import 'package:flutter/material.dart';

/// Predefined paint configurations for common annotation styles.
///
/// Each preset defines a color and stroke width for drawing.
/// Stroke width is normalized (relative to canvas width).
class PaintPreset {
  /// Display name for the preset
  final String name;

  /// Color of the paint (including opacity)
  final Color color;

  /// Stroke width in normalized units (relative to canvas width)
  /// A value of 0.005 means the stroke is 0.5% of the canvas width
  final double strokeWidth;

  /// Icon to display for this preset
  final IconData icon;

  const PaintPreset({
    required this.name,
    required this.color,
    required this.strokeWidth,
    required this.icon,
  });

  // ---------------------------------------------------------------------------
  // Default Presets
  // ---------------------------------------------------------------------------

  /// Black pen for writing/notes
  static const blackPen = PaintPreset(
    name: 'Black Pen',
    color: Colors.black,
    strokeWidth: 0.003, // Thin line for writing
    icon: Icons.edit,
  );

  /// Red pen for corrections/markings
  static const redPen = PaintPreset(
    name: 'Red Pen',
    color: Colors.red,
    strokeWidth: 0.003,
    icon: Icons.edit,
  );

  /// Blue pen for annotations
  static const bluePen = PaintPreset(
    name: 'Blue Pen',
    color: Colors.blue,
    strokeWidth: 0.003,
    icon: Icons.edit,
  );

  /// Yellow highlighter (semi-transparent, thicker)
  static const yellowMarker = PaintPreset(
    name: 'Yellow Marker',
    color: Color(0x80FFEB3B), // Yellow with 50% opacity
    strokeWidth: 0.015, // Thicker for highlighting
    icon: Icons.highlight,
  );

  /// Green highlighter
  static const greenMarker = PaintPreset(
    name: 'Green Marker',
    color: Color(0x804CAF50), // Green with 50% opacity
    strokeWidth: 0.015,
    icon: Icons.highlight,
  );

  /// Pink highlighter
  static const pinkMarker = PaintPreset(
    name: 'Pink Marker',
    color: Color(0x80E91E63), // Pink with 50% opacity
    strokeWidth: 0.015,
    icon: Icons.highlight,
  );

  /// All available default presets
  static const List<PaintPreset> defaults = [
    blackPen,
    redPen,
    bluePen,
    yellowMarker,
    greenMarker,
    pinkMarker,
  ];

  /// Quick access presets (shown in main toolbar)
  static const List<PaintPreset> quickAccess = [
    blackPen,
    redPen,
    yellowMarker,
  ];

  @override
  bool operator ==(Object other) {
    if (identical(this, other)) return true;
    return other is PaintPreset &&
        other.name == name &&
        other.color == color &&
        other.strokeWidth == strokeWidth;
  }

  @override
  int get hashCode => Object.hash(name, color, strokeWidth);
}