//go:build test && dev

package payments

// =============================================================================
// LOOP A — fresh-review money findings (HIGH-1, HIGH-2, MEDIUM-3, MEDIUM-5,
// LOW-6). Each test pins the fixed behaviour and would fail on the old code.
// =============================================================================

import (
	"context"
	"net/http"
	"testing"
	"time"

	"crussell/db"
	"crussell/internal/square"
	"crussell/testutils"
	"crussell/testutils/fixtures"
	"crussell/testutils/jwt"

	"github.com/jackc/pgx/v5"
	"github.com/stretchr/testify/assert"
	"github.com/stretchr/testify/require"
)

// =============================================================================
// HIGH-1 — the overflow→tip guard compares chargeAmount (what Square will
// actually charge and buildSplitRecords will split), not req.Amount against an
// inflated remaining+discount threshold. A pending campaign credit previously
// let a full payment exceed the REAL remaining and silently mint a pre-start
// tip.
// =============================================================================

// TestLoopA_PreStartFullWithPendingDiscount_RequiresConfirmation locks the HIGH-1
// bypass: a full £60 payment on the £50 fixture booking with a 100% campaign
// eligible (£50 credit) would have passed the old guard (60 < 50+50) and
// silently charged £60, carving a £10 pre-start tip with no confirmation.
// chargeAmount == req.Amount for a 'full' payment, so it exceeds the real £50
// remaining and MUST require confirmation.
func TestLoopA_PreStartFullWithPendingDiscount_RequiresConfirmation(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	userID, bookingID, _ := setupTestData(t, ctx, tx)
	userToken := jwt.GenerateUserToken(userID)
	seedActiveCampaign(t, ctx, tx, 100)

	cardToken := "cnon:loop-a-overflow-full"
	req := CreateBookingPaymentRequest{
		Amount:         6000, // £60 on a £50 booking
		PaymentType:    "full",
		NewCardToken:   &cardToken,
		IdempotencyKey: "loop-a-overflow-full-" + bookingID,
	}

	handler := CreateBookingPayment
	w := makePaymentRequest(handler, "POST", "/api/bookings/"+bookingID+"/payment", req, userToken, ctx)
	require.Equal(t, http.StatusBadRequest, w.Code, "a full payment beyond the real remaining must require confirmation even with a discount pending, body: %s", w.Body.String())
	assert.Contains(t, w.Body.String(), "overflow_tip_confirmation_required")

	// No payment record may be written for the rejected overflow.
	var payCount int
	require.NoError(t, tx.QueryRow(ctx, `SELECT COUNT(*) FROM payments WHERE booking_id = $1`, bookingID).Scan(&payCount))
	assert.Zero(t, payCount, "the unconfirmed overflow must not create any payment record")
}

// TestLoopA_PreStartDepositWithDiscount_OverflowRequiresConfirmation locks the
// Loop-B A6 finding on the HIGH-1 deposit side: a deposit-with-discount charge
// is clamped DOWN to the discounted obligation (remaining − discount), and the
// overflow guard compares the RAW request against that obligation. A £60
// deposit on the £50 booking with a 20% campaign (£10 credit) requests £60
// against a £40 discounted obligation — it MUST require confirmation (the old
// guard compared the discounted charge against the real £50 remaining, accepted
// it and silently truncated the discount). On confirmation the full £60 is
// charged and the £10 excess (beyond the real remaining) is carved out as a tip
// record — never absorbed as service revenue.
func TestLoopA_PreStartDepositWithDiscount_OverflowRequiresConfirmation(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	userID, bookingID, _ := setupTestData(t, ctx, tx)
	userToken := jwt.GenerateUserToken(userID)
	seedActiveCampaign(t, ctx, tx, 20)

	cardToken := "cnon:loop-a-deposit-overflow"
	req := CreateBookingPaymentRequest{
		Amount:         6000, // £60 deposit; discounted obligation is £40
		PaymentType:    "deposit",
		NewCardToken:   &cardToken,
		IdempotencyKey: "loop-a-deposit-overflow-" + bookingID,
	}

	handler := CreateBookingPayment
	w := makePaymentRequest(handler, "POST", "/api/bookings/"+bookingID+"/payment", req, userToken, ctx)
	require.Equal(t, http.StatusBadRequest, w.Code, "a deposit beyond the discounted obligation must require confirmation, body: %s", w.Body.String())
	assert.Contains(t, w.Body.String(), "overflow_tip_confirmation_required")

	// No payment record may be written for the unconfirmed overflow.
	var payCount int
	require.NoError(t, tx.QueryRow(ctx, `SELECT COUNT(*) FROM payments WHERE booking_id = $1`, bookingID).Scan(&payCount))
	assert.Zero(t, payCount, "the unconfirmed overflow must not create any payment record")

