using System;
using System.ComponentModel;

namespace Netron.Diagramming.Core {
  /// <summary>
  /// Abstract base class for custom descriptors based on our properties mechanism.
  /// <remarks>
  /// Usually you do not inherit from this class to describe properties of entities, use the appropriate 
  /// specializations like the <see cref="ShapeBaseDescriptor"/> or <see cref="ConnectionBaseDescriptor"/> classes instead.
  /// Also, this class does not define any properties for the property grid but contains methods and basic stuff to make the construction of
  /// concrete descriptors easier.
  /// </remarks>
  /// </summary>
  abstract class DescriptorBase : CustomTypeDescriptor {
    #region Fields
    //the provider to which this descriptor is attached
    private TypeDescriptionProvider provider;
    /// <summary>
    /// the type being served
    /// </summary>
    private Type type;
    /// <summary>
    /// the collection of properties displayed
    /// </summary>
    private PropertyDescriptorCollection mProperties;
    #endregion

    #region Properties
    /// <summary>
    /// Gets the collection of property descrtiptors
    /// </summary>
    protected PropertyDescriptorCollection Properties {
      get { return mProperties; }
    }
    #endregion

    #region Constructors

    /// <summary>
    /// Initializes a new instance of the <see cref="T:DescriptorBase"/> class.
    /// </summary>
    /// <param name="provider">The provider.</param>
    /// <param name="parentdescriptor">The parentdescriptor.</param>
    /// <param name="objectType">Type of the object.</param>
    public DescriptorBase(ShapeProvider provider, ICustomTypeDescriptor parentdescriptor, Type objectType)
      : base(parentdescriptor) {
      this.provider = provider;
      this.type = objectType;
      mProperties = new PropertyDescriptorCollection(null);
    }

    /// <summary>
    /// Initializes a new instance of the <see cref="T:DescriptorBase"/> class.
    /// </summary>
    /// <param name="provider">The provider.</param>
    /// <param name="objectType">Type of the object.</param>
    public DescriptorBase(TypeDescriptionProvider provider, Type objectType)
      : base() {
      this.provider = provider;
      this.type = objectType;
      mProperties = new PropertyDescriptorCollection(null);
    }
    #endregion

