//go:build test && dev

package user

// Package user contains coverage-improving tests for user profile,
// account management, guest creation, and admin handlers.
//
// These tests focus on error paths and edge cases not covered by the
// existing test suite, such as unauthorized access, not-found scenarios,
// invalid JSON bodies, and duplicate email conflicts.
//
// NOTE: Do NOT use t.Parallel() in this file.

import (
	"bytes"
	"context"
	"database/sql"
	"encoding/json"
	"fmt"
	"log"
	"net/http"
	"net/http/httptest"
	"os"
	"strings"
	"sync"
	"testing"
	"time"

	"github.com/go-chi/chi/v5"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"

	"crussell/db"
	"crussell/handlers/payments"
	"crussell/internal/square"
	"crussell/mw"
	"crussell/testutils"
	"crussell/testutils/fixtures"
)

// =============================================================================
// DeleteAccountHandler Coverage Tests
// =============================================================================

// TestDeleteAccount_Unauthorized verifies that deleting an account without
// setting user ID in context returns 401 Unauthorized.
func TestDeleteAccount_Unauthorized(t *testing.T) {
	req := httptest.NewRequest(http.MethodDelete, "/api/user/account", nil)
	rr := httptest.NewRecorder()
	DeleteAccountHandler(rr, req)

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

// TestDeleteAccount_NotFound verifies that deleting a non-existent user
// (valid userID format in context but no matching DB row) returns 404.
func TestDeleteAccount_NotFound(t *testing.T) {
	ctx, _ := testutils.SetupTestTx(t)

	req := httptest.NewRequest(http.MethodDelete, "/api/user/account", nil)
	req = req.WithContext(context.WithValue(ctx, mw.UserIDKey, "nonexistent123"))
	rr := httptest.NewRecorder()
	DeleteAccountHandler(rr, req)

	if rr.Code != http.StatusNotFound {
		t.Errorf("expected 404, got %d. body: %s", rr.Code, rr.Body.String())
	}
}

// TestDeleteAccount_WithBooking verifies that deleting a registered user
// account with existing bookings succeeds (anonymize_user handles FK).
func TestDeleteAccount_WithBooking(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	userID, err := fixtures.CreateTestUser(tx)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}

	serviceID, err := fixtures.CreateTestService(tx)
	if err != nil {
		t.Fatalf("failed to create service: %v", err)
	}

	_, err = fixtures.CreateTestBooking(tx, userID, serviceID)
	if err != nil {
		t.Fatalf("failed to create booking: %v", err)
	}

	req := httptest.NewRequest(http.MethodDelete, "/api/user/account", nil)
	req = req.WithContext(context.WithValue(ctx, mw.UserIDKey, userID))
	rr := httptest.NewRecorder()
	DeleteAccountHandler(rr, req)

	if rr.Code != http.StatusNoContent {
		t.Errorf("expected 204, got %d. body: %s", rr.Code, rr.Body.String())
	}

	// Verify user was anonymized
	var firstName, accountRole string
	err = tx.QueryRow(ctx, `SELECT n_first_name, account_role FROM users WHERE id = $1`, userID).Scan(&firstName, &accountRole)
	if err != nil {
		t.Fatalf("failed to query anonymized user: %v", err)
	}
	if firstName != "Deleted" {
		t.Errorf("expected first name 'Deleted', got %q", firstName)
	}
	if accountRole != "guest" {
		t.Errorf("expected account_role 'guest', got %q", accountRole)
	}
}

// TestDeleteAccount_GuestWithBooking verifies that deleting a guest user
// with existing bookings succeeds (delete_guest_user handles FK).
func TestDeleteAccount_GuestWithBooking(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	userID, err := fixtures.CreateTestGuestUser(tx)
	if err != nil {
		t.Fatalf("failed to create guest user: %v", err)
	}

	serviceID, err := fixtures.CreateTestService(tx)
	if err != nil {
		t.Fatalf("failed to create service: %v", err)
	}

	_, err = fixtures.CreateTestBooking(tx, userID, serviceID)
	if err != nil {
		t.Fatalf("failed to create booking: %v", err)
	}

	req := httptest.NewRequest(http.MethodDelete, "/api/user/account", nil)
	req = req.WithContext(context.WithValue(ctx, mw.UserIDKey, userID))
	rr := httptest.NewRecorder()
	DeleteAccountHandler(rr, req)

	if rr.Code != http.StatusNoContent {
		t.Errorf("expected 204, got %d. body: %s", rr.Code, rr.Body.String())
	}

