//go:build test

package webhooks

import (
	"context"
	"encoding/json"
	"net/http"
	"net/http/httptest"
	"strings"
	"testing"

	"crussell/db"
)

// =============================================================================
// Helpers — DB-backed state assertions
// =============================================================================

// createWebhookTestPayment inserts a payment row with the given Square charge
// id and returns the local payment id. The test DB is fresh per package run,
// so no cleanup is needed.
func createWebhookTestPayment(t *testing.T, squarePaymentID, status string) string {
	t.Helper()
	var id string
	err := db.Conn.QueryRow(context.Background(), `
		INSERT INTO payments (payment_type, payment_method, status, amount, square_payment_id, created_at, updated_at)
		VALUES ('full', 'online_square', $2, 10.00, $1, NOW(), NOW())
		RETURNING id
	`, squarePaymentID, status).Scan(&id)
	if err != nil {
		t.Fatalf("failed to create webhook test payment: %v", err)
	}
	return id
}

func createWebhookTestRefund(t *testing.T, paymentID, squareRefundID, status string) string {
	t.Helper()
	var id string
	err := db.Conn.QueryRow(context.Background(), `
		INSERT INTO refunds (payment_id, amount, reason, status, square_refund_id, created_at)
		VALUES ($1, 5.00, 'webhook test refund', $3, $2, NOW())
		RETURNING id
	`, paymentID, squareRefundID, status).Scan(&id)
	if err != nil {
		t.Fatalf("failed to create webhook test refund: %v", err)
	}
	return id
}

func getPaymentStatus(t *testing.T, id string) string {
	t.Helper()
	var status string
	if err := db.Conn.QueryRow(context.Background(),
		"SELECT status FROM payments WHERE id = $1", id).Scan(&status); err != nil {
		t.Fatalf("failed to read payment status: %v", err)
	}
	return status
}

func getRefundStatus(t *testing.T, id string) string {
	t.Helper()
	var status string
	if err := db.Conn.QueryRow(context.Background(),
		"SELECT status FROM refunds WHERE id = $1", id).Scan(&status); err != nil {
		t.Fatalf("failed to read refund status: %v", err)
	}
	return status
}

func getDisputeStatus(t *testing.T, squareDisputeID string) string {
	t.Helper()
	var status string
	if err := db.Conn.QueryRow(context.Background(),
		"SELECT status FROM disputes WHERE square_dispute_id = $1", squareDisputeID).Scan(&status); err != nil {
		t.Fatalf("failed to read dispute status: %v", err)
	}
	return status
}

func countCriticalNotifications(t *testing.T) int {
	t.Helper()
	var n int
	if err := db.Conn.QueryRow(context.Background(),
		"SELECT COUNT(*) FROM admin_notifications WHERE reason = 'critical_payment_log'").Scan(&n); err != nil {
		t.Fatalf("failed to count critical_payment_log notifications: %v", err)
	}
	return n
}

// deliverWebhook signs and dispatches a Square event through the full handler.
func deliverWebhook(t *testing.T, event SquareWebhookEvent) *httptest.ResponseRecorder {
	t.Helper()
	body, err := json.Marshal(event)
	if err != nil {
		t.Fatalf("failed to marshal webhook event: %v", err)
	}
	sig := webhookTestEnv(t, body)
	return makeWebhookRequest(body, sig, context.Background())
}

// =============================================================================
// Dispute handling — dispute.created
// =============================================================================

func TestWebhook_DisputeCreated_InsertsDisputeRow(t *testing.T) {
	const squarePaymentID = "sqp_dispute_created"
	payID := createWebhookTestPayment(t, squarePaymentID, "completed")

	event := SquareWebhookEvent{
		Type:      "dispute.created",
		EventID:   "evt_dispute_created_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "dispute",
			"id": "dts_dispute_created_1",
			"object": {
				"dispute": {
					"id": "dts_dispute_created_1",
					"state": "UNDER_REVIEW",
					"amount_money": {"amount": 1234, "currency": "GBP"},
					"reason": "NO_KNOWLEDGE",
					"disputed_payment": {"payment_id": "` + squarePaymentID + `"}
				}
			}
		}`),
	}
	w := deliverWebhook(t, event)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}

