# coding=utf-8
import urllib2
import urllib
import json
import os
import ConfigParser
import codecs
import sys
from optparse import OptionParser

reload(sys)
sys.setdefaultencoding('utf-8')


class MetaData(object):
    filename = None
    fileid = None
    fsize = None
    nickname = None
    mtime = None
    key = None


class WPS(object):
    key = None
    preview_url = "https://qing.wps.cn/preview/#l/{key}"
    download_url = "https://qing.wps.cn/api/links/{key}/download?chkcode="
    metadata_url = "https://qing.wps.cn/api/skiplogin/links/{key}"
    remote_metadata = None
    local_metadata = None
    base_dir = None  # 文档输出主目录
    filedir = None  # 文档目录，以fileid命名
    metadata_filepath = None  # 元数据文件路径
    document_filepath = None  # 文档路径

    def __init__(self, key, base_dir):
        self.key = key
        self.preview_url = self.preview_url.format(key=key)
        self.download_url = self.download_url.format(key=key)
        self.metadata_url = self.metadata_url.format(key=key)
        self.base_dir = base_dir
        self.remote_metadata = self.get_remote_metadata()
        self.filedir = "%s/%s" % (self.base_dir, self.remote_metadata.fileid)
        self.metadata_filepath = "%s/metadata.ini" % self.filedir
        self.document_filepath = "%s/%s" % (self.filedir, self.remote_metadata.filename)
        if not os.path.exists(self.filedir):
            os.makedirs(self.filedir)

    def get_remote_metadata(self):
        if self.remote_metadata:
            return self.remote_metadata
        response = urllib2.urlopen(self.metadata_url)
        html = response.read()
        obj = json.loads(html)
        metadata = MetaData()
        metadata.filename = obj["lightlink"]['fname']
        metadata.fileid = obj["lightlink"]['fileid']
        metadata.fsize = obj["lightlink"]["fsize"]
        metadata.nickname = obj["lightlink"]["nickname"]
        metadata.mtime = obj["lightlink"]["mtime"]
        metadata.key = self.key
        self.remote_metadata = metadata
        return self.remote_metadata

    def get_download_file(self):
        response = urllib2.urlopen(self.download_url)
        html = response.read()
        obj = json.loads(html)
        file_url = obj['fileinfo']['url']
        urllib.urlretrieve(file_url, self.document_filepath)

    def get_local_metadata(self):
        if self.local_metadata:
            return self.local_metadata
        if not os.path.exists(self.metadata_filepath):
            return None
        else:
            cp = ConfigParser.ConfigParser()
            cp.read(self.metadata_filepath)
            metadata = MetaData()
            metadata.filename = cp.get('metadata', 'filename')
            metadata.fileid = int(cp.get('metadata', 'fileid'))
            metadata.fsize = int(cp.get('metadata', 'fsize'))
            metadata.nickname = cp.get('metadata', 'nickname')
            metadata.mtime = int(cp.get('metadata', 'mtime'))
            metadata.key = cp.get('metadata', 'key')
            self.local_metadata = metadata
            return metadata

    def check_need_update(self):
        '''
        检查是否需要更新本地文件：
        1.如果本地metadata文件不存在，需要更新
        2.如果本地metadata.mtime 与远程不一致，需要更新
        3.如果本地文档不存在，需要更新
        :return:
        '''
        if not self.get_local_metadata():
            return True
        if self.get_local_metadata().mtime <> self.get_remote_metadata().mtime:
            return True
        if not os.path.exists(self.document_filepath):
            return True
        return False

    def update_local_metadata(self):
        self.local_metadata = self.get_remote_metadata()
        md = self.local_metadata
        cp = ConfigParser.ConfigParser()
        cp.add_section("metadata")
        cp.set("metadata", "fileid", md.fileid)
        cp.set("metadata", "filename", md.filename)
        cp.set("metadata", "fsize", md.fsize)
        cp.set("metadata", "nickname", md.nickname)
        cp.set("metadata", "mtime", md.mtime)
        cp.set("metadata", "key", md.key)
        with codecs.open(self.metadata_filepath, 'w', 'utf-8') as configfile:
            cp.write(configfile)

    def run(self):
        if self.check_need_update():
            self.get_download_file()
            self.update_local_metadata()
            metadata = self.get_local_metadata()
            print "file:%s key:%s update success" % (metadata.filename, metadata.key)
        else:
            metadata = self.get_local_metadata()
            print "file:%s key:%s mtime:%s don't have to update" % (metadata.filename, metadata.key, metadata.mtime)


def usage():
    print "aaa"


def main():
    parser = OptionParser()
    parser.add_option("-k", "--key", dest="key", help="the wps document short url key")
    parser.add_option("-o", "--output", dest="output", help="the base dir to store download document file ")
    (options, args) = parser.parse_args()
    key=options.key
    output=options.output
    if key and output:
        if os.path.exists(output):
            wps_download = WPS(key=key, base_dir=output)
            wps_download.run()
        else:
            parser.error("options -o output dir %s don't exists"%output)
            parser.print_help()
    else:
        parser.print_help()
        parser.error("options -k and -o are mutually exclusive")
        exit()


if __name__ == '__main__':
    main()