package kb_test

import (
	"context"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"testing"

	"chat-agent-system/internal/kb"
)

func TestReranker_MockServer(t *testing.T) {
	server := httptest.NewServer(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		if r.URL.Path != "/v1/rerank" {
			t.Errorf("unexpected path: %s", r.URL.Path)
		}
		var req struct {
			Model     string   `json:"model"`
			Query     string   `json:"query"`
			Documents []string `json:"documents"`
		}
		if err := json.NewDecoder(r.Body).Decode(&req); err != nil {
			http.Error(w, err.Error(), http.StatusBadRequest)
			return
		}

		type result struct {
			Index          int     `json:"index"`
			RelevanceScore float64 `json:"relevance_score"`
		}
		var results []result
		for i := range req.Documents {
			results = append(results, result{
				Index:          i,
				RelevanceScore: 0.95 - float64(i)*0.1,
			})
		}
		resp := map[string]any{"results": results}
		w.Header().Set("Content-Type", "application/json")
		json.NewEncoder(w).Encode(resp)
	}))
	defer server.Close()

	reranker := kb.NewReranker(server.URL, "test-key", "bge-reranker-v2-m3")
	docs := []string{
		"GB 9706.1-2020 医用电气设备安全通用要求",
		"GB/T 4208 外壳防护等级",
	}
	scores, err := reranker.Rerank(context.Background(), "医用电气安全接地", docs)
	if err != nil {
		t.Fatalf("Rerank failed: %v", err)
	}
	if len(scores) != len(docs) {
		t.Fatalf("expected %d scores, got %d", len(docs), len(scores))
	}
	if scores[0] <= scores[1] {
		t.Errorf("expected doc 0 score > doc 1 score, got %f vs %f", scores[0], scores[1])
	}
}