package playletser

import (
	"fmt"
	"net/url"
	"path"
	"strings"
	"sync"
	"time"
	"videoweb/app/service/upstream"
	"videoweb/pub/common/log"

	"github.com/gin-gonic/gin"
)

const homePath = "/api/app/playlet/home"
const homeCacheTTL = 30 * time.Second

var (
	homeMu    sync.Mutex
	homeCache *HomePlayletResponse
	homeAt    time.Time
)

// FetchHome 拉取首页短剧聚合数据。
func FetchHome(c *gin.Context) (*HomePlayletResponse, error) {
	var env APIEnvelope[HomePlayletResponse]
	if err := upstream.GetPublicJSON(c, homePath, &env); err != nil {
		return nil, err
	}
	if env.Code != 200 {
		return nil, fmt.Errorf("playlet home code=%d msg=%s", env.Code, env.Msg)
	}
	return &env.Data, nil
}

// FetchHomeOrEmpty 带短缓存；失败时打日志并返回空结构，保证 SSR 页面可渲染。
func FetchHomeOrEmpty(c *gin.Context) *HomePlayletResponse {
	homeMu.Lock()
	defer homeMu.Unlock()
	if homeCache != nil && time.Since(homeAt) < homeCacheTTL {
		return cloneHome(homeCache)
	}

	data, err := FetchHome(c)
	if err != nil {
		log.Error("fetch playlet home failed", log.E(err))
		if homeCache != nil {
			return cloneHome(homeCache)
		}
		return &HomePlayletResponse{}
	}
	if data == nil {
		if homeCache != nil {
			return cloneHome(homeCache)
		}
		return &HomePlayletResponse{}
	}
	data.SeoInfo.Normalize()
	homeCache = data
	homeAt = time.Now()
	return cloneHome(homeCache)
}

func cloneHome(src *HomePlayletResponse) *HomePlayletResponse {
	if src == nil {
		return &HomePlayletResponse{}
	}
	out := *src
	if src.Announcements != nil {
		out.Announcements = append([]AnnouncementItem(nil), src.Announcements...)
	}
	if src.HomeBannerData != nil {
		out.HomeBannerData = append([]HomeBannerData(nil), src.HomeBannerData...)
	}
	if src.HomeTodayUpdateData != nil {
		out.HomeTodayUpdateData = append([]CommonData(nil), src.HomeTodayUpdateData...)
	}
	if src.HomeCategoryData != nil {
		out.HomeCategoryData = make([]HomeCategoryData, len(src.HomeCategoryData))
		for i, cat := range src.HomeCategoryData {
			out.HomeCategoryData[i] = cat
			if cat.List != nil {
				out.HomeCategoryData[i].List = append([]CommonData(nil), cat.List...)
			}
		}
	}
	if src.HomeRecommendThemes != nil {
		out.HomeRecommendThemes = append([]HomeRecommendTheme(nil), src.HomeRecommendThemes...)
	}
	if src.SeoInfo.Keywords != nil {
		out.SeoInfo.Keywords = append([]string(nil), src.SeoInfo.Keywords...)
	}
	return &out
}

// ActiveHomeBanners 过滤未启用项，保留接口返回顺序。
func ActiveHomeBanners(list []HomeBannerData) []HomeBannerData {
	if len(list) == 0 {
		return list
	}
	out := make([]HomeBannerData, 0, len(list))
	for _, item := range list {
		if !item.Status {
			continue
		}
		item.URL = normalizeBannerURL(item.URL)
		out = append(out, item)
	}
	return out
}

// normalizeBannerURL 站内页面链接补尾斜杠，避免后台漏填 "/" 时每次点击都多一次 301。
// 外链、协议相对地址、带扩展名的文件路径保持原样。
func normalizeBannerURL(raw string) string {
	raw = strings.TrimSpace(raw)
	if !strings.HasPrefix(raw, "/") || strings.HasPrefix(raw, "//") {
		return raw
	}
	u, err := url.Parse(raw)
	if err != nil || u.Path == "" || strings.HasSuffix(u.Path, "/") {
		return raw
	}
	if strings.Contains(path.Base(u.Path), ".") {
		return raw
	}
	u.Path += "/"
	return u.String()
}