from selenium import webdriver
import time
from lxml import etree
import csv

def get_driver():
	driver = webdriver.Chrome()
	return driver

def get_page_source(driver, url):
	driver.get(url)
	##函数睡眠1秒，等待网页响应和渲染
	time.sleep(1)
	page_source = driver.page_source
	return page_source

def get_xhtml(page_source):
	xhtml = etree.HTML(page_source)
	return xhtml

## 这是一个生成器函数
def parse_datas(xhtml, city):
	datas = {}
	items = xhtml.xpath('//article[@class="poi-item"]')
	for item in items:
		datas['city'] = city
		datas['hotel'] = item.xpath('.//a[@class="poi-title"]/text()')[0].strip()
        
		datas['price'] = 111#item.xpath('.//div[@class="poi-price"]/em/text()')[0].strip()

		datas['grade'] = item.xpath('.//div[@class="poi-grade"]/text()')[0].strip()
		## 部分酒店没有消费人数的信息，如果没有，返回空字符串
		try:
			datas['consumer'] = item.xpath('.//div[@class="poi-buy-num"]/text()')[0].strip()
		except IndexError:
			datas['consumer'] = ''
		datas['address'] = item.xpath('.//div[@class="poi-address"]/text()')[0].strip()
		yield datas


def save_datas(datas):
	with open('hotel.csv', 'a', encoding='GB18030', newline='') as c:
		fieldnames = ['city', 'hotel', 'price', 'grade', 'consumer', 'address']
		writer = csv.DictWriter(c, fieldnames=fieldnames)
		for data in datas:
			writer.writerow(data)

def click_next(driver, page_source, city):
	## 变量n表示爬取进度
	n = 1
	print('正在爬取', city, '酒店信息', '第%d页' % n)
	## 假如该城市只有1页的酒店数据，下面的while循环不执行
	if 'disabled next' in page_source:
		flag = False
	else:
		flag = True
	while flag:
		next_elem = driver.find_element_by_xpath('//li[@class=" next"]/a')
		next_elem.click()
		##睡眠一秒，等待下一页加载
		time.sleep(1)
		page_source = driver.page_source
		xhtml		= get_xhtml(page_source)
		datas 		= parse_datas(xhtml, city)
		save_datas(datas)
		
		n += 1
		print('正在爬取', city, '酒店信息', '第%d页' % n)
		##这个是判定条件，判断时候还存在下一页
		if 'disabled next' in page_source:
			break
		elif n >= 51:
			break
	print(city, '爬取完成', '共%d页' % n)
	driver.quit()


if __name__ == '__main__':
	city = '广州'
	url  = 'https://hotel.meituan.com/guangzhou/'
	##打开浏览器
	driver 		= get_driver()
	##爬取该城市的第一页酒店数据
	page_source = get_page_source(driver, url)
	xhtml 		= get_xhtml(page_source)
	datas 		= parse_datas(xhtml ,city)
	save_datas(datas)
	## 翻页
	click_next(driver, page_source, city)