package kate

import (
	"context"
	"io"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"
	"time"
)

type testData struct {
	UserID int
	Name   string
}

type testSerDes struct{}

func (ts testSerDes) Serialize(w io.Writer, data testData) error {
	_, err := w.Write([]byte(strings.Join([]string{string(rune(data.UserID)), data.Name}, "|")))
	return err
}

func (ts testSerDes) Deserialize(r io.Reader, data *testData) error {
	buf, err := io.ReadAll(r)
	if err != nil {
		return err
	}
	parts := strings.Split(string(buf), "|")
	if len(parts) != 2 {
		return io.ErrUnexpectedEOF
	}
	data.UserID = int(rune(parts[0][0]))
	data.Name = parts[1]
	return nil
}

func createTestAuth() Auth[testData] {
	config := AuthConfig[testData]{
		SerDes:     testSerDes{},
		CookieName: "test_auth",
		URLPath:    "/",
		URLDomain:  "example.com",
		HTTPSOnly:  false,
		MaxAge:     time.Hour,
	}
	return New("0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef", config)
}

func TestNew(t *testing.T) {
	tests := []struct {
		name    string
		privkey string
		wantErr bool
	}{
		{
			name:    "valid hex key",
			privkey: "0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef",
			wantErr: false,
		},
		{
			name:    "invalid hex key - too short",
			privkey: "0123456789abcdef",
			wantErr: true,
		},
		{
			name:    "invalid hex key - not hex",
			privkey: "invalid_hex_key_xxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx",
			wantErr: true,
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			config := AuthConfig[testData]{
				SerDes:     testSerDes{},
				CookieName: "test",
			}

			defer func() {
				if r := recover(); r != nil {
					if !tt.wantErr {
						t.Errorf("New() panicked unexpectedly: %v", r)
					}
				} else if tt.wantErr {
					t.Errorf("New() should have panicked but didn't")
				}
			}()

			auth := New(tt.privkey, config)
			if !tt.wantErr && auth.config.CookieName != "test" {
				t.Errorf("New() failed to create auth instance properly")
			}
		})
	}
}

func TestAuth_Set(t *testing.T) {
	auth := createTestAuth()
	data := testData{UserID: 123, Name: "Alice"}

	w := httptest.NewRecorder()
	err := auth.Set(w, data)
	if err != nil {
		t.Fatalf("Set() error = %v", err)
	}

	cookies := w.Result().Cookies()
	if len(cookies) != 1 {
		t.Fatalf("Expected 1 cookie, got %d", len(cookies))
	}

	cookie := cookies[0]
	if cookie.Name != "test_auth" {
		t.Errorf("Expected cookie name 'test_auth', got %s", cookie.Name)
	}
	if cookie.Path != "/" {
		t.Errorf("Expected cookie path '/', got %s", cookie.Path)
	}
	if cookie.Domain != "example.com" {
		t.Errorf("Expected cookie domain 'example.com', got %s", cookie.Domain)
	}
	if !cookie.HttpOnly {
		t.Error("Expected cookie to be HttpOnly")
	}
	if cookie.SameSite != http.SameSiteLaxMode {
		t.Errorf("Expected SameSite to be Lax, got %v", cookie.SameSite)
	}
}

func TestAuth_Required(t *testing.T) {
	auth := createTestAuth()
	data := testData{UserID: 123, Name: "Alice"}

	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		authData, ok := auth.Get(r.Context())
		if !ok {
			t.Error("Expected to find auth data in context")
			return
		}
		if authData.UserID != 123 || authData.Name != "Alice" {
			t.Errorf("Expected UserID=123, Name=Alice, got UserID=%d, Name=%s", authData.UserID, authData.Name)
		}
		w.WriteHeader(http.StatusOK)
	})

	protectedHandler := auth.Required(handler)

	t.Run("missing cookie", func(t *testing.T) {
		req := httptest.NewRequest("GET", "/", nil)
		w := httptest.NewRecorder()

		protectedHandler.ServeHTTP(w, req)

		if w.Code != http.StatusUnauthorized {
			t.Errorf("Expected status 401, got %d", w.Code)
		}
	})

	t.Run("invalid cookie", func(t *testing.T) {
		req := httptest.NewRequest("GET", "/", nil)
		req.AddCookie(&http.Cookie{
			Name:  "test_auth",
			Value: "invalid_token",
		})
		w := httptest.NewRecorder()

