// Copyright 2012 ESRI
// 
// All rights reserved under the copyright laws of the United States
// and applicable international laws, treaties, and conventions.
// 
// You may freely redistribute and use this sample code, with or
// without modification, provided you include the original copyright
// notice and use restrictions.
// 
// See the use restrictions.
// 

using System;
using System.Collections.Generic;
using System.Runtime.InteropServices;
using System.Windows.Forms;
using ESRI.ArcGIS.ADF.CATIDs;
using ESRI.ArcGIS.esriSystem;
using ESRI.ArcGIS.Framework;
using ESRI.ArcGIS.Geodatabase;
using Timestamper.Properties;

namespace Timestamper
{
  /// <summary>
  /// A property page for object classes extended with the TimestampClassExtension.
  /// </summary>
  [Guid("a77c1137-bbca-4e6b-863a-0fad7e3fc4a3")]
  [ClassInterface(ClassInterfaceType.None)]
  [ProgId("Timestamper.TimestampPropertyPage")]
  [ComVisible(true)]
  public partial class TimestampPropertyPage : UserControl, IComPropertyPage
  {
    #region Member Variables
    /// <summary>
    /// Indicates whether the combo boxes have been changed.
    /// </summary>
    private Boolean dirtyFlag = false;

    /// <summary>
    /// The dialog box containing the page.
    /// </summary>
    private IComPropertyPageSite pageSite = null;

    /// <summary>
    /// The extension the property page refers to.
    /// </summary>
    private TimestampClassExtension timestampClassExtension = null;

    /// <summary>
    /// The class the extension is associated with.
    /// </summary>
    private IObjectClass objectClass = null;
    #endregion

    #region Constructors
    /// <summary>
    /// The default constructor.
    /// </summary>
    public TimestampPropertyPage()
    {
      InitializeComponent();

      // Set all combo boxes to "Not Used" by default.
      cmbCreatedField.SelectedIndex = 0;
      cmbModifiedField.SelectedIndex = 0;
      cmbUserField.SelectedIndex = 0;
    }
    #endregion

    #region Private Methods
    /// <summary>
    /// Fired by a change to the combo boxes.
    /// </summary>
    /// <param name="eventSource">The source of the event.</param>
    /// <param name="arguments">Event arguments.</param>
    private void SetDirty(object eventSource, EventArgs arguments)
    {
      dirtyFlag = true;

      if (pageSite != null && this.Visible)
      {
        pageSite.PageChanged();
      }
    }

    /// <summary>
    /// Load valid date and text fields from the class.
    /// </summary>
    private void LoadValidFields()
    {
      // Create lists for storing Date and Text fields.
      List<String> dateFieldNames = new List<String>();
      List<String> textFieldNames = new List<String>();

      // Iterate through the class' fields.
      IFields fields = objectClass.Fields;
      for (int i = 0; i < fields.FieldCount; i++)
      {
        IField field = fields.get_Field(i);
        if (field.Type == esriFieldType.esriFieldTypeDate)
        {
          dateFieldNames.Add(field.Name);
        }
        if (field.Type == esriFieldType.esriFieldTypeString)
        {
          textFieldNames.Add(field.Name);
        }
      }

      // Add the valid fields to each combo box.
      foreach (String dateFieldName in dateFieldNames)
      {
        cmbCreatedField.Items.Add(dateFieldName);
        cmbModifiedField.Items.Add(dateFieldName);
      }
      foreach (String textFieldName in textFieldNames)
      {
        cmbUserField.Items.Add(textFieldName);
      }
    }
    #endregion

    #region IComPropertyPage Members
    /// <summary>
    /// Occurs on page creation.
    /// </summary>
    /// <returns>The handle of the page.</returns>
    int IComPropertyPage.Activate()
    {
      if (timestampClassExtension != null)
      {
        // Load the potential date/text fields from the class.
        LoadValidFields();

        // Set the combo boxes selected indexes to the correct positions.
        if (cmbCreatedField.Items.Contains(timestampClassExtension.CreatedField))
        {
          cmbCreatedField.SelectedItem = timestampClassExtension.CreatedField;
        }
        if (cmbModifiedField.Items.Contains(timestampClassExtension.ModifiedField))
        {
          cmbModifiedField.SelectedItem = timestampClassExtension.ModifiedField;
        }
        if (cmbUserField.Items.Contains(timestampClassExtension.UserField))
        {
          cmbUserField.SelectedItem = timestampClassExtension.UserField;
        }

        // Register the event handler with the combo boxes.
        cmbCreatedField.SelectedIndexChanged += new EventHandler(SetDirty);
        cmbModifiedField.SelectedIndexChanged += new EventHandler(SetDirty);
        cmbUserField.SelectedIndexChanged += new EventHandler(SetDirty);
      }

      return this.Handle.ToInt32();
    }

    /// <summary>
    /// Indicates if the page applies to the specified objects.
    /// Do not hold on to the objects here.
    /// </summary>
    bool IComPropertyPage.Applies(ISet objects)
    {
      // Should only apply if a single class is selected.
      if (objects == null || objects.Count != 1)
        return false;

