package main

import (
 "bytes"
 "fmt"
 "github.com/PuerkitoBio/goquery"
 "log"
 "net/http"
 "runtime"
 "strconv"
 "sync"
)

func Scraper(page string) string {
 // Request the HTML page.
 ScrapeURL := "https://news.cnblogs.com/n/page/" + page
 client := &http.Client{}
 reqest, _ := http.NewRequest("GET", ScrapeURL, nil)
 reqest.Header.Set("Accept", "text/html,application/xhtml+xml,application/xml;q=0.9,*/*;q=0.8")
 reqest.Header.Set("Accept-Charset", "GBK,utf-8;q=0.7,*;q=0.3")
 //reqest.Header.Set("Accept-Encoding", "gzip,deflate,sdch")
 reqest.Header.Set("Accept-Language", "zh-CN,zh;q=0.8")
 reqest.Header.Set("Cache-Control", "max-age=0")
 reqest.Header.Set("Connection", "keep-alive")
 reqest.Header.Set("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/68.0.3440.75 Safari/537.36")
 res, err := client.Do(reqest)
 if err != nil {
  log.Fatal(err)
 }
 defer res.Body.Close()
 if res.StatusCode != 200 {
  log.Fatalf("status code error: %d %s", res.StatusCode, res.Status)
 }

 // Load the HTML document
 doc, err := goquery.NewDocumentFromReader(res.Body)
 if err != nil {
  log.Fatal(err)
 }

 // Find the review items
 var buffer bytes.Buffer
 buffer.WriteString("**********Scraped page " + page + "**********\n")
 doc.Find(".content .news_entry").Each(func(i int, s *goquery.Selection) {
  // For each item found, get the band and title
  title := s.Find("a").Text()
  url, _ := s.Find("a").Attr("href")
  buffer.WriteString("Review " + strconv.Itoa(i) + ": " + title + "\nhttps://news.cnblogs.com" + url + "\n")
 })
 return buffer.String()
}

func main() {
 runtime.GOMAXPROCS(runtime.NumCPU())
 ch := make(chan string, 100)
 wg := &sync.WaitGroup{}
 var page string
 for i := 1; i < 101; i++ {
  wg.Add(1)
  go func(i int) {
   page = strconv.Itoa(i)
   fmt.Printf("Scraping page %s...\n", page)
   ch <- Scraper(page)
   wg.Done()
  }(i)
 }
 wg.Wait()

 //print result
 for i := 0; i < 101; i++ {
  fmt.Println(<-ch)
 }
}