		protectedHandler.ServeHTTP(w, req)

		if w.Code != http.StatusUnauthorized {
			t.Errorf("Expected status 401, got %d", w.Code)
		}
	})

	t.Run("valid cookie", func(t *testing.T) {
		setW := httptest.NewRecorder()
		if err := auth.Set(setW, data); err != nil {
			t.Fatalf("Set() error = %v", err)
		}
		cookie := setW.Result().Cookies()[0]

		req := httptest.NewRequest("GET", "/", nil)
		req.AddCookie(cookie)
		w := httptest.NewRecorder()

		protectedHandler.ServeHTTP(w, req)

		if w.Code != http.StatusOK {
			t.Errorf("Expected status 200, got %d", w.Code)
		}
	})
}

func TestAuth_Optional(t *testing.T) {
	auth := createTestAuth()
	data := testData{UserID: 123, Name: "Alice"}

	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		authData, ok := auth.Get(r.Context())
		if ok {
			if authData.UserID != 123 || authData.Name != "Alice" {
				t.Errorf("Expected UserID=123, Name=Alice, got UserID=%d, Name=%s", authData.UserID, authData.Name)
			}
		}
		w.WriteHeader(http.StatusOK)
	})

	optionalHandler := auth.Optional(handler)

	t.Run("missing cookie - should allow", func(t *testing.T) {
		req := httptest.NewRequest("GET", "/", nil)
		w := httptest.NewRecorder()

		optionalHandler.ServeHTTP(w, req)

		if w.Code != http.StatusOK {
			t.Errorf("Expected status 200, got %d", w.Code)
		}
	})

	t.Run("invalid cookie - should allow", func(t *testing.T) {
		req := httptest.NewRequest("GET", "/", nil)
		req.AddCookie(&http.Cookie{
			Name:  "test_auth",
			Value: "invalid_token",
		})
		w := httptest.NewRecorder()

		optionalHandler.ServeHTTP(w, req)

		if w.Code != http.StatusOK {
			t.Errorf("Expected status 200, got %d", w.Code)
		}
	})

	t.Run("valid cookie", func(t *testing.T) {
		setW := httptest.NewRecorder()
		if err := auth.Set(setW, data); err != nil {
			t.Fatalf("Set() error = %v", err)
		}
		cookie := setW.Result().Cookies()[0]

		req := httptest.NewRequest("GET", "/", nil)
		req.AddCookie(cookie)
		w := httptest.NewRecorder()

		optionalHandler.ServeHTTP(w, req)

		if w.Code != http.StatusOK {
			t.Errorf("Expected status 200, got %d", w.Code)
		}
	})
}

func TestAuth_Get(t *testing.T) {
	auth := createTestAuth()
	data := testData{UserID: 123, Name: "Alice"}

	t.Run("no data in context", func(t *testing.T) {
		ctx := context.Background()
		result, ok := auth.Get(ctx)
		if ok {
			t.Error("Expected Get to return false for empty context")
		}
		if result.UserID != 0 || result.Name != "" {
			t.Error("Expected zero value for missing data")
		}
	})

	t.Run("data in context", func(t *testing.T) {
		ctx := context.WithValue(context.Background(), key, data)
		result, ok := auth.Get(ctx)
		if !ok {
			t.Error("Expected Get to return true for context with data")
		}
		if result.UserID != 123 || result.Name != "Alice" {
			t.Errorf("Expected UserID=123, Name=Alice, got UserID=%d, Name=%s", result.UserID, result.Name)
		}
	})

	t.Run("wrong type in context", func(t *testing.T) {
		ctx := context.WithValue(context.Background(), key, "wrong_type")
		result, ok := auth.Get(ctx)
		if ok {
			t.Error("Expected Get to return false for wrong type in context")
		}
		if result.UserID != 0 || result.Name != "" {
			t.Error("Expected zero value for wrong type")
		}
	})
}

type failingSerDes struct {
	failSerialize   bool
	failDeserialize bool
}

func (f failingSerDes) Serialize(w io.Writer, data testData) error {
	if f.failSerialize {
		return io.ErrClosedPipe
	}
	return testSerDes{}.Serialize(w, data)
}

func (f failingSerDes) Deserialize(r io.Reader, data *testData) error {
	if f.failDeserialize {
		return io.ErrUnexpectedEOF
	}
	return testSerDes{}.Deserialize(r, data)
}

