#!/usr/bin/python2.7
# _*_ coding: utf-8 _*_

"""
@Author: MarkLiu
"""

import poplib
import email
from email.parser import Parser
from email.header import decode_header
from email.utils import parseaddr


def decode_str(s):
  value, charset = decode_header(s)[0]
  if charset:
    value = value.decode(charset)
  return value


def guess_charset(msg):
  # 先从msg对象获取编码:
  charset = msg.get_charset()
  if charset is None:
    # 如果获取不到，再从Content-Type字段获取:
    content_type = msg.get('Content-Type', '').lower()
    pos = content_type.find('charset=')
    if pos >= 0:
      charset = content_type[pos + 8:].strip()
  return charset


def get_email_headers(msg):
  # 邮件的From, To, Subject存在于根对象上:
  headers = {}
  for header in ['From', 'To', 'Subject', 'Date']:
    value = msg.get(header, '')
    if value:
      if header == 'Date':
        headers['date'] = value
      if header == 'Subject':
        # 需要解码Subject字符串:
        subject = decode_str(value)
        headers['subject'] = subject
      else:
        # 需要解码Email地址:
        hdr, addr = parseaddr(value)
        name = decode_str(hdr)
        value = u'%s <%s>' % (name, addr)
        if header == 'From':
          from_address = value
          headers['from'] = from_address
        else:
          to_address = value
          headers['to'] = to_address
  content_type = msg.get_content_type()
  print 'head content_type: ', content_type
  return headers


# indent用于缩进显示:
def get_email_cntent(message, base_save_path):
  j = 0
  content = ''
  attachment_files = []
  for part in message.walk():
    j = j + 1
    file_name = part.get_filename()
    contentType = part.get_content_type()
    # 保存附件
    if file_name: # Attachment
      # Decode filename
      h = email.Header.Header(file_name)
      dh = email.Header.decode_header(h)
      filename = dh[0][0]
      if dh[0][1]: # 如果包含编码的格式，则按照该格式解码
        filename = unicode(filename, dh[0][1])
        filename = filename.encode("utf-8")
      data = part.get_payload(decode=True)
      att_file = open(base_save_path + filename, 'wb')
      attachment_files.append(filename)
      att_file.write(data)
      att_file.close()
    elif contentType == 'text/plain' or contentType == 'text/html':
      # 保存正文
      data = part.get_payload(decode=True)
      charset = guess_charset(part)
      if charset:
        charset = charset.strip().split(';')[0]
        print 'charset:', charset
        data = data.decode(charset)
      content = data
  return content, attachment_files


if __name__ == '__main__':
  # 输入邮件地址, 口令和POP3服务器地址:
  emailaddress = 'xxxxxx@163.com'
  # 注意使用开通POP，SMTP等的授权码
  password = 'xxxxxx'
  pop3_server = 'pop.163.com'

  # 连接到POP3服务器:
  server = poplib.POP3(pop3_server)
  # 可以打开或关闭调试信息:
  # server.set_debuglevel(1)
  # POP3服务器的欢迎文字:
  print server.getwelcome()
  # 身份认证:
  server.user(emailaddress)
  server.pass_(password)
  # stat()返回邮件数量和占用空间:
  messagesCount, messagesSize = server.stat()
  print 'messagesCount:', messagesCount
  print 'messagesSize:', messagesSize
  # list()返回所有邮件的编号:
  resp, mails, octets = server.list()
  print '------ resp ------'
  print resp # +OK 46 964346 响应的状态 邮件数量 邮件占用的空间大小
  print '------ mails ------'
  print mails # 所有邮件的编号及大小的编号list，['1 2211', '2 29908', ...]
  print '------ octets ------'
  print octets

  # 获取最新一封邮件, 注意索引号从1开始:
  length = len(mails)
  for i in range(length):
    resp, lines, octets = server.retr(i + 1)
    # lines存储了邮件的原始文本的每一行,
    # 可以获得整个邮件的原始文本:
    msg_content = '\n'.join(lines)
    # 把邮件内容解析为Message对象：
    msg = Parser().parsestr(msg_content)

    # 但是这个Message对象本身可能是一个MIMEMultipart对象，即包含嵌套的其他MIMEBase对象，
    # 嵌套可能还不止一层。所以我们要递归地打印出Message对象的层次结构：
    print '---------- 解析之后 ----------'
    base_save_path = '/media/markliu/Entertainment/email_attachments/'
    msg_headers = get_email_headers(msg)
    content, attachment_files = get_email_cntent(msg, base_save_path)

    print 'subject:', msg_headers['subject']
    print 'from_address:', msg_headers['from']
    print 'to_address:', msg_headers['to']
    print 'date:', msg_headers['date']
    print 'content:', content
    print 'attachment_files: ', attachment_files

  # 关闭连接:
  server.quit()