using ReactiveUI;
using System;
using System.Collections.ObjectModel;
using System.Collections.Specialized;

namespace AuroraDesk.Core.Entities;

/// <summary>
/// 节点实体 - 表示画布上的一个可拖拽组件
/// </summary>
public class Node : ReactiveObject
{
    private const double MinDimension = 20;
    private const double MaxDimension = 2000;
    private const double MinConnectorSize = 0;
    private const double MaxConnectorSize = 400;

    private double _x;
    private double _y;
    private double _width = 120;
    private double _height = 80;
    private string _title = string.Empty;
    private string _content = string.Empty;
    private bool _isSelected;
    private readonly NotifyCollectionChangedEventHandler _connectionPointsChangedHandler;
    private ObservableCollection<ConnectionPoint> _connectionPoints = new();
    private double _leftConnectorSize = 10;
    private double _rightConnectorSize = 10;
    private string _leftConnectorColor = "#3498DB";
    private string _rightConnectorColor = "#FF6B6B";
    private ConnectorPlacementMode _leftConnectorPlacement = ConnectorPlacementMode.Inside;
    private ConnectorPlacementMode _rightConnectorPlacement = ConnectorPlacementMode.Inside;

    /// <summary>
    /// 构造函数
    /// </summary>
    public Node()
    {
        _connectionPointsChangedHandler = (_, _) => RaiseConnectionPointsChanged();
        _connectionPoints.CollectionChanged += _connectionPointsChangedHandler;
    }

    /// <summary>
    /// 节点唯一标识符
    /// </summary>
    public string Id { get; set; } = Guid.NewGuid().ToString();

    /// <summary>
    /// X坐标位置
    /// </summary>
    public double X
    {
        get => _x;
        set => this.RaiseAndSetIfChanged(ref _x, value);
    }

    /// <summary>
    /// Y坐标位置
    /// </summary>
    public double Y
    {
        get => _y;
        set => this.RaiseAndSetIfChanged(ref _y, value);
    }

    /// <summary>
    /// 节点宽度
    /// </summary>
    public double Width
    {
        get => _width;
        set
        {
            var clamped = Math.Clamp(value, MinDimension, MaxDimension);
            this.RaiseAndSetIfChanged(ref _width, clamped);
        }
    }

    /// <summary>
    /// 节点高度
    /// </summary>
    public double Height
    {
        get => _height;
        set
        {
            var clamped = Math.Clamp(value, MinDimension, MaxDimension);
            this.RaiseAndSetIfChanged(ref _height, clamped);
        }
    }

    /// <summary>
    /// 节点标题
    /// </summary>
    public string Title
    {
        get => _title;
        set => this.RaiseAndSetIfChanged(ref _title, value);
    }

    /// <summary>
    /// 节点内容（显示在节点内部的文本）
    /// </summary>
    public string Content
    {
        get => _content;
        set => this.RaiseAndSetIfChanged(ref _content, value);
    }

    /// <summary>
    /// 是否被选中
    /// </summary>
    public bool IsSelected
    {
        get => _isSelected;
        set => this.RaiseAndSetIfChanged(ref _isSelected, value);
    }

    /// <summary>
    /// 连接点集合
    /// </summary>
    public ObservableCollection<ConnectionPoint> ConnectionPoints
    {
        get => _connectionPoints;
        set
        {
            if (ReferenceEquals(_connectionPoints, value))
            {
                return;
            }

            if (_connectionPoints != null)
            {
                _connectionPoints.CollectionChanged -= _connectionPointsChangedHandler;
            }

            var newCollection = value ?? new ObservableCollection<ConnectionPoint>();
            newCollection.CollectionChanged += _connectionPointsChangedHandler;

            this.RaiseAndSetIfChanged(ref _connectionPoints, newCollection);
            RaiseConnectionPointsChanged();
        }
    }

    /// <summary>
    /// 左侧附件圆尺寸
    /// </summary>
    public double LeftConnectorSize
    {
        get => _leftConnectorSize;
        set
        {
            var clamped = Math.Clamp(value, MinConnectorSize, MaxConnectorSize);
            this.RaiseAndSetIfChanged(ref _leftConnectorSize, clamped);
        }
    }

    /// <summary>
    /// 右侧附件圆尺寸
    /// </summary>
    public double RightConnectorSize
    {
        get => _rightConnectorSize;
        set
        {
            var clamped = Math.Clamp(value, MinConnectorSize, MaxConnectorSize);
            this.RaiseAndSetIfChanged(ref _rightConnectorSize, clamped);
        }
    }

    /// <summary>
    /// 左侧附件圆颜色（Hex）
    /// </summary>
    public string LeftConnectorColor
    {
        get => _leftConnectorColor;
        set => this.RaiseAndSetIfChanged(ref _leftConnectorColor, value);
    }

    /// <summary>
    /// 右侧附件圆颜色（Hex）
    /// </summary>
    public string RightConnectorColor
    {
        get => _rightConnectorColor;
        set => this.RaiseAndSetIfChanged(ref _rightConnectorColor, value);
    }

    /// <summary>
    /// 左侧附件圆定位方式
    /// </summary>
    public ConnectorPlacementMode LeftConnectorPlacement
    {
        get => _leftConnectorPlacement;
        set => this.RaiseAndSetIfChanged(ref _leftConnectorPlacement, value);
    }

    /// <summary>
    /// 右侧附件圆定位方式
    /// </summary>
    public ConnectorPlacementMode RightConnectorPlacement
    {
        get => _rightConnectorPlacement;
        set => this.RaiseAndSetIfChanged(ref _rightConnectorPlacement, value);
    }
    private void RaiseConnectionPointsChanged()
    {
        this.RaisePropertyChanged(nameof(ConnectionPoints));
    }
}