/// <summary>Remove an entity from the index</summary>
/// <param name="trans">Transaction to use</param>
/// <param name="id">Id of the entity that has been deleted</param>
/// <param name="value">Previous value of the entity in the index</param>
public async Task <bool> RemoveAsync(IFdbTransaction trans, long id, TValue value)
{
if (trans == null)
{
throw new ArgumentNullException(nameof(trans));
}
var key = this.Subspace[value];
var data = await trans.GetAsync(key).ConfigureAwait(false);
if (data.HasValue)
{
var builder = new CompressedBitmapBuilder(MutableSlice.AsUnsafeMutableSlice(data));
builder.Clear((int)id); //BUGBUG: 64 bit id!
trans.Set(key, builder.ToSlice());
return(true);
}
return(false);
}
/// <summary>Returns a list of ids matching a specific value</summary>
/// <param name="trans"></param>
/// <param name="value">Value to lookup</param>
/// <param name="reverse"></param>
/// <returns>List of document ids matching this value for this particular index (can be empty if no document matches)</returns>
public async Task <IEnumerable <long>?> LookupAsync(IFdbReadOnlyTransaction trans, TValue value, bool reverse = false)
{
var key = this.Subspace[value];
var data = await trans.GetAsync(key).ConfigureAwait(false);
if (data.IsNull)
{
return(null);
}
if (data.IsEmpty)
{
return(Enumerable.Empty <long>());
}
var bitmap = new CompressedBitmap(MutableSlice.AsUnsafeMutableSlice(data));
if (reverse)
{
throw new NotImplementedException(); //TODO: GetView(reverse:true) !
}
return(bitmap.GetView().Select(x => (long)x /*BUGBUG 64 bits*/));
}
/// <summary>Update the indexed values of an entity</summary>
/// <param name="trans">Transaction to use</param>
/// <param name="id">Id of the entity that has changed</param>
/// <param name="newValue">Previous value of this entity in the index</param>
/// <param name="previousValue">New value of this entity in the index</param>
/// <returns>True if a change was performed in the index; otherwise false (if <paramref name="previousValue"/> and <paramref name="newValue"/>)</returns>
/// <remarks>If <paramref name="newValue"/> and <paramref name="previousValue"/> are identical, then nothing will be done. Otherwise, the old index value will be deleted and the new value will be added</remarks>
public async Task <bool> UpdateAsync(IFdbTransaction trans, long id, TValue newValue, TValue previousValue)
{
if (trans == null)
{
throw new ArgumentNullException(nameof(trans));
}
if (!this.ValueComparer.Equals(newValue, previousValue))
{
// remove previous value
if (this.IndexNullValues || previousValue != null)
{
var key = this.Subspace[previousValue];
var data = await trans.GetAsync(key).ConfigureAwait(false);
if (data.HasValue)
{
var builder = new CompressedBitmapBuilder(MutableSlice.AsUnsafeMutableSlice(data));
builder.Clear((int)id); //BUGBUG: 64 bit id!
trans.Set(key, builder.ToSlice());
}
}
// add new value
if (this.IndexNullValues || newValue != null)
{
var key = this.Subspace[newValue];
var data = await trans.GetAsync(key).ConfigureAwait(false);
var builder = data.HasValue ? new CompressedBitmapBuilder(MutableSlice.AsUnsafeMutableSlice(data)) : CompressedBitmapBuilder.Empty;
builder.Set((int)id); //BUGBUG: 64 bit id!
trans.Set(key, builder.ToSlice());
}
// cannot be both null, so we did at least something)
return(true);
}
return(false);
}
/// <summary>Insert a newly created entity to the index</summary>
/// <param name="trans">Transaction to use</param>
/// <param name="id">Id of the new entity (that was never indexed before)</param>
/// <param name="value">Value of this entity in the index</param>
/// <returns>True if a value was inserted into the index; or false if <paramref name="value"/> is null and <see cref="IndexNullValues"/> is false, or if this <paramref name="id"/> was already indexed at this <paramref name="value"/>.</returns>
public async Task <bool> AddAsync(IFdbTransaction trans, long id, TValue value)
{
if (trans == null)
{
throw new ArgumentNullException(nameof(trans));
}
if (this.IndexNullValues || value != null)
{
var key = this.Subspace[value];
var data = await trans.GetAsync(key).ConfigureAwait(false);
var builder = data.HasValue ? new CompressedBitmapBuilder(MutableSlice.AsUnsafeMutableSlice(data)) : CompressedBitmapBuilder.Empty;
//TODO: wasteful to crate a builder to only set on bit ?
builder.Set((int)id); //BUGBUG: id should be 64-bit!
//TODO: if bit was already set, skip the set ?
trans.Set(key, builder.ToSlice());
return(true);
}
return(false);
}
