//go:build test
// +build test

package auth

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

	"crussell/db"
	"crussell/internal/dav"
	"crussell/testutils/fixtures"
	"crussell/testutils/jwt"
	"crussell/testutils/testdb"

	"github.com/jackc/pgx/v5/pgxpool"
)

// setupTestDB replaces the global db.DB with a test pool and returns a cleanup function
func setupTestDB(t *testing.T) func() {
	t.Helper()

	pool := testdb.Pool(t)
	testdb.Migrate(t, pool)

	// Replace global db.DB with test pool
	originalDB := db.DB
	db.DB = pool

	// Initialize JWT for tests
	jwt.Init()

	// Set up a minimal dav.Service to avoid nil pointer panic
	// The real service is only used in a goroutine in RegisterHandler
	dav.Service = &dav.BaseService{}

	return func() {
		db.DB = originalDB
		pool.Close()
	}
}

// helper function to make JSON request
func makeRequest(handler http.Handler, method, path string, body interface{}) *httptest.ResponseRecorder {
	var req *http.Request
	if body != nil {
		bodyBytes, _ := json.Marshal(body)
		req = httptest.NewRequest(method, path, bytes.NewReader(bodyBytes))
		req.Header.Set("Content-Type", "application/json")
	} else {
		req = httptest.NewRequest(method, path, nil)
	}
	w := httptest.NewRecorder()
	handler.ServeHTTP(w, req)
	return w
}

// Helper to parse response body
func parseResponseBody(w *httptest.ResponseRecorder, dest interface{}) error {
	return json.Unmarshal(w.Body.Bytes(), dest)
}

// =============================================================================
// Register Handler Tests
// =============================================================================

func TestRegister_Success(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(RegisterHandler)

	body := RegisterRequest{
		FirstName:      "John",
		LastName:       "Doe",
		Email:          "john.doe@test.com",
		Password:       "password123",
		Phone:          "07700900000",
		DateOfBirth:    "1990-01-15",
		AgreedToPolicy: true,
	}

	w := makeRequest(handler, "POST", "/api/register", body)

	if w.Code != http.StatusCreated {
		t.Errorf("expected status 201, got %d. body: %s", w.Code, w.Body.String())
	}

	// Verify user was created in DB
	var userID string
	err := db.DB.QueryRow(context.Background(),
		"SELECT id FROM users WHERE email = $1", "john.doe@test.com").Scan(&userID)
	if err != nil {
		t.Errorf("failed to find user in DB: %v", err)
	}

	// Clean up
	db.DB.Exec(context.Background(), "DELETE FROM users WHERE id = $1", userID)
}

func TestRegister_InvalidInput_MissingFields(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(RegisterHandler)

	tests := []struct {
		name string
		body RegisterRequest
	}{
		{
			name: "missing firstName",
			body: RegisterRequest{LastName: "Doe", Email: "test@test.com", Password: "pass", Phone: "07700900000", DateOfBirth: "1990-01-15", AgreedToPolicy: true},
		},
		{
			name: "missing lastName",
			body: RegisterRequest{FirstName: "John", Email: "test@test.com", Password: "pass", Phone: "07700900000", DateOfBirth: "1990-01-15", AgreedToPolicy: true},
		},
		{
			name: "missing email",
			body: RegisterRequest{FirstName: "John", LastName: "Doe", Password: "pass", Phone: "07700900000", DateOfBirth: "1990-01-15", AgreedToPolicy: true},
		},
		{
			name: "missing phone",
			body: RegisterRequest{FirstName: "John", LastName: "Doe", Email: "test@test.com", Password: "pass", DateOfBirth: "1990-01-15", AgreedToPolicy: true},
		},
		{
			name: "missing dateOfBirth",
			body: RegisterRequest{FirstName: "John", LastName: "Doe", Email: "test@test.com", Password: "pass", Phone: "07700900000", AgreedToPolicy: true},
		},
		{
			name: "did not agree to policy",
			body: RegisterRequest{FirstName: "John", LastName: "Doe", Email: "test@test.com", Password: "pass", Phone: "07700900000", DateOfBirth: "1990-01-15", AgreedToPolicy: false},
		},
	}