	var (
		status string
		amount float64
		reason string
		pid    string
	)
	err := db.Conn.QueryRow(context.Background(), `
		SELECT status, amount, reason, payment_id FROM disputes WHERE square_dispute_id = 'dts_dispute_created_1'
	`).Scan(&status, &amount, &reason, &pid)
	if err != nil {
		t.Fatalf("expected a disputes row to be inserted, got: %v", err)
	}
	if status != "open" {
		t.Errorf("expected dispute status 'open', got %q", status)
	}
	if amount != 12.34 {
		t.Errorf("expected dispute amount 12.34, got %v", amount)
	}
	if reason != "NO_KNOWLEDGE" {
		t.Errorf("expected dispute reason 'NO_KNOWLEDGE', got %q", reason)
	}
	if pid != payID {
		t.Errorf("expected dispute payment_id %s, got %s", payID, pid)
	}

	// A dispute is a CRITICAL money event — the admin notification centre must
	// surface it.
	if got := countCriticalNotifications(t); got < 1 {
		t.Errorf("expected at least 1 critical_payment_log admin notification, got %d", got)
	}
}

func TestWebhook_DisputeCreated_NoLocalPayment_NoRow(t *testing.T) {
	event := SquareWebhookEvent{
		Type:      "dispute.created",
		EventID:   "evt_dispute_orphan_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "dispute",
			"id": "dts_orphan_1",
			"object": {
				"dispute": {
					"id": "dts_orphan_1",
					"state": "UNDER_REVIEW",
					"amount_money": {"amount": 1000, "currency": "GBP"},
					"disputed_payment": {"payment_id": "sqp_never_seen"}
				}
			}
		}`),
	}
	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_orphan_1'").Scan(&n); err != nil {
		t.Fatalf("failed to count disputes: %v", err)
	}
	if n != 0 {
		t.Errorf("expected no disputes row for an unknown square payment, got %d", n)
	}
}

func TestWebhook_DisputeCreated_LongReason_Truncated(t *testing.T) {
	const squarePaymentID = "sqp_dispute_longreason"
	_ = createWebhookTestPayment(t, squarePaymentID, "completed")

	longReason := strings.Repeat("z", 300)
	event := SquareWebhookEvent{
		Type:      "dispute.created",
		EventID:   "evt_dispute_longreason_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "dispute",
			"id": "dts_longreason_1",
			"object": {
				"dispute": {
					"id": "dts_longreason_1",
					"state": "UNDER_REVIEW",
					"amount_money": {"amount": 1234, "currency": "GBP"},
					"reason": "` + longReason + `",
					"disputed_payment": {"payment_id": "` + squarePaymentID + `"}
				}
			}
		}`),
	}
	w := deliverWebhook(t, event)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}

	// disputes.reason is VARCHAR(192): the over-long reason must be truncated
	// so the INSERT succeeds instead of failing (and, after the dedup row
	// commits, silently dropping the dispute).
	var storedReason string
	if err := db.Conn.QueryRow(context.Background(),
		"SELECT reason FROM disputes WHERE square_dispute_id = 'dts_longreason_1'").Scan(&storedReason); err != nil {
		t.Fatalf("expected a disputes row to be inserted, got: %v", err)
	}
	if len(storedReason) > 192 {
		t.Errorf("expected reason truncated to <=192 chars, got %d", len(storedReason))
	}
	if storedReason != strings.Repeat("z", 192) {
		t.Errorf("expected reason truncated to exactly 192 'z' chars, got %q", storedReason)
	}
}