	// Verify guest user was fully deleted
	var count int
	err = tx.QueryRow(ctx, `SELECT COUNT(*) FROM users WHERE id = $1`, userID).Scan(&count)
	if err != nil {
		t.Fatalf("failed to query user count: %v", err)
	}
	if count != 0 {
		t.Errorf("expected user to be deleted, found %d rows", count)
	}
}

// =============================================================================
// ChangePasswordHandler Coverage Tests
// =============================================================================

// TestPasswordChange_Unauthorized verifies that changing password without
// user ID in context returns 401.
func TestPasswordChange_Unauthorized(t *testing.T) {
	changeReq := ChangePasswordRequest{
		CurrentPassword: "testpassword123",
		NewPassword:     "newpassword456",
	}
	body, _ := json.Marshal(changeReq)

	req := httptest.NewRequest(http.MethodPut, "/api/user/change-password", bytes.NewReader(body))
	req.Header.Set("Content-Type", "application/json")
	rr := httptest.NewRecorder()
	ChangePasswordHandler(rr, req)

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

// TestPasswordChange_InvalidJSON verifies that sending an invalid JSON body
// returns 400 Bad Request.
func TestPasswordChange_InvalidJSON(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	userID, err := fixtures.CreateTestUser(tx)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}

	req := httptest.NewRequest(http.MethodPut, "/api/user/change-password", bytes.NewReader([]byte("not valid json")))
	req.Header.Set("Content-Type", "application/json")
	req = req.WithContext(context.WithValue(ctx, mw.UserIDKey, userID))
	rr := httptest.NewRecorder()
	ChangePasswordHandler(rr, req)

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

// TestPasswordChange_UserNotFound verifies that changing password for a
// non-existent user ID returns 404.
func TestPasswordChange_UserNotFound(t *testing.T) {
	ctx, _ := testutils.SetupTestTx(t)

	changeReq := ChangePasswordRequest{
		CurrentPassword: "testpassword123",
		NewPassword:     "newpassword456",
	}
	body, _ := json.Marshal(changeReq)

	req := httptest.NewRequest(http.MethodPut, "/api/user/change-password", bytes.NewReader(body))
	req.Header.Set("Content-Type", "application/json")
	req = req.WithContext(context.WithValue(ctx, mw.UserIDKey, "nonexistent123"))
	rr := httptest.NewRecorder()
	ChangePasswordHandler(rr, req)

	if rr.Code != http.StatusNotFound {
		t.Errorf("expected 404, got %d. body: %s", rr.Code, rr.Body.String())
	}
}

// =============================================================================
// Notification Preferences Coverage Tests
// =============================================================================

// TestNotificationPreferences_Get_Unauthorized verifies that getting
// notification preferences without auth returns 401.
func TestNotificationPreferences_Get_Unauthorized(t *testing.T) {
	req := httptest.NewRequest(http.MethodGet, "/api/user/notification-preferences", nil)
	rr := httptest.NewRecorder()
	GetNotificationPreferencesHandler(rr, req)

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

// TestNotificationPreferences_Update_Unauthorized verifies that updating
// notification preferences without auth returns 401.
func TestNotificationPreferences_Update_Unauthorized(t *testing.T) {
	body, _ := json.Marshal(UpdateNotificationPreferencesRequest{})

	req := httptest.NewRequest(http.MethodPut, "/api/user/notification-preferences", bytes.NewReader(body))
	req.Header.Set("Content-Type", "application/json")
	rr := httptest.NewRecorder()
	UpdateNotificationPreferencesHandler(rr, req)

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

// TestNotificationPreferences_Update_InvalidJSON verifies that sending
// invalid JSON to update notification preferences returns 400.
func TestNotificationPreferences_Update_InvalidJSON(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	userID, err := fixtures.CreateTestUser(tx)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}

	req := httptest.NewRequest(http.MethodPut, "/api/user/notification-preferences", bytes.NewReader([]byte("{")))
	req.Header.Set("Content-Type", "application/json")
	req = req.WithContext(context.WithValue(ctx, mw.UserIDKey, userID))
	rr := httptest.NewRecorder()
	UpdateNotificationPreferencesHandler(rr, req)

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

// =============================================================================
// UpdateProfileHandler Coverage Tests
// =============================================================================

// TestProfile_Update_InvalidJSON verifies that sending an invalid JSON body
// to update profile returns 400.
func TestProfile_Update_InvalidJSON(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	userID, err := fixtures.CreateTestUser(tx)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}

	req := httptest.NewRequest(http.MethodPut, "/api/user/profile", bytes.NewReader([]byte("not json")))
	req.Header.Set("Content-Type", "application/json")
	req = req.WithContext(context.WithValue(ctx, mw.UserIDKey, userID))
	rr := httptest.NewRecorder()
	UpdateProfileHandler(rr, req)

