ViaVersion/api/src/main/java/us/myles/ViaVersion/api/minecraft/nbt/TagStringReader.java

315 lines
13 KiB
Java

/*
* This file is part of adventure, licensed under the MIT License.
*
* Copyright (c) 2017-2020 KyoriPowered
*
* Permission is hereby granted, free of charge, to any person obtaining a copy
* of this software and associated documentation files (the "Software"), to deal
* in the Software without restriction, including without limitation the rights
* to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
* copies of the Software, and to permit persons to whom the Software is
* furnished to do so, subject to the following conditions:
*
* The above copyright notice and this permission notice shall be included in all
* copies or substantial portions of the Software.
*
* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
* IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
* FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
* AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
* LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
* OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
* SOFTWARE.
*/
package us.myles.ViaVersion.api.minecraft.nbt;
import com.github.steveice10.opennbt.tag.builtin.ByteArrayTag;
import com.github.steveice10.opennbt.tag.builtin.ByteTag;
import com.github.steveice10.opennbt.tag.builtin.CompoundTag;
import com.github.steveice10.opennbt.tag.builtin.DoubleTag;
import com.github.steveice10.opennbt.tag.builtin.FloatTag;
import com.github.steveice10.opennbt.tag.builtin.IntArrayTag;
import com.github.steveice10.opennbt.tag.builtin.IntTag;
import com.github.steveice10.opennbt.tag.builtin.ListTag;
import com.github.steveice10.opennbt.tag.builtin.LongArrayTag;
import com.github.steveice10.opennbt.tag.builtin.LongTag;
import com.github.steveice10.opennbt.tag.builtin.NumberTag;
import com.github.steveice10.opennbt.tag.builtin.ShortTag;
import com.github.steveice10.opennbt.tag.builtin.StringTag;
import com.github.steveice10.opennbt.tag.builtin.Tag;
import java.util.ArrayList;
import java.util.List;
import java.util.stream.IntStream;
/**
* See https://github.com/KyoriPowered/adventure.
*/
/* package */ final class TagStringReader {
private final CharBuffer buffer;
public TagStringReader(final CharBuffer buffer) {
this.buffer = buffer;
}
public CompoundTag compound() throws StringTagParseException {
this.buffer.expect(Tokens.COMPOUND_BEGIN);
final CompoundTag compoundTag = new CompoundTag();
if (this.buffer.peek() == Tokens.COMPOUND_END) {
this.buffer.take();
return compoundTag;
}
while (this.buffer.hasMore()) {
final String key = this.key();
final Tag tag = this.tag();
compoundTag.put(key, tag);
if (this.separatorOrCompleteWith(Tokens.COMPOUND_END)) {
return compoundTag;
}
}
throw this.buffer.makeError("Unterminated compound tag!");
}
public ListTag list() throws StringTagParseException {
final ListTag listTag = new ListTag();
this.buffer.expect(Tokens.ARRAY_BEGIN);
final boolean prefixedIndex = this.buffer.peek() == '0' && this.buffer.peek(1) == ':';
while (this.buffer.hasMore()) {
if (this.buffer.peek() == Tokens.ARRAY_END) {
this.buffer.advance();
return listTag;
}
if (prefixedIndex) {
this.buffer.takeUntil(':');
}
final Tag next = this.tag();
// TODO: validate type
listTag.add(next);
if (this.separatorOrCompleteWith(Tokens.ARRAY_END)) {
return listTag;
}
}
throw this.buffer.makeError("Reached end of file without end of list tag!");
}
/**
* Similar to a list tag in syntax, but returning a single array tag rather than a list of tags.
*
* @return array-typed tag
*/
public Tag array(final char elementType) throws StringTagParseException {
this.buffer.expect(Tokens.ARRAY_BEGIN)
.expect(elementType)
.expect(Tokens.ARRAY_SIGNATURE_SEPARATOR);
if (elementType == Tokens.TYPE_BYTE) {
return new ByteArrayTag(this.byteArray());
} else if (elementType == Tokens.TYPE_INT) {
return new IntArrayTag(this.intArray());
} else if (elementType == Tokens.TYPE_LONG) {
return new LongArrayTag(this.longArray());
} else {
throw this.buffer.makeError("Type " + elementType + " is not a valid element type in an array!");
}
}
private byte[] byteArray() throws StringTagParseException {
final List<Byte> bytes = new ArrayList<>();
while (this.buffer.hasMore()) {
final CharSequence value = this.buffer.skipWhitespace().takeUntil(Tokens.TYPE_BYTE);
try {
bytes.add(Byte.valueOf(value.toString()));
} catch (final NumberFormatException ex) {
throw this.buffer.makeError("All elements of a byte array must be bytes!");
}
if (this.separatorOrCompleteWith(Tokens.ARRAY_END)) {
final byte[] result = new byte[bytes.size()];
for (int i = 0; i < bytes.size(); ++i) { // todo yikes, let's do less boxing
result[i] = bytes.get(i);
}
return result;
}
}
throw this.buffer.makeError("Reached end of document without array close");
}
private int[] intArray() throws StringTagParseException {
final IntStream.Builder builder = IntStream.builder();
while (this.buffer.hasMore()) {
final Tag value = this.tag();
if (!(value instanceof IntTag)) {
