export.go

package main

import (
	"crypto/sha1"
	"encoding/hex"
	"fmt"
	"io"
	"log"
	"net/http"
	"net/url"
	"os"
	"strconv"
	"strings"

	"github.com/valyala/fastjson"

	"github.com/orzogc/fake115uploader/cipher"
)

// 根据pickcode获取blockhash
func getBlockHash(c *cipher.RsaCipher, pickCode, fileID string) (blockHash string, e error) {
	defer func() {
		if err := recover(); err != nil {
			e = fmt.Errorf("getBlockHash() error: %v", err)
		}
	}()

	text, err := c.Encrypt([]byte(fmt.Sprintf(`{"pickcode":"%s"}`, pickCode)))
	checkErr(err)
	form := url.Values{}
	form.Set("data", string(text))
	req, err := http.NewRequest(http.MethodPost, downloadURL, strings.NewReader(form.Encode()))
	checkErr(err)
	req.Header.Set("Content-Type", "application/x-www-form-urlencoded")
	req.Header.Set("User-Agent", userAgent)
	req.Header.Set("Cookie", config.Cookies)
	resp, err := doRequest(req)
	checkErr(err)
	defer resp.Body.Close()

	body, err := io.ReadAll(resp.Body)
	checkErr(err)
	if *verbose {
		log.Printf("获取下载地址的响应为 %s", string(body))
	}
	var p fastjson.Parser
	v, err := p.ParseBytes(body)
	checkErr(err)
	if !v.GetBool("state") {
		panic(fmt.Errorf("获取pickcode为 %s 的文件的下载地址失败，响应是 %s", pickCode, string(body)))
	}

	text, err = c.Decrypt(v.GetStringBytes("data"))
	checkErr(err)
	if *verbose {
		log.Printf("下载信息的data为 %s", string(text))
	}
	v, err = p.ParseBytes(text)
	checkErr(err)
	fileURL := string(v.GetStringBytes(fileID, "url", "url"))
	if *verbose {
		log.Printf("下载地址是：%s", fileURL)
	}

	req, err = http.NewRequest(http.MethodGet, fileURL, nil)
	checkErr(err)
	req.Header.Set("User-Agent", userAgent)
	req.Header.Set("Cookie", config.Cookies)
	req.Header.Set("Range", "bytes=0-131071")
	resp, err = doRequest(req)
	checkErr(err)
	defer resp.Body.Close()
	body, err = io.ReadAll(resp.Body)
	checkErr(err)
	data := sha1.Sum(body)
	blockHash = hex.EncodeToString(data[:])

	return blockHash, nil
}

// 导出115 hashlink到指定文本文件
func exportHashLink() (e error) {
	defer func() {
		if err := recover(); err != nil {
			e = fmt.Errorf("exportHashLink() error: %v", err)
		}
	}()

	fileURL := fmt.Sprintf(listFileURL, config.CID, 20)
	v, err := getURLJSON(fileURL)
	checkErr(err)
	path := v.GetArray("path")
	if string(path[len(path)-1].GetStringBytes("cid")) != strconv.FormatUint(config.CID, 10) {
		panic(fmt.Errorf("cid %d 不正确", config.CID))
	}
	count := v.GetUint("count")

	fileURL = fmt.Sprintf(listFileURL, config.CID, count)
	v, err = getURLJSON(fileURL)
	checkErr(err)
	data := v.GetArray("data")
	if len(data) == 0 {
		panic(fmt.Errorf("无法获取cid为 %d 的文件夹下的文件列表", config.CID))
	}

	f, err := os.OpenFile(*outputFile, os.O_WRONLY|os.O_APPEND|os.O_CREATE, 0644)
	checkErr(err)
	defer f.Close()

	key, err := cipher.NewRsaKey()
	checkErr(err)
	c := cipher.NewRsaCipher(key)
	for _, file := range data {
		filename := string(file.GetStringBytes("n"))
		fileSize := file.GetUint64("s")
		totalHash := string(file.GetStringBytes("sha"))
		pickCode := string(file.GetStringBytes("pc"))
		fileID := string(file.GetStringBytes("fid"))

		log.Printf("正在获取 %s 的115 hashlink", filename)

		blockHash, err := getBlockHash(c, pickCode, fileID)
		if err != nil {
			log.Printf("无法获取 %s 的blockhash，出现错误：%v", filename, err)
			continue
		}

		hashLink := linkPrefix + filename + "|" + strconv.FormatUint(fileSize, 10) + "|" + strings.ToUpper(totalHash) + "|" + strings.ToUpper(blockHash)
		_, err = f.WriteString(hashLink + "\n")
		if err != nil {
			log.Printf("将115 hashlink写入 %s 出现错误：%v", *outputFile, err)
			continue
		}
	}

	return nil
}