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

// =============================================================================
// Guest User Coverage Tests
// =============================================================================

// TestGuestUser_Create_DuplicateEmail verifies that creating a guest user
// with an email already registered by a non-guest user returns 409 Conflict.
func TestGuestUser_Create_DuplicateEmail(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	// Create a registered (non-guest) user with a known email
	_, err := fixtures.CreateTestUserWithEmail(tx, "registered.dup@example.com", "verified_email")
	if err != nil {
		t.Fatalf("failed to create registered user: %v", err)
	}

	// Try to create a guest with the same email
	reqBody := CreateGuestUserRequest{
		FirstName: "Guest",
		LastName:  "User",
		Email:     "registered.dup@example.com",
		Phone:     "07123456789",
	}
	body, _ := json.Marshal(reqBody)

	req := httptest.NewRequest(http.MethodPost, "/api/user/guest", bytes.NewReader(body))
	req.Header.Set("Content-Type", "application/json")
	req = req.WithContext(ctx)
	rr := httptest.NewRecorder()
	CreateGuestUserHandler(rr, req)

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

// TestGuestUser_Create_InvalidJSON verifies that sending invalid JSON
// returns 400 Bad Request.
func TestGuestUser_Create_InvalidJSON(t *testing.T) {
	req := httptest.NewRequest(http.MethodPost, "/api/user/guest", bytes.NewReader([]byte("{")))
	req.Header.Set("Content-Type", "application/json")
	rr := httptest.NewRecorder()
	CreateGuestUserHandler(rr, req)

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

// TestGuestUser_Create_InvalidNameCharacters verifies that invalid characters
// in name (e.g., numbers in first name) return 400.
func TestGuestUser_Create_InvalidNameCharacters(t *testing.T) {
	reqBody := CreateGuestUserRequest{
		FirstName: "John123",
		LastName:  "Doe",
		Email:     "john.doe@example.com",
		Phone:     "07123456789",
	}
	body, _ := json.Marshal(reqBody)

	req := httptest.NewRequest(http.MethodPost, "/api/user/guest", bytes.NewReader(body))
	req.Header.Set("Content-Type", "application/json")
	rr := httptest.NewRecorder()
	CreateGuestUserHandler(rr, req)

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

// =============================================================================
// Admin Handler Coverage Tests
// =============================================================================

// TestGetEligiblePatchTestServices_InvalidUserID verifies that an invalid
// user ID format returns 404.
func TestGetEligiblePatchTestServices_InvalidUserID(t *testing.T) {
	ctx, _ := testutils.SetupTestTx(t)

	handler := http.HandlerFunc(GetEligiblePatchTestServicesHandler)
	w := makeAdminHandlerRequest(handler, "GET", "/api/admin/users/invalid/patch-tests/eligible", nil, ctx)

	if w.Code != http.StatusNotFound {
		t.Errorf("expected 404, got %d. body: %s", w.Code, w.Body.String())
	}
}

// TestGetUserPatchTests_NoMatchUser verifies that requesting patch tests for
// a valid-format but non-existent user returns an empty list (200 OK).
func TestGetUserPatchTests_NoMatchUser(t *testing.T) {
	ctx, _ := testutils.SetupTestTx(t)

	// Use a valid 12-char hex ID that doesn't exist in the DB
	w := makePatchTestsRequest(GetUserPatchTestsHandler, "GET", "/api/admin/users/aaaa00000000/patch-tests", nil, "admin001", "admin", ctx)
	if w.Code != http.StatusOK {
		t.Errorf("expected 200, got %d. body: %s", w.Code, w.Body.String())
		return
	}

	var tests []UserPatchTest
	if err := json.Unmarshal(w.Body.Bytes(), &tests); err != nil {
		t.Fatalf("failed to unmarshal response: %v", err)
	}
}

// TestGetEligiblePatchTestServices_NoMatchUser verifies that eligible patch
// tests for a valid-format but non-existent user returns an empty list.
func TestGetEligiblePatchTestServices_NoMatchUser(t *testing.T) {
	ctx, _ := testutils.SetupTestTx(t)

	handler := http.HandlerFunc(GetEligiblePatchTestServicesHandler)
	w := makeAdminHandlerRequest(handler, "GET", "/api/admin/users/bbbb00000000/patch-tests/eligible", nil, ctx)

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

	var services []ServiceForPatchTest
	if err := json.Unmarshal(w.Body.Bytes(), &services); err != nil {
		t.Fatalf("failed to unmarshal response: %v", err)
	}
}

