init: initial commit

2026-04-01 14:09:33 +08:00
commit aef2e152dc
66 changed files with 6540 additions and 0 deletions
@@ -0,0 +1,114 @@
+package service
+
+import (
+	"errors"
+	"log"
+
+	"AI-Expert-Sidebar/internal/database"
+	"AI-Expert-Sidebar/internal/models"
+)
+
+const maxResults = 5
+
+var ErrDBUnavailable = errors.New("database unavailable")
+
+// SearchResult is the DTO returned to the frontend.
+type SearchResult struct {
+	ID         uint   `json:"id"`
+	Question   string `json:"question"`
+	Answer     string `json:"answer"`
+	Category   string `json:"category"`
+	Score      int    `json:"score"` // 2=keyword, 1=question, 0=fallback
+	IsFallback bool   `json:"is_fallback"`
+}
+
+// SearchKnowledge performs fuzzy search in the active knowledge library.
+func SearchKnowledge(query string) ([]SearchResult, error) {
+	db := database.Get()
+	if db == nil {
+		return nil, ErrDBUnavailable
+	}
+	if len(query) < 1 {
+		return nil, nil
+	}
+
+	type res struct {
+		rows []SearchResult
+		err  error
+	}
+	ch := make(chan res, 1)
+
+	go func() {
+		var total int64
+		db.Model(&models.Entry{}).Count(&total)
+		if total == 0 {
+			ch <- res{[]SearchResult{}, nil}
+			return
+		}
+
+		like := "%" + query + "%"
+		var rows []models.Entry
+		err := db.Where("keyword LIKE ? OR question LIKE ?", like, like).
+			Order("updated_at DESC").Limit(maxResults).Find(&rows).Error
+		if err != nil {
+			ch <- res{nil, err}
+			return
+		}
+
+		isFallback := len(rows) == 0
+		if isFallback {
+			log.Printf("[Search] No match for %q, returning fallback", query)
+			db.Order("updated_at DESC").Limit(3).Find(&rows)
+		}
+
+		out := make([]SearchResult, 0, len(rows))
+		for _, r := range rows {
+			score := 0
+			if !isFallback {
+				if containsIgnoreCase(r.Keyword, query) {
+					score = 2
+				} else if containsIgnoreCase(r.Question, query) {
+					score = 1
+				}
+			}
+			out = append(out, SearchResult{
+				ID: r.ID, Question: r.Question, Answer: r.Answer,
+				Category: r.Category, Score: score, IsFallback: isFallback,
+			})
+		}
+		ch <- res{out, nil}
+	}()
+
+	r := <-ch
+	return r.rows, r.err
+}
+
+func containsIgnoreCase(s, sub string) bool {
+	if len(sub) == 0 {
+		return true
+	}
+	sl, subl := []rune(s), []rune(sub)
+	if len(sl) < len(subl) {
+		return false
+	}
+	for i := 0; i <= len(sl)-len(subl); i++ {
+		match := true
+		for j, c := range subl {
+			if toLower(sl[i+j]) != toLower(c) {
+				match = false
+				break
+			}
+		}
+		if match {
+			return true
+		}
+	}
+	return false
+}
+
+func toLower(r rune) rune {
+	if r >= 'A' && r <= 'Z' {
+		return r + 32
+	}
+	return r
+}