/// <summary>
/// Removes a selection of items that inherit from ICollectable object from their database collection.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="items"></param>
public void Remove <T>(ICollection <T> items) where T : ICollectableObject
{
if (items.IsNull())
{
throw new ArgumentNullException("The parameter items cannot be null.");
}
DatabaseItemInfo <T> dbInfo = GetDatabaseItemInfo <T>();
var db = GetType().GetMethod("GetDatabase", BindingFlags.NonPublic | BindingFlags.Instance).MakeGenericMethod(dbInfo.DatabaseType).Invoke(this, null);
var dbCollection = db.GetType().GetProperty(dbInfo.CollectionName).GetValue(db) as ICollection <T>;
List <T> newCollection = dbCollection.IsNull() ? new List <T>() : dbCollection.ToList();
items.ForEach(item => newCollection.RemoveAll(i => ((ICollectableObject)i).GUID == item.GUID));
Save <T>(newCollection);
}
/// <summary>
/// Gets a selection of items that inherit from ICollectable object from their database collection.
/// If propertyName and propertyValue are null, then returns all items of the selected type T in the database.
/// If propertyName and propertyValue are NOT null, then all items matching the query (propertyNames that have propertyValues as their value).
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="propertyName"></param>
/// <param name="propertyValue"></param>
/// <returns></returns>
private ICollection <T> Get <T>(string propertyName = null, object propertyValue = null, bool dummyParameter = false) where T : ICollectableObject
{
if (string.IsNullOrEmpty(propertyName) && !propertyValue.IsNull())
{
throw new Exception("If propertyName is null, then propertyValue must also be null.");
}
bool getAllItems = string.IsNullOrEmpty(propertyName) && propertyValue.IsNull();
DatabaseItemInfo <T> dbInfo = GetDatabaseItemInfo <T>();
var db = GetType().GetMethod("GetDatabase", BindingFlags.NonPublic | BindingFlags.Instance).MakeGenericMethod(dbInfo.DatabaseType).Invoke(this, null);
var dbCollection = db.GetType().GetProperty(dbInfo.CollectionName).GetValue(db) as ICollection <T>;
ICollection <T> items = null;
if (getAllItems)
{
items = dbCollection;
}
else
{
List <T> col = new List <T>();
foreach (var item in dbCollection)
{
var prop = item.GetType().GetProperty(propertyName);
if (!prop.IsNull())
{
var propValue = prop.GetValue(item);
if (!propValue.IsNull())
{
if (prop.GetValue(item).ToString() == (propertyValue ?? "").ToString())
{
col.Add(item);
}
}
}
}
items = col.Any() ? col : null;
}
//A collection or null should be returned.
return(items);
}
/// <summary>
/// Saves a selection of items in its respective database.
/// </summary>
/// <typeparam name="T"></typeparam>
/// <param name="items"></param>
public void Save <T>(ICollection <T> items) where T : ICollectableObject
{
if (items.IsNull())
{
throw new ArgumentNullException("The parameter items cannot be null.");
}
DatabaseItemInfo <T> dbInfo = GetDatabaseItemInfo <T>();
var db = GetType().GetMethod("GetDatabase", BindingFlags.NonPublic | BindingFlags.Instance).MakeGenericMethod(dbInfo.DatabaseType).Invoke(this, null);
Type typeOfCollection = db.GetType().GetProperty(dbInfo.CollectionName).PropertyType;
object newItems = EnumerateCollection <T>(items);
if (typeOfCollection.BaseType == typeof(Array))
{
newItems = (newItems as ICollection <T>).ToArray();
}
else if (typeOfCollection.BaseType == typeof(Collection <T>))
{
newItems = (newItems as ICollection <T>).ToObservableCollection();
}
db.GetType().GetProperty(dbInfo.CollectionName).SetValue(db, newItems);
string path = GetDatabasePath(dbInfo.DatabaseType);
lock (lockObject)
{
var xml = db.Serialize();
try
{
try
{
if (!mutex.IsNull())
{
mutex.WaitOne();
}
xml.Save(path);
//Will fire the database changed event when the FileSystemWatcher is unavailable.
//This should happen only when using Xamarin.Forms as there is no native support for that class.
if (fileSystemWatcher.IsNull())
{
OnDatabaseChanged?.Invoke(this, new OnDatabaseChangedEventArgs(dbInfo.DatabaseType.Name, DateTime.Now));
}
}
catch
{
throw;
}
finally
{
if (!mutex.IsNull())
{
mutex.ReleaseMutex();
}
}
}
catch
{
throw;
}
finally
{
}
}
}
