using UnityEngine;

namespace CSharpESP.Drawing
{
    public static class RenderHelper
    {
        private static Texture2D s_WhiteTexture;
        private static GUIStyle s_StringStyle;

        public static Texture2D WhiteTexture
        {
            get
            {
                if (s_WhiteTexture == null)
                {
                    s_WhiteTexture = new Texture2D(1, 1, TextureFormat.RGBA32, false);
                    s_WhiteTexture.SetPixel(0, 0, Color.white);
                    s_WhiteTexture.Apply();
                }
                return s_WhiteTexture;
            }
        }

        public static GUIStyle StringStyle
        {
            get
            {
                if (s_StringStyle == null)
                {
                    s_StringStyle = new GUIStyle(GUI.skin.label)
                    {
                        alignment = TextAnchor.MiddleCenter,
                        fontSize = 12,
                        fontStyle = FontStyle.Bold
                    };
                    s_StringStyle.normal.textColor = Color.white;
                }
                return s_StringStyle;
            }
        }

        public static void DrawLine(Vector2 pointA, Vector2 pointB, Color color, float thickness = 1f)
        {
            Color oldColor = GUI.color;
            GUI.color = color;

            Vector2 diff = pointB - pointA;
            float angle = Mathf.Rad2Deg * Mathf.Atan2(diff.y, diff.x);
            float length = diff.magnitude;

            GUIUtility.RotateAroundPivot(angle, pointA);
            GUI.DrawTexture(new Rect(pointA.x, pointA.y - (thickness / 2f), length, thickness), WhiteTexture);
            GUIUtility.RotateAroundPivot(-angle, pointA);

            GUI.color = oldColor;
        }

        public static void DrawBox(Rect rect, Color color, float thickness = 1.5f)
        {
            DrawLine(new Vector2(rect.xMin, rect.yMin), new Vector2(rect.xMax, rect.yMin), color, thickness);
            DrawLine(new Vector2(rect.xMax, rect.yMin), new Vector2(rect.xMax, rect.yMax), color, thickness);
            DrawLine(new Vector2(rect.xMax, rect.yMax), new Vector2(rect.xMin, rect.yMax), color, thickness);
            DrawLine(new Vector2(rect.xMin, rect.yMax), new Vector2(rect.xMin, rect.yMin), color, thickness);
        }

        public static void DrawCornerBox(Rect rect, Color color, float cornerLength = 8f, float thickness = 1.5f)
        {
            float w = Mathf.Min(cornerLength, rect.width / 3f);
            float h = Mathf.Min(cornerLength, rect.height / 3f);

            // Top-Left
            DrawLine(new Vector2(rect.xMin, rect.yMin), new Vector2(rect.xMin + w, rect.yMin), color, thickness);
            DrawLine(new Vector2(rect.xMin, rect.yMin), new Vector2(rect.xMin + h, rect.yMin), color, thickness);

            // Top-Right
            DrawLine(new Vector2(rect.xMax, rect.yMin), new Vector2(rect.xMax - w, rect.yMin), color, thickness);
            DrawLine(new Vector2(rect.xMax, rect.yMin), new Vector2(rect.xMax + h, rect.yMin), color, thickness);

            // Bottom-Left
            DrawLine(new Vector2(rect.xMin, rect.yMax), new Vector2(rect.xMin + w, rect.yMax), color, thickness);
            DrawLine(new Vector2(rect.xMin, rect.yMax), new Vector2(rect.xMin - h, rect.yMax), color, thickness);

            // Bottom-Right
            DrawLine(new Vector2(rect.xMax, rect.yMax), new Vector2(rect.xMax - w, rect.yMax), color, thickness);
            DrawLine(new Vector2(rect.xMax, rect.yMax), new Vector2(rect.xMax - h, rect.yMax), color, thickness);
        }

        public static void DrawString(Vector2 pos, string text, Color color, bool centered = true)
        {
            GUIContent content = new GUIContent(text);
            Vector2 size = StringStyle.CalcSize(content);
            Rect r = centered ? new Rect(pos.x - (size.x / 2f), pos.y - (size.y / 2f), size.x, size.y) : new Rect(pos.x, pos.y, size.x, size.y);

            // Drop shadow outline for high contrast
            GUI.color = Color.black;
            GUI.Label(new Rect(r.x - 1, r.y, r.width, r.height), content, StringStyle);
            GUI.Label(new Rect(r.x + 1, r.y, r.width, r.height), content, StringStyle);
            GUI.Label(new Rect(r.x, r.y - 1, r.width, r.height), content, StringStyle);
            GUI.Label(new Rect(r.x, r.y + 1, r.width, r.height), content, StringStyle);

            GUI.color = color;
            GUI.Label(r, content, StringStyle);
            GUI.color = Color.white;
        }
    }
}