func TestAuth_Set_SerializationError(t *testing.T) {
	config := AuthConfig[testData]{
		SerDes:     failingSerDes{failSerialize: true},
		CookieName: "test_auth",
	}
	auth := New("0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef", config)

	data := testData{UserID: 123, Name: "Alice"}
	w := httptest.NewRecorder()

	err := auth.Set(w, data)
	if err == nil {
		t.Error("Expected Set to return error for serialization failure")
	}
}

func TestAuth_Required_DeserializationError(t *testing.T) {
	config := AuthConfig[testData]{
		SerDes:     failingSerDes{failDeserialize: true},
		CookieName: "test_auth",
	}
	goodAuth := createTestAuth()
	badAuth := New("0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef", config)

	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	})

	protectedHandler := badAuth.Required(handler)

	data := testData{UserID: 123, Name: "Alice"}
	setW := httptest.NewRecorder()
	if err := goodAuth.Set(setW, data); err != nil {
		t.Fatalf("Set() error = %v", err)
	}
	cookie := setW.Result().Cookies()[0]

	req := httptest.NewRequest("GET", "/", nil)
	req.AddCookie(cookie)
	w := httptest.NewRecorder()

	protectedHandler.ServeHTTP(w, req)

	if w.Code != http.StatusInternalServerError {
		t.Errorf("Expected status 500 for deserialization error, got %d", w.Code)
	}
}

func TestAuth_Optional_DeserializationError(t *testing.T) {
	config := AuthConfig[testData]{
		SerDes:     failingSerDes{failDeserialize: true},
		CookieName: "test_auth",
	}
	goodAuth := createTestAuth()
	badAuth := New("0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef", config)

	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	})

	optionalHandler := badAuth.Optional(handler)

	data := testData{UserID: 123, Name: "Alice"}
	setW := httptest.NewRecorder()
	if err := goodAuth.Set(setW, data); err != nil {
		t.Fatalf("Set() error = %v", err)
	}
	cookie := setW.Result().Cookies()[0]

	req := httptest.NewRequest("GET", "/", nil)
	req.AddCookie(cookie)
	w := httptest.NewRecorder()

	optionalHandler.ServeHTTP(w, req)

	if w.Code != http.StatusInternalServerError {
		t.Errorf("Expected status 500 for deserialization error, got %d", w.Code)
	}
}

func TestAuth_Clear(t *testing.T) {
	auth := createTestAuth()

	t.Run("clear cookie properties", func(t *testing.T) {
		w := httptest.NewRecorder()
		auth.Clear(w)

		cookies := w.Result().Cookies()
		if len(cookies) != 1 {
			t.Fatalf("Expected 1 cookie, got %d", len(cookies))
		}

		cookie := cookies[0]
		if cookie.Name != "test_auth" {
			t.Errorf("Expected cookie name 'test_auth', got %s", cookie.Name)
		}
		if cookie.Value != "" {
			t.Errorf("Expected empty cookie value, got %s", cookie.Value)
		}
		if cookie.Path != "/" {
			t.Errorf("Expected cookie path '/', got %s", cookie.Path)
		}
		if cookie.Domain != "example.com" {
			t.Errorf("Expected cookie domain 'example.com', got %s", cookie.Domain)
		}
		if cookie.MaxAge != -1 {
			t.Errorf("Expected cookie MaxAge -1, got %d", cookie.MaxAge)
		}
		if !cookie.HttpOnly {
			t.Error("Expected cookie to be HttpOnly")
		}
		if cookie.SameSite != http.SameSiteLaxMode {
			t.Errorf("Expected SameSite to be Lax, got %v", cookie.SameSite)
		}
	})
}

func TestAuth_Clear_RemovesExistingHeaders(t *testing.T) {
	auth := createTestAuth()
	data := testData{UserID: 123, Name: "Alice"}

	t.Run("clear removes existing Set-Cookie headers for same cookie", func(t *testing.T) {
		w := httptest.NewRecorder()
		
		// Set the auth cookie first
		err := auth.Set(w, data)
		if err != nil {
			t.Fatalf("Set() error = %v", err)
		}
		
		// Verify we have one Set-Cookie header
		setCookieHeaders := w.Header()["Set-Cookie"]
		if len(setCookieHeaders) != 1 {
			t.Fatalf("Expected 1 Set-Cookie header after Set(), got %d", len(setCookieHeaders))
		}
		
