package middleware

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

	"github.com/gofrs/uuid/v5"
	"github.com/golang-jwt/jwt/v5"
)

// --- CORS Tests ---

func TestCORSWithConfigAllowAll(t *testing.T) {
	cfg := CORSConfig{AllowedOrigins: []string{"*"}}
	handler := CORSWithConfig(cfg)(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	req.Header.Set("Origin", "https://example.com")
	rec := httptest.NewRecorder()

	handler.ServeHTTP(rec, req)

	if rec.Header().Get("Access-Control-Allow-Origin") != "*" {
		t.Errorf("expected Access-Control-Allow-Origin '*', got '%s'", rec.Header().Get("Access-Control-Allow-Origin"))
	}
}

func TestCORSWithConfigSpecificOrigins(t *testing.T) {
	cfg := CORSConfig{AllowedOrigins: []string{"https://allowed.com", "https://another.com"}}
	handler := CORSWithConfig(cfg)(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	// Test allowed origin
	req := httptest.NewRequest(http.MethodGet, "/", nil)
	req.Header.Set("Origin", "https://allowed.com")
	rec := httptest.NewRecorder()
	handler.ServeHTTP(rec, req)

	if rec.Header().Get("Access-Control-Allow-Origin") != "https://allowed.com" {
		t.Errorf("expected origin 'https://allowed.com', got '%s'", rec.Header().Get("Access-Control-Allow-Origin"))
	}

	// Test blocked origin
	req2 := httptest.NewRequest(http.MethodGet, "/", nil)
	req2.Header.Set("Origin", "https://blocked.com")
	rec2 := httptest.NewRecorder()
	handler.ServeHTTP(rec2, req2)

	if rec2.Header().Get("Access-Control-Allow-Origin") != "" {
		t.Errorf("expected empty Access-Control-Allow-Origin, got '%s'", rec2.Header().Get("Access-Control-Allow-Origin"))
	}
}

func TestCORSPreflight(t *testing.T) {
	cfg := CORSConfig{AllowedOrigins: []string{"*"}}
	handler := CORSWithConfig(cfg)(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusTeapot) // Should not reach here
	}))

	req := httptest.NewRequest(http.MethodOptions, "/", nil)
	rec := httptest.NewRecorder()

	handler.ServeHTTP(rec, req)

	if rec.Code != http.StatusOK {
		t.Errorf("expected status 200 for preflight, got %d", rec.Code)
	}
}

func TestCORSHeaders(t *testing.T) {
	cfg := CORSConfig{AllowedOrigins: []string{"*"}}
	handler := CORSWithConfig(cfg)(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	rec := httptest.NewRecorder()

	handler.ServeHTTP(rec, req)

	if !strings.Contains(rec.Header().Get("Access-Control-Allow-Methods"), "GET") {
		t.Error("expected Access-Control-Allow-Methods to include GET")
	}
	if !strings.Contains(rec.Header().Get("Access-Control-Allow-Headers"), "Authorization") {
		t.Error("expected Access-Control-Allow-Headers to include Authorization")
	}
}

// --- Auth Tests ---

func createTestToken(secret string, userID uuid.UUID, role string, companyID *uuid.UUID) string {
	claims := jwt.MapClaims{
		"sub":  userID.String(),
		"role": role,
		"exp":  time.Now().Add(time.Hour).Unix(),
	}
	if companyID != nil {
		claims["company_id"] = companyID.String()
	}
	token := jwt.NewWithClaims(jwt.SigningMethodHS256, claims)
	tokenStr, _ := token.SignedString([]byte(secret))
	return tokenStr
}

func TestRequireAuthValidToken(t *testing.T) {
	secret := "test-secret"
	userID, _ := uuid.NewV4()
	companyID, _ := uuid.NewV4()
	tokenStr := createTestToken(secret, userID, "Admin", &companyID)

	var receivedClaims Claims
	handler := RequireAuth([]byte(secret))(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		receivedClaims, _ = GetClaims(r.Context())
		w.WriteHeader(http.StatusOK)
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	req.Header.Set("Authorization", "Bearer "+tokenStr)
	rec := httptest.NewRecorder()

