package weixinapi

import (
	"net/http"
	"strings"
	"sync"

	"git.rosy.net.cn/baseapi/platformapi"
	"git.rosy.net.cn/baseapi/utils"
)

const (
	prodURL = "https://api.weixin.qq.com/cgi-bin"
)

const (
	actionGetToken = "token"
)

const (
	ResponseCodeBusy    = -1
	ResponseCodeSuccess = 0
)

type TokenInfo struct {
	AccessToken string `json:"access_token"`
	ExpiresIn   int    `json:"expires_in"`
}

type ErrorInfo struct {
	ErrCode int    `json:"errcode"`
	ErrMsg  string `json:"errmsg"`
}

type API struct {
	token  string
	appID  string
	secret string
	client *http.Client
	config *platformapi.APIConfig
	locker sync.RWMutex
}

func New(appID, secret string, config ...*platformapi.APIConfig) *API {
	curConfig := platformapi.DefAPIConfig
	if len(config) > 0 {
		curConfig = *config[0]
	}
	return &API{
		appID:  appID,
		secret: secret,
		client: &http.Client{Timeout: curConfig.ClientTimeout},
		config: &curConfig,
	}
}

func (a *API) GetAppID() string {
	return a.appID
}

func (a *API) GetSecret() string {
	return a.secret
}

func (a *API) SetToken(newToken string) bool {
	curToken := a.GetToken()
	if curToken != newToken {
		a.locker.Lock()
		defer a.locker.Unlock()
		a.token = newToken
		return true
	}
	return false
}

func (a *API) GetToken() string {
	a.locker.RLock()
	defer a.locker.RUnlock()
	return a.token
}

func (a *API) AccessAPI(action string, params map[string]interface{}, body string) (retVal map[string]interface{}, err error) {
	if params != nil && body != "" {
		panic("params and body can not all non-empty")
	}
	params2 := make(map[string]interface{})
	for k, v := range params {
		params2[k] = v
	}
	if action == actionGetToken {
		params2["appid"] = a.appID
		params2["secret"] = a.secret
	} else {
		accessToken := a.GetToken()
		if accessToken == "" {
			panic("token is empty!")
		}
		params2["access_token"] = accessToken
	}
	fullURL := utils.GenerateGetURL(prodURL, action, params2)
	// baseapi.SugarLogger.Debug(fullURL)

	err = platformapi.AccessPlatformAPIWithRetry(a.client,
		func() *http.Request {
			var request *http.Request
			if body == "" {
				request, _ = http.NewRequest(http.MethodGet, fullURL, nil)
			} else {
				request, _ = http.NewRequest(http.MethodPost, fullURL, strings.NewReader(body))
			}
			request.Close = true // todo try to fix EOF error when accessing weixin api.
			return request
		},
		a.config,
		func(response *http.Response) (result string, err error) {
			jsonResult1, err := utils.HTTPResponse2Json(response)
			if err != nil {
				return platformapi.ErrLevelGeneralFail, platformapi.ErrResponseDataFormatWrong
			}
			var errInfo *ErrorInfo
			// 微信的返回值，在错误与正常情况下，结构是完全不一样的
			if errCode, ok := jsonResult1["errcode"]; ok {
				errInfo = &ErrorInfo{
					ErrCode: int(utils.MustInterface2Int64(errCode)),
					ErrMsg:  jsonResult1["errmsg"].(string),
				}
				if errInfo.ErrCode == 0 {
					retVal = jsonResult1
				}
			} else {
				retVal = jsonResult1
			}
			if retVal != nil {
				return platformapi.ErrLevelSuccess, nil
			}
			newErr := utils.NewErrorIntCode(errInfo.ErrMsg, errInfo.ErrCode)
			if errInfo.ErrCode == ResponseCodeBusy {
				return platformapi.ErrLevelRecoverableErr, newErr
			}
			return platformapi.ErrLevelCodeIsNotOK, newErr
		})
	return retVal, err
}

func (a *API) RefreshToken() (tokenInfo *TokenInfo, err error) {
	result, err := a.AccessAPI(actionGetToken, utils.Params2Map("grant_type", "client_credential"), "")
	if err != nil {
		return nil, err
	}
	tokenInfo = &TokenInfo{
		AccessToken: utils.Interface2String(result["access_token"]),
		ExpiresIn:   int(utils.MustInterface2Int64(result["expires_in"])),
	}
	// update my token too.
	a.SetToken(tokenInfo.AccessToken)
	return tokenInfo, nil
}

func (a *API) MessageTemplateSend(userOpneID, templateID, downloadURL string, miniProgram, data interface{}) (err error) {
	bodyJson := map[string]interface{}{
		"touser":      userOpneID,
		"template_id": templateID,
		"url":         downloadURL,
		"data":        data,
	}
	if downloadURL != "" {
		bodyJson["url"] = downloadURL
	}
	if miniProgram != nil {
		bodyJson["miniprogram"] = miniProgram
	}
	_, err = a.AccessAPI("message/template/send", nil, string(utils.MustMarshal(bodyJson)))
	return err
}