using System.Collections.Generic;
using ProjectM.Simulation;
using Unity.Entities;
using Unity.NetCode;
using UnityEngine;

namespace ProjectM.Client
{
    /// <summary>
    /// Client-side prep-loadout sender: a static enqueue (the Staging PREP panel buttons) drained into
    /// <see cref="PrepPurchaseRequest"/> RPCs (the MetaSpendSendSystem idiom). Carries only the option id; the server
    /// prices + re-validates (Staging, affordability, once-per-run). Statics reset on play-enter.
    /// </summary>
    [WorldSystemFilter(WorldSystemFilterFlags.ClientSimulation)]
    public partial class PrepPurchaseSendSystem : SystemBase
    {
        static readonly Queue<byte> s_Queue = new();

        [RuntimeInitializeOnLoadMethod(RuntimeInitializeLoadType.SubsystemRegistration)]
        static void ResetStatics() => s_Queue.Clear();

        /// <summary>Queue a prep-loadout purchase by catalog option id. The Staging PREP rows drive this.</summary>
        public static void RequestPrep(byte optionId) => s_Queue.Enqueue(optionId);

        protected override void OnCreate() => RequireForUpdate<NetworkId>();

        protected override void OnUpdate()
        {
            while (s_Queue.Count > 0)
            {
                var req = EntityManager.CreateEntity(typeof(PrepPurchaseRequest), typeof(SendRpcCommandRequest));
                EntityManager.SetComponentData(req, new PrepPurchaseRequest { OptionId = s_Queue.Dequeue() });
            }
        }
    }
}