// =============================================================================
// Dispute handling — dispute.state.updated
// =============================================================================

func TestWebhook_DisputeStateUpdated_Lost_MarksPaymentFailed(t *testing.T) {
	const squarePaymentID = "sqp_dispute_lost"
	payID := createWebhookTestPayment(t, squarePaymentID, "completed")
	// Seed the dispute row as dispute.created would have.
	if _, err := db.Conn.Exec(context.Background(), `
		INSERT INTO disputes (square_dispute_id, payment_id, status, amount, reason)
		VALUES ('dts_lost_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_lost_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "dispute",
			"id": "dts_lost_1",
			"object": {
				"dispute": {
					"id": "dts_lost_1",
					"state": "LOST",
					"amount_money": {"amount": 1234, "currency": "GBP"},
					"reason": "NO_KNOWLEDGE",
					"disputed_payment": {"payment_id": "` + squarePaymentID + `"}
				}
			}
		}`),
	}
	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_lost_1"); got != "lost" {
		t.Errorf("expected dispute status 'lost', got %q", got)
	}
	if got := getPaymentStatus(t, payID); got != "failed" {
		t.Errorf("expected payment status 'failed' after lost dispute, got %q", got)
	}
	if got := countCriticalNotifications(t); got < 1 {
		t.Errorf("expected a critical_payment_log notification for the lost dispute, got %d", got)
	}
}

func TestWebhook_DisputeStateUpdated_Won_KeepsPaymentCompleted(t *testing.T) {
	const squarePaymentID = "sqp_dispute_won"
	payID := createWebhookTestPayment(t, squarePaymentID, "completed")

	// No seeded dispute row: state.updated arriving before dispute.created must
	// upsert the row.
	event := SquareWebhookEvent{
		Type:      "dispute.state.updated",
		EventID:   "evt_dispute_won_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "dispute",
			"id": "dts_won_1",
			"object": {
				"dispute": {
					"id": "dts_won_1",
					"state": "WON",
					"amount_money": {"amount": 1234, "currency": "GBP"},
					"disputed_payment": {"payment_id": "` + squarePaymentID + `"}
				}
			}
		}`),
	}
	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_won_1"); got != "won" {
		t.Errorf("expected dispute status 'won', got %q", got)
	}
	if got := getPaymentStatus(t, payID); got != "completed" {
		t.Errorf("expected payment to stay 'completed' after won dispute, got %q", got)
	}
}

func TestWebhook_DisputeStateUpdated_Open_KeepsOpen(t *testing.T) {
	const squarePaymentID = "sqp_dispute_open"
	payID := createWebhookTestPayment(t, squarePaymentID, "completed")
	if _, err := db.Conn.Exec(context.Background(), `
		INSERT INTO disputes (square_dispute_id, payment_id, status, amount, reason)
		VALUES ('dts_open_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_open_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "dispute",
			"id": "dts_open_1",
			"object": {
				"dispute": {
					"id": "dts_open_1",
					"state": "EVIDENCE_REQUIRED",
					"amount_money": {"amount": 1234, "currency": "GBP"},
					"disputed_payment": {"payment_id": "` + squarePaymentID + `"}
				}
			}
		}`),
	}
	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_open_1"); got != "open" {
		t.Errorf("expected dispute to stay 'open' on EVIDENCE_REQUIRED, got %q", got)
	}
	if got := getPaymentStatus(t, payID); got != "completed" {
		t.Errorf("expected payment to stay 'completed', got %q", got)
	}
}

// =============================================================================
// State mutation — payment.updated
// =============================================================================

func TestWebhook_PaymentUpdated_UpdatesPaymentStatus(t *testing.T) {
	const squarePaymentID = "sqp_updated_completed"
	payID := createWebhookTestPayment(t, squarePaymentID, "pending")

	event := SquareWebhookEvent{
		Type:      "payment.updated",
		EventID:   "evt_payment_updated_completed_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "payment",
			"id": "` + squarePaymentID + `",
			"object": {
				"payment": {
					"id": "` + squarePaymentID + `",
					"status": "COMPLETED"
				}
			}
		}`),
	}
	w := deliverWebhook(t, event)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	if got := getPaymentStatus(t, payID); got != "completed" {
		t.Errorf("expected payment status 'completed', got %q", got)
	}
}

func TestWebhook_PaymentUpdated_FailedStatus(t *testing.T) {
	const squarePaymentID = "sqp_updated_failed"
	payID := createWebhookTestPayment(t, squarePaymentID, "pending")