		// Clear the auth cookie
		auth.Clear(w)
		
		// Verify we still have only one Set-Cookie header (the clear one)
		setCookieHeaders = w.Header()["Set-Cookie"]
		if len(setCookieHeaders) != 1 {
			t.Fatalf("Expected 1 Set-Cookie header after Clear(), got %d", len(setCookieHeaders))
		}
		
		// Parse the remaining cookie to verify it's the clear cookie
		cookies := w.Result().Cookies()
		if len(cookies) != 1 {
			t.Fatalf("Expected 1 parseable cookie, got %d", len(cookies))
		}
		
		cookie := cookies[0]
		if cookie.Name != "test_auth" {
			t.Errorf("Expected cookie name 'test_auth', got %s", cookie.Name)
		}
		if cookie.MaxAge != -1 {
			t.Errorf("Expected cookie MaxAge -1, got %d", cookie.MaxAge)
		}
		if cookie.Value != "" {
			t.Errorf("Expected empty cookie value, got %s", cookie.Value)
		}
	})
	
	t.Run("clear does not affect other cookies", func(t *testing.T) {
		w := httptest.NewRecorder()
		
		// Add a different cookie manually
		otherCookie := &http.Cookie{
			Name:  "other_cookie",
			Value: "other_value",
		}
		w.Header().Add("Set-Cookie", otherCookie.String())
		
		// Set the auth cookie
		err := auth.Set(w, data)
		if err != nil {
			t.Fatalf("Set() error = %v", err)
		}
		
		// Clear the auth cookie
		auth.Clear(w)
		
		// Verify we have two cookies: the other cookie and the clear auth cookie
		cookies := w.Result().Cookies()
		if len(cookies) != 2 {
			t.Fatalf("Expected 2 cookies after Clear(), got %d", len(cookies))
		}
		
		// Find the other cookie
		var foundOtherCookie bool
		var foundClearCookie bool
		for _, cookie := range cookies {
			if cookie.Name == "other_cookie" && cookie.Value == "other_value" {
				foundOtherCookie = true
			}
			if cookie.Name == "test_auth" && cookie.MaxAge == -1 {
				foundClearCookie = true
			}
		}
		
		if !foundOtherCookie {
			t.Error("Expected to find other_cookie in response")
		}
		if !foundClearCookie {
			t.Error("Expected to find clear auth cookie in response")
		}
	})
	
	t.Run("clear works when no existing headers", func(t *testing.T) {
		w := httptest.NewRecorder()
		
		// Clear without setting first
		auth.Clear(w)
		
		// Verify we have one Set-Cookie header (the clear one)
		cookies := w.Result().Cookies()
		if len(cookies) != 1 {
			t.Fatalf("Expected 1 cookie after Clear(), got %d", len(cookies))
		}
		
		cookie := cookies[0]
		if cookie.Name != "test_auth" {
			t.Errorf("Expected cookie name 'test_auth', got %s", cookie.Name)
		}
		if cookie.MaxAge != -1 {
			t.Errorf("Expected cookie MaxAge -1, got %d", cookie.MaxAge)
		}
	})
}

func TestRemoveSetCookieHeaders(t *testing.T) {
	t.Run("removes matching cookie headers", func(t *testing.T) {
		w := httptest.NewRecorder()
		
		// Add multiple cookies
		w.Header().Add("Set-Cookie", "test_auth=value1; Path=/")
		w.Header().Add("Set-Cookie", "other_cookie=value2; Path=/")
		w.Header().Add("Set-Cookie", "test_auth=value3; Path=/; Domain=example.com")
		
		removeSetCookieHeaders(w, "test_auth")
		
		cookies := w.Result().Cookies()
		if len(cookies) != 1 {
			t.Fatalf("Expected 1 cookie after removal, got %d", len(cookies))
		}
		
		if cookies[0].Name != "other_cookie" {
			t.Errorf("Expected other_cookie to remain, got %s", cookies[0].Name)
		}
	})
	
	t.Run("handles empty headers", func(t *testing.T) {
		w := httptest.NewRecorder()
		
		removeSetCookieHeaders(w, "test_auth")
		
		cookies := w.Result().Cookies()
		if len(cookies) != 0 {
			t.Fatalf("Expected 0 cookies, got %d", len(cookies))
		}
	})
	
	t.Run("handles malformed headers", func(t *testing.T) {
		w := httptest.NewRecorder()
		