	for _, tt := range tests {
		t.Run(tt.name, func(t *testing.T) {
			w := makeRequest(handler, "POST", "/api/register", tt.body)
			if w.Code != http.StatusBadRequest {
				t.Errorf("expected status 400, got %d", w.Code)
			}
		})
	}
}

func TestRegister_InvalidInput_InvalidEmail(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(RegisterHandler)

	body := RegisterRequest{
		FirstName:      "John",
		LastName:       "Doe",
		Email:          "not-an-email",
		Password:       "password123",
		Phone:          "07700900000",
		DateOfBirth:    "1990-01-15",
		AgreedToPolicy: true,
	}

	w := makeRequest(handler, "POST", "/api/register", body)

	if w.Code != http.StatusBadRequest {
		t.Errorf("expected status 400, got %d. body: %s", w.Code, w.Body.String())
	}
}

func TestRegister_InvalidInput_InvalidPhone(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(RegisterHandler)

	body := RegisterRequest{
		FirstName:      "John",
		LastName:       "Doe",
		Email:          "john@test.com",
		Password:       "password123",
		Phone:          "12345", // Not a valid UK phone
		DateOfBirth:    "1990-01-15",
		AgreedToPolicy: true,
	}

	w := makeRequest(handler, "POST", "/api/register", body)

	if w.Code != http.StatusBadRequest {
		t.Errorf("expected status 400, got %d. body: %s", w.Code, w.Body.String())
	}
}

func TestRegister_InvalidInput_Under16(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(RegisterHandler)

	// Calculate a date that makes them under 16
	under16DOB := time.Now().AddDate(-15, 0, 0).Format("2006-01-02")

	body := RegisterRequest{
		FirstName:      "Young",
		LastName:       "User",
		Email:          "young@test.com",
		Password:       "password123",
		Phone:          "07700900000",
		DateOfBirth:    under16DOB,
		AgreedToPolicy: true,
	}

	w := makeRequest(handler, "POST", "/api/register", body)

	if w.Code != http.StatusBadRequest {
		t.Errorf("expected status 400, got %d. body: %s", w.Code, w.Body.String())
	}
}

func TestRegister_DuplicateEmail(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(RegisterHandler)

	// First create a user
	userID, err := fixtures.CreateTestUser(db.DB)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}
	defer fixtures.DeleteUser(db.DB, userID)

	// Now try to register with same email
	body := RegisterRequest{
		FirstName:      "John",
		LastName:       "Doe",
		Email:          "user@test.com", // Same as fixture
		Password:       "password123",
		Phone:          "07700900000",
		DateOfBirth:    "1990-01-15",
		AgreedToPolicy: true,
	}

	w := makeRequest(handler, "POST", "/api/register", body)

	if w.Code != http.StatusConflict {
		t.Errorf("expected status 409, got %d. body: %s", w.Code, w.Body.String())
	}
}

// =============================================================================
// Login Handler Tests
// =============================================================================

func TestLogin_Success(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(LoginHandler)

	// Create a test user
	userID, err := fixtures.CreateTestUser(db.DB)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}
	defer fixtures.DeleteUser(db.DB, userID)

	body := LoginRequest{
		Email:    "user@test.com",
		Password: "testpassword123",
	}

	w := makeRequest(handler, "POST", "/api/login", body)

	if w.Code != http.StatusOK {
		t.Errorf("expected status 200, got %d. body: %s", w.Code, w.Body.String())
	}

	var resp struct {
		Token string `json:"token"`
	}
	if err := parseResponseBody(w, &resp); err != nil {
		t.Errorf("failed to parse response: %v", err)
	}

	if resp.Token == "" {
		t.Error("expected token in response, got empty string")
	}
}

func TestLogin_InvalidCredentials_WrongPassword(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(LoginHandler)

