package health

import (
	"context"
	"errors"
	"testing"

	"gl/domain/ledger"
)

type databaseStub struct{ err error }

func (s databaseStub) Ping(context.Context) error { return s.err }

type settlementStub struct {
	stats ledger.SettlementStats
	err   error
}

func (s settlementStub) Stats(context.Context) (ledger.SettlementStats, error) {
	return s.stats, s.err
}

func TestCheckReportsDatabaseReadiness(t *testing.T) {
	for _, tc := range []struct {
		name  string
		db    Database
		ready bool
	}{
		{name: "not connected", db: nil, ready: false},
		{name: "ready", db: databaseStub{}, ready: true},
		{name: "unavailable", db: databaseStub{err: errors.New("down")}, ready: false},
	} {
		t.Run(tc.name, func(t *testing.T) {
			got := NewService(tc.db).Check(context.Background())
			if got.Serving != tc.ready || got.DatabaseReady != tc.ready {
				t.Fatalf("unexpected status: %+v", got)
			}
		})
	}
}

func TestCheckReportsSettlementBacklog(t *testing.T) {
	monitor := settlementStub{stats: ledger.SettlementStats{Pending: 2, Retryable: 3, OldestPendingSeconds: 60}}
	got := NewService(databaseStub{}, monitor).Check(context.Background())
	if !got.Serving || !got.DatabaseReady || !got.SettlementEnabled || !got.SettlementReady || got.SettlementStats != monitor.stats {
		t.Fatalf("unexpected status: %+v", got)
	}
}

func TestCheckExposesManualReviewWithoutStoppingSettlementQueue(t *testing.T) {
	got := NewService(databaseStub{}, settlementStub{stats: ledger.SettlementStats{ManualReview: 1}}).Check(context.Background())
	if !got.Serving || !got.SettlementReady || got.SettlementStats.ManualReview != 1 {
		t.Fatalf("unexpected status: %+v", got)
	}
}

func TestCheckReportsSettlementQueryFailure(t *testing.T) {
	got := NewService(databaseStub{}, settlementStub{err: errors.New("query failed")}).Check(context.Background())
	if !got.Serving || got.SettlementReady {
		t.Fatalf("unexpected status: %+v", got)
	}
}