	// Confirmed: the full £60 is charged and the £10 excess (60 − 50 real
	// remaining) is carved out as a tip record, never absorbed as service
	// revenue.
	req.ConfirmOverflowTip = true
	w2 := makePaymentRequest(handler, "POST", "/api/bookings/"+bookingID+"/payment", req, userToken, ctx)
	require.Equal(t, http.StatusOK, w2.Code, "a confirmed deposit overflow must proceed, body: %s", w2.Body.String())

	var bookingPortion float64
	require.NoError(t, tx.QueryRow(ctx, `SELECT COALESCE(SUM(amount), 0) FROM payments WHERE booking_id = $1 AND status = 'completed' AND payment_type != 'tip'`, bookingID).Scan(&bookingPortion))
	assert.InDelta(t, 50.0, bookingPortion, 0.001, "the booking portion must total the £50 obligation")

	var tipCount int
	var tipAmount float64
	require.NoError(t, tx.QueryRow(ctx, `SELECT COUNT(*), COALESCE(SUM(amount), 0) FROM payments WHERE booking_id = $1 AND status = 'completed' AND payment_type = 'tip'`, bookingID).Scan(&tipCount, &tipAmount))
	assert.Equal(t, 1, tipCount, "the £10 excess must be carved out as a tip record")
	assert.InDelta(t, 10.0, tipAmount, 0.001, "the tip must equal the £10 excess")
}

// =============================================================================
// HIGH-2 — a deposit-with-discount pending-reuse retry must compare against the
// CHARGE amount stored on the pending row (the discounted amount), not the raw
// req.Amount the frontend resends. Previously every such retry 400'd
// "amount_mismatch" forever.
// =============================================================================

// TestLoopA_DepositWithDiscount_PendingReuseRetry_Succeeds seeds the pending
// row at the DISCOUNTED charge (£15 = £25 deposit − £10 campaign credit) and
// retries with the RAW £25 deposit — exactly what the frontend resends. The
// retry must be accepted (chargeAmount recomputes to £15 and matches) and the
// charge completed, not rejected with amount_mismatch.
func TestLoopA_DepositWithDiscount_PendingReuseRetry_Succeeds(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	userID, bookingID, _ := setupTestData(t, ctx, tx)
	userToken := jwt.GenerateUserToken(userID)
	// 20% campaign on the £50 fixture booking = £10 credit → a £25 raw deposit
	// charges £15.
	seedActiveCampaign(t, ctx, tx, 20)

	key := "loop-a-deposit-retry-" + bookingID
	// Seed the pending row exactly as the handler's first attempt stored it:
	// the CHARGE amount (£15), not the requested £25.
	_, err := tx.Exec(ctx, `
		INSERT INTO payments (booking_id, payment_type, payment_method, status, amount, idempotency_key, square_source_id, created_at, updated_at, created_by)
		VALUES ($1, 'deposit', 'online_square', 'pending', 15.00, $2, 'cnon:first-attempt', NOW(), NOW(), $3)
	`, bookingID, key, userID)
	require.NoError(t, err)

	cardToken := "cnon:loop-a-deposit-retry"
	req := CreateBookingPaymentRequest{
		Amount:         2500, // raw £25 deposit — the frontend resends this
		PaymentType:    "deposit",
		NewCardToken:   &cardToken,
		IdempotencyKey: key,
	}

	handler := CreateBookingPayment
	w := makePaymentRequest(handler, "POST", "/api/bookings/"+bookingID+"/payment", req, userToken, ctx)
	require.Equal(t, http.StatusOK, w.Code, "a deposit-with-discount pending-reuse retry must succeed, body: %s", w.Body.String())

	var status, sqPayID string
	require.NoError(t, tx.QueryRow(ctx, `SELECT status, COALESCE(square_payment_id, '') FROM payments WHERE idempotency_key = $1`, key).Scan(&status, &sqPayID))
	assert.Equal(t, "completed", status, "the reused pending row must complete")
	assert.NotEmpty(t, sqPayID, "the completed row must carry the Square payment id")

	// Exactly one row for the key — the pending row was reused, not duplicated.
	var payCount int
	require.NoError(t, tx.QueryRow(ctx, `SELECT COUNT(*) FROM payments WHERE idempotency_key = $1`, key).Scan(&payCount))
	assert.Equal(t, 1, payCount, "the retry must reuse the pending row, not mint a second one")
}

// =============================================================================
// MEDIUM-3 — the stale-pending sweep rescue must mirror the live-path split: an
// overflow beyond the booking's remaining obligation is carved out as a tip
// record (never mis-booked as service revenue) and the fully-paid completion
// check runs.
// =============================================================================