// TestAddPatchTest_InvalidUserID verifies that adding a patch test with an
// invalid user ID returns 404.
func TestAddPatchTest_InvalidUserID(t *testing.T) {
	ctx, _ := testutils.SetupTestTx(t)

	handler := http.HandlerFunc(AddPatchTestHandler)
	reqBody := AddPatchTestRequest{PatchTestID: "testid1234567"}
	w := makeAdminHandlerRequest(handler, "POST", "/api/admin/users/invalid/patch-tests", reqBody, ctx)

	if w.Code != http.StatusNotFound {
		t.Errorf("expected 404, got %d. body: %s", w.Code, w.Body.String())
	}
}

// TestAddPatchTest_EmptyPatchTestID verifies that adding a patch test with
// an empty patch_test_id returns 400.
func TestAddPatchTest_EmptyPatchTestID(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	userID, err := fixtures.CreateTestUser(tx)
	if err != nil {
		t.Fatalf("failed to create user: %v", err)
	}

	handler := http.HandlerFunc(AddPatchTestHandler)
	reqBody := AddPatchTestRequest{PatchTestID: ""}
	w := makeAdminHandlerRequest(handler, "POST", "/api/admin/users/"+userID+"/patch-tests", reqBody, ctx)

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

func TestAddPatchTest_InvalidJSON(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	userID, err := fixtures.CreateTestUser(tx)
	if err != nil {
		t.Fatalf("failed to create user: %v", err)
	}

	handler := http.HandlerFunc(AddPatchTestHandler)
	rctx := chi.NewRouteContext()
	rctx.URLParams.Add("id", userID)
	chiCtx := context.WithValue(ctx, chi.RouteCtxKey, rctx)
	chiCtx = context.WithValue(chiCtx, mw.UserIDKey, "admin-test-id")
	chiCtx = context.WithValue(chiCtx, mw.UserRoleKey, "admin")

	req := httptest.NewRequest(http.MethodPost, "/api/admin/users/"+userID+"/patch-tests", bytes.NewReader([]byte("not json")))
	req.Header.Set("Content-Type", "application/json")
	req = req.WithContext(chiCtx)

	rr := httptest.NewRecorder()
	handler.ServeHTTP(rr, req)

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

// TestListAdminUsers_Search verifies that the list admin users handler
// works with a search query parameter.
func TestListAdminUsers_Search(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	// Create a user with a distinct name
	_, err := tx.Exec(ctx, `
		INSERT INTO users (n_first_name, n_last_name, email, phone, date_of_birth, password_hash, account_role, account_type)
		VALUES ('Searchable', 'User', 'searchable@test.com', '+447123456789', '1990-01-01', 'hash', 'verified_email', 'email')
	`)
	if err != nil {
		t.Fatalf("failed to create searchable user: %v", err)
	}

	handler := http.HandlerFunc(ListAdminUsersHandler)
	w := makeAdminHandlerRequest(handler, "GET", "/api/admin/users?q=Searchable", nil, ctx)

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

	var response UserListResponse
	if err := json.Unmarshal(w.Body.Bytes(), &response); err != nil {
		t.Fatalf("failed to unmarshal response: %v", err)
	}

	if response.Total < 1 {
		t.Errorf("expected at least 1 user in search results, got %d", response.Total)
	}
}

// TestListAdminUsers_SearchWithCursor verifies that the list admin users
// handler works with search + cursor pagination.
func TestListAdminUsers_SearchWithCursor(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	// Create some users so cursor pagination has data
	for i := 0; i < 3; i++ {
		_, err := tx.Exec(ctx, `
			INSERT INTO users (n_first_name, n_last_name, email, phone, date_of_birth, password_hash, account_role, account_type)
			VALUES ('Cursor', $1, $2, '+447123456789', '1990-01-01', 'hash', 'verified_email', 'email')
		`, "TestUser_"+string(rune('A'+i)), "cursor.user."+string(rune('A'+i))+"@test.com")
		if err != nil {
			t.Fatalf("failed to create cursor test user: %v", err)
		}
	}

	// First request without cursor
	handler := http.HandlerFunc(ListAdminUsersHandler)
	w := makeAdminHandlerRequest(handler, "GET", "/api/admin/users?q=Cursor&per_page=2", nil, ctx)

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

	var firstPage UserListResponse
	if err := json.Unmarshal(w.Body.Bytes(), &firstPage); err != nil {
		t.Fatalf("failed to unmarshal first page: %v", err)
	}

