package dataReport

import (
	"encoding/json"
	"fmt"
	"hkdj-web-server/pub/common/log"
	"hkdj-web-server/pub/redis"
	"net/http"
	"strings"
	"sync"
	"time"

	"github.com/robfig/cron/v3"
)

const (
	sdkConfigAPIProd       = "https://api.dc-server.cc/sdk/getAvailableDomainList"
	sdkConfigAPIDev        = "https://dcapi.dc-dev.cc/sdk/getAvailableDomainList"
	sdkConfigCacheKey      = "report:sdk:domain_config"
	sdkConfigCacheTTL      = 30 * time.Minute
	sdkConfigFetchInterval = "0 */10 * * * *"
)

var (
	sdkConfigAPIURL = sdkConfigAPIProd // 默认正式环境，Init时会根据RunMod覆盖
	sdkConfigCron   *cron.Cron
	sdkConfigOnce   sync.Once

	sdkConfigMu        sync.RWMutex
	sdkDomainConfig    string
	sdkConfigUpdatedAt time.Time
)

type sdkConfigResponse struct {
	Code int    `json:"code"`
	Msg  string `json:"msg"`
	Data string `json:"data"`
}

// StartSDKConfigCron 定时拉取 SDK 域名配置串，服务端只缓存并原样透传。
func StartSDKConfigCron() {
	sdkConfigOnce.Do(func() {
		if err := RefreshSDKDomainConfig(); err != nil {
			log.Error("RefreshSDKDomainConfig first run fail", log.E(err))
		}

		sdkConfigCron = cron.New(cron.WithSeconds())
		if _, err := sdkConfigCron.AddFunc(sdkConfigFetchInterval, func() {
			if err := RefreshSDKDomainConfig(); err != nil {
				log.Error("RefreshSDKDomainConfig cron fail", log.E(err))
			}
		}); err != nil {
			log.Error("StartSDKConfigCron AddFunc fail", log.E(err))
			return
		}
		sdkConfigCron.Start()
	})
}

func StopSDKConfigCron() {
	if sdkConfigCron == nil {
		return
	}
	ctx := sdkConfigCron.Stop()
	<-ctx.Done()
}

func RefreshSDKDomainConfig() error {
	data, err := fetchSDKDomainConfig(sdkConfigAPIURL, &http.Client{Timeout: 5 * time.Second})
	if err != nil {
		return err
	}
	setSDKDomainConfig(data)
	if redis.Client() == nil {
		return nil
	}
	return redis.Set(sdkConfigCacheKey, data, sdkConfigCacheTTL)
}

func GetSDKDomainConfig() string {
	if redis.Client() != nil {
		data, err := redis.Get(sdkConfigCacheKey)
		if err != nil {
			log.Error("GetSDKDomainConfig redis get fail", log.E(err))
		} else if data != nil && *data != "" {
			setSDKDomainConfig(*data)
			return *data
		}
	}

	sdkConfigMu.RLock()
	defer sdkConfigMu.RUnlock()
	return sdkDomainConfig
}

func setSDKDomainConfig(data string) {
	sdkConfigMu.Lock()
	defer sdkConfigMu.Unlock()
	sdkDomainConfig = data
	sdkConfigUpdatedAt = time.Now()
}

func fetchSDKDomainConfig(apiURL string, client *http.Client) (string, error) {
	req, err := http.NewRequest(http.MethodGet, apiURL, nil)
	if err != nil {
		return "", err
	}
	req.Header.Set("Accept", "application/json")

	resp, err := client.Do(req)
	if err != nil {
		return "", err
	}
	defer resp.Body.Close()

	if resp.StatusCode != http.StatusOK {
		return "", fmt.Errorf("sdk config http status: %d", resp.StatusCode)
	}

	var result sdkConfigResponse
	if err := json.NewDecoder(resp.Body).Decode(&result); err != nil {
		return "", err
	}
	if result.Code != 0 {
		return "", fmt.Errorf("sdk config code: %d, msg: %s", result.Code, result.Msg)
	}
	if strings.TrimSpace(result.Data) == "" {
		return "", fmt.Errorf("sdk config data is empty")
	}
	return result.Data, nil
}