	// Create a test user
	userID, err := fixtures.CreateTestUser(db.DB)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}
	defer fixtures.DeleteUser(db.DB, userID)

	body := LoginRequest{
		Email:    "user@test.com",
		Password: "wrongpassword",
	}

	w := makeRequest(handler, "POST", "/api/login", body)

	if w.Code != http.StatusUnauthorized {
		t.Errorf("expected status 401, got %d. body: %s", w.Code, w.Body.String())
	}
}

func TestLogin_InvalidCredentials_NonExistentEmail(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(LoginHandler)

	body := LoginRequest{
		Email:    "nonexistent@test.com",
		Password: "password123",
	}

	w := makeRequest(handler, "POST", "/api/login", body)

	if w.Code != http.StatusUnauthorized {
		t.Errorf("expected status 401, got %d. body: %s", w.Code, w.Body.String())
	}
}

// =============================================================================
// Refresh Token Handler Tests
// =============================================================================

func TestRefreshToken_Success(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(RefreshTokenHandler)

	// Create a test user
	userID, err := fixtures.CreateTestUser(db.DB)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}
	defer fixtures.DeleteUser(db.DB, userID)

	// Generate a valid token
	token := jwt.GenerateTestToken(userID, "verified_email")

	req := httptest.NewRequest("POST", "/api/refresh-token", nil)
	req.Header.Set("Authorization", "Bearer "+token)
	w := httptest.NewRecorder()

	// Use the middleware to set up context
	ctx := req.Context()
	ctx = context.WithValue(ctx, "user_id", userID)
	ctx = context.WithValue(ctx, "user_role", "verified_email")
	req = req.WithContext(ctx)

	handler.ServeHTTP(w, req)

	if w.Code != http.StatusOK {
		t.Errorf("expected status 200, got %d. body: %s", w.Code, w.Body.String())
	}

	var resp struct {
		Token string `json:"token"`
	}
	if err := parseResponseBody(w, &resp); err != nil {
		t.Errorf("failed to parse response: %v", err)
	}

	if resp.Token == "" {
		t.Error("expected new token in response, got empty string")
	}
}

func TestRefreshToken_Unauthorized_NoToken(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(RefreshTokenHandler)

	req := httptest.NewRequest("POST", "/api/refresh-token", nil)
	w := httptest.NewRecorder()

	handler.ServeHTTP(w, req)

	// Without proper auth middleware, userID/role won't be in context
	// The handler tries to query DB with empty userID, which should fail
	if w.Code != http.StatusUnauthorized && w.Code != http.StatusInternalServerError {
		t.Errorf("expected status 401 or 500, got %d. body: %s", w.Code, w.Body.String())
	}
}

// =============================================================================
// Verify Generate Handler Tests
// =============================================================================

func TestVerifyGenerate_ValidEmail(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(GenerateVerificationCodeHandler)

	// Create a test user
	userID, err := fixtures.CreateTestUser(db.DB)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}
	defer fixtures.DeleteUser(db.DB, userID)

	body := VerificationCodeRequest{
		Email: "user@test.com",
	}

	w := makeRequest(handler, "POST", "/api/verify/generate", body)

	if w.Code != http.StatusOK {
		t.Errorf("expected status 200, got %d. body: %s", w.Code, w.Body.String())
	}

	var resp VerificationResponse
	if err := parseResponseBody(w, &resp); err != nil {
		t.Errorf("failed to parse response: %v", err)
	}

	if !resp.Success {
		t.Error("expected success=true in response")
	}

	// Verify a code was created in DB
	var codeID string
	err = db.DB.QueryRow(context.Background(),
		"SELECT id FROM verification_codes WHERE user_id = $1", userID).Scan(&codeID)
	if err != nil {
		t.Errorf("failed to find verification code in DB: %v", err)
	}

	// Clean up
	db.DB.Exec(context.Background(), "DELETE FROM verification_codes WHERE user_id = $1", userID)
}

func TestVerifyGenerate_NonExistentEmail(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(GenerateVerificationCodeHandler)

	// Security: should return success even if email doesn't exist
	body := VerificationCodeRequest{
		Email: "nonexistent@test.com",
	}

	w := makeRequest(handler, "POST", "/api/verify/generate", body)

	if w.Code != http.StatusOK {
		t.Errorf("expected status 200, got %d. body: %s", w.Code, w.Body.String())
	}

	var resp VerificationResponse
	if err := parseResponseBody(w, &resp); err != nil {
		t.Errorf("failed to parse response: %v", err)
	}