	// If we have a next cursor, use it
	if firstPage.NextCursor != nil {
		w2 := makeAdminHandlerRequest(handler, "GET", "/api/admin/users?q=Cursor&per_page=2&cursor="+*firstPage.NextCursor, nil, ctx)
		if w2.Code != http.StatusOK {
			t.Errorf("expected 200 for cursor page, got %d. body: %s", w2.Code, w2.Body.String())
		}
	}
}

// =============================================================================
// DeleteAccountHandler — S3 goroutine coverage
// =============================================================================

// TestDeleteAccount_WithProfilePicture verifies that the S3 profile picture
// deletion goroutine is triggered when profile_pic_url is set.
func TestDeleteAccount_WithProfilePicture(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)
	userID, err := fixtures.CreateTestUser(tx)
	require.NoError(t, err)

	// Set profile_pic_url on the user to trigger S3 deletion goroutine
	_, err = tx.Exec(ctx, `UPDATE users SET profile_pic_url = 'https://cdn.example.com/pics/old.jpg' WHERE id = $1`, userID)
	require.NoError(t, err)

	handler := http.HandlerFunc(DeleteAccountHandler)
	req := httptest.NewRequest("DELETE", "/api/user/account", nil)
	req = req.WithContext(context.WithValue(ctx, mw.UserIDKey, userID))
	w := httptest.NewRecorder()
	handler.ServeHTTP(w, req)

	// Handler returns 204 regardless of goroutine result
	assert.Equal(t, http.StatusNoContent, w.Code)
	// Best-effort wait for background goroutine to initiate
	time.Sleep(50 * time.Millisecond)
}

// =============================================================================
// DeleteAccountHandler — Square goroutine coverage
// =============================================================================

// TestDeleteAccount_WithSquareClient verifies that the Square saved card
// cleanup goroutine is triggered when SquareClient is set.
func TestDeleteAccount_WithSquareClient(t *testing.T) {
	// Save and restore SquareClient
	savedSquareClient := payments.SquareClient
	payments.SquareClient = square.NewDevClient()
	t.Cleanup(func() { payments.SquareClient = savedSquareClient })

	ctx, tx := testutils.SetupTestTx(t)
	userID, err := fixtures.CreateTestUser(tx)
	require.NoError(t, err)

	handler := http.HandlerFunc(DeleteAccountHandler)
	req := httptest.NewRequest("DELETE", "/api/user/account", nil)
	req = req.WithContext(context.WithValue(ctx, mw.UserIDKey, userID))
	w := httptest.NewRecorder()
	handler.ServeHTTP(w, req)

	assert.Equal(t, http.StatusNoContent, w.Code)
	// Best-effort wait for background goroutine to initiate
	time.Sleep(50 * time.Millisecond)
}

// =============================================================================
// DeleteAccountHandler — Square ccof redaction + customer deletion
// =============================================================================

// syncBuffer is a mutex-guarded log/slog writer so logs written by background
// goroutines can be read safely under -race.
type syncBuffer struct {
	mu  sync.Mutex
	buf bytes.Buffer
}

func (b *syncBuffer) Write(p []byte) (int, error) {
	b.mu.Lock()
	defer b.mu.Unlock()
	return b.buf.Write(p)
}

func (b *syncBuffer) String() string {
	b.mu.Lock()
	defer b.mu.Unlock()
	return b.buf.String()
}

// recordingSquareClient records Square erasure calls made by the account
// deletion goroutine so tests can assert what was (and wasn't) called.
type recordingSquareClient struct {
	square.SquareClient
	mu               sync.Mutex
	deletedCards     []string
	deletedCustomers []string
}

func (c *recordingSquareClient) DeleteCardOnFile(ctx context.Context, cardID string) error {
	c.mu.Lock()
	c.deletedCards = append(c.deletedCards, cardID)
	c.mu.Unlock()
	// Token-free error so the log-redaction test isolates redaction of the
	// cardID argument rather than the error string.
	return fmt.Errorf("square: network error disabling card at Square")
}

func (c *recordingSquareClient) DeleteCustomer(ctx context.Context, customerID string) error {
	c.mu.Lock()
	c.deletedCustomers = append(c.deletedCustomers, customerID)
	c.mu.Unlock()
	return nil
}

func (c *recordingSquareClient) cardDeletes() []string {
	c.mu.Lock()
	defer c.mu.Unlock()
	return append([]string(nil), c.deletedCards...)
}

func (c *recordingSquareClient) customerDeletes() []string {
	c.mu.Lock()
	defer c.mu.Unlock()
	return append([]string(nil), c.deletedCustomers...)
}

