import 'package:flutter/material.dart';

class CutCornerClipper extends StatelessWidget {

  const CutCornerClipper({super.key,
    this.width,
    this.height,
    this.cutCorner = CutCorner.topRight,
    this.cutSize,
    this.child,
  });

  final double? width;
  final double? height;
  final CutCorner cutCorner;
  final double? cutSize;
  final Widget? child;

  @override
  Widget build(BuildContext context) {
    return ClipPath(
      clipper: EqualCutCornerClipper(
        cutSize: cutSize ?? 35,
        corner: cutCorner,
      ),
      child: Container(
        width: width,
        height: height,
        decoration: BoxDecoration(
          color: Colors.white,
        ),
        child: child,
      ),
    );
  }
}

/// 长方形缺一个角（等边缺角）
class EqualCutCornerClipper extends CustomClipper<Path> {
  final double cutSize; // 缺角两条直角边的长度（相等）
  final CutCorner corner;

  const EqualCutCornerClipper({
    this.cutSize = 20,
    this.corner = CutCorner.topRight,
  });

  @override
  Path getClip(Size size) {
    final path = Path();
    final w = size.width;
    final h = size.height;
    final c = cutSize;

    switch (corner) {
      case CutCorner.topRight:
        path.moveTo(0, 0);
        path.lineTo(w - c, 0); // 上边到缺角起点
        path.lineTo(w, c);     // 🔥 45° 斜线（两条边相等）
        path.lineTo(w, h);
        path.lineTo(0, h);
        break;

      case CutCorner.topLeft:
        path.moveTo(c, 0);
        path.lineTo(w, 0);
        path.lineTo(w, h);
        path.lineTo(0, h);
        path.lineTo(0, c);
        break;

      case CutCorner.bottomRight:
        path.moveTo(0, 0);
        path.lineTo(w, 0);
        path.lineTo(w, h - c);
        path.lineTo(w - c, h);
        path.lineTo(0, h);
        break;

      case CutCorner.bottomLeft:
        path.moveTo(0, 0);
        path.lineTo(w, 0);
        path.lineTo(w, h);
        path.lineTo(c, h);
        path.lineTo(0, h - c);
        break;
    }
    path.close();
    return path;
  }

  @override
  bool shouldReclip(covariant CustomClipper<Path> oldClipper) {
    if (oldClipper is EqualCutCornerClipper) {
      return oldClipper.cutSize != cutSize || oldClipper.corner != corner;
    }
    return true;
  }
}

enum CutCorner { topLeft, topRight, bottomLeft, bottomRight }