//go:build test

package webhooks

// Round 7 regression tests — webhook money paths found at 0% coverage:
//
// (a) handleDisputeStateUpdated's findPaymentByDisputeID fallback when a
//     dispute.state.updated payload carries no resolvable Square payment id.
// (b) clawbackOneTillSale's non-gift-card branch (a definitively-failed charge
//     marks the till sale failed WITHOUT reversing any gift-card funding).
// (c) handleDisputeEvidence / handleTerminalCheckout — informational dispatch
//     paths that must complete 200 + log without mutating state.

import (
	"bytes"
	"context"
	"encoding/json"
	"log"
	"net/http"
	"strings"
	"testing"

	"crussell/db"
	"crussell/testutils/fixtures"
)

// =============================================================================
// Helpers
// =============================================================================

// createWebhookTestGiftCard inserts a funded gift card and returns its id.
func createWebhookTestGiftCard(t *testing.T, amount float64) string {
	t.Helper()
	adminID, err := fixtures.CreateTestAdminUser(db.Conn)
	if err != nil {
		t.Fatalf("failed to create admin user: %v", err)
	}
	var id string
	if err := db.Conn.QueryRow(context.Background(), `
		INSERT INTO gift_cards (total_funds_added, amount_remaining, created_by, is_inventory, voucher_type_at_purchase)
		VALUES ($1, $1, $2, FALSE, 'SPV')
		RETURNING id
	`, amount, adminID).Scan(&id); err != nil {
		t.Fatalf("failed to create gift card: %v", err)
	}
	return id
}

// createWebhookTestTillSale inserts a pending till sale with the given item
// type and item id (nil for a NULL item_id) and returns the sale id.
func createWebhookTestTillSale(t *testing.T, squarePaymentID, itemType string, itemID any) string {
	t.Helper()
	adminID, err := fixtures.CreateTestAdminUser(db.Conn)
	if err != nil {
		t.Fatalf("failed to create admin user: %v", err)
	}
	var saleID string
	if err := db.Conn.QueryRow(context.Background(), `
		INSERT INTO till_sales (item_type, item_id, description, quantity, unit_price, total_amount,
			payment_method, status, square_payment_id, created_by, created_at, updated_at)
		VALUES ($1, $2, 'webhook round7 test', 1, 40.00, 40.00, 'online_square', 'pending',
			$3, $4, NOW(), NOW())
		RETURNING id
	`, itemType, itemID, squarePaymentID, adminID).Scan(&saleID); err != nil {
		t.Fatalf("failed to create pending till sale: %v", err)
	}
	return saleID
}

// createWebhookTestBookingPayment creates a completed payment bound to a fresh
// booking and returns the local payment id and booking id. A booking-scoped
// payment makes the critical-notification assertions below attributable to one
// booking, so they cannot race with other tests' NULL-booking rows.
func createWebhookTestBookingPayment(t *testing.T) (payID, bookingID string) {
	t.Helper()
	userID, err := fixtures.CreateTestUser(db.Conn)
	if err != nil {
		t.Fatalf("failed to create test user: %v", err)
	}
	serviceID, err := fixtures.CreateTestService(db.Conn)
	if err != nil {
		t.Fatalf("failed to create test service: %v", err)
	}
	bookingID, err = fixtures.CreateTestBooking(db.Conn, userID, serviceID)
	if err != nil {
		t.Fatalf("failed to create test booking: %v", err)
	}
	payID, err = fixtures.CreateTestPayment(db.Conn, bookingID, 10.00, "online_square", "full", "completed")
	if err != nil {
		t.Fatalf("failed to create test payment: %v", err)
	}
	return payID, bookingID
}

// countUnackedCriticalNotificationsForBooking returns the number of
// unacknowledged critical_payment_log notifications for a booking.
func countUnackedCriticalNotificationsForBooking(t *testing.T, bookingID string) int {
	t.Helper()
	var n int
	if err := db.Conn.QueryRow(context.Background(), `
		SELECT COUNT(*) FROM admin_notifications
		WHERE reason = 'critical_payment_log' AND booking_id = $1 AND acknowledged_at IS NULL
	`, bookingID).Scan(&n); err != nil {
		t.Fatalf("failed to count critical notifications for booking %s: %v", bookingID, err)
	}
	return n
}

