using System;
using System.Windows;
using System.Windows.Media;
using System.ComponentModel;
using System.Windows.Documents;

namespace SHJX.Service.WorkFlowEdit
{
    public abstract class LinkBase : DiagramItem, ILink, INotifyPropertyChanged
    {
        #region Properties

        #region CanRelink Property

        public bool CanRelink
        {
            get { return (bool)GetValue(CanRelinkProperty); }
            set { SetValue(CanRelinkProperty, value); }
        }

        public static readonly DependencyProperty CanRelinkProperty =
            DependencyProperty.Register("CanRelink", typeof(bool), typeof(LinkBase), new FrameworkPropertyMetadata(true));

        #endregion

        private IPort _source;
        public IPort Source
        {
            get { return _source; }
            set
            {
                if (_source != null)
                    _source.Links.Remove(this);
                _source = value;
                if (_source != null)
                    _source.Links.Add(this);
            }
        }

        private IPort _target;
        public IPort Target
        {
            get { return _target; }
            set
            {
                if (_target != null)
                    _target.Links.Remove(this);
                _target = value;
                if (_target != null)
                    _target.Links.Add(this);
            }
        }

        public Point? SourcePoint { get; set; }
        public Point? TargetPoint { get; set; }


        private bool _startCap;
        public bool StartCap
        {
            get { return _startCap; }
            set
            {
                _startCap = value;
                OnPropertyChanged("StartCap");
            }
        }

        private bool _endCap;
        public bool EndCap
        {
            get { return _endCap; }
            set
            {
                _endCap = value;
                OnPropertyChanged("EndCap");
            }
        }

        private Brush _brush = new SolidColorBrush(Colors.Black);
        public Brush Brush
        {
            get { return _brush; }
            set { _brush = value; }
        }

        private Point _startPoint;
        public Point StartPoint
        {
            get { return _startPoint; }
            protected set
            {
                _startPoint = value;
                OnPropertyChanged("StartPoint");
            }
        }

        private Point _endPoint;
        public Point EndPoint
        {
            get { return _endPoint; }
            protected set
            {
                _endPoint = value;
                OnPropertyChanged("EndPoint");
            }
        }

        private double _startCapAngle;
        public double StartCapAngle
        {
            get { return _startCapAngle; }
            protected set
            {
                _startCapAngle = value;
                OnPropertyChanged("StartCapAngle");
            }
        }

        private double _endCapAngle;
        public double EndCapAngle
        {
            get { return _endCapAngle; }
            protected set
            {
                _endCapAngle = value;
                OnPropertyChanged("EndCapAngle");
            }
        }

        private PathGeometry _pathGeomtry;
        public PathGeometry PathGeometry
        {
            get { return _pathGeomtry; }
            protected set
            {
                _pathGeomtry = value;
                OnPropertyChanged("PathGeometry");
            }
        }

        private Point _labelPosition;
        public Point LabelPosition
        {
            get { return _labelPosition; }
            set
            {
                _labelPosition = value;
                OnPropertyChanged("LabelPosition");
            }
        }

        #region Label Property

        public string Label
        {
            get { return (string)GetValue(LabelProperty); }
            set { SetValue(LabelProperty, value); }
        }

        public static readonly DependencyProperty LabelProperty =
            DependencyProperty.Register("Label", typeof(string), typeof(LinkBase));

        #endregion

        public override Rect Bounds
        {
            get
            {
                var x = Math.Min(StartPoint.X, EndPoint.X);
                var y = Math.Min(StartPoint.Y, EndPoint.Y);
                var mx = Math.Max(StartPoint.X, EndPoint.X);
                var my = Math.Max(StartPoint.Y, EndPoint.Y);
                return new Rect(x, y, mx - x, my - y);
            }
        }

        #endregion

        protected LinkBase()
        {
            UpdatePath();
        }

        protected override Adorner CreateSelectionAdorner()
        {
            return new SelectionAdorner(this, new RelinkControl());
        }

        public abstract void UpdatePath();

        #region INotifyPropertyChanged Members

        public event PropertyChangedEventHandler PropertyChanged;
        protected void OnPropertyChanged(string name)
        {
            PropertyChangedEventHandler handler = PropertyChanged;
            if (handler != null)
                handler(this, new PropertyChangedEventArgs(name));
        }
        #endregion
    }
}