private object? ReadStringValue()

in src/Elastic.Apm/Libraries/Newtonsoft.Json/JsonTextReader.cs [543:662]
112 lines of code
50 McCabe index (conditional complexity)

		private object? ReadStringValue(ReadType readType)
		{
			EnsureBuffer();
			MiscellaneousUtils.Assert(CharBuffer != null);

			switch (_currentState)
			{
				case State.PostValue:
					if (ParsePostValue(true)) return null;

					goto case State.Start;
				case State.Start:
				case State.Property:
				case State.Array:
				case State.ArrayStart:
				case State.Constructor:
				case State.ConstructorStart:
					while (true)
					{
						var currentChar = CharBuffer[CharPos];

						switch (currentChar)
						{
							case '\0':
								if (ReadNullChar())
								{
									SetToken(JsonToken.None, null, false);
									return null;
								}
								break;
							case '"':
							case '\'':
								ParseString(currentChar, readType);
								return FinishReadQuotedStringValue(readType);
							case '-':
								if (EnsureChars(1, true) && CharBuffer[CharPos + 1] == 'I')
									return ParseNumberNegativeInfinity(readType);
								else
								{
									ParseNumber(readType);
									return Value;
								}
							case '.':
							case '0':
							case '1':
							case '2':
							case '3':
							case '4':
							case '5':
							case '6':
							case '7':
							case '8':
							case '9':
								if (readType != ReadType.ReadAsString)
								{
									CharPos++;
									throw CreateUnexpectedCharacterException(currentChar);
								}
								ParseNumber(ReadType.ReadAsString);
								return Value;
							case 't':
							case 'f':
								if (readType != ReadType.ReadAsString)
								{
									CharPos++;
									throw CreateUnexpectedCharacterException(currentChar);
								}
								var expected = currentChar == 't' ? JsonConvert.True : JsonConvert.False;
								if (!MatchValueWithTrailingSeparator(expected)) throw CreateUnexpectedCharacterException(CharBuffer[CharPos]);

								SetToken(JsonToken.String, expected);
								return expected;
							case 'I':
								return ParseNumberPositiveInfinity(readType);
							case 'N':
								return ParseNumberNaN(readType);
							case 'n':
								HandleNull();
								return null;
							case '/':
								ParseComment(false);
								break;
							case ',':
								ProcessValueComma();
								break;
							case ']':
								CharPos++;
								if (_currentState == State.Array || _currentState == State.ArrayStart || _currentState == State.PostValue)
								{
									SetToken(JsonToken.EndArray);
									return null;
								}
								throw CreateUnexpectedCharacterException(currentChar);
							case StringUtils.CarriageReturn:
								ProcessCarriageReturn(false);
								break;
							case StringUtils.LineFeed:
								ProcessLineFeed();
								break;
							case ' ':
							case StringUtils.Tab:
								// eat
								CharPos++;
								break;
							default:
								CharPos++;

								if (!char.IsWhiteSpace(currentChar)) throw CreateUnexpectedCharacterException(currentChar);

								// eat
								break;
						}
					}
				case State.Finished:
					ReadFinished();
					return null;
				default:
					throw JsonReaderException.Create(this, "Unexpected state: {0}.".FormatWith(CultureInfo.InvariantCulture, CurrentState));
			}
		}