using System.Text;
using System.Text.Json;
using Microsoft.Extensions.Options;
using RabbitMQ.Client;

public interface IReconciliationPublisher
{
    Task PublishAsync(ReconciliationAlert alert, CancellationToken ct);
}

public sealed class ReconciliationPublisher : IReconciliationPublisher
{
    private readonly RabbitMqOptions _opts;
    private readonly ILogger<ReconciliationPublisher> _logger;

    public ReconciliationPublisher(
        IOptions<RabbitMqOptions> opts,
        ILogger<ReconciliationPublisher> logger)
    {
        _opts = opts.Value;
        _logger = logger;
    }

    public Task PublishAsync(ReconciliationAlert alert, CancellationToken ct)
    {
        var factory = new ConnectionFactory
        {
            HostName = _opts.Host,
            Port = _opts.Port,
            UserName = _opts.Username,
            Password = _opts.Password,
        };

        using var connection = factory.CreateConnection("reconciliation-publisher");
        using var channel = connection.CreateModel();

        var props = channel.CreateBasicProperties();
        props.Persistent = true;

        var payload = JsonSerializer.Serialize(new
        {
            reconciliationAlertId = alert.Id,
            checkType = alert.CheckType.ToDbString(),
            encounterId = alert.EncounterId,
            patientId = alert.PatientId,
            details = alert.Details,
            createdAt = alert.CreatedAt,
        });

        channel.BasicPublish(
            exchange: RabbitMqTopologyProvisioner.Exchange,
            routingKey: RabbitMqTopologyProvisioner.ReconciliationKey,
            basicProperties: props,
            body: Encoding.UTF8.GetBytes(payload));

        _logger.LogInformation(
            "[RECONCILIATION-PUBLISHED] CheckType={CheckType} EncounterId={EncounterId}",
            alert.CheckType.ToDbString(), alert.EncounterId);

        return Task.CompletedTask;
    }
}