using UnityEngine;

namespace Amanotes.Core
{
    internal static class Size2DExtensions
    {
        public static void DrawGizmo(this Size2D inst, Transform t)
        {
            if (inst.gizmoMode == GizmoMode.None) return;
            if (inst.gizmoMode != GizmoMode.Always) return;
            
            var dimmedColor = Color.Lerp(inst.gizmoColor, Color.black, 0.3f);
            DrawSizeGizmo(inst, dimmedColor, t);
        }
        
        public static void DrawGizmoSelected(this Size2D inst, Transform t)
        {
            if (inst.gizmoMode == GizmoMode.None) return;
            var brightColor = Color.Lerp(inst.gizmoColor, Color.white, 0.3f);
            DrawSizeGizmo(inst, brightColor, t);
        }
        
        private static void DrawSizeGizmo(Size2D inst, Color color, Transform t)
        {
            var size = (Vector2)inst;
            var halfSize = size * 0.5f;
            var pivotOffset = new Vector2(size.x * (0.5f - inst.pivot.x), size.y * (0.5f - inst.pivot.y));
            
            var localCorners = new Vector3[4];
            
            for (var i = 0; i < 4; i++)
            {
                var x = (i == 1 || i == 2) ? halfSize.x : -halfSize.x;
                var y = (i == 2 || i == 3) ? halfSize.y : -halfSize.y;
                
                if (inst.useZ)
                {
                    // XZ plane (Y up)
                    localCorners[i] = new Vector3(x + pivotOffset.x, 0f, y + pivotOffset.y);
                }
                else
                {
                    // XY plane (Z forward)
                    localCorners[i] = new Vector3(x + pivotOffset.x, y + pivotOffset.y, 0f);
                }
            }
            
            var worldCorners = new Vector3[4];
            for (var i = 0; i < 4; i++)
            {
                worldCorners[i] = t.TransformPoint(localCorners[i]);
            }
            
            Gizmos.color = color;
            
            for (var i = 0; i < 4; i++)
            {
                Gizmos.DrawLine(worldCorners[i], worldCorners[(i + 1) % 4]);
            }
            
            Gizmos.DrawLine(worldCorners[0], worldCorners[2]);
            Gizmos.DrawLine(worldCorners[1], worldCorners[3]);
        }
    }
}