// countUntrackedCriticalNotification returns the number of unacknowledged
// NULL-booking critical_payment_log notifications for a dispute's deterministic
// id (disputeNotificationID).
func countUntrackedCriticalNotification(t *testing.T, disputeID string) int {
	t.Helper()
	var n int
	if err := db.Conn.QueryRow(context.Background(), `
		SELECT COUNT(*) FROM admin_notifications
		WHERE id = $1 AND reason = 'critical_payment_log'
		  AND booking_id IS NULL AND acknowledged_at IS NULL
	`, disputeNotificationID(disputeID)).Scan(&n); err != nil {
		t.Fatalf("failed to count critical notifications for dispute %s: %v", disputeID, err)
	}
	return n
}

// =============================================================================
// (a) handleDisputeStateUpdated — findPaymentByDisputeID fallback
// =============================================================================

// TestWebhook_DisputeStateUpdated_Lost_EmptyPaymentID_FallsBackToDisputeRow
// covers the findPaymentByDisputeID fallback: a dispute.state.updated event
// whose disputed_payment.payment_id is empty cannot resolve the payment via
// square_payment_id, so the handler recovers it from the seeded disputes row.
// A LOST state must still mark the payment failed and raise a CRITICAL
// notification — the fallback must not silently drop the chargeback.
func TestWebhook_DisputeStateUpdated_Lost_EmptyPaymentID_FallsBackToDisputeRow(t *testing.T) {
	payID, bookingID := createWebhookTestBookingPayment(t)
	if _, err := db.Conn.Exec(context.Background(), `
		INSERT INTO disputes (square_dispute_id, payment_id, status, amount, reason)
		VALUES ('dts_fallback_1', $1, 'open', 12.34, 'NO_KNOWLEDGE')
	`, payID); err != nil {
		t.Fatalf("failed to seed dispute row: %v", err)
	}

	event := SquareWebhookEvent{
		Type:      "dispute.state.updated",
		EventID:   "evt_dispute_fallback_1",
		CreatedAt: nowInRFC3339(0),
		Data: json.RawMessage(`{
			"type": "dispute",
			"id": "dts_fallback_1",
			"object": {
				"dispute": {
					"id": "dts_fallback_1",
					"state": "LOST",
					"amount_money": {"amount": 1234, "currency": "GBP"},
					"reason": "NO_KNOWLEDGE",
					"disputed_payment": {"payment_id": ""}
				}
			}
		}`),
	}
	w := deliverWebhook(t, event)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	if got := getDisputeStatus(t, "dts_fallback_1"); got != "lost" {
		t.Errorf("expected dispute status 'lost', got %q", got)
	}
	if got := getPaymentStatus(t, payID); got != "failed" {
		t.Errorf("expected payment 'failed' after lost dispute recovered via dispute row, got %q", got)
	}
	// The lost dispute is a CRITICAL money event — the admin notification
	// centre must surface it for the payment's booking.
	if n := countUnackedCriticalNotificationsForBooking(t, bookingID); n != 1 {
		t.Errorf("expected 1 unacknowledged critical_payment_log notification for booking %s, got %d", bookingID, n)
	}
	if n := countWebhookEvents(t, event.EventID); n != 1 {
		t.Errorf("expected 1 dedup row, got %d", n)
	}
}

// TestWebhook_DisputeStateUpdated_EmptyPaymentID_NoDisputeRow_RaisesCritical
// covers the fallback's dead end: when neither the payload's (empty) Square
// payment id nor the disputes table yields a payment, the chargeback is
// UNTRACKED — the handler raises the same critical_payment_log notification as
// dispute.created (booking_id NULL, the deterministic disputeNotificationID) so
// a state.updated arriving without a prior created event is never a silent
// money-loss path. No disputes row is written, the payment row is untouched,
// and the dedup row still commits (Square's retry is acknowledged 200, not
// re-dispatched forever).
func TestWebhook_DisputeStateUpdated_EmptyPaymentID_NoDisputeRow_RaisesCritical(t *testing.T) {
	payID, _ := createWebhookTestBookingPayment(t)