		// Add a malformed header (no = sign)
		w.Header().Add("Set-Cookie", "malformed_header")
		w.Header().Add("Set-Cookie", "test_auth=value")
		
		removeSetCookieHeaders(w, "test_auth")
		
		// The malformed header should be preserved (check raw headers)
		setCookieHeaders := w.Header()["Set-Cookie"]
		if len(setCookieHeaders) != 1 || setCookieHeaders[0] != "malformed_header" {
			t.Errorf("Expected malformed header to be preserved, got %v", setCookieHeaders)
		}
		
		// The malformed header won't be parsed into a valid cookie by Go's parser
		cookies := w.Result().Cookies()
		if len(cookies) != 0 {
			t.Errorf("Expected 0 parseable cookies (malformed header), got %d", len(cookies))
		}
	})
}

func TestAuth_Required_ClearsInvalidCookies(t *testing.T) {
	auth := createTestAuth()
	
	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	})
	protectedHandler := auth.Required(handler)

	t.Run("clears invalid cookie on decryption failure", func(t *testing.T) {
		req := httptest.NewRequest("GET", "/", nil)
		req.AddCookie(&http.Cookie{
			Name:  "test_auth",
			Value: "invalid_encrypted_value",
		})
		w := httptest.NewRecorder()

		protectedHandler.ServeHTTP(w, req)

		if w.Code != http.StatusUnauthorized {
			t.Errorf("Expected status 401, got %d", w.Code)
		}

		// Verify that a clear cookie was set
		cookies := w.Result().Cookies()
		if len(cookies) != 1 {
			t.Fatalf("Expected 1 clear cookie to be set, got %d", len(cookies))
		}

		cookie := cookies[0]
		if cookie.Name != "test_auth" {
			t.Errorf("Expected cookie name 'test_auth', got %s", cookie.Name)
		}
		if cookie.MaxAge != -1 {
			t.Errorf("Expected cookie MaxAge -1, got %d", cookie.MaxAge)
		}
	})

	t.Run("clears invalid cookie on deserialization failure", func(t *testing.T) {
		// Create a cookie with a different auth instance that will deserialize differently
		config := AuthConfig[testData]{
			SerDes:     failingSerDes{failDeserialize: true},
			CookieName: "test_auth",
		}
		goodAuth := createTestAuth()
		badAuth := New("0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef", config)

		// Set a cookie with the good auth
		data := testData{UserID: 123, Name: "Alice"}
		setW := httptest.NewRecorder()
		if err := goodAuth.Set(setW, data); err != nil {
			t.Fatalf("Set() error = %v", err)
		}
		validCookie := setW.Result().Cookies()[0]

		// Try to use it with the bad auth (will fail deserialization)
		req := httptest.NewRequest("GET", "/", nil)
		req.AddCookie(validCookie)
		w := httptest.NewRecorder()

		badAuth.Required(handler).ServeHTTP(w, req)

		if w.Code != http.StatusInternalServerError {
			t.Errorf("Expected status 500, got %d", w.Code)
		}

		// Verify that a clear cookie was set
		cookies := w.Result().Cookies()
		if len(cookies) != 1 {
			t.Fatalf("Expected 1 clear cookie to be set, got %d", len(cookies))
		}

		cookie := cookies[0]
		if cookie.Name != "test_auth" {
			t.Errorf("Expected cookie name 'test_auth', got %s", cookie.Name)
		}
		if cookie.MaxAge != -1 {
			t.Errorf("Expected cookie MaxAge -1, got %d", cookie.MaxAge)
		}
	})
}

func TestAuth_Optional_ClearsInvalidCookies(t *testing.T) {
	auth := createTestAuth()
	
	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	})
	optionalHandler := auth.Optional(handler)

	t.Run("clears invalid cookie on decryption failure and continues", func(t *testing.T) {
		req := httptest.NewRequest("GET", "/", nil)
		req.AddCookie(&http.Cookie{
			Name:  "test_auth",
			Value: "invalid_encrypted_value",
		})
		w := httptest.NewRecorder()

		optionalHandler.ServeHTTP(w, req)

		// Should continue processing (200 OK)
		if w.Code != http.StatusOK {
			t.Errorf("Expected status 200, got %d", w.Code)
		}