	// Should return success for security (don't reveal if email exists)
	if !resp.Success {
		t.Error("expected success=true in response for non-existent email")
	}
}

// =============================================================================
// Verify Check Handler Tests
// =============================================================================

func TestVerifyCheck_ValidCode(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(VerifyCodeHandler)

	// Create a test user
	userID, err := fixtures.CreateTestUser(db.DB)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}
	defer fixtures.DeleteUser(db.DB, userID)

	// Create a verification code
	var code string
	expiresAt := time.Now().Add(24 * time.Hour)
	err = db.DB.QueryRow(context.Background(),
		`INSERT INTO verification_codes (user_id, purpose, expires_at) VALUES ($1, 'email_verify', $2) RETURNING code`,
		userID, expiresAt).Scan(&code)
	if err != nil {
		t.Fatalf("failed to create verification code: %v", err)
	}
	defer db.DB.Exec(context.Background(), "DELETE FROM verification_codes WHERE user_id = $1", userID)

	body := VerifyCodeRequest{
		Code: code,
	}

	w := makeRequest(handler, "POST", "/api/verify/check", body)

	if w.Code != http.StatusOK {
		t.Errorf("expected status 200, got %d. body: %s", w.Code, w.Body.String())
	}

	var resp VerificationResponse
	if err := parseResponseBody(w, &resp); err != nil {
		t.Errorf("failed to parse response: %v", err)
	}

	if !resp.Success {
		t.Error("expected success=true in response")
	}

	// Verify code is marked as used
	var usedAt *time.Time
	err = db.DB.QueryRow(context.Background(),
		"SELECT used_at FROM verification_codes WHERE code = $1", code).Scan(&usedAt)
	if err != nil || usedAt == nil {
		t.Error("expected verification code to be marked as used")
	}
}

func TestVerifyCheck_InvalidCode(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(VerifyCodeHandler)

	body := VerifyCodeRequest{
		Code: "nonexistent-code-12345",
	}

	w := makeRequest(handler, "POST", "/api/verify/check", body)

	if w.Code != http.StatusBadRequest {
		t.Errorf("expected status 400, got %d. body: %s", w.Code, w.Body.String())
	}
}

func TestVerifyCheck_ExpiredCode(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(VerifyCodeHandler)

	// Create a test user
	userID, err := fixtures.CreateTestUser(db.DB)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}
	defer fixtures.DeleteUser(db.DB, userID)

	// Create an expired verification code
	var code string
	expiresAt := time.Now().Add(-1 * time.Hour) // Expired 1 hour ago
	err = db.DB.QueryRow(context.Background(),
		`INSERT INTO verification_codes (user_id, purpose, expires_at) VALUES ($1, 'email_verify', $2) RETURNING code`,
		userID, expiresAt).Scan(&code)
	if err != nil {
		t.Fatalf("failed to create verification code: %v", err)
	}
	defer db.DB.Exec(context.Background(), "DELETE FROM verification_codes WHERE user_id = $1", userID)

	body := VerifyCodeRequest{
		Code: code,
	}

	w := makeRequest(handler, "POST", "/api/verify/check", body)

	if w.Code != http.StatusBadRequest {
		t.Errorf("expected status 400, got %d. body: %s", w.Code, w.Body.String())
	}
}

// =============================================================================
// Additional Edge Case Tests
// =============================================================================

func TestLogin_InvalidRequest(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(LoginHandler)

	// Send invalid JSON
	req := httptest.NewRequest("POST", "/api/login", bytes.NewReader([]byte("not json")))
	req.Header.Set("Content-Type", "application/json")
	w := httptest.NewRecorder()
	handler.ServeHTTP(w, req)

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

func TestRegister_NameTooLong(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(RegisterHandler)

	// First name > 50 chars
	longName := string(bytes.Repeat([]byte("a"), 51))
	body := RegisterRequest{
		FirstName:      longName,
		LastName:       "Doe",
		Email:          "john@test.com",
		Password:       "password123",
		Phone:          "07700900000",
		DateOfBirth:    "1990-01-15",
		AgreedToPolicy: true,
	}

	w := makeRequest(handler, "POST", "/api/register", body)

	if w.Code != http.StatusBadRequest {
		t.Errorf("expected status 400, got %d. body: %s", w.Code, w.Body.String())
	}
}

func TestRegister_InvalidNameCharacters(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(RegisterHandler)

