using System;
using UnityEngine;

namespace BumpCombat.Combat
{
    // Authored ground geometry shared by the XY controller and XZ comparison.
    // Sprite frames and decoration consume elapsed time independently of damage ticks.
    public static class CycloneGeometry
    {
        public const float PixelsPerUnit = 32f;
        public const float ShadowLocalY = -7.5f / PixelsPerUnit;
        public const float CenterOffsetY = 5f / PixelsPerUnit;
        public const float FrameSeconds = .05f;

        public static float VisualScale(float range, bool charged) => range / (charged ? 1.25f : .85f);

        public static Vector2 Radii(float range, bool charged) =>
            (charged ? new Vector2(46f, 18f) : new Vector2(38.0625f, 15.03125f))
            / PixelsPerUnit * VisualScale(range, charged);

        public static Vector2 CenterOffset(float range, bool charged, float rootScaleY) =>
            Vector2.up * (ShadowLocalY * rootScaleY + CenterOffsetY * VisualScale(range, charged));

        public static int ScheduledHitCount(float duration, float interval) =>
            duration <= 0f || interval <= 0f ? 1
                : Mathf.Max(1, Mathf.FloorToInt((duration + .0001f) / interval) + 1);

        public static float NormalizedDistance(Vector2 offset, Vector2 radii) =>
            offset.x * offset.x / (radii.x * radii.x)
            + offset.y * offset.y / (radii.y * radii.y);

        // Keep the original closest-point and 64 boundary samples, including tolerances.
        // The adapter supplies Collider2D.ClosestPoint or an XZ circular footprint.
        public static bool Overlaps(Vector2 center, Vector2 radii, Func<Vector2, Vector2> closestPoint)
        {
            if (NormalizedDistance(closestPoint(center) - center, radii) <= 1.0001f) return true;
            const int samples = 64;
            for (int i = 0; i < samples; i++)
            {
                float angle = Mathf.PI * 2f * i / samples;
                Vector2 point = center + new Vector2(Mathf.Cos(angle) * radii.x, Mathf.Sin(angle) * radii.y);
                if ((closestPoint(point) - point).sqrMagnitude <= .000001f) return true;
            }
            return false;
        }
    }
}