huashijie_go/pkg/huashijie_api.go

package huashijie_api

import (
	"encoding/json"
	"fmt"
	"io"
	"log"
	"math/rand"
	"net/http"
	"os"
	"strconv"
	"strings"
	"time"
)

var XIAOMI_MODELS = []string{
	"2107119DC",
	"23116PN5BC",
	"23124RN87C",
	"24031PN0DC",
	"24072PX77C",
	"24074RPD2C",
	"M1804E4A",
	"M1810E5GG",
	"M2001J1C",
	"M2002J9E",
	"MDE5",
}

var Logger = log.New(os.Stdout, "[huashijie_api] ", log.Ldate|log.Ltime|log.Lmsgprefix)

func EnsureConnection(client http.Client) {
	// https://app.huashijie.art/api/update/checkUpdate
	req, err := http.NewRequest("GET", "https://app.huashijie.art/api/update/checkUpdate", nil)
	if err != nil {
		panic(err)
	}
	req.Header.Add("Referer", "https://app.huashijie.art/")
	req.Header.Add("User-Agent", "Dalvik/2.1.0 (Linux; U; Android 9; MI 8 SE MIUI/V12.0.2.0.PEBCNXM)")

	resp, err := client.Do(req)

	if err != nil {
		panic(err)
	}
	defer resp.Body.Close()
	body, err := io.ReadAll(resp.Body)
	if err != nil {
		panic(err)
	}
	text := string(body)
	Logger.Println(text)
	if !strings.Contains(text, "update_ver_code") {
		panic("NotImplementedError: " + text)
	}

	// 125277547
	body, r_status := GetWorkDetailResponse(client, "125277547")

	if r_status != 200 {
		Logger.Println("HTTP status code:", r_status, "body:", string(body))
		panic("HTTP status code: " + strconv.Itoa(r_status))
	}

	var r_json map[string]interface{}

	if err := json.Unmarshal(body, &r_json); err != nil {
		Logger.Println("failed to parse JSON:", string(body), "error:", err)
		panic("failed to parse JSON: " + string(body))
	}

	// check if 'status' in r_json
	if status, ok := r_json["status"]; ok {
		switch status := status.(type) {
		case float64:
			if status == 1 {
				// OK
				Logger.Println("len(body):", len(body), "->", string(body[:256]), "...OK")
				return
			}
		}
	}
	Logger.Println("JSON:", string(body))
	panic("assertion failed: status == 1")
}

var cur_fake_user_id = -1
var cur_fake_user_left = time.Now()

func GetWorkDetailResponse(client http.Client, work_id string) ([]byte, int) {
	endpoint := "https://app.huashijie.art/"
	if os.Getenv("HSJ_ENDPOINT") == "pandapaint" {
		endpoint = "https://api.pandapaint.net/"
	}
	req, err := http.NewRequest("GET", endpoint+"api/work/detailV2", nil)
	if err != nil {
		panic(err)
	}

	visitorId := "-1"
	token := ""
	if os.Getenv("HSJ_USERID") != "" {
		visitorId = os.Getenv("HSJ_USERID")
		if visitorId == "random" {
			if cur_fake_user_left.Before(time.Now()) { // rotate [1, 15] minutes
				cur_fake_user_left = time.Now().Add(time.Duration(rand.Intn(15)) * time.Minute)
				// random [30000000, 40000000]
				cur_fake_user_id = rand.Intn(40000000-30000000) + 30000000
			}
			visitorId = fmt.Sprintf("%d", cur_fake_user_id)
		}

		// fake token = md5(visitorId + "huashijie")
		// md5hash := md5.New()
		// md5hash.Write([]byte(visitorId + "huashijie"))
		// token = fmt.Sprintf("%x", md5hash.Sum(nil))

		Logger.Println("USERID:", visitorId, "token:", token, "left", time.Until(cur_fake_user_left))
	}

	p := ""
	p += "visitorId=" + visitorId
	p += "&workId=" + work_id
	p += "&cur_user_id=" + visitorId
	p += "&platform=android"
	os_version := rand.Intn(34-28) + 28
	p += fmt.Sprintf("&os_version=%d", os_version)

	if os.Getenv("HSJ_ENDPOINT") == "pandapaint" {
		p += "&version_code=168"
	} else {
		p += "&version_code=241"
	}

	p += "&device_brand=xiaomi"
	device_model := XIAOMI_MODELS[rand.Intn(len(XIAOMI_MODELS))]
	p += "&device_model=" + device_model
	p += "&token=" + token

	if os.Getenv("HSJ_ENDPOINT") == "pandapaint" {
		p += "&channel=Panda.main"
	} else {
		p += "&channel=main"
	}

	headers := map[string][]string{
		"Referer":    {endpoint},
		"User-Agent": {"okhttp/3.12.0"},
	}
	for k, v := range headers {
		req.Header[k] = v
	}
	// req.URL.RawQuery = q.Encode()
	req.URL.RawQuery = p

	resp, err := client.Do(req)
	if err != nil {
		panic(err)
	}
	defer resp.Body.Close()
	body, err := io.ReadAll(resp.Body)
	if err != nil {
		panic(err)
	}
	return body, resp.StatusCode

}