Major OpenDatabaseUserControl refactor, now has proper ViewModel

Status text and password box border colors are updated according to database status
Update composite key in Settings work
Some code cleanup

ModernKeePass/ViewModels/Items/SettingsDatabaseVm.cs

@@ -0,0 +1,110 @@
+using System;
+using System.Collections.Generic;
+using System.Collections.ObjectModel;
+using System.Linq;
+using Windows.Storage;
+using Windows.UI.Xaml;
+using ModernKeePass.Common;
+using ModernKeePass.Interfaces;
+using ModernKeePassLib;
+using ModernKeePassLib.Cryptography.Cipher;
+using ModernKeePassLib.Cryptography.KeyDerivation;
+
+namespace ModernKeePass.ViewModels
+{
+    public class SettingsDatabaseVm: NotifyPropertyChangedBase, IHasSelectableObject
+    {
+        private readonly App _app = Application.Current as App;
+        private readonly ApplicationDataContainer _localSettings = ApplicationData.Current.LocalSettings;
+        private GroupVm _selectedItem;
+
+        public bool HasRecycleBin
+        {
+            get { return _app.Database.RecycleBinEnabled; }
+            set
+            {
+                _app.Database.RecycleBinEnabled = value;
+                OnPropertyChanged();
+            }
+        }
+
+        public ObservableCollection<GroupVm> Groups { get; set; }
+
+        public IEnumerable<string> Ciphers
+        {
+            get
+            {
+                for (var inx = 0; inx < CipherPool.GlobalPool.EngineCount; inx++)
+                {
+                    yield return CipherPool.GlobalPool[inx].DisplayName;
+                }
+            }
+        }
+
+        public int CipherIndex
+        {
+            get
+            {
+                for (var inx = 0; inx < CipherPool.GlobalPool.EngineCount; ++inx)
+                {
+                    if (CipherPool.GlobalPool[inx].CipherUuid.Equals(_app.Database.DataCipher)) return inx;
+                }
+                return -1;
+            }
+            set { _app.Database.DataCipher = CipherPool.GlobalPool[value].CipherUuid; }
+        }
+
+        public IEnumerable<string> Compressions => Enum.GetNames(typeof(PwCompressionAlgorithm)).Take((int)PwCompressionAlgorithm.Count);
+
+        public string CompressionName
+        {
+            get { return Enum.GetName(typeof(PwCompressionAlgorithm), _app.Database.CompressionAlgorithm); }
+            set { _app.Database.CompressionAlgorithm = (PwCompressionAlgorithm)Enum.Parse(typeof(PwCompressionAlgorithm), value); }
+        }
+        public IEnumerable<string> KeyDerivations => KdfPool.Engines.Select(e => e.Name);
+
+        public string KeyDerivationName
+        {
+            get { return KdfPool.Get(_app.Database.KeyDerivation.KdfUuid).Name; }
+            set { _app.Database.KeyDerivation = KdfPool.Engines.FirstOrDefault(e => e.Name == value)?.GetDefaultParameters(); } 
+        }
+
+        public ISelectableModel SelectedItem
+        {
+            get { return Groups.FirstOrDefault(g => g.IsSelected); }
+            set
+            {
+                if (_selectedItem == value) return;
+                if (_selectedItem != null)
+                {
+                    _selectedItem.IsSelected = false;
+                }
+
+                SetProperty(ref _selectedItem, (GroupVm)value);
+
+                if (_selectedItem != null)
+                {
+                    _selectedItem.IsSelected = true;
+                }
+            }
+        }
+
+        public SettingsDatabaseVm()
+        {
+            Groups = _app.Database.RootGroup.Groups;
+        }
+
+        // TODO: Move to another setting class (or a static class)
+        private T GetSetting<T>(string property)
+        {
+            try
+            {
+                return (T) Convert.ChangeType(_localSettings.Values[property], typeof(T));
+            }
+            catch (InvalidCastException)
+            {
+                return default(T);
+            }
+        }
+    }
+}