		// Verify that a clear cookie was set
		cookies := w.Result().Cookies()
		if len(cookies) != 1 {
			t.Fatalf("Expected 1 clear cookie to be set, got %d", len(cookies))
		}

		cookie := cookies[0]
		if cookie.Name != "test_auth" {
			t.Errorf("Expected cookie name 'test_auth', got %s", cookie.Name)
		}
		if cookie.MaxAge != -1 {
			t.Errorf("Expected cookie MaxAge -1, got %d", cookie.MaxAge)
		}
	})

	t.Run("clears invalid cookie on deserialization failure", func(t *testing.T) {
		// Create a cookie with a different auth instance that will deserialize differently
		config := AuthConfig[testData]{
			SerDes:     failingSerDes{failDeserialize: true},
			CookieName: "test_auth",
		}
		goodAuth := createTestAuth()
		badAuth := New("0123456789abcdef0123456789abcdef0123456789abcdef0123456789abcdef", config)

		// Set a cookie with the good auth
		data := testData{UserID: 123, Name: "Alice"}
		setW := httptest.NewRecorder()
		if err := goodAuth.Set(setW, data); err != nil {
			t.Fatalf("Set() error = %v", err)
		}
		validCookie := setW.Result().Cookies()[0]

		// Try to use it with the bad auth (will fail deserialization)
		req := httptest.NewRequest("GET", "/", nil)
		req.AddCookie(validCookie)
		w := httptest.NewRecorder()

		badAuth.Optional(handler).ServeHTTP(w, req)

		if w.Code != http.StatusInternalServerError {
			t.Errorf("Expected status 500, got %d", w.Code)
		}

		// Verify that a clear cookie was set
		cookies := w.Result().Cookies()
		if len(cookies) != 1 {
			t.Fatalf("Expected 1 clear cookie to be set, got %d", len(cookies))
		}

		cookie := cookies[0]
		if cookie.Name != "test_auth" {
			t.Errorf("Expected cookie name 'test_auth', got %s", cookie.Name)
		}
		if cookie.MaxAge != -1 {
			t.Errorf("Expected cookie MaxAge -1, got %d", cookie.MaxAge)
		}
	})
}

func TestAuth_Clear_Integration(t *testing.T) {
	auth := createTestAuth()
	data := testData{UserID: 123, Name: "Alice"}

	handler := http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		authData, ok := auth.Get(r.Context())
		if !ok {
			t.Error("Expected to find auth data in context")
			return
		}
		if authData.UserID != 123 || authData.Name != "Alice" {
			t.Errorf("Expected UserID=123, Name=Alice, got UserID=%d, Name=%s", authData.UserID, authData.Name)
		}
		w.WriteHeader(http.StatusOK)
	})

	protectedHandler := auth.Required(handler)

	t.Run("authentication works before clear", func(t *testing.T) {
		setW := httptest.NewRecorder()
		if err := auth.Set(setW, data); err != nil {
			t.Fatalf("Set() error = %v", err)
		}
		cookie := setW.Result().Cookies()[0]

		req := httptest.NewRequest("GET", "/", nil)
		req.AddCookie(cookie)
		w := httptest.NewRecorder()

		protectedHandler.ServeHTTP(w, req)

		if w.Code != http.StatusOK {
			t.Errorf("Expected status 200, got %d", w.Code)
		}
	})

	t.Run("authentication fails after clear", func(t *testing.T) {
		setW := httptest.NewRecorder()
		if err := auth.Set(setW, data); err != nil {
			t.Fatalf("Set() error = %v", err)
		}
		originalCookie := setW.Result().Cookies()[0]

		clearW := httptest.NewRecorder()
		auth.Clear(clearW)
		clearCookie := clearW.Result().Cookies()[0]

		if clearCookie.MaxAge != -1 {
			t.Errorf("Expected clear cookie to have MaxAge -1, got %d", clearCookie.MaxAge)
		}

		req := httptest.NewRequest("GET", "/", nil)
		w := httptest.NewRecorder()

		protectedHandler.ServeHTTP(w, req)

		if w.Code != http.StatusUnauthorized {
			t.Errorf("Expected status 401 when no cookie is present (simulating browser behavior after clear), got %d", w.Code)
		}

		req2 := httptest.NewRequest("GET", "/", nil)
		req2.AddCookie(originalCookie)
		w2 := httptest.NewRecorder()

		protectedHandler.ServeHTTP(w2, req2)

		if w2.Code != http.StatusOK {
			t.Errorf("Expected original cookie to still work, got %d", w2.Code)
		}
	})
}