	event := SquareWebhookEvent{
		Type:      "dispute.state.updated",
		EventID:   "evt_dispute_no_row_1",
		CreatedAt: nowInRFC3339(0),
		Data: json.RawMessage(`{
			"type": "dispute",
			"id": "dts_no_dispute_row_1",
			"object": {
				"dispute": {
					"id": "dts_no_dispute_row_1",
					"state": "LOST",
					"amount_money": {"amount": 1234, "currency": "GBP"},
					"reason": "NO_KNOWLEDGE",
					"disputed_payment": {"payment_id": ""}
				}
			}
		}`),
	}
	w := deliverWebhook(t, event)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	var n int
	if err := db.Conn.QueryRow(context.Background(),
		"SELECT COUNT(*) FROM disputes WHERE square_dispute_id = 'dts_no_dispute_row_1'").Scan(&n); err != nil {
		t.Fatalf("failed to count disputes: %v", err)
	}
	if n != 0 {
		t.Errorf("expected no disputes row when the fallback finds no payment, got %d", n)
	}
	if got := getPaymentStatus(t, payID); got != "completed" {
		t.Errorf("expected payment untouched ('completed') when the fallback finds no dispute, got %q", got)
	}
	// The untracked chargeback MUST still surface in-app: exactly one
	// unacknowledged NULL-booking critical notification under the dispute's
	// deterministic id — the same contract as dispute.created's untracked
	// branch.
	if got := countUntrackedCriticalNotification(t, "dts_no_dispute_row_1"); got != 1 {
		t.Errorf("expected 1 unacknowledged NULL-booking critical notification for the untracked dispute, got %d", got)
	}
	if n := countWebhookEvents(t, event.EventID); n != 1 {
		t.Errorf("expected 1 dedup row (the no-op dispatch still commits), got %d", n)
	}
}

// =============================================================================
// (b) clawbackOneTillSale — non-gift-card branch
// =============================================================================

// TestWebhook_PaymentUpdated_Failed_NonGiftCardSale_MarksFailedNoClawback
// covers the non-gift-card branch of clawbackOneTillSale: a retail_product
// till sale (item_type != "gift_card") funded by a definitively-failed Square
// charge is marked failed WITHOUT reversing any gift-card funding — even when
// the sale's item_id happens to reference a real, funded gift card (the LEFT
// JOIN would find it; the item_type guard must short-circuit before any
// reversal).
func TestWebhook_PaymentUpdated_Failed_NonGiftCardSale_MarksFailedNoClawback(t *testing.T) {
	const squarePaymentID = "sqp_clawback_retail"
	giftCardID := createWebhookTestGiftCard(t, 60.00)
	saleID := createWebhookTestTillSale(t, squarePaymentID, "retail_product", giftCardID)

	w := deliverPaymentUpdatedFailed(t, squarePaymentID)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	if got := getTillSaleStatus(t, saleID); got != "failed" {
		t.Errorf("expected till sale 'failed', got %q", got)
	}
	// No gift-card balance was reversed: the card referenced by the sale's
	// item_id keeps its full £60.00 funding.
	total, remaining := getGiftCardFunding(t, giftCardID)
	if total != 60.00 || remaining != 60.00 {
		t.Errorf("expected gift card funding untouched (no clawback for a non-gift-card sale), got total=%v remaining=%v", total, remaining)
	}
}

// TestWebhook_PaymentUpdated_Failed_GiftCardSaleMissingCard_MarksFailedNoClawback
// covers the nil-isCreate variant of the same branch: a gift_card till sale
// whose item_id points at NO gift card (dangling id) makes the LEFT JOIN yield
// a NULL is_create — the branch must still mark the sale failed without
// attempting any reversal.
func TestWebhook_PaymentUpdated_Failed_GiftCardSaleMissingCard_MarksFailedNoClawback(t *testing.T) {
	const squarePaymentID = "sqp_clawback_dangling"
	saleID := createWebhookTestTillSale(t, squarePaymentID, "gift_card", "GCMISSING001")

	w := deliverPaymentUpdatedFailed(t, squarePaymentID)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	if got := getTillSaleStatus(t, saleID); got != "failed" {
		t.Errorf("expected till sale 'failed', got %q", got)
	}
	// The missing card means there is nothing to claw back — and the handler
	// must not error out: the webhook acknowledges 200 with a dedup row.
	if n := countWebhookEvents(t, "evt_"+squarePaymentID); n != 1 {
		t.Errorf("expected 1 dedup row, got %d", n)
	}
}

// =============================================================================
// (c) handleDisputeEvidence / handleTerminalCheckout — informational dispatch
// =============================================================================

