using UnityEngine;

public class FlattenVoxelTreeDebugger : MonoBehaviour
{
    public bool enableDraw = false;

    [Header("Voxel Tree Data")]
    public ComputeBuffer nodeBuffer;        // buffer GPU (optionnel)
    public LinearNode[] nodes;              // ou data CPU (si tu l’as)
    public Vector3 rootCenter = Vector3.zero;
    public float rootHalfSize = 100f;
    public bool showOnlyLeaves = false;
    public bool useGPUBuffer = false;

    [Header("Display Settings")]
    public Color nodeColor = new Color(0f, 1f, 0f, 0.05f);
    public Color leafColor = new Color(1f, 0f, 0f, 0.15f);
    public Color borderColor = Color.yellow;
    public int maxDepthToDraw = 6;
    public VoxelTreeManager voxelTreeManager;


    private void OnDrawGizmos()
    {
        if (enableDraw == false)
            return;

        if (nodes == null && voxelTreeManager.gpuRayCaster != null )
        {
            nodes = voxelTreeManager.gpuRayCaster.linearTree.nodes;
        }
        
        if (nodes == null || nodes.Length == 0)
            return;

        Gizmos.matrix = Matrix4x4.identity;
        DrawNodeRecursive(0, rootCenter, rootHalfSize, 0);
    }

    private void DrawNodeRecursive(int nodeIndex, Vector3 center, float halfSize, int depth)
    {
        if (nodeIndex < 0 || nodeIndex >= nodes.Length) return;
        if (depth > maxDepthToDraw) return;

        var node = nodes[nodeIndex];

        bool isLeaf = node.isLeaf == 1;
        bool isOccupied = node.isOccupied == 1;

        // Color based on node type
        if (isOccupied)
            Gizmos.color = leafColor;
        else
            Gizmos.color = nodeColor;

        if (!showOnlyLeaves || isLeaf)
        {
            Gizmos.DrawCube(center, Vector3.one * (halfSize * 2f));
            Gizmos.color = borderColor;
            Gizmos.DrawWireCube(center, Vector3.one * (halfSize * 2f));
        }

        if (node.childMask != 0)
        {
            float childHalf = halfSize * 0.5f;

            int realIndex = 0;
                
            for (int i = 0; i < 8; i++)
            {
                bool childExists = (node.childMask & (1u << i)) != 0 ;
                if (!childExists) continue;

                Vector3 offset = childHalf * new Vector3(
                    (i & 4) != 0 ? 1f : -1f, // X
                    (i & 2) != 0 ? 1f : -1f, // Y
                    (i & 1) != 0 ? 1f : -1f  // Z
                );

                Vector3 childCenter = center + offset;

                int childIndex = node.childBase + realIndex;

                DrawNodeRecursive(childIndex, childCenter, childHalf, depth + 1);

                realIndex++;
            }
        }


    }

    // Optionnel : utilitaire pour extraire depuis un ComputeBuffer (GPU -> CPU)
    public void SyncFromGPU()
    {
        if (nodeBuffer == null || !useGPUBuffer) return;
        if (nodes == null || nodes.Length == 0)
            nodes = new LinearNode[nodeBuffer.count];

        nodeBuffer.GetData(nodes);
    }
}