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

using StellaOps.HybridLogicalClock;

namespace StellaOps.AirGap.Sync.Models;

/// <summary>
/// Result of merging job logs from multiple offline nodes.
/// </summary>
public sealed record MergeResult
{
    /// <summary>
    /// Gets the merged entries in HLC total order.
    /// </summary>
    public required IReadOnlyList<MergedJobEntry> MergedEntries { get; init; }

    /// <summary>
    /// Gets duplicate entries that were dropped during merge.
    /// </summary>
    public required IReadOnlyList<DuplicateEntry> Duplicates { get; init; }

    /// <summary>
    /// Gets the merged chain head (final link after merge).
    /// </summary>
    public byte[]? MergedChainHead { get; init; }

    /// <summary>
    /// Gets the source node IDs that contributed to this merge.
    /// </summary>
    public required IReadOnlyList<string> SourceNodes { get; init; }
}

/// <summary>
/// A job entry after merge with unified chain link.
/// </summary>
public sealed class MergedJobEntry
{
    /// <summary>
    /// Gets or sets the source node ID that created this entry.
    /// </summary>
    public required string SourceNodeId { get; set; }

    /// <summary>
    /// Gets or sets the HLC timestamp.
    /// </summary>
    public required HlcTimestamp THlc { get; set; }

    /// <summary>
    /// Gets or sets the job ID.
    /// </summary>
    public required Guid JobId { get; set; }

    /// <summary>
    /// Gets or sets the partition key.
    /// </summary>
    public string? PartitionKey { get; set; }

    /// <summary>
    /// Gets or sets the serialized payload.
    /// </summary>
    public required string Payload { get; set; }

    /// <summary>
    /// Gets or sets the payload hash.
    /// </summary>
    public required byte[] PayloadHash { get; set; }

    /// <summary>
    /// Gets or sets the original chain link from the source node.
    /// </summary>
    public required byte[] OriginalLink { get; set; }

    /// <summary>
    /// Gets or sets the merged chain link (computed during merge).
    /// </summary>
    public byte[]? MergedLink { get; set; }
}

/// <summary>
/// Represents a duplicate entry dropped during merge.
/// </summary>
public sealed record DuplicateEntry(
    Guid JobId,
    string NodeId,
    HlcTimestamp THlc);