Minecraft-Console-Client/MinecraftClient/Json.cs
2022-10-20 19:29:35 +02:00

280 lines
12 KiB
C#

using System;
using System.Collections.Generic;
using System.Text;
namespace MinecraftClient
{
/// <summary>
/// This class parses JSON data and returns an object describing that data.
/// Really lightweight JSON handling by ORelio - (c) 2013 - 2020
/// </summary>
public static class Json
{
/// <summary>
/// Parse some JSON and return the corresponding JSON object
/// </summary>
public static JSONData ParseJson(string json)
{
int cursorpos = 0;
return String2Data(json, ref cursorpos);
}
/// <summary>
/// The class storing unserialized JSON data
/// The data can be an object, an array or a string
/// </summary>
public class JSONData
{
public enum DataType { Object, Array, String };
private readonly DataType type;
public DataType Type { get { return type; } }
public Dictionary<string, JSONData> Properties;
public List<JSONData> DataArray;
public string StringValue;
public JSONData(DataType datatype)
{
type = datatype;
Properties = new Dictionary<string, JSONData>();
DataArray = new List<JSONData>();
StringValue = String.Empty;
}
}
/// <summary>
/// Parse a JSON string to build a JSON object
/// </summary>
/// <param name="toparse">String to parse</param>
/// <param name="cursorpos">Cursor start (set to 0 for function init)</param>
private static JSONData String2Data(string toparse, ref int cursorpos)
{
try
{
JSONData data;
SkipSpaces(toparse, ref cursorpos);
switch (toparse[cursorpos])
{
//Object
case '{':
data = new JSONData(JSONData.DataType.Object);
cursorpos++;
SkipSpaces(toparse, ref cursorpos);
while (toparse[cursorpos] != '}')
{
if (toparse[cursorpos] == '"')
{
JSONData propertyname = String2Data(toparse, ref cursorpos);
if (toparse[cursorpos] == ':') { cursorpos++; } else { /* parse error ? */ }
JSONData propertyData = String2Data(toparse, ref cursorpos);
data.Properties[propertyname.StringValue] = propertyData;
}
else cursorpos++;
}
cursorpos++;
break;
//Array
case '[':
data = new JSONData(JSONData.DataType.Array);
cursorpos++;
SkipSpaces(toparse, ref cursorpos);
while (toparse[cursorpos] != ']')
{
if (toparse[cursorpos] == ',') { cursorpos++; }
JSONData arrayItem = String2Data(toparse, ref cursorpos);
data.DataArray.Add(arrayItem);
}
cursorpos++;
break;
//String
case '"':
data = new JSONData(JSONData.DataType.String);
cursorpos++;
while (toparse[cursorpos] != '"')
{
if (toparse[cursorpos] == '\\')
{
try //Unicode character \u0123
{
if (toparse[cursorpos + 1] == 'u'
&& IsHex(toparse[cursorpos + 2])
&& IsHex(toparse[cursorpos + 3])
&& IsHex(toparse[cursorpos + 4])
&& IsHex(toparse[cursorpos + 5]))
{
//"abc\u0123abc" => "0123" => 0123 => Unicode char n°0123 => Add char to string
data.StringValue += char.ConvertFromUtf32(int.Parse(toparse.Substring(cursorpos + 2, 4),
System.Globalization.NumberStyles.HexNumber));
cursorpos += 6; continue;
}
else if (toparse[cursorpos + 1] == 'n')
{
data.StringValue += '\n';
cursorpos += 2;
continue;
}
else if (toparse[cursorpos + 1] == 'r')
{
data.StringValue += '\r';
cursorpos += 2;
continue;
}
else if (toparse[cursorpos + 1] == 't')
{
data.StringValue += '\t';
cursorpos += 2;
continue;
}
else cursorpos++; //Normal character escapement \"
}
catch (IndexOutOfRangeException) { cursorpos++; } // \u01<end of string>
catch (ArgumentOutOfRangeException) { cursorpos++; } // Unicode index 0123 was invalid
}
data.StringValue += toparse[cursorpos];
cursorpos++;
}
cursorpos++;
break;
