// <copyright file="ConflictResolution.cs" company="StellaOps">
// Copyright (c) StellaOps. Licensed under AGPL-3.0-or-later.
// </copyright>

namespace StellaOps.AirGap.Sync.Models;

/// <summary>
/// Result of conflict resolution for a job ID.
/// </summary>
public sealed record ConflictResolution
{
    /// <summary>
    /// Gets the type of conflict detected.
    /// </summary>
    public required ConflictType Type { get; init; }

    /// <summary>
    /// Gets the resolution strategy applied.
    /// </summary>
    public required ResolutionStrategy Resolution { get; init; }

    /// <summary>
    /// Gets the selected entry (when resolution is not Error).
    /// </summary>
    public OfflineJobLogEntry? SelectedEntry { get; init; }

    /// <summary>
    /// Gets the entries that were dropped.
    /// </summary>
    public IReadOnlyList<OfflineJobLogEntry>? DroppedEntries { get; init; }

    /// <summary>
    /// Gets the error message (when resolution is Error).
    /// </summary>
    public string? Error { get; init; }
}

/// <summary>
/// Types of conflicts that can occur during merge.
/// </summary>
public enum ConflictType
{
    /// <summary>
    /// Same JobId with different HLC timestamps but identical payload.
    /// </summary>
    DuplicateTimestamp,

    /// <summary>
    /// Same JobId with different payloads - indicates a bug.
    /// </summary>
    PayloadMismatch
}

/// <summary>
/// Strategies for resolving conflicts.
/// </summary>
public enum ResolutionStrategy
{
    /// <summary>
    /// Take the entry with the earliest HLC timestamp.
    /// </summary>
    TakeEarliest,

    /// <summary>
    /// Fail the merge - conflict cannot be resolved.
    /// </summary>
    Error
}