if sylt:
			lrc=sylt2lrc(sylt)
			if lrc:
				return lrc
			else:
				return None
		else:
			return None
	
	def insertLrc(self,writeType,lrc):
		if(writeType=='id3v2-uslt'):
			lrc={"enc":'\x03',"lang":'chi',"desc":'',"text":lrc}
			addUslt(self.fileName,lrc)
		elif(writeType=='lyrics3v2'):
			modify(self.fileName,lrc,2)
		elif(writeType=='lyrics3v1'):
			modify(self.fileName,lrc,1)
		elif(writeType=='apetag'):
			lrc=unicode(lrc,'utf8')
			addApeLyrics(self.fileName,lrc)
		elif(writeType=='id3v2-sylt'):
			setSYLT(self.fileName,lrc,'utf-8')
	
	def deleteLrc(self,writeType):
		if(writeType=='id3v2-uslt'):
			mp3=ID3v2(self.fileName)
			uslt=getUslt(mp3)
			if uslt:
				mp3.frames.remove(uslt)
				mp3.commit()
				return True
			else:
				return False
		elif(writeType=='lyrics3v2'):
			f=file(self.fileName,"r")
			tags=readV2(f)
			f.close()
			if tags:
				modify(self.fileName,None,2)
				return True
			else:
				return False
		elif(writeType=='lyrics3v1'):
			f=file(self.fileName,"r")
			tags=readV1(f)
			f.close()
			if tags:
				modify(self.fileName,None,1)
				return True
			else:
				return False
		elif(writeType=='apetag'):
			tags=getApeLyrics(self.fileName)
			if tags:
				removeApeLyrics(self.fileName)
				return True
			else:
				return False
		elif(writeType=='id3v2-sylt'):
			mp3=ID3v2(self.fileName)
			sylt=getSYLT(mp3)
			if sylt:
				mp3.frames.remove(sylt)
				mp3.commit()
				return True
			else:
				return False