	handler.ServeHTTP(rec, req)

	if rec.Code != http.StatusOK {
		t.Errorf("expected status 200, got %d", rec.Code)
	}
	if receivedClaims.UserID != userID {
		t.Errorf("expected userID %s, got %s", userID, receivedClaims.UserID)
	}
	if receivedClaims.Role != "Admin" {
		t.Errorf("expected role 'Admin', got '%s'", receivedClaims.Role)
	}
}

func TestRequireAuthMissingToken(t *testing.T) {
	handler := RequireAuth([]byte("secret"))(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	rec := httptest.NewRecorder()

	handler.ServeHTTP(rec, req)

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

func TestRequireAuthInvalidToken(t *testing.T) {
	handler := RequireAuth([]byte("secret"))(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	req.Header.Set("Authorization", "Bearer invalid-token")
	rec := httptest.NewRecorder()

	handler.ServeHTTP(rec, req)

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

func TestRequireAuthWrongSecret(t *testing.T) {
	userID, _ := uuid.NewV4()
	tokenStr := createTestToken("correct-secret", userID, "User", nil)

	handler := RequireAuth([]byte("wrong-secret"))(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	req.Header.Set("Authorization", "Bearer "+tokenStr)
	rec := httptest.NewRecorder()

	handler.ServeHTTP(rec, req)

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

func TestRequireAuthRoleRestriction(t *testing.T) {
	secret := "secret"
	userID, _ := uuid.NewV4()
	tokenStr := createTestToken(secret, userID, "User", nil)

	handler := RequireAuth([]byte(secret), "Admin")(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	req.Header.Set("Authorization", "Bearer "+tokenStr)
	rec := httptest.NewRecorder()

	handler.ServeHTTP(rec, req)

	if rec.Code != http.StatusForbidden {
		t.Errorf("expected status 403, got %d", rec.Code)
	}
}

func TestRequireAuthRoleAllowed(t *testing.T) {
	secret := "secret"
	userID, _ := uuid.NewV4()
	tokenStr := createTestToken(secret, userID, "Admin", nil)

	handler := RequireAuth([]byte(secret), "Admin")(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	req.Header.Set("Authorization", "Bearer "+tokenStr)
	rec := httptest.NewRecorder()

	handler.ServeHTTP(rec, req)

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

func TestGetClaimsFromContext(t *testing.T) {
	claims := Claims{
		UserID: uuid.Must(uuid.NewV4()),
		Role:   "Admin",
	}
	ctx := context.WithValue(context.Background(), claimsKey, claims)

	retrieved, ok := GetClaims(ctx)
	if !ok {
		t.Error("expected to retrieve claims from context")
	}
	if retrieved.UserID != claims.UserID {
		t.Errorf("expected userID %s, got %s", claims.UserID, retrieved.UserID)
	}
}

func TestGetClaimsNotInContext(t *testing.T) {
	_, ok := GetClaims(context.Background())
	if ok {
		t.Error("expected claims to not be in context")
	}
}

// --- Gzip Tests ---

func TestGzipCompression(t *testing.T) {
	handler := Gzip(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Write([]byte("Hello, World!"))
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	req.Header.Set("Accept-Encoding", "gzip")
	rec := httptest.NewRecorder()

	handler.ServeHTTP(rec, req)

	if rec.Header().Get("Content-Encoding") != "gzip" {
		t.Error("expected Content-Encoding 'gzip'")
	}

	// Decompress and verify
	reader, err := gzip.NewReader(rec.Body)
	if err != nil {
		t.Fatalf("failed to create gzip reader: %v", err)
	}
	defer reader.Close()

	body, err := io.ReadAll(reader)
	if err != nil {
		t.Fatalf("failed to read gzip body: %v", err)
	}

	if string(body) != "Hello, World!" {
		t.Errorf("expected 'Hello, World!', got '%s'", string(body))
	}
}

func TestGzipNoCompression(t *testing.T) {
	handler := Gzip(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.Write([]byte("Hello, World!"))
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	// No Accept-Encoding header
	rec := httptest.NewRecorder()

	handler.ServeHTTP(rec, req)

	if rec.Header().Get("Content-Encoding") == "gzip" {
		t.Error("should not use gzip when not requested")
	}
	if rec.Body.String() != "Hello, World!" {
		t.Errorf("expected 'Hello, World!', got '%s'", rec.Body.String())
	}
}