	event := SquareWebhookEvent{
		Type:      "payment.updated",
		EventID:   "evt_payment_updated_failed_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "payment",
			"id": "` + squarePaymentID + `",
			"object": {
				"payment": {
					"id": "` + squarePaymentID + `",
					"status": "FAILED"
				}
			}
		}`),
	}
	w := deliverWebhook(t, event)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	if got := getPaymentStatus(t, payID); got != "failed" {
		t.Errorf("expected payment status 'failed', got %q", got)
	}
}

func TestWebhook_PaymentUpdated_NonTerminal_LeavesPending(t *testing.T) {
	const squarePaymentID = "sqp_updated_approved"
	payID := createWebhookTestPayment(t, squarePaymentID, "pending")

	event := SquareWebhookEvent{
		Type:      "payment.updated",
		EventID:   "evt_payment_updated_approved_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "payment",
			"id": "` + squarePaymentID + `",
			"object": {
				"payment": {
					"id": "` + squarePaymentID + `",
					"status": "APPROVED"
				}
			}
		}`),
	}
	w := deliverWebhook(t, event)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	if got := getPaymentStatus(t, payID); got != "pending" {
		t.Errorf("expected payment to stay 'pending' on non-terminal APPROVED, got %q", got)
	}
}

// TestWebhook_PaymentUpdated_DoesNotRevertRefunded guards the pending-only
// transition: Square fires payment.updated for ANY field change (e.g. a fee
// recalculation on a fully refunded charge), and that must not flip the local
// row back from 'refunded' to 'completed' — which would reopen the
// over-refund guard.
func TestWebhook_PaymentUpdated_DoesNotRevertRefunded(t *testing.T) {
	const squarePaymentID = "sqp_updated_refunded"
	payID := createWebhookTestPayment(t, squarePaymentID, "refunded")

	event := SquareWebhookEvent{
		Type:      "payment.updated",
		EventID:   "evt_payment_updated_refunded_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "payment",
			"id": "` + squarePaymentID + `",
			"object": {
				"payment": {
					"id": "` + squarePaymentID + `",
					"status": "COMPLETED"
				}
			}
		}`),
	}
	w := deliverWebhook(t, event)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	if got := getPaymentStatus(t, payID); got != "refunded" {
		t.Errorf("expected refunded payment to stay 'refunded', got %q", got)
	}
}

func TestWebhook_PaymentUpdated_IdempotentReplay(t *testing.T) {
	const squarePaymentID = "sqp_updated_idem"
	payID := createWebhookTestPayment(t, squarePaymentID, "pending")

	event := SquareWebhookEvent{
		Type:      "payment.updated",
		EventID:   "evt_payment_updated_idem_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "payment",
			"id": "` + squarePaymentID + `",
			"object": {
				"payment": {
					"id": "` + squarePaymentID + `",
					"status": "COMPLETED"
				}
			}
		}`),
	}
	// Two deliveries of the SAME event_id: the second is dropped by dedup, the
	// state mutation applies exactly once.
	w1 := deliverWebhook(t, event)
	if w1.Code != http.StatusOK {
		t.Fatalf("expected first delivery 200, got %d: %s", w1.Code, w1.Body.String())
	}
	w2 := deliverWebhook(t, event)
	if w2.Code != http.StatusOK {
		t.Fatalf("expected replay 200, got %d: %s", w2.Code, w2.Body.String())
	}
	if got := getPaymentStatus(t, payID); got != "completed" {
		t.Errorf("expected payment status 'completed' after idempotent replay, got %q", got)
	}
	if n := countWebhookEvents(t, event.EventID); n != 1 {
		t.Errorf("expected exactly 1 dedup row after replay, got %d", n)
	}
}

