/// Domain models for catalog items shown in lists and detail screens.
library;

import 'package:flutter/material.dart';

/// High-level grouping used for filters, icons, and accent colors.
enum ItemCategory {
  design,
  development,
  productivity,
  lifestyle,
}

extension ItemCategoryX on ItemCategory {
  String get label => switch (this) {
        ItemCategory.design => 'Design',
        ItemCategory.development => 'Development',
        ItemCategory.productivity => 'Productivity',
        ItemCategory.lifestyle => 'Lifestyle',
      };

  IconData get icon => switch (this) {
        ItemCategory.design => Icons.palette_outlined,
        ItemCategory.development => Icons.code,
        ItemCategory.productivity => Icons.bolt_outlined,
        ItemCategory.lifestyle => Icons.spa_outlined,
      };

  /// Stable accent used by [Hero] tiles so the animation has a colored target.
  Color get accent => switch (this) {
        ItemCategory.design => const Color(0xFF7C3AED),
        ItemCategory.development => const Color(0xFF0F766E),
        ItemCategory.productivity => const Color(0xFFC2410C),
        ItemCategory.lifestyle => const Color(0xFF0369A1),
      };

  static ItemCategory fromName(String name) {
    return ItemCategory.values.firstWhere(
      (category) => category.name == name,
      orElse: () => ItemCategory.productivity,
    );
  }

  static ItemCategory fromIndex(int index) {
    return ItemCategory.values[index.abs() % ItemCategory.values.length];
  }
}

/// A catalog entry displayed on Home / Search and opened on the detail route.
class Item {
  const Item({
    required this.id,
    required this.title,
    required this.subtitle,
    required this.description,
    required this.category,
    required this.createdAt,
  });

  final String id;
  final String title;
  final String subtitle;
  final String description;
  final ItemCategory category;
  final DateTime createdAt;

  /// Tag used by the list-to-detail [Hero] animation.
  String get heroTag => 'item-hero-$id';

  Item copyWith({
    String? id,
    String? title,
    String? subtitle,
    String? description,
    ItemCategory? category,
    DateTime? createdAt,
  }) {
    return Item(
      id: id ?? this.id,
      title: title ?? this.title,
      subtitle: subtitle ?? this.subtitle,
      description: description ?? this.description,
      category: category ?? this.category,
      createdAt: createdAt ?? this.createdAt,
    );
  }

  /// Maps a JSONPlaceholder `/posts` payload (or any similar JSON object).
  factory Item.fromJson(Map<String, dynamic> json) {
    final id = json['id']?.toString() ?? '0';
    final title = (json['title'] as String? ?? 'Untitled').trim();
    final body = (json['body'] as String? ?? '').trim();
    final numericId = int.tryParse(id) ?? 0;

    return Item(
      id: 'remote-$id',
      title: _titleCase(title),
      subtitle: _firstSentence(body),
      description: body.replaceAll('\n', ' '),
      category: ItemCategoryX.fromIndex(numericId),
      createdAt: DateTime(2026, 1, 1).add(Duration(days: numericId)),
    );
  }

  Map<String, dynamic> toJson() {
    return {
      'id': id,
      'title': title,
      'subtitle': subtitle,
      'description': description,
      'category': category.name,
      'createdAt': createdAt.toIso8601String(),
    };
  }

  static String _titleCase(String value) {
    if (value.isEmpty) return value;
    return value[0].toUpperCase() + value.substring(1);
  }

  static String _firstSentence(String value) {
    if (value.isEmpty) return 'No summary available.';
    final cleaned = value.replaceAll('\n', ' ');
    final period = cleaned.indexOf('.');
    if (period <= 0) {
      return cleaned.length > 80 ? '${cleaned.substring(0, 77)}…' : cleaned;
    }
    return cleaned.substring(0, period + 1);
  }
}