feat(help-center): expose public portal search

internal/handler/api/v1/article_handler.go

@@ -4,6 +4,7 @@ import (
 	"encoding/json"
 	"errors"
 	"net/http"
+	"regexp"
 	"strconv"
 	"strings"
 
@@ -75,6 +76,46 @@ func (h *ArticleHandler) PublicList(c *gin.Context) {
 	})
 }
 
+// PublicSearch returns public help-center search results for the portal search page.
+// GET /hc/:slug/:locale/search
+func (h *ArticleHandler) PublicSearch(c *gin.Context) {
+	portal, ok := h.resolvePublicPortal(c)
+	if !ok {
+		return
+	}
+
+	page, perPage, offset, ok := publicSearchPagination(c)
+	if !ok {
+		return
+	}
+	query := strings.TrimSpace(c.Query("query"))
+	if query == "" {
+		c.JSON(http.StatusOK, gin.H{"payload": []gin.H{}, "meta": gin.H{"articles_count": 0, "current_page": page}})
+		return
+	}
+
+	params := repository.ArticleSearchParams{
+		PortalID: portal.ID,
+		Query:    query,
+		Locale:   c.Param("locale"),
+		Status:   string(model.ArticleStatusPublished),
+		SortBy:   c.Query("sort"),
+		Offset:   offset,
+		Limit:    perPage,
+	}
+	articles, count, err := h.svc.Search(c.Request.Context(), params)
+	if err != nil {
+		applogger.L().Errorf("Public article search: %v", err)
+		response.AbortWithStatusError(c, http.StatusInternalServerError, response.ErrInternal, "failed to search articles")
+		return
+	}
+
+	c.JSON(http.StatusOK, gin.H{
+		"payload": publicSearchArticlePayloads(articles, portal.Slug, query),
+		"meta":    gin.H{"articles_count": count, "current_page": page},
+	})
+}
+
 // NewArticleHandler creates a new ArticleHandler.
 func NewArticleHandler(svc *service.ArticleService, portalSvc ...*service.PortalService) *ArticleHandler {
 	h := &ArticleHandler{svc: svc}
@@ -556,6 +597,23 @@ func publicArticlePagination(c *gin.Context) (int, int, int, bool) {
 	return page, perPage, offset, true
 }
 
+func publicSearchPagination(c *gin.Context) (int, int, int, bool) {
+	page := 1
+	if raw := c.Query("page"); raw != "" {
+		parsed, err := strconv.Atoi(raw)
+		if err != nil {
+			response.AbortWithStatusError(c, http.StatusBadRequest, response.ErrBadRequest, "invalid page")
+			return 0, 0, 0, false
+		}
+		if parsed > 0 {
+			page = parsed
+		}
+	}
+	perPage := 10
+	offset := (page - 1) * perPage
+	return page, perPage, offset, true
+}
+
 func (h *ArticleHandler) articleSearchParams(c *gin.Context, portalID uint, offset, limit int) (repository.ArticleSearchParams, bool) {
 	params := repository.ArticleSearchParams{
 		PortalID:     portalID,
@@ -723,6 +781,79 @@ func publicArticlePayload(article *model.Article, portalSlug string) gin.H {
 	return payload
 }
 
+func publicSearchArticlePayloads(articles []model.Article, portalSlug, query string) []gin.H {
+	payload := make([]gin.H, 0, len(articles))
+	for i := range articles {
+		payload = append(payload, publicSearchArticlePayload(&articles[i], portalSlug, query))
+	}
+	return payload
+}
+
+func publicSearchArticlePayload(article *model.Article, portalSlug, query string) gin.H {
+	if article == nil {
+		return gin.H{}
+	}
+	return gin.H{
+		"id":          article.ID,
+		"category_id": article.CategoryID,
+		"title":       article.Title,
+		"content":     publicSearchArticleSnippet(article.Content, query),
+		"link":        "/hc/" + portalSlug + "/articles/" + article.Slug,
+	}
+}
+
+var publicSearchHTMLTagPattern = regexp.MustCompile(`<[^>]*>`)
+
+func publicSearchArticleSnippet(content, query string) string {
+	plain := publicSearchPlainText(content)
+	if plain == "" {
+		return ""
+	}
+	lowerPlain := strings.ToLower(plain)
+	lowerQuery := strings.ToLower(strings.TrimSpace(query))
+	if lowerQuery != "" {
+		if idx := strings.Index(lowerPlain, lowerQuery); idx >= 0 {
+			start := idx - 110
+			if start < 0 {
+				start = 0
+			}
+			end := idx + len(query) + 110
+			if end > len(plain) {
+				end = len(plain)
+			}
+			snippet := strings.TrimSpace(plain[start:end])
+			if start > 0 {
+				snippet = "..." + snippet
+			}
+			if end < len(plain) {
+				snippet += "..."
+			}
+			return snippet
+		}
+	}
+	return publicSearchTruncate(plain, 220)
+}
+
+func publicSearchPlainText(content string) string {
+	text := publicSearchHTMLTagPattern.ReplaceAllString(content, " ")
+	replacements := []string{"#", "*", "_", "`", ">", "[", "]", "(", ")", "!"}
+	for _, old := range replacements {
+		text = strings.ReplaceAll(text, old, " ")
+	}
+	return strings.Join(strings.Fields(text), " ")
+}
+
+func publicSearchTruncate(text string, limit int) string {
+	if limit <= 0 || len(text) <= limit {
+		return text
+	}
+	cut := text[:limit]
+	if idx := strings.LastIndex(cut, " "); idx > 0 {
+		cut = cut[:idx]
+	}
+	return strings.TrimSpace(cut) + "..."
+}
+
 func publicAssociatedArticlePayloads(articles []model.Article) []gin.H {
 	payload := make([]gin.H, 0, len(articles))
 	for i := range articles {