using GB5Shared.DTO.Framework.Login;
using GB5Shared.QueueReader;
using GB5Shared.Telemetry;
using MMDAL.DTO.Scheduling;
using Microsoft.Extensions.Logging;
using System.Text.Json;

namespace MMSL.Services.Handlers;

// Processes a SCHEDULINGRUN queue message by running the full scheduling engine pipeline.
// Payload must be a JSON-serialized SchedulingRunTriggerDTO.
public sealed class SchedulingRunQueueHandler : IJobQueueHandler
{
    public string MessageType => "SCHEDULINGRUN";

    private readonly SchedulingRunProcessingService        _processor;
    private readonly ILogger<SchedulingRunQueueHandler>    _logger;

    public SchedulingRunQueueHandler(SchedulingRunProcessingService processor, ILogger<SchedulingRunQueueHandler> logger)
    {
        _processor = processor;
        _logger    = logger;
    }

    public async Task HandleAsync(string payload, LoginDTO login, long queueId, CancellationToken ct)
    {
        GB5Trace.Step("schedulingrun-queue-process", new { TenantId = login.ClientId });

        SchedulingRunTriggerDTO? trigger;
        try
        {
            trigger = JsonSerializer.Deserialize<SchedulingRunTriggerDTO>(payload,
                new JsonSerializerOptions { PropertyNameCaseInsensitive = true });
        }
        catch (Exception ex)
        {
            _logger.LogError(ex, "SchedulingRunQueueHandler: failed to deserialize payload | TenantId={TenantId}", login.ClientId);
            throw;
        }

        if (trigger is null)
            throw new InvalidOperationException("SchedulingRunQueueHandler: payload deserialized to null");

        _logger.LogInformation(
            "SchedulingRunQueueHandler: starting scheduling run WorkOUId={WorkOUId} for tenant {TenantId}",
            trigger.WorkOUId, login.ClientId);

        await _processor.ProcessAsyncWithLogin(trigger, login, ct).ConfigureAwait(false);
    }
}