using System;
using System.Collections.Generic;

namespace Svrnty.CQRS.Sagas.Abstractions;

/// <summary>
/// Represents the persistent state of a saga instance.
/// </summary>
public class SagaState
{
    /// <summary>
    /// Unique identifier for this saga instance.
    /// </summary>
    public Guid SagaId { get; set; } = Guid.NewGuid();

    /// <summary>
    /// The fully qualified type name of the saga.
    /// </summary>
    public string SagaType { get; set; } = string.Empty;

    /// <summary>
    /// Correlation ID for tracing across services.
    /// </summary>
    public Guid CorrelationId { get; set; }

    /// <summary>
    /// Current execution status.
    /// </summary>
    public SagaStatus Status { get; set; } = SagaStatus.NotStarted;

    /// <summary>
    /// Index of the current step being executed.
    /// </summary>
    public int CurrentStepIndex { get; set; }

    /// <summary>
    /// Name of the current step being executed.
    /// </summary>
    public string? CurrentStepName { get; set; }

    /// <summary>
    /// Results from completed steps, keyed by step name.
    /// </summary>
    public Dictionary<string, object?> StepResults { get; set; } = new();

    /// <summary>
    /// Names of steps that have been completed.
    /// </summary>
    public List<string> CompletedSteps { get; set; } = new();

    /// <summary>
    /// Errors that occurred during saga execution.
    /// </summary>
    public List<SagaStepError> Errors { get; set; } = new();

    /// <summary>
    /// Serialized saga data (JSON).
    /// </summary>
    public string? SerializedData { get; set; }

    /// <summary>
    /// When the saga was created.
    /// </summary>
    public DateTimeOffset CreatedAt { get; set; } = DateTimeOffset.UtcNow;

    /// <summary>
    /// When the saga was last updated.
    /// </summary>
    public DateTimeOffset? UpdatedAt { get; set; }

    /// <summary>
    /// When the saga completed (successfully or compensated).
    /// </summary>
    public DateTimeOffset? CompletedAt { get; set; }
}

/// <summary>
/// Represents an error that occurred during saga step execution.
/// </summary>
public record SagaStepError(
    string StepName,
    string ErrorMessage,
    string? StackTrace,
    DateTimeOffset OccurredAt
);