/// <summary>
/// Initialize with a span buffer
/// </summary>
/// <param name="buffer"></param>
/// <param name="t"></param>
public XL20(Span <byte> buffer, Type t)
{
var header = MemoryMarshal.Read <XLHeader>(buffer);
if (header.Magic != ((uint)DataType.XL & 0xFFFF) && header.Version != 0x14)
{
throw new InvalidOperationException("Not an XL stream");
}
UnderlyingType = t;
var offset = (int)header.TableOffset;
var properties = t.GetProperties();
for (var i = 0; i < header.FileSize; i++)
{
var instance = Activator.CreateInstance(t);
var localOffset = 0;
var slice = buffer.Slice(offset);
foreach (var property in properties)
{
var type = property.PropertyType;
object?value;
switch (type.FullName)
{
case "System.Int64":
value = SpanHelper.ReadLittleLong(slice, ref localOffset);
break;
case "System.Int32":
value = SpanHelper.ReadLittleInt(slice, ref localOffset);
break;
case "System.Int16":
value = SpanHelper.ReadLittleShort(slice, ref localOffset);
break;
case "System.UInt64":
value = SpanHelper.ReadLittleULong(slice, ref localOffset);
break;
case "System.UInt32":
value = SpanHelper.ReadLittleUInt(slice, ref localOffset);
break;
case "System.UInt16":
value = SpanHelper.ReadLittleUShort(slice, ref localOffset);
break;
case "System.Int8":
case "System.SByte":
value = SpanHelper.ReadSByte(slice, ref localOffset);
break;
case "System.UInt8":
case "System.Byte":
value = SpanHelper.ReadByte(slice, ref localOffset);
break;
case "System.Single":
value = SpanHelper.ReadLittleSingle(slice, ref localOffset);
break;
case "System.Double":
value = SpanHelper.ReadLittleDouble(slice, ref localOffset);
break;
case "System.Decimal":
value = SpanHelper.ReadLittleDecimal(slice, ref localOffset);
break;
case "System.Boolean":
value = SpanHelper.ReadByte(slice, ref localOffset) == 1;
break;
case "System.String":
{
var stringSize = property.GetCustomAttribute <StringLengthAttribute>();
var size = stringSize?.MaximumLength ?? SpanHelper.ReadLittleInt(slice, ref localOffset);
value = size > 0 ? Encoding.UTF8.GetString(slice.Slice(localOffset, size)) : null;
if (stringSize != null && value is string stringValue)
{
value = stringValue.TrimEnd('\u0000');
}
localOffset += size;
break;
}
default:
throw new NotImplementedException(type.FullName);
}
property.SetValue(instance, value);
}
Entries.Add(instance);
offset += localOffset;
}
}