throw this.buffer.makeError("All elements of an int array must be ints!");
}
builder.add(((NumberTag) value).asInt());
if (this.separatorOrCompleteWith(Tokens.ARRAY_END)) {
return builder.build().toArray();
}
}
throw this.buffer.makeError("Reached end of document without array close");
}
private long[] longArray() throws StringTagParseException {
final List<Long> longs = new ArrayList<>();
while (this.buffer.hasMore()) {
final CharSequence value = this.buffer.skipWhitespace().takeUntil(Tokens.TYPE_LONG);
try {
longs.add(Long.valueOf(value.toString()));
} catch (final NumberFormatException ex) {
throw this.buffer.makeError("All elements of a long array must be longs!");
}
if (this.separatorOrCompleteWith(Tokens.ARRAY_END)) {
final long[] result = new long[longs.size()];
for (int i = 0; i < longs.size(); ++i) { // todo yikes
result[i] = longs.get(i);
}
return result;
}
}
throw this.buffer.makeError("Reached end of document without array close");
}
public String key() throws StringTagParseException {
this.buffer.skipWhitespace();
final char starChar = this.buffer.peek();
try {
if (starChar == Tokens.SINGLE_QUOTE || starChar == Tokens.DOUBLE_QUOTE) {
return unescape(this.buffer.takeUntil(this.buffer.take()).toString());
}
final StringBuilder builder = new StringBuilder();
while (this.buffer.peek() != ':') { // DO NOT CHECK FOR CHARACTER VALIDITY; LEGACY NBT ALLOWS ANY CHARACTER, EVEN WHEN UNQUOTED
builder.append(this.buffer.take());
}
return builder.toString();
} finally {
this.buffer.expect(Tokens.COMPOUND_KEY_TERMINATOR);
}
}
public Tag tag() throws StringTagParseException {
final char startToken = this.buffer.skipWhitespace().peek();
switch (startToken) {
case Tokens.COMPOUND_BEGIN:
return this.compound();
case Tokens.ARRAY_BEGIN:
if (this.buffer.peek(2) == ';') { // we know we're an array tag
return this.array(this.buffer.peek(1));
} else {
return this.list();
}
case Tokens.SINGLE_QUOTE:
case Tokens.DOUBLE_QUOTE:
// definitely a string tag
this.buffer.advance();
return new StringTag(unescape(this.buffer.takeUntil(startToken).toString()));
default: // scalar
return this.scalar();
}
}
/**
* A tag that is definitely some sort of scalar
*
* <p>Does not detect quoted strings, so </p>
*
* @return a parsed tag
*/
private Tag scalar() {
final StringBuilder builder = new StringBuilder();
boolean possiblyNumeric = true;
while (this.buffer.hasMore()) {
final char current = this.buffer.peek();
if (possiblyNumeric && !Tokens.numeric(current)) {
if (builder.length() != 0) {
Tag result = null;
try {
switch (Character.toUpperCase(current)) { // try to read and return as a number
// case Tokens.TYPE_INTEGER: // handled below, ints are ~special~
case Tokens.TYPE_BYTE:
result = new ByteTag(Byte.parseByte(builder.toString()));
break;
case Tokens.TYPE_SHORT:
result = new ShortTag(Short.parseShort(builder.toString()));
break;
case Tokens.TYPE_LONG:
result = new LongTag(Long.parseLong(builder.toString()));
break;
case Tokens.TYPE_FLOAT:
result = new FloatTag(Float.parseFloat(builder.toString()));
break;
case Tokens.TYPE_DOUBLE:
result = new DoubleTag(Double.parseDouble(builder.toString()));
break;
}
} catch (final NumberFormatException ex) {
possiblyNumeric = false; // fallback to treating as a String
}
if (result != null) {
this.buffer.take();
return result;
}
}
}
if (current == '\\') { // escape -- we are significantly more lenient than original format at the moment
this.buffer.advance();
builder.append(this.buffer.take());
} else if (Tokens.id(current)) {
builder.append(this.buffer.take());
} else { // end of value
break;
}
}
// if we run out of content without an explicit value separator, then we're either an integer or string tag -- all others have a character at the end
final String built = builder.toString();
if (possiblyNumeric) {
try {
return new IntTag(Integer.parseInt(built));
} catch (final NumberFormatException ex) {
// ignore
}
}
return new StringTag(built);
}
private boolean separatorOrCompleteWith(final char endCharacter) throws StringTagParseException {
if (this.buffer.skipWhitespace().peek() == endCharacter) {
this.buffer.take();
return true;
}
this.buffer.expect(Tokens.VALUE_SEPARATOR);
if (this.buffer.skipWhitespace().peek() == endCharacter) {
this.buffer.take();
return true;
}
return false;
}
/**
* Remove simple escape sequences from a string
*
* @param withEscapes input string with escapes
* @return string with escapes processed
*/
private static String unescape(final String withEscapes) {
int escapeIdx = withEscapes.indexOf(Tokens.ESCAPE_MARKER);
if (escapeIdx == -1) { // nothing to unescape
return withEscapes;
}
int lastEscape = 0;
final StringBuilder output = new StringBuilder(withEscapes.length());
do {
output.append(withEscapes, lastEscape, escapeIdx);
lastEscape = escapeIdx + 1;
} while ((escapeIdx = withEscapes.indexOf(Tokens.ESCAPE_MARKER, lastEscape + 1)) != -1); // add one extra character to make sure we don't include escaped backslashes
output.append(withEscapes.substring(lastEscape));
return output.toString();
}
}