from __future__ import with_statement
__version__ = '0.31'
__license__ = 'MIT'

import re
import os
import sys
import finalseg
import time
import tempfile
import marshal
from math import log
import random
import threading
from functools import wraps

DICTIONARY = "dict.txt"
DICT_LOCK = threading.RLock()
trie = None # to be initialized
FREQ = {}
min_freq = 0.0
total =0.0
user_word_tag_tab={}
initialized = False

def gen_trie(f_name):
    lfreq = {}
    trie = {}
    ltotal = 0.0
    with open(f_name, 'rb') as f:
        lineno = 0 
        for line in f.read().rstrip().decode('utf-8').split('\n'):
            lineno += 1
            try:
                word,freq,_ = line.split(' ')
                freq = float(freq)
                lfreq[word] = freq
                ltotal+=freq
                p = trie
                for c in word:
                    if not c in p:
                        p[c] ={}
                    p = p[c]
                p['']='' #ending flag
            except ValueError, e:
                print >> sys.stderr, f_name, ' at line', lineno, line
                raise e
    return trie, lfreq,ltotal

def initialize(*args):
    global trie, FREQ, total, min_freq, initialized
    if len(args)==0:
        dictionary = DICTIONARY
    else:
        dictionary = args[0]
    with DICT_LOCK:
        if initialized:
            return
        if trie:
            del trie
            trie = None
        _curpath=os.path.normpath( os.path.join( os.getcwd(), os.path.dirname(__file__) )  )

        abs_path = os.path.join(_curpath,dictionary)
        print >> sys.stderr, "Building Trie..., from " + abs_path
        t1 = time.time()
        if abs_path == os.path.join(_curpath,"dict.txt"): #defautl dictionary
            cache_file = os.path.join(tempfile.gettempdir(),"jieba.cache")
        else: #customer dictionary
            cache_file = os.path.join(tempfile.gettempdir(),"jieba.user."+str(hash(abs_path))+".cache")

        load_from_cache_fail = True
        if os.path.exists(cache_file) and os.path.getmtime(cache_file)>os.path.getmtime(abs_path):
            print >> sys.stderr, "loading model from cache " + cache_file
            try:
                trie,FREQ,total,min_freq = marshal.load(open(cache_file,'rb'))
                load_from_cache_fail = False
            except:
                load_from_cache_fail = True

        if load_from_cache_fail:
            trie,FREQ,total = gen_trie(abs_path)
            FREQ = dict([(k,log(float(v)/total)) for k,v in FREQ.iteritems()]) #normalize
            min_freq = min(FREQ.itervalues())
            print >> sys.stderr, "dumping model to file cache " + cache_file
            try:
                tmp_suffix = "."+str(random.random())
                with open(cache_file+tmp_suffix,'wb') as temp_cache_file:
                    marshal.dump((trie,FREQ,total,min_freq),temp_cache_file)
                if os.name=='nt':
                    import shutil
                    replace_file = shutil.move
                else:
                    replace_file = os.rename
                replace_file(cache_file+tmp_suffix,cache_file)
            except:
                print >> sys.stderr, "dump cache file failed."
                import traceback
                print >> sys.stderr, traceback.format_exc()

        initialized = True

        print >> sys.stderr, "loading model cost ", time.time() - t1, "seconds."
        print >> sys.stderr, "Trie has been built succesfully."


def require_initialized(fn):
    global initialized,DICTIONARY

    @wraps(fn)
    def wrapped(*args, **kwargs):
        if initialized:
            return fn(*args, **kwargs)
        else:
            initialize(DICTIONARY)
            return fn(*args, **kwargs)

    return wrapped


def __cut_all(sentence):
    dag = get_DAG(sentence)
    old_j = -1
    for k,L in dag.iteritems():
        if len(L)==1 and k>old_j:
            yield sentence[k:L[0]+1]
            old_j = L[0] 
        else:
            for j in L:
                if j>k:
                    yield sentence[k:j+1]
                    old_j = j


def calc(sentence,DAG,idx,route):
    N = len(sentence)
    route[N] = (0.0,'')
    for idx in xrange(N-1,-1,-1):
        candidates = [ ( FREQ.get(sentence[idx:x+1],min_freq) + route[x+1][0],x ) for x in DAG[idx] ]
        route[idx] = max(candidates)

@require_initialized
def get_DAG(sentence):
    N = len(sentence)
    i,j=0,0
    p = trie
    DAG = {}
    while i<N:
        c = sentence[j]
        if c in p:
            p = p[c]
            if '' in p:
                if not i in DAG:
                    DAG[i]=[]
                DAG[i].append(j)
            j+=1
            if j>=N:
                i+=1
                j=i
                p=trie
        else:
            p = trie
            i+=1
            j=i
    for i in xrange(len(sentence)):
        if not i in DAG:
            DAG[i] =[i]
    return DAG


def __cut_DAG(sentence):
    DAG = get_DAG(sentence)
    route ={}
    calc(sentence,DAG,0,route=route)
    x = 0
    buf =u''
    N = len(sentence)
    while x<N:
        y = route[x][1]+1
        l_word = sentence[x:y]
        if y-x==1:
            buf+= l_word
        else:
            if len(buf)>0:
                if len(buf)==1:
                    yield buf
                    buf=u''
                else:
                    if not (buf in FREQ):
                        regognized = finalseg.cut(buf)
                        for t in regognized:
                            yield t
                    else:
                        for elem in buf:
                            yield elem
                    buf=u''
            yield l_word        
        x =y