// TestDeleteAccount_LogsRedactCardTokens verifies the account-deletion
// goroutine logs a redacted tokenPrefix form of ccof: card IDs, never the full
// token (SECURITY: full ccof tokens must not reach server logs).
func TestDeleteAccount_LogsRedactCardTokens(t *testing.T) {
	savedSquareClient := payments.SquareClient
	rec := &recordingSquareClient{SquareClient: square.NewDevClient()}
	payments.SquareClient = rec
	t.Cleanup(func() { payments.SquareClient = savedSquareClient })

	var sb syncBuffer
	log.SetOutput(&sb)
	defer log.SetOutput(os.Stderr)

	ctx, tx := testutils.SetupTestTx(t)
	userID, err := fixtures.CreateTestUser(tx)
	require.NoError(t, err)

	fullToken := "ccof:secret_token_abc123"
	_, err = tx.Exec(ctx, `
		INSERT INTO user_saved_cards (user_id, square_card_id, square_customer_id, brand, last_4, exp_month, exp_year, fingerprint, is_default)
		VALUES ($1, $2, 'cus_secret_abc123', 'Visa', '4242', 12, 2030, 'fp1', true)
	`, userID, fullToken)
	require.NoError(t, err)

	handler := http.HandlerFunc(DeleteAccountHandler)
	req := httptest.NewRequest(http.MethodDelete, "/api/user/account", nil)
	req = req.WithContext(context.WithValue(ctx, mw.UserIDKey, userID))
	w := httptest.NewRecorder()
	handler.ServeHTTP(w, req)
	require.Equal(t, http.StatusNoContent, w.Code)

	require.Eventually(t, func() bool {
		return len(rec.cardDeletes()) > 0
	}, 5*time.Second, 10*time.Millisecond, "expected the Square cleanup goroutine to attempt card deletion")

	// The card-deletion log is written by the async goroutine AFTER the call
	// returns — wait for the redacted prefix to appear instead of racing the
	// goroutine (the cleanup now dispatches after the local tx commits).
	require.Eventually(t, func() bool {
		return strings.Contains(sb.String(), "ccof:sec...")
	}, 5*time.Second, 10*time.Millisecond, "expected the redacted token prefix to reach the logs")

	logs := sb.String()
	if strings.Contains(logs, fullToken) {
		t.Errorf("full ccof token %q leaked into logs: %q", fullToken, logs)
	}
}

// TestDeleteAccount_DeletesSquareCustomerOnce verifies the Square customer
// profile (email/name PII) is deleted exactly once even when multiple saved
// cards share the same square_customer_id.
func TestDeleteAccount_DeletesSquareCustomerOnce(t *testing.T) {
	savedSquareClient := payments.SquareClient
	rec := &recordingSquareClient{SquareClient: square.NewDevClient()}
	payments.SquareClient = rec
	t.Cleanup(func() { payments.SquareClient = savedSquareClient })

	ctx, tx := testutils.SetupTestTx(t)
	userID, err := fixtures.CreateTestUser(tx)
	require.NoError(t, err)

	for _, cardTok := range []string{"ccof:card_one_123", "ccof:card_two_456"} {
		_, err := tx.Exec(ctx, `
			INSERT INTO user_saved_cards (user_id, square_card_id, square_customer_id, brand, last_4, exp_month, exp_year, fingerprint, is_default)
			VALUES ($1, $2, 'cus_shared_123', 'Visa', '4242', 12, 2030, 'fp1', true)
		`, userID, cardTok)
		require.NoError(t, err)
	}

	handler := http.HandlerFunc(DeleteAccountHandler)
	req := httptest.NewRequest(http.MethodDelete, "/api/user/account", nil)
	req = req.WithContext(context.WithValue(ctx, mw.UserIDKey, userID))
	w := httptest.NewRecorder()
	handler.ServeHTTP(w, req)
	require.Equal(t, http.StatusNoContent, w.Code)

	require.Eventually(t, func() bool {
		return len(rec.customerDeletes()) > 0
	}, 5*time.Second, 10*time.Millisecond, "expected DeleteCustomer to be called")

	require.Equal(t, []string{"cus_shared_123"}, rec.customerDeletes(), "a shared Square customer must be deleted exactly once")
	require.ElementsMatch(t, []string{"ccof:card_one_123", "ccof:card_two_456"}, rec.cardDeletes(), "both saved cards must be disabled at Square")
}

// =============================================================================
// DeleteAccountHandler — Square cleanup only after local tx commit
// =============================================================================

