private static HashSet <UInt128> Parse128BitHashes(CosmosObject hashDictionary, string propertyName)
{
HashSet <UInt128> hashSet = new HashSet <UInt128>();
if (!hashDictionary.TryGetValue(propertyName, out CosmosArray array))
{
throw new MalformedContinuationTokenException(
$"{nameof(UnorderdDistinctMap)} continuation token was malformed.");
}
foreach (CosmosElement item in array)
{
if (!(item is CosmosBinary binary))
{
throw new MalformedContinuationTokenException(
$"{nameof(UnorderdDistinctMap)} continuation token was malformed.");
}
// Todo have this method work with span<byte> instead to avoid the allocation.
UInt128 uint128 = UInt128.FromByteArray(binary.Value.ToArray());
hashSet.Add(uint128);
}
return(hashSet);
}
/// <summary>
/// Adds a string to the distinct map.
/// </summary>
/// <param name="value">The string to add.</param>
/// <returns>Whether or not the value was successfully added.</returns>
private bool AddStringValue(string value)
{
bool added = false;
int utf8Length = Encoding.UTF8.GetByteCount(value);
// If you fit the string with full fidelity in 24 bytes, then you might as well just hash the string.
if (utf8Length <= UnorderdDistinctMap.UInt192Length)
{
// Zero out the array since you want all trailing bytes to be 0 for the conversions that happen next.
Array.Clear(this.utf8Buffer, 0, this.utf8Buffer.Length);
Encoding.UTF8.GetBytes(value, 0, utf8Length, this.utf8Buffer, 0);
if (utf8Length == 0)
{
added = this.AddSimpleValue(SimpleValues.EmptyString);
}
else if (utf8Length <= UnorderdDistinctMap.UIntLength)
{
uint uintValue = BitConverter.ToUInt32(this.utf8Buffer, 0);
added = this.stringsLength4.Add(uintValue);
}
else if (utf8Length <= UnorderdDistinctMap.ULongLength)
{
ulong uLongValue = BitConverter.ToUInt64(this.utf8Buffer, 0);
added = this.stringLength8.Add(uLongValue);
}
else if (utf8Length <= UnorderdDistinctMap.UInt128Length)
{
UInt128 uInt128Value = UInt128.FromByteArray(this.utf8Buffer, 0);
added = this.stringLength16.Add(uInt128Value);
}
else
{
UInt192 uInt192Value = UInt192.FromByteArray(this.utf8Buffer, 0);
added = this.stringLength24.Add(uInt192Value);
}
}
else
{
// Else the string is too large and we will just store the hash.
UInt192 uint192Value = DistinctMap.GetHash(CosmosString.Create(value));
added = this.stringLength24Plus.Add(uint192Value);
}
return(added);
}
/// <summary>
/// Adds a string to the distinct map.
/// </summary>
/// <param name="value">The string to add.</param>
/// <returns>Whether or not the value was successfully added.</returns>
private bool AddStringValue(string value)
{
bool added = false;
int utf8Length = Encoding.UTF8.GetByteCount(value);
// If you can fit the string with full fidelity in 16 bytes, then you might as well just hash the string itself.
if (utf8Length <= UnorderdDistinctMap.UInt128Length)
{
Span <byte> utf8Buffer = stackalloc byte[UInt128Length];
Encoding.UTF8.GetBytes(value, utf8Buffer);
if (utf8Length == 0)
{
added = this.AddSimpleValue(SimpleValues.EmptyString);
}
else if (utf8Length <= UnorderdDistinctMap.UIntLength)
{
uint uintValue = MemoryMarshal.Read <uint>(utf8Buffer);
added = this.stringsLength4.Add(uintValue);
}
else if (utf8Length <= UnorderdDistinctMap.ULongLength)
{
ulong uLongValue = MemoryMarshal.Read <ulong>(utf8Buffer);
added = this.stringsLength8.Add(uLongValue);
}
else
{
UInt128 uInt128Value = UInt128.FromByteArray(utf8Buffer);
added = this.stringsLength16.Add(uInt128Value);
}
}
else
{
// Else the string is too large and we will just store the hash.
UInt128 uint128Value = DistinctHash.GetHash(CosmosString.Create(value));
added = this.stringsLength16Plus.Add(uint128Value);
}
return(added);
}