    if len(buf)>0:
        if len(buf)==1:
            yield buf
        else:
            if not (buf in FREQ):
                regognized = finalseg.cut(buf)
                for t in regognized:
                    yield t
            else:
                for elem in buf:
                    yield elem

def cut(sentence,cut_all=False):
    if not isinstance(sentence, unicode):
        try:
            sentence = sentence.decode('utf-8')
        except UnicodeDecodeError:
            sentence = sentence.decode('gbk','ignore')
    re_han, re_skip = re.compile(ur"([\u4E00-\u9FA5a-zA-Z0-9+#&\._]+)", re.U), re.compile(ur"(\r\n|\s)", re.U)
    if cut_all:
        re_han, re_skip = re.compile(ur"([\u4E00-\u9FA5]+)", re.U), re.compile(ur"[^a-zA-Z0-9+#\n]", re.U)
    blocks = re_han.split(sentence)
    cut_block = __cut_DAG
    if cut_all:
        cut_block = __cut_all
    for blk in blocks:
        if re_han.match(blk):
            #pprint.pprint(__cut_DAG(blk))
            for word in cut_block(blk):
                yield word
        else:
            tmp = re_skip.split(blk)
            for x in tmp:
                if re_skip.match(x):
                    yield x
                elif not cut_all:
                    for xx in x:
                        yield xx
                else:
                    yield x

def cut_for_search(sentence):
    words = cut(sentence)
    for w in words:
        if len(w)>2:
            for i in xrange(len(w)-1):
                gram2 = w[i:i+2]
                if gram2 in FREQ:
                    yield gram2
        if len(w)>3:
            for i in xrange(len(w)-2):
                gram3 = w[i:i+3]
                if gram3 in FREQ:
                    yield gram3
        yield w

@require_initialized
def load_userdict(f):
    global trie,total,FREQ
    if isinstance(f, (str, unicode)):
        f = open(f, 'rb')
    content = f.read().decode('utf-8')
    line_no = 0
    for line in content.split("\n"):
        line_no+=1
        if line.rstrip()=='': continue
        tup =line.split(" ")
        word,freq = tup[0],tup[1]
        if line_no==1:
            word = word.replace(u'\ufeff',u"") #remove bom flag if it exists
        if len(tup)==3:
            add_word(word, freq, tup[2])
        else:
            add_word(word, freq)

def add_word(word, freq, tag=None):
    global FREQ, trie, total, user_word_tag_tab
    freq = float(freq)
    FREQ[word] = log(freq / total)
    if tag is not None:
        user_word_tag_tab[word] = tag.strip()
    p = trie
    for c in word:
        if not c in p:
            p[c] = {}
        p = p[c]
    p[''] = ''                  # ending flag

__ref_cut = cut
__ref_cut_for_search = cut_for_search

def __lcut(sentence):
    return list(__ref_cut(sentence,False))
def __lcut_all(sentence):
    return list(__ref_cut(sentence,True))
def __lcut_for_search(sentence):
    return list(__ref_cut_for_search(sentence))


@require_initialized
def enable_parallel(processnum=None):
    global pool,cut,cut_for_search
    if os.name=='nt':
        raise Exception("jieba: parallel mode only supports posix system")
    if sys.version_info[0]==2 and sys.version_info[1]<6:
        raise Exception("jieba: the parallel feature needs Python version>2.5 ")
    from multiprocessing import Pool,cpu_count
    if processnum==None:
        processnum = cpu_count()
    pool = Pool(processnum)

    def pcut(sentence,cut_all=False):
        parts = re.compile('([\r\n]+)').split(sentence)
        if cut_all:
            result = pool.map(__lcut_all,parts) 
        else:
            result = pool.map(__lcut,parts)
        for r in result:
            for w in r:
                yield w

    def pcut_for_search(sentence):
        parts = re.compile('([\r\n]+)').split(sentence)
        result = pool.map(__lcut_for_search,parts)
        for r in result:
            for w in r:
                yield w

    cut = pcut
    cut_for_search = pcut_for_search

def disable_parallel():
    global pool,cut,cut_for_search
    if 'pool' in globals():
        pool.close()
        pool = None
    cut = __ref_cut
    cut_for_search = __ref_cut_for_search

def set_dictionary(dictionary_path):
    global initialized, DICTIONARY
    with DICT_LOCK:
        abs_path = os.path.normpath( os.path.join( os.getcwd(), dictionary_path )  )
        if not os.path.exists(abs_path):
            raise Exception("jieba: path does not exists:" + abs_path)
        DICTIONARY = abs_path
        initialized = False

def get_abs_path_dict():
    _curpath=os.path.normpath( os.path.join( os.getcwd(), os.path.dirname(__file__) )  )
    abs_path = os.path.join(_curpath,DICTIONARY)
    return abs_path

def tokenize(unicode_sentence,mode="default"):
    #mode ("default" or "search")
    if not isinstance(unicode_sentence, unicode):
        raise Exception("jieba: the input parameter should  unicode.")
    start = 0 
    if mode=='default':
        for w in cut(unicode_sentence):
            width = len(w)
            yield (w,start,start+width)
            start+=width
    else:
        for w in cut(unicode_sentence):
            width = len(w)
            if len(w)>2:
                for i in xrange(len(w)-1):
                    gram2 = w[i:i+2]
                    if gram2 in FREQ:
                        yield (gram2,start+i,start+i+2)
            if len(w)>3:
                for i in xrange(len(w)-2):
                    gram3 = w[i:i+3]
                    if gram3 in FREQ:
                        yield (gram3,start+i,start+i+3)
            yield (w,start,start+width)
            start+=width