// TestWebhook_DisputeEvidence_InformationalOnly covers both
// dispute.evidence.created and dispute.evidence.deleted: the handler logs and
// acknowledges 200 without writing a disputes row or raising any notification.
func TestWebhook_DisputeEvidence_InformationalOnly(t *testing.T) {
	cases := []struct {
		eventType string
		disputeID string
		eventID   string
	}{
		{"dispute.evidence.created", "dts_evidence_created_1", "evt_evidence_created_1"},
		{"dispute.evidence.deleted", "dts_evidence_deleted_1", "evt_evidence_deleted_1"},
	}
	for _, tc := range cases {
		event := SquareWebhookEvent{
			Type:      tc.eventType,
			EventID:   tc.eventID,
			CreatedAt: nowInRFC3339(0),
			Data: json.RawMessage(`{
				"type": "dispute",
				"id": "` + tc.disputeID + `",
				"object": {
					"dispute": {
						"id": "` + tc.disputeID + `",
						"state": "EVIDENCE_REQUIRED"
					}
				}
			}`),
		}
		w := deliverWebhook(t, event)
		if w.Code != http.StatusOK {
			t.Fatalf("expected 200 for %s, got %d: %s", tc.eventType, w.Code, w.Body.String())
		}
		// No state mutation: no disputes row is written for an evidence event.
		var n int
		if err := db.Conn.QueryRow(context.Background(),
			"SELECT COUNT(*) FROM disputes WHERE square_dispute_id = $1", tc.disputeID).Scan(&n); err != nil {
			t.Fatalf("failed to count disputes: %v", err)
		}
		if n != 0 {
			t.Errorf("expected no disputes row from %s, got %d", tc.eventType, n)
		}
		if got := countWebhookEvents(t, tc.eventID); got != 1 {
			t.Errorf("expected 1 dedup row for %s, got %d", tc.eventID, got)
		}
	}

	// The handler logs the evidence event (informational only).
	var buf bytes.Buffer
	oldOutput := log.Writer()
	log.SetOutput(&buf)
	defer log.SetOutput(oldOutput)
	event := SquareWebhookEvent{
		Type:      "dispute.evidence.created",
		EventID:   "evt_evidence_log_1",
		CreatedAt: nowInRFC3339(0),
		Data: json.RawMessage(`{
			"type": "dispute",
			"id": "dts_evidence_log_1",
			"object": {"dispute": {"id": "dts_evidence_log_1", "state": "UNDER_REVIEW"}}
		}`),
	}
	if w := deliverWebhook(t, event); w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	if out := buf.String(); !strings.Contains(out, "dispute evidence event for dispute") {
		t.Errorf("expected an informational evidence log line, got:\n%s", out)
	}
}

// TestWebhook_TerminalCheckout_InformationalOnly covers both
// terminal.checkout.created and terminal.checkout.updated: the handler logs
// and acknowledges 200 without writing any terminal_checkouts row.
func TestWebhook_TerminalCheckout_InformationalOnly(t *testing.T) {
	cases := []struct {
		eventType  string
		checkoutID string
		eventID    string
	}{
		{"terminal.checkout.created", "chk_round7_created_1", "evt_terminal_created_1"},
		{"terminal.checkout.updated", "chk_round7_updated_1", "evt_terminal_updated_1"},
	}
	for _, tc := range cases {
		event := SquareWebhookEvent{
			Type:      tc.eventType,
			EventID:   tc.eventID,
			CreatedAt: nowInRFC3339(0),
			Data:      json.RawMessage(`{"type": "terminal.checkout", "id": "` + tc.checkoutID + `"}`),
		}
		w := deliverWebhook(t, event)
		if w.Code != http.StatusOK {
			t.Fatalf("expected 200 for %s, got %d: %s", tc.eventType, w.Code, w.Body.String())
		}
		// No state mutation: no terminal_checkouts row is written.
		var n int
		if err := db.Conn.QueryRow(context.Background(),
			"SELECT COUNT(*) FROM terminal_checkouts WHERE checkout_id = $1", tc.checkoutID).Scan(&n); err != nil {
			t.Fatalf("failed to count terminal checkouts: %v", err)
		}
		if n != 0 {
			t.Errorf("expected no terminal_checkouts row from %s, got %d", tc.eventType, n)
		}
		if got := countWebhookEvents(t, tc.eventID); got != 1 {
			t.Errorf("expected 1 dedup row for %s, got %d", tc.eventID, got)
		}
	}

	var buf bytes.Buffer
	oldOutput := log.Writer()
	log.SetOutput(&buf)
	defer log.SetOutput(oldOutput)
	event := SquareWebhookEvent{
		Type:      "terminal.checkout.updated",
		EventID:   "evt_terminal_log_1",
		CreatedAt: nowInRFC3339(0),
		Data:      json.RawMessage(`{"type": "terminal.checkout", "id": "chk_round7_log_1"}`),
	}
	if w := deliverWebhook(t, event); w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	if out := buf.String(); !strings.Contains(out, "terminal.checkout event received") {
		t.Errorf("expected an informational terminal.checkout log line, got:\n%s", out)
	}
}