public ReaderStatus ReadToObject <TObject>(ReaderState state,
ILookupNode <char, ReaderCallback <ReaderState, string, char, TObject> > root, ref TObject target)
{
if (state.Current == -1)
{
return(ReaderStatus.Succeeded);
}
while (true)
{
// Parse field name
var empty = true;
// FIXME: handle % encoding in field names
var node = root;
while (QueryStringCharacter.IsUnreserved(state.Current))
{
empty = false;
node = node.Follow((char)state.Current);
state.Pull();
}
if (empty)
{
state.Error("empty field name");
return(ReaderStatus.Failed);
}
// Parse field value
switch (state.Current)
{
case '=':
state.Pull();
state.Location = QueryStringLocation.ValueBegin;
if (!(node.HasValue ? node.Value(this, state, ref target) == ReaderStatus.Succeeded : this.ReadToValue(state, out _) == ReaderStatus.Succeeded))
{
return(ReaderStatus.Failed);
}
break;
default:
state.Location = QueryStringLocation.ValueEnd;
if (node.HasValue && node.Value(this, state, ref target) != ReaderStatus.Succeeded)
{
return(ReaderStatus.Failed);
}
break;
}
if (state.Location != QueryStringLocation.ValueEnd)
{
throw new InvalidOperationException(
"internal error, please report an issue on GitHub: https://github.com/r3c/verse/issues");
}
// Expect either field separator or end of stream
if (state.Current == -1)
{
return(ReaderStatus.Succeeded);
}
if (!QueryStringCharacter.IsSeparator(state.Current))
{
state.Error("unexpected character");
return(ReaderStatus.Failed);
}
state.Pull();
// Check for end of stream (in case of dangling separator e.g. "?k&") and resume loop
if (state.Current == -1)
{
return(ReaderStatus.Succeeded);
}
state.Location = QueryStringLocation.Sequence;
}
}
private static bool ReadValue(ReaderState state, out string value)
{
var buffer = new byte[state.Encoding.GetMaxByteCount(1)];
var builder = new StringBuilder(32);
while (true)
{
int current = state.Current;
if (QueryStringCharacter.IsUnreserved(current))
{
builder.Append((char)current);
state.Pull();
}
else if (current == '+')
{
builder.Append(' ');
state.Pull();
}
else if (current == '%')
{
int count;
for (count = 0; state.Current == '%'; ++count)
{
if (count >= buffer.Length)
{
value = default;
return(false);
}
state.Pull();
if (state.Current == -1)
{
value = default;
return(false);
}
var hex1 = QueryStringCharacter.HexaToDecimal(state.Current);
state.Pull();
if (state.Current == -1)
{
value = default;
return(false);
}
var hex2 = QueryStringCharacter.HexaToDecimal(state.Current);
state.Pull();
if (hex1 < 0 || hex2 < 0)
{
value = default;
return(false);
}
buffer[count] = (byte)((hex1 << 4) + hex2);
}
builder.Append(state.Encoding.GetChars(buffer, 0, count));
}
else
{
state.Location = QueryStringLocation.ValueEnd;
value = builder.ToString();
return(true);
}
}
}