// --- Logger Tests ---

func TestLoggerMiddleware(t *testing.T) {
	handler := Logger(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	req := httptest.NewRequest(http.MethodGet, "/test-path", nil)
	rec := httptest.NewRecorder()

	handler.ServeHTTP(rec, req)

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

// --- CORS Legacy Wrapper Test ---

func TestCORSLegacyWrapper(t *testing.T) {
	handler := CORS(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	req.Header.Set("Origin", "https://example.com")
	rec := httptest.NewRecorder()

	handler.ServeHTTP(rec, req)

	if rec.Header().Get("Access-Control-Allow-Origin") != "*" {
		t.Errorf("expected '*', got '%s'", rec.Header().Get("Access-Control-Allow-Origin"))
	}
}

// --- Additional Auth Edge Case Tests ---

func TestRequireAuthExpiredToken(t *testing.T) {
	secret := "test-secret"
	userID, _ := uuid.NewV4()

	// Create an expired token
	token := jwt.NewWithClaims(jwt.SigningMethodHS256, jwt.MapClaims{
		"sub":  userID.String(),
		"role": "Admin",
		"exp":  time.Now().Add(-time.Hour).Unix(), // expired 1 hour ago
	})
	tokenStr, _ := token.SignedString([]byte(secret))

	handler := RequireAuth([]byte(secret))(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		t.Error("handler should not be called for expired token")
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	req.Header.Set("Authorization", "Bearer "+tokenStr)
	rec := httptest.NewRecorder()
	handler.ServeHTTP(rec, req)

	if rec.Code != http.StatusUnauthorized {
		t.Errorf("expected 401, got %d", rec.Code)
	}
}

func TestRequireAuthWrongSigningMethod(t *testing.T) {
	// Create a token with None signing method (should be rejected)
	token := jwt.NewWithClaims(jwt.SigningMethodNone, jwt.MapClaims{
		"sub":  "test-user-id",
		"role": "Admin",
		"exp":  time.Now().Add(time.Hour).Unix(),
	})
	tokenStr, _ := token.SignedString(jwt.UnsafeAllowNoneSignatureType)

	handler := RequireAuth([]byte("test-secret"))(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		t.Error("handler should not be called")
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	req.Header.Set("Authorization", "Bearer "+tokenStr)
	rec := httptest.NewRecorder()
	handler.ServeHTTP(rec, req)

	if rec.Code != http.StatusUnauthorized {
		t.Errorf("expected 401, got %d", rec.Code)
	}
}

// --- Security Headers Tests ---

func TestSecurityHeaders(t *testing.T) {
	handler := SecurityHeaders(http.HandlerFunc(func(w http.ResponseWriter, r *http.Request) {
		w.WriteHeader(http.StatusOK)
	}))

	req := httptest.NewRequest(http.MethodGet, "/", nil)
	rec := httptest.NewRecorder()
	handler.ServeHTTP(rec, req)

	if rec.Header().Get("X-Content-Type-Options") != "nosniff" {
		t.Error("expected X-Content-Type-Options: nosniff")
	}
	if rec.Header().Get("X-Frame-Options") != "DENY" {
		t.Error("expected X-Frame-Options: DENY")
	}
	if rec.Header().Get("X-XSS-Protection") != "1; mode=block" {
		t.Error("expected X-XSS-Protection: 1; mode=block")
	}
	if rec.Header().Get("Content-Security-Policy") != "default-src 'none'" {
		t.Error("expected Content-Security-Policy: default-src 'none'")
	}
	if rec.Header().Get("Cache-Control") != "no-store, max-age=0" {
		t.Error("expected Cache-Control: no-store, max-age=0")
	}
}