using Unity.Entities;
using Unity.Mathematics;

namespace ProjectM.Simulation
{
    /// <summary>
    /// Singleton baked into the gameplay subscene describing the shared home base: a fixed anchor
    /// position and the planar build-grid coordinate space (origin + cell size + extent) that M6 build
    /// placement snaps structures into and M7 production chains tick inside. Flat and blittable (no
    /// entity refs) so it stays deterministic across both worlds and serialization-friendly for later
    /// persistence. Present identically on client and server (baked, not replicated).
    /// </summary>
    public struct BaseAnchor : IComponentData
    {
        /// <summary>World-space center of the plot; also the player spawn-ring center. Equals BaseGridMath.PlotCenter(this).</summary>
        public float3 AnchorPos;

        /// <summary>World-space min-XZ CORNER of cell (0,0). Y is the base plane. Baked = AnchorPos - (GridDims*CellSize)/2 on XZ.</summary>
        public float3 GridOrigin;

        /// <summary>Size of one square grid cell in world units.</summary>
        public float CellSize;

        /// <summary>Grid extent in cells along X and Z; valid cell indices are [0, GridDims).</summary>
        public int2 GridDims;
    }
}