using System.Threading;
using System.Threading.Tasks;
using GB5Shared.DTO.Framework.Login;
using GB5Shared.DTO.GOP;
using Microsoft.Extensions.Logging;

namespace FrameworkBLL.GOP.Worker.NodeExecutors
{
    // ============================================================
    // ApprovalNodeExecutor — executes an Approval node type.
    //
    // GopExecutionPipeline intercepts "Approval" steps BEFORE dispatching to any
    // INodeExecutor — it pauses the execution (Status='PendingApproval') and returns,
    // rather than calling ExecuteAsync here. This executor exists only so the
    // keyed-DI pattern stays complete/extensible (e.g. a future design-time
    // "test execute" path that runs the graph without pause semantics) — it is a
    // pass-through that never blocks.
    // ============================================================
    public class ApprovalNodeExecutor : INodeExecutor
    {
        private readonly ILogger<ApprovalNodeExecutor> _Logger;

        public ApprovalNodeExecutor(ILogger<ApprovalNodeExecutor> logger) => _Logger = logger;

        public string NodeType => "Approval";

        public Task<string?> ExecuteAsync(
            GopFlowSnapshotStepDTO step,
            GopExecutionHeaderDTO  header,
            string?                inputPayloadJson,
            LoginDTO               loginDTO,
            CancellationToken      ct)
        {
            _Logger.LogDebug(
                "ApprovalNodeExecutor: execution {ExecutionId} step {NodeCode} — pass-through (pipeline handles gating)",
                header.ExecutionId, step.NodeCode);

            return Task.FromResult(inputPayloadJson);
        }
    }
}