      // Check whether the provided object is an object class with the TimestampClassExtension.
      Boolean isApplicable = false;
      objects.Reset();
      object providedObject = objects.Next();
      IObjectClass objectClass = providedObject as IObjectClass;
      if (objectClass != null)
      {
        // Get the object class' extension.
        object classExtension = objectClass.Extension;
        if (classExtension is TimestampClassExtension)
        {
          isApplicable = true;
        }
      }

      return isApplicable;
    }

    /// <summary>
    /// Applies any changes to the class extension.
    /// </summary>
    void IComPropertyPage.Apply()
    {
      if (dirtyFlag)
      {
        try
        {
          if (timestampClassExtension != null)
          {
            // Get the field names from the combo boxes.
            String createdField = Convert.ToString(cmbCreatedField.SelectedItem);
            String modifiedField = Convert.ToString(cmbModifiedField.SelectedItem);
            String userField = Convert.ToString(cmbUserField.SelectedItem);
            
            // Check if any of the fields are set to "Not Used".
            if (cmbCreatedField.SelectedIndex == 0)
            {
              createdField = "";
            }
            if (cmbModifiedField.SelectedIndex == 0)
            {
              modifiedField = "";
            }
            if (cmbUserField.SelectedIndex == 0)
            {
              userField = "";
            }

            // Set the field names on the extension.
            timestampClassExtension.SetTimestampFields(createdField, modifiedField, userField);
          }
        }
        catch (Exception exc)
        {
          MessageBox.Show(String.Format("{0}{1}{2}", Resources.PropertyPageApplyErrorMsg,
            Environment.NewLine, exc.Message));
        }
      }
    }

    /// <summary>
    /// Cancels any changes to the class extension.
    /// </summary>
    void IComPropertyPage.Cancel()
    {
      dirtyFlag = false;
    }

    /// <summary>
    /// Destroys the page.
    /// </summary>
    void IComPropertyPage.Deactivate()
    {
      this.Dispose(true);
    }

    /// <summary>
    /// The height of the page in pixels.
    /// </summary>
    int IComPropertyPage.Height
    {
      get { return this.Height; }
    }

    /// <summary>
    /// The help context ID for the specified control on the page.
    /// </summary>
    /// <param name="controlID">The control ID.</param>
    /// <returns>In this case, 0, indicating no help context.</returns>
    int IComPropertyPage.get_HelpContextID(int controlID)
    {
      return 0;
    }

    /// <summary>
    /// The help file for the page (none).
    /// </summary>
    String IComPropertyPage.HelpFile
    {
      get { return string.Empty; }
    }

    /// <summary>
    /// Hides the page.
    /// </summary>
    void IComPropertyPage.Hide()
    {
      // No need to do anything here.
    }

    /// <summary>
    /// Indicates if any changes have been made to the page.
    /// </summary>
    Boolean IComPropertyPage.IsPageDirty
    {
      get { return dirtyFlag; }
    }

    /// <summary>
    /// The sheet that contains the page.
    /// </summary>
    IComPropertyPageSite IComPropertyPage.PageSite
    {
      set
      {
        pageSite = value;
      }
    }

    /// <summary>
    /// The page priority.
    /// </summary>
    int IComPropertyPage.Priority
    {
      get
      {
        // Low-priority.
        return 0;
      }
      set
      {
        // Do nothing.
      }
    }

    /// <summary>
    /// Supplies the page with the object(s) to be edited.
    /// </summary>
    /// <param name="objects">The object(s) this page applies to.</param>
    void IComPropertyPage.SetObjects(ISet objects)
    {
      if (objects == null || objects.Count != 1)
        return;

      // Store the provided object class in a member variable.
      objects.Reset();
      object providedObject = objects.Next();
      objectClass = providedObject as IObjectClass;
      if (objectClass != null)
      {
        // Get the object class' extension.
        timestampClassExtension = objectClass.Extension as TimestampClassExtension;
      }
    }

    /// <summary>
    /// Shows the page.
    /// </summary>
    void IComPropertyPage.Show()
    {
      // No need to do anything here.
    }

    /// <summary>
    /// The title of the property page.
    /// </summary>
    string IComPropertyPage.Title
    {
      get
      {
        return Resources.PropertyPageTitle;
      }
      set
      {
        // Do nothing.
      }
    }

    /// <summary>
    /// The width of the page in pixels.
    /// </summary>
    int IComPropertyPage.Width
    {
      get { return this.Width; }
    }
    #endregion

    #region COM Registration Functions
    /// <summary>
    /// Registers the property page in the appropriate component categories.
    /// </summary>
    /// <param name="registerType">The class description's type.</param>
    [ComRegisterFunction()]
    [ComVisible(false)]
    static void RegisterFunction(Type registerType)
    {
      string regKey = string.Format("HKEY_CLASSES_ROOT\\CLSID\\{{{0}}}", registerType.GUID);
      TablePropertyPages.Register(regKey);
      FeatureClassPropertyPages.Register(regKey);
    }

    /// <summary>
    /// Removes the property page from the appropriate component categories.
    /// </summary>
    /// <param name="registerType">The class description's type.</param>
    [ComUnregisterFunction()]
    [ComVisible(false)]
    static void UnregisterFunction(Type registerType)
    {
      string regKey = string.Format("HKEY_CLASSES_ROOT\\CLSID\\{{{0}}}", registerType.GUID);
      TablePropertyPages.Unregister(regKey);
      FeatureClassPropertyPages.Unregister(regKey);
    }
    #endregion
  }
}