using System.Collections.Concurrent;
using MAF1.Decisions;
using MAF1.Plugins;

namespace MAF1.Web;

/// <summary>
/// 一次可暂停的运行。NextIndex 记住停在第几个节点；Pending 是当前确认请求。
/// Mutex 防止「用户点击」和「超时自动确认」同时 Continue。
/// </summary>
internal sealed class WorkflowSession
{
    public required string RunId { get; init; }
    public required WorkflowGraph Graph { get; init; }
    public required NodeCatalogSnapshot Catalog { get; init; }
    public required List<string> Order { get; init; }
    public required Dictionary<string, Dictionary<string, object?>> Outputs { get; init; }
    public required List<NodeRunLog> Steps { get; init; }
    public int NextIndex { get; set; }
    public DecisionRequest? Pending { get; set; }
    public bool Completed { get; set; }
    public WorkflowRunResult LastResult { get; set; } = new();
    public DecisionAnswer? AppliedDecision { get; set; }
    public CancellationTokenSource TimeoutCts { get; set; } = new();
    public SemaphoreSlim Mutex { get; } = new(1, 1);
    public object Sync { get; } = new();
}

/// <summary>进程内运行字典。服务重启后 runId 会失效，学习项目不做持久化。</summary>
public sealed class WorkflowRunStore
{
    private readonly ConcurrentDictionary<string, WorkflowSession> _sessions = new(StringComparer.OrdinalIgnoreCase);

    internal bool TryAdd(WorkflowSession session) => _sessions.TryAdd(session.RunId, session);

    internal bool TryGet(string runId, out WorkflowSession? session) => _sessions.TryGetValue(runId, out session);

    public WorkflowRunResult? GetResult(string runId)
        => _sessions.TryGetValue(runId, out WorkflowSession? session) ? session.LastResult : null;
}