# -*- coding: utf-8 -*-
#!/usr/bin/python
#!/bin/bash

# ---------------------------------------------------------- #
# This is a script which can change background automatically #
# every time the system starts.        #
# author: Huang Zhenyang          #
# email: 745125931@qq.com         #
# ---------------------------------------------------------- #
# ----- Import ----- #
import os
import re
import urllib
import time
import socket
# --- End Import --- #

class Spider(object):
 """
 This is the spider to get the img from being
 """
 def __init__( self, img_matched_pattern_para, url_para, file_name_para ):
  """
  init function
  :param img_matched_pattern_para: the pattern to match a img
  :param url_para: url to crawler
  :param file_name_para: file name
  """
  self.img_matched_pattern = img_matched_pattern_para
  self.url = url_para
  self.file_name = file_name_para
 def get_img(self):
  """
  download the image
  :return:
  """
  html = self.get_html()
  img_pos = re.search(self.img_matched_pattern, html)
  img_page_href = self.url + img_pos.group()[6:-7] + "download"
  urllib.urlretrieve(img_page_href, self.file_name)

 def get_html(self):
  """
  return the html
  :return: page's html <type 'str'>
  """
  page = urllib.urlopen(self.url)
  html = page.read()
  return html

class Controller(object):
 """
 This is the controller to control the spider's parameters.
 """
 def __init__(self, pattern_href_para, path_para, url_para, img_max_num_para):
  """
  :param pattern_href_para: href's match pattern
  :param path_para: path to save images
  :param url_para: url
  :param img_max_num_para: max number that the
  """
  self.pattern_href = pattern_href_para
  self.path = path_para
  self.url = url_para
  self.img_max_num = img_max_num_para
  self.file_name = ""
  self.init_file_name = "0.jpg"
  self.file_extension_name = ".jpg"
 def judge(self):
  """
  judge if the number of images is grater than img_max_num.
  if true, delete all of them and then run spider, else directly run spider.
  Also, we should set the file name.
  :return:
  """
  root = None
  _dirs = None
  files = None
  for root, _dirs, files in os.walk(self.path, True):
   pass
  files_len = len(files)
  if files_len == 10:
   for i in range(0, 10):
    os.remove(root + files[i])
   self.file_name = self.path + self.init_file_name
  else:
   self.file_name = self.path + str(files_len) + self.file_extension_name
 def run_spider(self):
  """
  run spider.
  TODO: This function needs to be modified in the future which makes these two class coupling too much.
  :return:
  """
  # In case user's computer hasn't connect the internet.
  for i in range(0, 60):
   try:
    spider = Spider(self.pattern_href, self.url, self.file_name)
    spider.get_img()
    break
   except IOError as e:
    print "Connection error: %s" % e
    time.sleep(60)
    continue
   except Exception as e:
    print "Connection error: %s" % e
    time.sleep(60)
    continue
  c_path = '"file://' + self.file_name + '"' # absolute path
  # call system command to change the gnome background
  os.system('gsettings set org.gnome.desktop.background picture-uri ' + c_path)
  print "gsettings set org.gnome.desktop.background picture-uri " + c_path

if __name__ == '__main__':
 pattern_href = r'href="/photo/.*" rel="external nofollow" '
 path = '/home/hzy/图片/backgrounds/'
 url = 'https://bing.ioliu.cn/'
 img_max_num = 10
 controller = Controller(pattern_href, path, url, img_max_num)
 controller.judge()
 controller.run_spider()

[Desktop Entry]
Name=autoChangeBackgroundImg
Comment=Python Program
Exec=python /home/hzy/Script/autoChangeBackgroundImg/autoChangeBackgroundImg.py
Icon=/home/hzy/Script/autoChangeBackgroundImg/autoChangeBackgroundImg.png
Terminal=false
MultipleArgs=false
Type=Application
Categories=Application;Development;
StartupNotify=true