package handlers

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

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

func TestAllowedCollections(t *testing.T) {
	allowed := []string{
		"bp_compliance_ce",
		"bp_compliance_gesetze",
		"bp_compliance_datenschutz",
		"bp_compliance_gdpr",
		"bp_dsfa_corpus",
		"bp_dsfa_templates",
		"bp_dsfa_risks",
		"bp_legal_templates",
		"bp_iace_libraries",
	}

	for _, c := range allowed {
		if !AllowedCollections[c] {
			t.Errorf("Expected %s to be in AllowedCollections", c)
		}
	}

	disallowed := []string{
		"bp_unknown",
		"",
		"some_random_collection",
	}

	for _, c := range disallowed {
		if AllowedCollections[c] {
			t.Errorf("Expected %s to NOT be in AllowedCollections", c)
		}
	}
}

func TestSearch_InvalidCollection_Returns400(t *testing.T) {
	gin.SetMode(gin.TestMode)

	handler := &RAGHandlers{}

	w := httptest.NewRecorder()
	c, _ := gin.CreateTestContext(w)

	body := SearchRequest{
		Query:      "test query",
		Collection: "bp_evil_collection",
		TopK:       5,
	}
	bodyBytes, _ := json.Marshal(body)
	c.Request, _ = http.NewRequest("POST", "/sdk/v1/rag/search", bytes.NewReader(bodyBytes))
	c.Request.Header.Set("Content-Type", "application/json")

	handler.Search(c)

	if w.Code != http.StatusBadRequest {
		t.Errorf("Expected 400, got %d", w.Code)
	}

	var resp map[string]interface{}
	json.Unmarshal(w.Body.Bytes(), &resp)

	errMsg, ok := resp["error"].(string)
	if !ok || errMsg == "" {
		t.Error("Expected error message in response")
	}
}

func TestSearch_WithCollectionParam_BindsCorrectly(t *testing.T) {
	// Test that the SearchRequest struct correctly binds the collection field
	body := `{"query":"DSGVO Art. 35","collection":"bp_compliance_recht","top_k":3}`
	var req SearchRequest
	err := json.Unmarshal([]byte(body), &req)
	if err != nil {
		t.Fatalf("Failed to unmarshal: %v", err)
	}

	if req.Query != "DSGVO Art. 35" {
		t.Errorf("Expected query 'DSGVO Art. 35', got '%s'", req.Query)
	}
	if req.Collection != "bp_compliance_recht" {
		t.Errorf("Expected collection 'bp_compliance_recht', got '%s'", req.Collection)
	}
	if req.TopK != 3 {
		t.Errorf("Expected top_k 3, got %d", req.TopK)
	}
}

func TestHandleScrollChunks_MissingCollection_Returns400(t *testing.T) {
	gin.SetMode(gin.TestMode)
	handler := &RAGHandlers{}

	w := httptest.NewRecorder()
	c, _ := gin.CreateTestContext(w)
	c.Request, _ = http.NewRequest("GET", "/sdk/v1/rag/scroll", nil)

	handler.HandleScrollChunks(c)

	if w.Code != http.StatusBadRequest {
		t.Errorf("Expected 400, got %d", w.Code)
	}

	var resp map[string]interface{}
	json.Unmarshal(w.Body.Bytes(), &resp)
	if resp["error"] == nil {
		t.Error("Expected error message in response")
	}
}

func TestHandleScrollChunks_InvalidCollection_Returns400(t *testing.T) {
	gin.SetMode(gin.TestMode)
	handler := &RAGHandlers{}

	w := httptest.NewRecorder()
	c, _ := gin.CreateTestContext(w)
	c.Request, _ = http.NewRequest("GET", "/sdk/v1/rag/scroll?collection=bp_evil_collection", nil)

	handler.HandleScrollChunks(c)

	if w.Code != http.StatusBadRequest {
		t.Errorf("Expected 400, got %d", w.Code)
	}
}

func TestHandleScrollChunks_InvalidLimit_Returns400(t *testing.T) {
	gin.SetMode(gin.TestMode)
	handler := &RAGHandlers{}

	w := httptest.NewRecorder()
	c, _ := gin.CreateTestContext(w)
	c.Request, _ = http.NewRequest("GET", "/sdk/v1/rag/scroll?collection=bp_compliance_ce&limit=abc", nil)

	handler.HandleScrollChunks(c)

	if w.Code != http.StatusBadRequest {
		t.Errorf("Expected 400, got %d", w.Code)
	}
}

func TestHandleScrollChunks_NegativeLimit_Returns400(t *testing.T) {
	gin.SetMode(gin.TestMode)
	handler := &RAGHandlers{}

	w := httptest.NewRecorder()
	c, _ := gin.CreateTestContext(w)
	c.Request, _ = http.NewRequest("GET", "/sdk/v1/rag/scroll?collection=bp_compliance_ce&limit=-5", nil)

	handler.HandleScrollChunks(c)

	if w.Code != http.StatusBadRequest {
		t.Errorf("Expected 400, got %d", w.Code)
	}
}

func TestSearch_EmptyCollection_IsAllowed(t *testing.T) {
	// Empty collection should be allowed (falls back to default in the handler)
	body := `{"query":"test"}`
	var req SearchRequest
	err := json.Unmarshal([]byte(body), &req)
	if err != nil {
		t.Fatalf("Failed to unmarshal: %v", err)
	}

	if req.Collection != "" {
		t.Errorf("Expected empty collection, got '%s'", req.Collection)
	}

	// Empty string is not in AllowedCollections, but the handler
	// should skip validation for empty collection
}