// TestLoopA_SweepRescue_CarvesTipAndCompletes rescues a keyed lost-response
// payment of £60 on the £50 fixture booking via the sweep. The rescue must:
// complete the row, split it into deposit £25 + balance £25 + a carved tip £10,
// and complete the booking (fully paid).
func TestLoopA_SweepRescue_CarvesTipAndCompletes(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	userID, err := fixtures.CreateTestUser(tx)
	require.NoError(t, err)
	serviceID, err := fixtures.CreateTestService(tx)
	require.NoError(t, err)
	bookingID, err := fixtures.CreateTestBookingAtTime(tx, userID, serviceID,
		time.Date(2099, 12, 31, 10, 0, 0, 0, time.UTC))
	require.NoError(t, err)

	staleID, err := fixtures.CreateTestPayment(tx, bookingID, 60.00, "online_square", "full", "pending")
	require.NoError(t, err)
	const key = "loop-a-sweep-rescue"
	_, err = tx.Exec(ctx, "UPDATE payments SET created_at = NOW() - INTERVAL '23 hours', idempotency_key = $1, square_source_id = 'cnon:loop-a' WHERE id = $2", key, staleID)
	require.NoError(t, err)

	origClient := SquareClient
	mock := square.NewDevClient().(*square.MockClient)
	pay, err := mock.CreatePayment(context.Background(), square.CreatePaymentReq{
		Amount:         6000,
		Currency:       "GBP",
		SourceID:       "cnon:loop-a",
		IdempotencyKey: key,
	})
	require.NoError(t, err, "failed to seed the completed Square payment")
	SquareClient = mock
	defer func() { SquareClient = origClient }()

	pgxTx := db.TxFromContext(ctx)
	require.NotNil(t, pgxTx, "no transaction in context")
	require.NoError(t, pgxTx.Commit(ctx), "failed to commit test tx")

	t.Cleanup(func() {
		_, _ = db.Conn.Exec(context.Background(), `DELETE FROM payments WHERE id = $1`, staleID)
		_, _ = db.Conn.Exec(context.Background(), `DELETE FROM bookings WHERE id = $1`, bookingID)
		_, _ = db.Conn.Exec(context.Background(), `DELETE FROM services WHERE id = $1`, serviceID)
		_, _ = db.Conn.Exec(context.Background(), `DELETE FROM users WHERE id = $1`, userID)
	})

	freshCtx := context.Background()
	if _, err := SweepStalePendingPayments(freshCtx); err != nil {
		t.Fatalf("sweep failed: %v", err)
	}

	var status, sqPayID string
	require.NoError(t, db.Conn.QueryRow(freshCtx, "SELECT status, COALESCE(square_payment_id, '') FROM payments WHERE id = $1", staleID).Scan(&status, &sqPayID))
	assert.Equal(t, "completed", status, "the rescued row must complete")
	assert.Equal(t, pay.SquarePayID, sqPayID, "the rescued row must carry the replayed square_payment_id")

	// The primary row is the deposit portion (£25); the balance and tip are
	// separate split rows.
	var bookingPortion float64
	require.NoError(t, db.Conn.QueryRow(freshCtx, `SELECT COALESCE(SUM(amount), 0) FROM payments WHERE booking_id = $1 AND status = 'completed' AND payment_type != 'tip'`, bookingID).Scan(&bookingPortion))
	assert.InDelta(t, 50.0, bookingPortion, 0.001, "the booking portion must total the £50 obligation (no overflow mis-booked as service revenue)")

	var tipCount int
	var tipAmount float64
	require.NoError(t, db.Conn.QueryRow(freshCtx, `SELECT COUNT(*), COALESCE(SUM(amount), 0) FROM payments WHERE booking_id = $1 AND status = 'completed' AND payment_type = 'tip'`, bookingID).Scan(&tipCount, &tipAmount))
	assert.Equal(t, 1, tipCount, "the £10 overflow must be carved out as a tip record")
	assert.InDelta(t, 10.0, tipAmount, 0.001, "the tip must equal the £10 overflow")

	// The booking was fully paid by the rescue → completed.
	var bookingStatus string
	require.NoError(t, db.Conn.QueryRow(freshCtx, `SELECT status FROM bookings WHERE id = $1`, bookingID).Scan(&bookingStatus))
	assert.Equal(t, "completed", bookingStatus, "the fully-paid rescue must run the completion side-effects")
}

// =============================================================================
// MEDIUM-5 — the till gift-card create/top-up must go through the same £5,000/
// day admin cap as the admin API surface. The till's own same-day value counts.
// =============================================================================

