client.go

package top

import (
	"bytes"
	"fmt"
	"io"
	"net/http"
	"net/url"
	"time"

	"github.com/51h5/go-sdk-top/internal/constants"
	"github.com/51h5/go-sdk-top/internal/utils"
	jsoniter "github.com/json-iterator/go"
)

type Client struct {
	debug        bool
	checkRequest bool
	keepAlive    bool
	ua           string
	appKey       string
	secretKey    string
	signType     string
	gateway      string
	httpClient   *http.Client
}

func New(appKey, secretKey string, timeout time.Duration) (client *Client) {
	client = &Client{
		// debug:      false,
		keepAlive:    true,
		checkRequest: true,
		appKey:       appKey,
		secretKey:    secretKey,
		gateway:      kGatewayUrl,
		signType:     constants.SIGN_TYPE_MD5,
	}

	if timeout > 0 {
		client.httpClient = &http.Client{
			Timeout: timeout,
		}
	} else {
		client.httpClient = &http.Client{
			Timeout: kHttpClientTimeout,
		}
	}

	return
}

// 调用接口
// - session: 用户的授权令牌
// - target_app_key: 被调用的目标AppKey，仅当被调用的API为第三方ISV提供时有效
func (c *Client) Execute(req Request, res Response, session string) (code uint, err error) {
	if c.checkRequest {
		code, err = req.Check()
		if err != nil {
			return
		}
	}

	// 公共参数
	sv := url.Values{
		"app_key":     {c.appKey},
		"format":      {kFormat},
		"sign_method": {c.signType},
		"v":           {kApiVersion},
		"timestamp":   {time.Now().Format(kTimeFormat)},
		"partner_id":  {kPartnerId},
		// "simplify":       {"true"},
		// "session":        {session},
		// "target_app_key": {req.TargetAppKey()},
		"method": {req.Method()},
	}

	if session != "" {
		sv.Set("session", session)
	}

	if req.TargetAppKey() != "" {
		sv.Set("target_app_key", req.TargetAppKey())
	}

	if c.debug {
		fmt.Printf("[top.Execute] 公共参数: %s\n", sv.Encode())
	}

	// 业务参数
	av := req.Values()
	if c.debug {
		fmt.Printf("[top.Execute] 业务参数: %s\n", av.Encode())
	}

	// 计算签名
	sv.Set(kKeySign, c.sign(sv, av, req))

	if c.debug {
		fmt.Printf("[top.Execute] 请求地址: %s?%s\n", c.gateway, sv.Encode())
	}

	var r *http.Request
	if req.Body() == nil {
		r, err = http.NewRequest(kMethodGet, c.gateway+"?"+sv.Encode(), nil)
	} else {
		r, err = http.NewRequest(kMethodPost, c.gateway+"?"+sv.Encode(), bytes.NewReader(req.Body()))
		if err == nil {
			r.Header.Set(kHeaderContentType, kContentTypeForm)
		}
	}

	if err != nil {
		code = 997
		return
	}

	if !c.keepAlive {
		r.Header.Set(kHeaderConnection, kConnectionClose)
	}

	if c.ua != "" {
		r.Header.Set(kHeaderUserAgent, c.ua)
	}

	body, err := doRequest(c.httpClient, r)
	if err != nil {
		code = 998
		return
	}

	if c.debug {
		fmt.Printf("[top.Execute] 请求返回: %s\n", string(body))
	}

	err = parseJsonResponse(body, res)
	if err != nil {
		code = 999
		return
	}

	// XXX: 淘宝TOP接口返回结构：混乱 & 垃圾
	res.Fix()

	return
}

func (c *Client) Debug(enable bool) {
	c.debug = enable
}

func (c *Client) CheckRequest(enable bool) {
	c.checkRequest = enable
}

func (c *Client) SetKeepAlive(v bool) {
	c.keepAlive = v
}

func (c *Client) SetUserAgent(ua string) {
	if ua != "" {
		c.ua = ua
	}
}

func (c *Client) SetGateway(v string) {
	c.gateway = v
}

func (c *Client) SetSignType(v string) {
	c.signType = v
}

func (c *Client) SetHttpClient(hc *http.Client) {
	c.httpClient = hc
}

func (c *Client) sign(sysParams, apiParams url.Values, req Request) string {
	if apiParams != nil {
		for k := range apiParams {
			if apiParams.Get(k) != "" {
				sysParams.Set(k, apiParams.Get(k))
			}
		}
	}

	if c.debug {
		fmt.Printf("[top.sign] 签名串: %v\n", sysParams)
	}

	s := utils.SignToRequest(sysParams, req.Body(), c.secretKey, c.signType)

	if c.debug {
		fmt.Printf("[top.sign] 签名: %s\n", s)
	}

	return s
}

func parseJsonResponse(body []byte, res Response) error {
	return jsoniter.Unmarshal(body, res)
}

func doRequest(c *http.Client, r *http.Request) ([]byte, error) {
	res, err := c.Do(r)
	if res != nil {
		defer res.Body.Close()
	}

	if err != nil {
		return nil, err
	}

	if res.StatusCode != http.StatusOK {
		return nil, fmt.Errorf("response code %d", res.StatusCode)
	}

	bits, err := io.ReadAll(res.Body)
	if err != nil {
		return nil, err
	}

	return bits, nil
}