using Unity.Entities;

namespace ProjectM.Simulation
{
    /// <summary>
    /// Server-world, UNMANAGED bridge holding a save slice the menu staged for a "Continue" session, applied
    /// AT SPAWN by the server CycleDirectorSpawnSystem so the director ghost is BORN correct — it never
    /// serializes an empty ledger to clients (no replication flicker). The menu creates exactly one of these
    /// (with the <see cref="PendingSaveLedgerRow"/> buffer) in the freshly created ServerWorld BEFORE the
    /// gameplay subscene streams in; the spawn system consumes + destroys it. Unmanaged so the Bursted spawn
    /// system reads it without a managed bridge.
    /// </summary>
    public struct PendingSave : IComponentData
    {
        /// <summary>v6: persisted run counters to restore into MetaCounters + the born-correct RunInfo HUD mirror.</summary>
        public int RunsCompleted;
        public int MaxDepthReached;

        /// <summary>0 = nothing staged (New Game); non-zero = apply the staged slice at director spawn.</summary>
        public byte HasData;
    }

    /// <summary>One staged ledger row for a Continue session; copied into the director's StorageEntry buffer at spawn.</summary>
    public struct PendingSaveLedgerRow : IBufferElementData
    {
        public ushort ItemId;
        public int Count;
    }

    /// <summary>One staged PERMANENT meta tier for a Continue session (v6) — copied VERBATIM into the director's
    /// replicated MetaTierState buffer at spawn (unknown ids preserved for round-trip; clamping happens only at
    /// seed/shop/spend). The buffer is added UNCONDITIONALLY at staging (empty OK) — the Bursted spawn system
    /// GetBuffers it inside the HasData block and a missing buffer would throw on any Continue.</summary>
    public struct PendingMetaRow : IBufferElementData
    {
        public byte ClassId;
        public byte UpgradeId;
        public byte Tier;
    }

    /// <summary>One staged player-built structure row for a Continue session; BaseRestoreSystem replays it
    /// charge-free into the freshly-streamed base. Mirrors <see cref="StructureSave"/> but as an unmanaged ECS
    /// buffer element (staged in the ServerWorld before the subscene streams).</summary>
    public struct PendingStructure : IBufferElementData
    {
        public byte Type;
        public int CellX;
        public int CellZ;
        public float HP; // EB-1: staged hit points (BaseRestoreSystem restores 0 -> baked Max)
    }

    /// <summary>
    /// Host-only autosave request flag on the director entity (added at spawn). RunDirectorSystem sets
    /// <see cref="Pending"/>=1 on the terminal bank; the managed SaveWriteSystem reads it, writes the JSON save,
    /// and clears it. A plain byte => Burst-safe (no managed/string/file touch in the sim loop).
    /// </summary>
    public struct SaveRequest : IComponentData
    {
        public byte Pending;
    }
}