//Number
case '0':
case '1':
case '2':
case '3':
case '4':
case '5':
case '6':
case '7':
case '8':
case '9':
case '.':
case '-':
data = new JSONData(JSONData.DataType.String);
StringBuilder sb = new();
while ((toparse[cursorpos] >= '0' && toparse[cursorpos] <= '9') || toparse[cursorpos] == '.' || toparse[cursorpos] == '-')
{
sb.Append(toparse[cursorpos]);
cursorpos++;
}
data.StringValue = sb.ToString();
break;
//Boolean : true
case 't':
data = new JSONData(JSONData.DataType.String);
cursorpos++;
if (toparse[cursorpos] == 'r') { cursorpos++; }
if (toparse[cursorpos] == 'u') { cursorpos++; }
if (toparse[cursorpos] == 'e') { cursorpos++; data.StringValue = "true"; }
break;
//Boolean : false
case 'f':
data = new JSONData(JSONData.DataType.String);
cursorpos++;
if (toparse[cursorpos] == 'a') { cursorpos++; }
if (toparse[cursorpos] == 'l') { cursorpos++; }
if (toparse[cursorpos] == 's') { cursorpos++; }
if (toparse[cursorpos] == 'e') { cursorpos++; data.StringValue = "false"; }
break;
//Null field
case 'n':
data = new JSONData(JSONData.DataType.String);
cursorpos++;
if (toparse[cursorpos] == 'u') { cursorpos++; }
if (toparse[cursorpos] == 'l') { cursorpos++; }
if (toparse[cursorpos] == 'l') { cursorpos++; data.StringValue = "null"; }
break;
//Unknown data
default:
cursorpos++;
return String2Data(toparse, ref cursorpos);
}
SkipSpaces(toparse, ref cursorpos);
return data;
}
catch (IndexOutOfRangeException)
{
return new JSONData(JSONData.DataType.String);
}
}
/// <summary>
/// Check if a char is an hexadecimal char (0-9 A-F a-f)
/// </summary>
/// <param name="c">Char to test</param>
/// <returns>True if hexadecimal</returns>
private static bool IsHex(char c) { return ((c >= '0' && c <= '9') || (c >= 'A' && c <= 'F') || (c >= 'a' && c <= 'f')); }
/// <summary>
/// Advance the cursor to skip white spaces and line breaks
/// </summary>
/// <param name="toparse">String to parse</param>
/// <param name="cursorpos">Cursor position to update</param>
private static void SkipSpaces(string toparse, ref int cursorpos)
{
while (cursorpos < toparse.Length
&& (char.IsWhiteSpace(toparse[cursorpos])
|| toparse[cursorpos] == '\r'
|| toparse[cursorpos] == '\n'))
cursorpos++;
}
// Original: https://github.com/mono/mono/blob/master/mcs/class/System.Json/System.Json/JsonValue.cs
private static bool NeedEscape(string src, int i)
{
char c = src[i];
return c < 32 || c == '"' || c == '\\'
// Broken lead surrogate
|| (c >= '\uD800' && c <= '\uDBFF' &&
(i == src.Length - 1 || src[i + 1] < '\uDC00' || src[i + 1] > '\uDFFF'))
// Broken tail surrogate
|| (c >= '\uDC00' && c <= '\uDFFF' &&
(i == 0 || src[i - 1] < '\uD800' || src[i - 1] > '\uDBFF'))
// To produce valid JavaScript
|| c == '\u2028' || c == '\u2029'
// Escape "</" for <script> tags
|| (c == '/' && i > 0 && src[i - 1] == '<');
}
public static string EscapeString(string src)
{
StringBuilder sb = new StringBuilder();
int start = 0;
for (int i = 0; i < src.Length; i++)
{
if (NeedEscape(src, i))
{
sb.Append(src, start, i - start);
switch (src[i])
{
case '\b': sb.Append("\\b"); break;
case '\f': sb.Append("\\f"); break;
case '\n': sb.Append("\\n"); break;
case '\r': sb.Append("\\r"); break;
case '\t': sb.Append("\\t"); break;
case '\"': sb.Append("\\\""); break;
case '\\': sb.Append("\\\\"); break;
case '/': sb.Append("\\/"); break;
default:
sb.Append("\\u");
sb.Append(((int)src[i]).ToString("x04"));
break;
}
start = i + 1;
}
}
sb.Append(src, start, src.Length - start);
return sb.ToString();
}
}
}