// TestLoopA_TillGiftCard_DailyCap_Enforced seeds a till_sales row of £4,800
// created by the admin today and verifies a £250 till create is rejected 400
// (would land the day on £5,050 — over the cap; £250 is at the per-transaction
// limit so the daily check is what fires) while a £200 create lands exactly on
// the £5,000 cap and succeeds — pinning the cap as inclusive and the till's own
// value as counted.
func TestLoopA_TillGiftCard_DailyCap_Enforced(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	adminID, err := fixtures.CreateTestAdminUser(tx)
	require.NoError(t, err)
	adminToken := jwt.GenerateTestToken(adminID, "admin")

	// A gift card created BEFORE today that the admin topped up at the till
	// today for £4,800 — the seeded till_sales row is the day's issued value.
	var cardID string
	require.NoError(t, tx.QueryRow(ctx, `
		INSERT INTO gift_cards (total_funds_added, amount_remaining, created_by, created_at)
		VALUES (4800.00, 4800.00, $1, NOW() - INTERVAL '1 day') RETURNING id
	`, adminID).Scan(&cardID))
	_, err = tx.Exec(ctx, `
		INSERT INTO till_sales (item_type, item_id, description, quantity, unit_price, total_amount,
			payment_method, status, idempotency_key, created_by, created_at, updated_at)
		VALUES ('gift_card', $1, 'Gift Card topup', 1, 4800.00, 4800.00, 'cash', 'completed',
			'loop-a-till-seed', $2, NOW(), NOW())
	`, cardID, adminID)
	require.NoError(t, err)

	// £250 (the per-transaction maximum) would land the day on £5,050 — over
	// the £5,000 daily cap.
	over := makeTillSaleRequest(t, TillSaleRequest{
		ItemType:       "gift_card",
		Action:         "create",
		Amount:         250.00,
		PaymentMethod:  "cash",
		IdempotencyKey: "loop-a-till-over",
	}, adminToken, ctx, tx.(pgx.Tx))
	require.Equal(t, http.StatusBadRequest, over.Code, "body: %s", over.Body.String())
	assert.Contains(t, over.Body.String(), "£5,000", "the rejection must cite the daily cap")
	assert.Contains(t, over.Body.String(), "daily", "the rejection must be the daily-limit message")

	// £200 lands the day on EXACTLY £5,000 — inside the cap (inclusive).
	ok := makeTillSaleRequest(t, TillSaleRequest{
		ItemType:       "gift_card",
		Action:         "create",
		Amount:         200.00,
		PaymentMethod:  "cash",
		IdempotencyKey: "loop-a-till-ok",
	}, adminToken, ctx, tx.(pgx.Tx))
	require.Equal(t, http.StatusCreated, ok.Code, "boundary body: %s", ok.Body.String())
}

// =============================================================================
// LOW-6 — expiry is enforced at redemption, not just by the nightly cleanup
// job: a card whose expiry_date has passed cannot be redeemed even before the
// next CleanupExpiredGiftCards run.
// =============================================================================

// TestLoopA_RedeemExpiredCard_Rejected redeems a card whose expiry_date is in
// the past but whose amount_remaining is still live (the nightly job has not
// run yet). The redemption must be rejected 400 and the card left untouched.
func TestLoopA_RedeemExpiredCard_Rejected(t *testing.T) {
	ctx, tx := testutils.SetupTestTx(t)

	userID, err := fixtures.CreateTestUser(tx)
	require.NoError(t, err)
	token := jwt.GenerateTestToken(userID, "verified_email")

	var cardID string
	require.NoError(t, tx.QueryRow(ctx, `
		INSERT INTO gift_cards (total_funds_added, amount_remaining, expiry_date)
		VALUES (20.00, 20.00, NOW() - INTERVAL '1 day') RETURNING id
	`).Scan(&cardID))

	w := redeemCodeRequest(t, token, tx.(pgx.Tx), cardID)
	require.Equal(t, http.StatusBadRequest, w.Code, "an expired card must not be redeemable, body: %s", w.Body.String())
	assert.Contains(t, w.Body.String(), "expired")

	// The card is untouched: balance live, not redeemed, no balance credited.
	var remaining float64
	var redeemedBy interface{}
	require.NoError(t, tx.QueryRow(ctx, `SELECT amount_remaining, redeemed_by FROM gift_cards WHERE id = $1`, cardID).Scan(&remaining, &redeemedBy))
	assert.Equal(t, 20.0, remaining, "the expired card's balance must be left untouched")
	assert.Nil(t, redeemedBy, "the expired card must not be marked redeemed")

	var balanceCount int
	require.NoError(t, tx.QueryRow(ctx, `SELECT COUNT(*) FROM user_giftcard_balances WHERE user_id = $1`, userID).Scan(&balanceCount))
	assert.Zero(t, balanceCount, "no balance may be credited from an expired card")
}