# coding=utf-8
'''
Created on 2016年3月9日
这是基于直连数据库的方法
图片文件名全部用.jpg，content_type="image/jpeg"
因为在2进制方式下面png,jpg可以随意切换
@author: ChenHao
'''

from pymongo.mongo_client import MongoClient

from proxy import ip_pool
from util_common import html_downloader, Constant
import threading
import uuid
import gridfs


class ImgFileMain():
    def __init__(self, userName=None, maxThread=100):
        cli = MongoClient(Constant.MONGODB_URL)
        self.db = cli.spider
        self.fs = gridfs.GridFS(cli.pictures)
        self.user = self._get_user(userName)
        self.pool = ip_pool.Pool()
        self.activeThread = 0
        self.maxThread = maxThread
        self.successed = 0
        self.failured = 0
        self.total = 0
        # last one
        self.isLast = False

    def _get_user(self, userName):
        rs_user = self.db.user.find_one({"name": userName})
        if rs_user is None:
            # 初次接入
            print(userName, "：is new for this task, Welcome!")
            rs_user = self.db.user.insert({"name": userName, "starttime": 0})
        return rs_user
    
    # 获得N个任务
    def _get_task(self, size=1):
        try:
            if self.isLast:
                return [self.db.component_original.find_one({"imgTask" : Constant.TODO}, {"_id": True, "img_url_mouser": True})]
#             rand = random.random()
            result = self.db.component_original.find({"imgTask" : Constant.TODO}).limit(size)
            if result is None:
                result = self.db.component_original.find({"imgTask" : Constant.TODO}).limit(size)
            return result
        except:
            return []
    
    # 生成图片文件名
    def _get_imgName_and_img_url_uu(self):
        uuid_str = str(uuid.uuid1())
        imgName = uuid_str.replace("-", "") + ".jpg"
        img_url_uu = Constant.IMG_URL_HEADER + imgName
        return imgName, img_url_uu
    
    def hasNext(self):
        try:
            count = self.db.component_original.find({"imgTask": Constant.TODO}).count()
            self.isLast = count == 1
            return count > 0
        except:
            return True
    
    def _save_one_result(self, _id, cont_file):
        # 保存并生成
        try:
            imgName, img_url_uu = self._get_imgName_and_img_url_uu()
            print (imgName, img_url_uu)
            self.fs.put(cont_file, content_type="image/jpeg", filename=imgName)
#             self.db.component_original.update_one({'_id': _id}, {'$set': {'imgTask': Constant.DONE, 'img_url_uu': img_url_uu, 'img_download_user': self.user["name"]}})
        except:
            None
    
    def _get_one_proxy(self):
        return self.pool.get()
    
    def _remove_one_proxy(self, proxy):
        self.pool.remove(proxy)
                
    def _on_download_success(self, _id, cont_file, proxy):
        self.activeThread -= 1
        # 检查是不是有效下载（以5KB为标准）
        if len(cont_file) < 5000:
            self._remove_one_proxy(proxy)
            self.failured += 1
        else:
            self._save_one_result(_id, cont_file)
            self.successed += 1
    
    def _on_download_error(self, e, url, proxy):
        self.activeThread -= 1
        self._remove_one_proxy(proxy)
        self.failured += 1
#         print("failed! proxy ", proxy, ", url: ", url, e)
    
    def craw(self):
        if self.maxThread > self.activeThread:
            currentTasks = self._get_task(self.maxThread - self.activeThread)    
            for task in currentTasks:
                crawer = CrawerThread(task["_id"], task["img_url_mouser"], None, self._on_download_success, self._on_download_error)
                crawer.start()
                self.activeThread += 1
                self.total += 1  
    
    def statistic(self):
        return self.successed, self.failured, self.activeThread, self.total


class CrawerThread(threading.Thread):  
    def __init__(self, _id, img_url_mouser, proxy, success, error):
        threading.Thread.__init__(self)
        self.downloader = html_downloader.HtmlDownloader()
        self._id = _id
        self.img_url_mouser = img_url_mouser
        self.proxy = proxy
        self.success = success
        self.error = error
          
    def run(self):  
        try:
            cont_file = self.downloader.download_file(self.img_url_mouser, self.proxy)
            if self.success is not None:
                self.success(self._id, cont_file, self.proxy)
        except Exception as e:
            if self.error is not None:
                self.error(e, self.img_url_mouser, self.proxy)

if __name__ == '__main__':
    task = ImgFileMain(maxThread=1)
    while task.hasNext():
        task.craw()
    
    task.close()