	// Name with numbers (invalid)
	body := RegisterRequest{
		FirstName:      "John123",
		LastName:       "Doe",
		Email:          "john@test.com",
		Password:       "password123",
		Phone:          "07700900000",
		DateOfBirth:    "1990-01-15",
		AgreedToPolicy: true,
	}

	w := makeRequest(handler, "POST", "/api/register", body)

	if w.Code != http.StatusBadRequest {
		t.Errorf("expected status 400, got %d. body: %s", w.Code, w.Body.String())
	}
}

func TestVerifyCheck_AlreadyUsed(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(VerifyCodeHandler)

	// Create a test user
	userID, err := fixtures.CreateTestUser(db.DB)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}
	defer fixtures.DeleteUser(db.DB, userID)

	// Create a verification code
	var code string
	expiresAt := time.Now().Add(24 * time.Hour)
	err = db.DB.QueryRow(context.Background(),
		`INSERT INTO verification_codes (user_id, purpose, expires_at) VALUES ($1, 'email_verify', $2) RETURNING code`,
		userID, expiresAt).Scan(&code)
	if err != nil {
		t.Fatalf("failed to create verification code: %v", err)
	}
	defer db.DB.Exec(context.Background(), "DELETE FROM verification_codes WHERE user_id = $1", userID)

	// First verification should succeed
	body := VerifyCodeRequest{
		Code: code,
	}
	w := makeRequest(handler, "POST", "/api/verify/check", body)
	if w.Code != http.StatusOK {
		t.Errorf("first verification: expected status 200, got %d", w.Code)
	}

	// Second verification with same code should return 403 (already used)
	w = makeRequest(handler, "POST", "/api/verify/check", body)
	if w.Code != http.StatusForbidden {
		t.Errorf("second verification: expected status 403, got %d", w.Code)
	}
}

func TestVerifyCheck_RoleChangeToVerified(t *testing.T) {
	cleanup := setupTestDB(t)
	defer cleanup()

	handler := http.HandlerFunc(VerifyCodeHandler)

	// Create an unverified user
	userID, err := fixtures.CreateTestUnverifiedUser(db.DB)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}
	defer fixtures.DeleteUser(db.DB, userID)

	// Verify initial role is unverified_email
	var initialRole string
	err = db.DB.QueryRow(context.Background(),
		"SELECT account_role FROM users WHERE id = $1", userID).Scan(&initialRole)
	if err != nil {
		t.Fatalf("failed to check initial role: %v", err)
	}
	if initialRole != "unverified_email" {
		t.Errorf("expected initial role 'unverified_email', got %s", initialRole)
	}

	// Create a verification code
	var code string
	expiresAt := time.Now().Add(24 * time.Hour)
	err = db.DB.QueryRow(context.Background(),
		`INSERT INTO verification_codes (user_id, purpose, expires_at) VALUES ($1, 'email_verify', $2) RETURNING code`,
		userID, expiresAt).Scan(&code)
	if err != nil {
		t.Fatalf("failed to create verification code: %v", err)
	}
	defer db.DB.Exec(context.Background(), "DELETE FROM verification_codes WHERE user_id = $1", userID)

	// Verify the code
	body := VerifyCodeRequest{
		Code: code,
	}
	w := makeRequest(handler, "POST", "/api/verify/check", body)
	if w.Code != http.StatusOK {
		t.Errorf("expected status 200, got %d. body: %s", w.Code, w.Body.String())
	}

	// Check that user's role changed to verified_email
	var newRole string
	err = db.DB.QueryRow(context.Background(),
		"SELECT account_role FROM users WHERE id = $1", userID).Scan(&newRole)
	if err != nil {
		t.Errorf("failed to check new role: %v", err)
	}
	if newRole != "verified_email" {
		t.Errorf("expected role to change to 'verified_email', got %s", newRole)
	}
}
// Ensure test compilation - import pgxpool to avoid unused import
var _ = func() *pgxpool.Pool { return nil }