    #region Methods

    #region AddProperty overloads
    /// <summary>
    /// Adds a new property to the property descriptor collection.
    /// </summary>
    /// <param name="name">The name of the property displayed in the property grid.</param>
    /// <param name="type">The fully qualified name of the type of the property.</param>
    public void AddProperty(string name, Type type) {
      PropertySpec widthSpec = new PropertySpec(name, type);
      PropertySpecDescriptor pd = widthSpec.ToPropertyDescriptor();
      pd.OnGetValue += new EventHandler<PropertyEventArgs>(GetValue);
      pd.OnSetValue += new EventHandler<PropertyEventArgs>(SetValue);
      mProperties.Add(pd);
    }
    /// <summary>
    /// Adds a new property to the property descriptor collection.
    /// </summary>
    /// <param name="name">The name of the property displayed in the property grid.</param>
    /// <param name="type">The fully qualified name of the type of the property.</param>
    /// <param name="category">The category under which the property is displayed in the
    /// property grid.</param>
    public void AddProperty(string name, Type type, string category) {
      PropertySpec widthSpec = new PropertySpec(name, type, category);
      PropertySpecDescriptor pd = widthSpec.ToPropertyDescriptor();
      pd.OnGetValue += new EventHandler<PropertyEventArgs>(GetValue);
      pd.OnSetValue += new EventHandler<PropertyEventArgs>(SetValue);
      mProperties.Add(pd);
    }
    /// <summary>
    /// Adds a new property to the property descriptor collection.
    /// </summary>
    /// <param name="name">The name of the property displayed in the property grid.</param>
    /// <param name="type">The fully qualified name of the type of the property.</param>
    /// <param name="category">The category under which the property is displayed in the
    /// property grid.</param>
    /// <param name="description">A string that is displayed in the help area of the
    /// property grid.</param>
    public void AddProperty(string name, Type type, string category, string description) {
      PropertySpec widthSpec = new PropertySpec(name, type, category, description);
      PropertySpecDescriptor pd = widthSpec.ToPropertyDescriptor();
      pd.OnGetValue += new EventHandler<PropertyEventArgs>(GetValue);
      pd.OnSetValue += new EventHandler<PropertyEventArgs>(SetValue);
      mProperties.Add(pd);
    }
    /// <summary>
    /// Adds a new property to the property descriptor collection.
    /// </summary>
    /// <param name="name">The name of the property displayed in the property grid.</param>
    /// <param name="type">The fully qualified name of the type of the property.</param>
    /// <param name="category">The category under which the property is displayed in the
    /// property grid.</param>
    /// <param name="description">A string that is displayed in the help area of the
    /// property grid.</param>
    /// <param name="defaultValue">The default value of the property, or null if there is
    /// no default value.</param>
    public void AddProperty(string name, Type type, string category, string description, object defaultValue) {
      PropertySpec widthSpec = new PropertySpec(name, type, category, description, defaultValue);
      PropertySpecDescriptor pd = widthSpec.ToPropertyDescriptor();
      pd.OnGetValue += new EventHandler<PropertyEventArgs>(GetValue);
      pd.OnSetValue += new EventHandler<PropertyEventArgs>(SetValue);
      mProperties.Add(pd);
    }
    /// <summary>
    /// Adds a new property to the property descriptor collection.
    /// </summary>
    /// <param name="name">The name of the property displayed in the property grid.</param>
    /// <param name="type">A Type that represents the type of the property.</param>
    /// <param name="category">The category under which the property is displayed in the
    /// property grid.</param>
    /// <param name="description">A string that is displayed in the help area of the
    /// property grid.</param>
    /// <param name="defaultValue">The default value of the property, or null if there is
    /// no default value.</param>
    /// <param name="editor">The Type that represents the type of the editor for this
    /// property.  This type must derive from UITypeEditor.</param>
    /// <param name="typeConverter">The Type that represents the type of the type
    /// converter for this property.  This type must derive from TypeConverter.</param>
    public void AddProperty(string name, Type type, string category, string description, object defaultValue, Type editor, Type typeConverter) {
      PropertySpec widthSpec = new PropertySpec(name, type, category, description, defaultValue, editor, typeConverter);
      PropertySpecDescriptor pd = widthSpec.ToPropertyDescriptor();
      pd.OnGetValue += new EventHandler<PropertyEventArgs>(GetValue);
      pd.OnSetValue += new EventHandler<PropertyEventArgs>(SetValue);
      mProperties.Add(pd);
    }
    #endregion




    /// <summary>
    /// Overrides the method to retun the collection of properties we defined internally
    /// </summary>
    /// <param name="attributes"></param>
    /// <returns></returns>
    public override PropertyDescriptorCollection GetProperties(Attribute[] attributes) {
      return mProperties;
    }

    /// <summary>
    /// Returns a collection of property descriptors for the object represented by this type descriptor.
    /// </summary>
    /// <returns>
    /// A <see cref="T:System.ComponentModel.PropertyDescriptorCollection"></see> containing the property descriptions for the object represented by this type descriptor. The default is <see cref="F:System.ComponentModel.PropertyDescriptorCollection.Empty"></see>.
    /// </returns>
    public override PropertyDescriptorCollection GetProperties() {
      return GetProperties(null);
    }
    /// <summary>
    /// Override this method to return the appropriate value corresponding to the property
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    protected virtual void GetValue(object sender, PropertyEventArgs e) {

    }

    /// <summary>
    /// Override this method to set the appropriate value corresponding to the property
    /// </summary>
    /// <param name="sender"></param>
    /// <param name="e"></param>
    protected virtual void SetValue(object sender, PropertyEventArgs e) {
    }
    #endregion
  }
}