// =============================================================================
// State mutation — refund.updated
// =============================================================================

func TestWebhook_RefundUpdated_UpdatesRefundStatus(t *testing.T) {
	const (
		squarePaymentID = "sqp_refund_pay"
		squareRefundID  = "sqr_updated_completed"
	)
	payID := createWebhookTestPayment(t, squarePaymentID, "completed")
	refundID := createWebhookTestRefund(t, payID, squareRefundID, "pending")

	event := SquareWebhookEvent{
		Type:      "refund.updated",
		EventID:   "evt_refund_updated_completed_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "refund",
			"id": "` + squareRefundID + `",
			"object": {
				"refund": {
					"id": "` + squareRefundID + `",
					"status": "COMPLETED",
					"payment_id": "` + squarePaymentID + `"
				}
			}
		}`),
	}
	w := deliverWebhook(t, event)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	if got := getRefundStatus(t, refundID); got != "completed" {
		t.Errorf("expected refund status 'completed', got %q", got)
	}
}

func TestWebhook_RefundUpdated_FailedStatus(t *testing.T) {
	const (
		squarePaymentID = "sqp_refund_pay_fail"
		squareRefundID  = "sqr_updated_failed"
	)
	payID := createWebhookTestPayment(t, squarePaymentID, "completed")
	refundID := createWebhookTestRefund(t, payID, squareRefundID, "pending")

	event := SquareWebhookEvent{
		Type:      "refund.updated",
		EventID:   "evt_refund_updated_failed_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "refund",
			"id": "` + squareRefundID + `",
			"object": {
				"refund": {
					"id": "` + squareRefundID + `",
					"status": "FAILED",
					"payment_id": "` + squarePaymentID + `"
				}
			}
		}`),
	}
	w := deliverWebhook(t, event)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	if got := getRefundStatus(t, refundID); got != "failed" {
		t.Errorf("expected refund status 'failed', got %q", got)
	}
}

func TestWebhook_RefundUpdated_NonTerminal_LeavesPending(t *testing.T) {
	const (
		squarePaymentID = "sqp_refund_pay_pending"
		squareRefundID  = "sqr_updated_pending"
	)
	payID := createWebhookTestPayment(t, squarePaymentID, "completed")
	refundID := createWebhookTestRefund(t, payID, squareRefundID, "pending")

	event := SquareWebhookEvent{
		Type:      "refund.updated",
		EventID:   "evt_refund_updated_pending_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "refund",
			"id": "` + squareRefundID + `",
			"object": {
				"refund": {
					"id": "` + squareRefundID + `",
					"status": "PENDING",
					"payment_id": "` + squarePaymentID + `"
				}
			}
		}`),
	}
	w := deliverWebhook(t, event)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	if got := getRefundStatus(t, refundID); got != "pending" {
		t.Errorf("expected refund to stay 'pending' on non-terminal PENDING, got %q", got)
	}
}

// TestWebhook_RefundUpdated_DoesNotDemoteCompleted guards the FAILED
// transition: a completed refund must never be demoted to 'failed' by a late
// webhook, since the over-refund guard counts 'completed' refunds — demoting
// would let the guard exclude money that already moved.
func TestWebhook_RefundUpdated_DoesNotDemoteCompleted(t *testing.T) {
	const (
		squarePaymentID = "sqp_refund_pay_demote"
		squareRefundID  = "sqr_demote"
	)
	payID := createWebhookTestPayment(t, squarePaymentID, "completed")
	refundID := createWebhookTestRefund(t, payID, squareRefundID, "completed")

	event := SquareWebhookEvent{
		Type:      "refund.updated",
		EventID:   "evt_refund_demote_1",
		CreatedAt: "2025-01-01T00:00:00Z",
		Data: json.RawMessage(`{
			"type": "refund",
			"id": "` + squareRefundID + `",
			"object": {
				"refund": {
					"id": "` + squareRefundID + `",
					"status": "FAILED",
					"payment_id": "` + squarePaymentID + `"
				}
			}
		}`),
	}
	w := deliverWebhook(t, event)
	if w.Code != http.StatusOK {
		t.Fatalf("expected 200, got %d: %s", w.Code, w.Body.String())
	}
	if got := getRefundStatus(t, refundID); got != "completed" {
		t.Errorf("expected completed refund to stay 'completed', got %q", got)
	}
}