zaaReloaded2/zaaReloaded2/ViewModels/SettingsViewModel.cs

/* SettingsViewModel.cs
 * part of zaaReloaded2
 * 
 * Copyright 2015 Daniel Kraus
 * 
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 * 
 *     http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
using System;
using System.Collections.Generic;
using System.Diagnostics;
using System.Linq;
using System.Text;
using Bovender.Mvvm;
using Bovender.Mvvm.ViewModels;
using Bovender.Mvvm.Messaging;
using zaaReloaded2.Controller;
using zaaReloaded2.Controller.Elements;
using zaaReloaded2.Formatter;

namespace zaaReloaded2.ViewModels
{
    /// <summary>
    /// View model for the zaaReloaded2.Controller.Settings class.
    /// </summary>
    public class SettingsViewModel : ViewModelBase, ICloneable
    {
        #region Properties

        /// <summary>
        /// Gets or sets the name of the Settings
        /// </summary>
        public string Name
        {
            [DebuggerStepThrough]
            get
            {
                return _settings.Name;
            }
            [DebuggerStepThrough]
            set
            {
                _settings.Name = value;
                OnPropertyChanged("Name");
            }
        }

        /// <summary>
        /// Is true if the settings' name is editable.
        /// If the settings' name is a default, preconfigured name,
        /// this will be false.
        /// </summary>
        public bool IsNameEnabled
        {
            get
            {
                return (Name != Properties.Settings.Default.SettingsNameClinic) &&
                    (Name != Properties.Settings.Default.SettingsNameWard);
            }
        }

        /// <summary>
        /// Gets a list of element view models.
        /// </summary>
        public IList<ElementViewModel> Elements
        {
            get
            {
                if (_elements == null) { _elements = new List<ElementViewModel>(); }
                return _elements;
            }
        }

        /// <summary>
        /// Gets or sets the currently selected element.
        /// </summary>
        public ElementViewModel SelectedElement
        {
            get { return _selectedElement; }
            set
            {
                _selectedElement = value;
                OnPropertyChanged("SelectedElement");
            }
        }

        /// <summary>
        /// Returns an EnumProvider object for the ReferenceStyle
        /// </summary>
        public EnumProvider<ReferenceStyle> ReferenceStyle
        {
            get
            {
                if (_referenceStyle == null)
                {
                    _referenceStyle = new EnumProvider<ReferenceStyle>(_settings.ReferenceStyle);
                }
                return _referenceStyle;
            }
        }

        #endregion

        #region Constructors

        public SettingsViewModel()
            : this(new Settings())
        { }

        public SettingsViewModel(Settings settings)
            : base()
        {
            _settings = settings;
            _elements = new List<ElementViewModel>();
            foreach (ElementBase element in settings.Elements)
            {
                ElementViewModel vm;
                if (element is FormatElementBase)
                {
                    vm = new FormatElementViewModel(element as FormatElementBase);
                }
                else if (element is ControlElementBase)
                {
                    vm = new ControlElementViewModel(element as ControlElementBase);
                }
                else
                {
                    throw new InvalidOperationException(
                        "Cannot create ViewModel for " + element.GetType().ToString());
                }
                AddElementViewModel(vm);
            }
        }

        #endregion

        #region Messages

        #endregion

        #region Commands

        public DelegatingCommand AddElementCommand
        {
            get
            {
                if (_addElementCommand == null)
                {
                    _addElementCommand = new DelegatingCommand(
                        param => DoAddElement());
                }
                return _addElementCommand;
            }
        }

        public DelegatingCommand AddChildElementCommand
        {
            get
            {
                if (_addChildElementCommand == null)
                {
                    _addChildElementCommand = new DelegatingCommand(
                        param => DoAddChildElement(),
                        param => CanAddChildElement());
                }
                return _addChildElementCommand;
            }
        }

        public DelegatingCommand DeleteElementCommand
        {
            get
            {
                if (_deleteElementCommand == null)
                {
                    _deleteElementCommand = new DelegatingCommand(
                        param => DoDeleteElement(),
                        param => CanDeleteElement());
                }
                return _deleteElementCommand;
            }
        }

        public DelegatingCommand CopyElementCommand
        {
            get
            {
                if (_copyElementCommand == null)
                {
                    _copyElementCommand = new DelegatingCommand(
                        param => DoCopyElement(),
                        param => CanCopyElement());
                }
                return _copyElementCommand;
            }
        }

        #endregion

        #region Public methods

        /// <summary>
        /// Wires the OnProperty changed event of an ElementViewModel's
        /// wrapped model and adds the view model to the Elements collection.
        /// </summary>
        public void AddElementViewModel(ElementViewModel elementViewModel)
        {
            elementViewModel.PropertyChanged += ElementViewModel_PropertyChanged;
            Elements.Add(elementViewModel);
        }

        /// <summary>
        /// Wires the OnProperty changed event of an ElementViewModel's
        /// wrapped model and adds the view model as a child of another
        /// view model.
        /// </summary>
        public void AddChildElementViewModel(ControlElementViewModel parent, FormatElementViewModel child)
        {
            child.PropertyChanged += ElementViewModel_PropertyChanged;
            parent.AddChildElement(child);
        }

        #endregion

        #region Private methods

        void DoAddElement() { }

        void DoAddChildElement() { }

        bool CanAddChildElement()
        {
            return SelectedElement is ControlElementViewModel;
        }

        void DoDeleteElement() { }

        bool CanDeleteElement() { return _selectedElement != null; }

        void DoCopyElement() { }

        bool CanCopyElement() { return _selectedElement != null; }

        /// <summary>
        /// Sets or unsets the SelectedElement property whenever the IsSelected
        /// property of an ElementViewModel changes.
        /// </summary>
        void ElementViewModel_PropertyChanged(object sender, System.ComponentModel.PropertyChangedEventArgs e)
        {
            ElementViewModel vm = sender as ElementViewModel;
            if (vm != null && e.PropertyName == "IsSelected")
            {
                SelectedElement = vm.IsSelected ? vm : null;
            }
        }

        #endregion

        #region Implementation of ViewModelBase

        public override object RevealModelObject()
        {
            return _settings;
        }

        #endregion

        #region Implementation of ICloneable

        public object Clone()
        {
            return new SettingsViewModel(_settings.Clone() as Settings);
        }

        #endregion

        #region Fields

        Settings _settings;
        DelegatingCommand _addElementCommand;
        DelegatingCommand _addChildElementCommand;
        DelegatingCommand _deleteElementCommand;
        DelegatingCommand _copyElementCommand;
        
        List<ElementViewModel> _elements;
        ElementViewModel _selectedElement;
        EnumProvider<ReferenceStyle> _referenceStyle;

        #endregion
    }
}