// TestDeleteAccount_SquareCleanupNotDispatchedOnTxFailure verifies the fix that
// dispatches the Square cleanup goroutine only AFTER the local
// anonymization/deletion transaction commits: when the local tx fails (here an
// admin_notifications row references the guest with a RESTRICT FK, so
// delete_guest_user's DELETE FROM users errors), DeleteCardOnFile/DeleteCustomer
// must NOT be called — a failed local tx leaves external state intact for retry.
func TestDeleteAccount_SquareCleanupNotDispatchedOnTxFailure(t *testing.T) {
	savedSquareClient := payments.SquareClient
	rec := &recordingSquareClient{SquareClient: square.NewDevClient()}
	payments.SquareClient = rec
	t.Cleanup(func() { payments.SquareClient = savedSquareClient })

	ctx, tx := testutils.SetupTestTx(t)

	guestID, err := fixtures.CreateTestGuestUser(tx)
	require.NoError(t, err)

	// Saved card so the pre-tx snapshot captures a card/customer to scrub — if
	// the goroutine were (wrongly) dispatched before the tx, it would record a
	// call here.
	_, err = tx.Exec(ctx, `
		INSERT INTO user_saved_cards (user_id, square_card_id, square_customer_id, brand, last_4, exp_month, exp_year, fingerprint, is_default)
		VALUES ($1, $2, 'cus_fail_tx_123', 'Visa', '4242', 12, 2030, 'fp1', true)
	`, guestID, "ccof:card_fail_tx")
	require.NoError(t, err)

	// admin_notifications.user_id has a RESTRICT FK on users(id): seeding a row
	// makes delete_guest_user's DELETE FROM users fail, so the local tx errors.
	_, err = tx.Exec(ctx, `
		INSERT INTO admin_notifications (reason, user_id)
		VALUES ('pending_booking', $1)
	`, guestID)
	require.NoError(t, err)

	handler := http.HandlerFunc(DeleteAccountHandler)
	req := httptest.NewRequest(http.MethodDelete, "/api/user/account", nil)
	req = req.WithContext(context.WithValue(ctx, mw.UserIDKey, guestID))
	w := httptest.NewRecorder()
	handler.ServeHTTP(w, req)

	require.Equal(t, http.StatusInternalServerError, w.Code, "the failed local tx must surface a 500")

	// Give a (wrongly dispatched) cleanup goroutine time to record its calls.
	time.Sleep(100 * time.Millisecond)
	require.Equal(t, 0, len(rec.cardDeletes()), "DeleteCardOnFile must NOT be called when the local tx failed")
	require.Equal(t, 0, len(rec.customerDeletes()), "DeleteCustomer must NOT be called when the local tx failed")
}

// =============================================================================
// DeleteAccountHandler — shared Square customer edge (cross-user email dedup)
// =============================================================================

// TestDeleteAccount_SkipsSharedSquareCustomer verifies the fix that guards
// DeleteCustomer behind a "still referenced by another account" check: Square
// customers are provisioned per-user from a deterministic email-derived key,
// but the UNIQUE(email) index excludes guest accounts, so a guest and a
// registered user sharing an email can land on the SAME Square customer profile
// (Square dedups within its idempotency window). Deleting one account must NOT
// delete the shared profile — the other account's saved-card charges would
// break. The other user's saved-card row must be left untouched.
func TestDeleteAccount_SkipsSharedSquareCustomer(t *testing.T) {
	savedSquareClient := payments.SquareClient
	rec := &recordingSquareClient{SquareClient: square.NewDevClient()}
	payments.SquareClient = rec
	t.Cleanup(func() { payments.SquareClient = savedSquareClient })

	ctx, tx := testutils.SetupTestTx(t)

	userA, err := fixtures.CreateTestUser(tx)
	require.NoError(t, err)
	userB, err := fixtures.CreateTestUser(tx)
	require.NoError(t, err)

	for _, tc := range []struct{ userID, cardID string }{
		{userA, "ccof:card_user_a"},
		{userB, "ccof:card_user_b"},
	} {
		_, err := tx.Exec(ctx, `
			INSERT INTO user_saved_cards (user_id, square_card_id, square_customer_id, brand, last_4, exp_month, exp_year, fingerprint, is_default)
			VALUES ($1, $2, 'cus_shared_cross_user', 'Visa', '4242', 12, 2030, 'fp1', true)
		`, tc.userID, tc.cardID)
		require.NoError(t, err)
	}

	// Commit the setup so the cleanup goroutine's pool-level reference check
	// (background context, outside the per-test tx) can see user B's row.
	pgxTx := db.TxFromContext(ctx)
	require.NotNil(t, pgxTx, "no transaction in context")
	require.NoError(t, pgxTx.Commit(ctx))

	// The committed rows live in the SHARED test pool — clean them up.
	t.Cleanup(func() {
		_, _ = db.Conn.Exec(context.Background(), `DELETE FROM user_saved_cards WHERE square_customer_id = 'cus_shared_cross_user'`)
		_, _ = db.Conn.Exec(context.Background(), `DELETE FROM users WHERE id IN ($1, $2)`, userA, userB)
	})

	handler := http.HandlerFunc(DeleteAccountHandler)
	req := httptest.NewRequest(http.MethodDelete, "/api/user/account", nil)
	req = req.WithContext(context.WithValue(context.Background(), mw.UserIDKey, userA))
	w := httptest.NewRecorder()
	handler.ServeHTTP(w, req)
	require.Equal(t, http.StatusNoContent, w.Code)

	// The goroutine runs the card loop first — wait for it to record user A's
	// card deletion so we know the cleanup ran, then assert the shared customer
	// was NOT deleted.
	require.Eventually(t, func() bool {
		return len(rec.cardDeletes()) > 0
	}, 5*time.Second, 10*time.Millisecond, "expected the Square cleanup goroutine to attempt card deletion")

	require.Never(t, func() bool {
		return len(rec.customerDeletes()) > 0
	}, 500*time.Millisecond, 10*time.Millisecond, "DeleteCustomer must NOT be called for a Square customer still referenced by another account")

	// User B's saved card is untouched (still references the shared customer).
	var bUserID string
	var bCustomerID sql.NullString
	var bDeletedAt sql.NullTime
	err = db.Conn.QueryRow(context.Background(), `
		SELECT user_id, square_customer_id, deleted_at FROM user_saved_cards WHERE square_card_id = 'ccof:card_user_b'
	`).Scan(&bUserID, &bCustomerID, &bDeletedAt)
	require.NoError(t, err)
	require.Equal(t, userB, bUserID)
	require.True(t, bCustomerID.Valid && bCustomerID.String == "cus_shared_cross_user", "user B's row must keep the shared square_customer_id")
	require.False(t, bDeletedAt.Valid, "user B's row must not be soft-deleted")
}

// =============================================================================
// DeleteAccountHandler — process-local Square customer cache invalidation
// =============================================================================

// TestDeleteAccount_InvalidatesSquareCustomerCache verifies the GDPR erasure
// flow drops the user's process-local Square customer cache entry: after
// DeleteAccountHandler anonymizes the account (NULLing square_customer_id on
// saved cards and deleting the customer at Square), a later save-card flow for
// the same (anonymized) user must re-mint a fresh Square customer instead of
// reusing the deleted one's stale cached id.
func TestDeleteAccount_InvalidatesSquareCustomerCache(t *testing.T) {
	savedSquareClient := payments.SquareClient
	payments.SquareClient = square.NewDevClient()
	t.Cleanup(func() { payments.SquareClient = savedSquareClient })

	ctx, tx := testutils.SetupTestTx(t)
	userID, err := fixtures.CreateTestUser(tx)
	require.NoError(t, err)

	// A saved card gives the provisioning path a persistence point.
	_, err = tx.Exec(ctx, `
		INSERT INTO user_saved_cards (user_id, square_card_id, brand, last_4, exp_month, exp_year, fingerprint, is_default)
		VALUES ($1, 'ccof:cache_erasure_card', 'Visa', '4242', 12, 2030, 'fp1', true)
	`, userID)
	require.NoError(t, err)
	t.Cleanup(func() { payments.InvalidateSquareCustomerCache(userID) })

	svc := payments.NewPaymentService()
	originalID, err := svc.EnsureSquareCustomer(ctx, userID)
	require.NoError(t, err)
	require.NotEmpty(t, originalID, "a Square customer must be provisioned and cached for the save-card user")

	handler := http.HandlerFunc(DeleteAccountHandler)
	req := httptest.NewRequest(http.MethodDelete, "/api/user/account", nil)
	req = req.WithContext(context.WithValue(ctx, mw.UserIDKey, userID))
	w := httptest.NewRecorder()
	handler.ServeHTTP(w, req)
	require.Equal(t, http.StatusNoContent, w.Code)

	// The account is anonymized (email → anon-{id}@anon.invalid) and
	// square_customer_id is NULLed; the handler must also have invalidated the
	// process-local cache. A subsequent ensureSquareCustomer therefore
	// re-queries the NULLed DB and mints a fresh customer from the anonymized
	// email — a different id. Without the invalidation it would return the
	// stale originalID, resurrecting the erased identity in memory.
	reprovisioned, err := svc.EnsureSquareCustomer(ctx, userID)
	require.NoError(t, err)
	require.NotEqual(t, originalID, reprovisioned, "an erased user must not reuse the deleted Square customer id from the cache")
}