SHiNE-server/SHiNE-server/shine-server-blockchain/src/main/java/blockchain/body/TextReplyBody.java

252 lines
9.3 KiB
Java

package blockchain.body;
import blockchain.MsgSubType;
import java.nio.ByteBuffer;
import java.nio.ByteOrder;
import java.nio.charset.CharacterCodingException;
import java.nio.charset.CodingErrorAction;
import java.nio.charset.StandardCharsets;
import java.util.Arrays;
import java.util.Objects;
/**
* TextReplyBody — type=1, ver=1.
*
* subType:
* - REPLY (20)
* - EDIT_REPLY (21)
*
* Форматы bodyBytes (BigEndian):
*
* REPLY:
* [1] toBlockchainNameLen (uint8)
* [N] toBlockchainName UTF-8
* [4] toBlockGlobalNumber
* [32] toBlockHash32
* [2] textLenBytes (uint16)
* [M] text UTF-8
*
* EDIT_REPLY:
* [4] toBlockGlobalNumber
* [32] toBlockHash32
* [2] textLenBytes (uint16)
* [N] text UTF-8
*/
public final class TextReplyBody implements BodyRecord, BodyHasTarget {
public static final short TYPE = 1;
public static final short VER = 1;
public static final int KEY = ((TYPE & 0xFFFF) << 16) | (VER & 0xFFFF);
public final short subType; // из header
public final short version; // (=1)
// target
public final String toBlockchainName; // nullable для EDIT_REPLY
public final int toBlockGlobalNumber;
public final byte[] toBlockHash32; // 32
// text
public final String message;
public TextReplyBody(short subType, short version, byte[] bodyBytes) {
Objects.requireNonNull(bodyBytes, "bodyBytes == null");
this.subType = subType;
this.version = version;
if ((this.version & 0xFFFF) != (VER & 0xFFFF)) {
throw new IllegalArgumentException("TextReplyBody version must be 1, got=" + (this.version & 0xFFFF));
}
int st = this.subType & 0xFFFF;
if (st != (MsgSubType.TEXT_REPLY & 0xFFFF) && st != (MsgSubType.TEXT_EDIT_REPLY & 0xFFFF)) {
throw new IllegalArgumentException("TextReplyBody supports only REPLY/EDIT_REPLY, got subType=" + st);
}
ByteBuffer bb = ByteBuffer.wrap(bodyBytes).order(ByteOrder.BIG_ENDIAN);
if (st == (MsgSubType.TEXT_REPLY & 0xFFFF)) {
// минимум: nameLen[1]+name[1]+global[4]+hash[32]+textLen[2]
ensureMin(bb, 1 + 1 + 4 + 32 + 2, "REPLY too short");
int nameLen = Byte.toUnsignedInt(bb.get());
if (nameLen <= 0) throw new IllegalArgumentException("REPLY toBlockchainNameLen is 0");
ensureMin(bb, nameLen + 4 + 32 + 2, "REPLY payload too short");
byte[] nameBytes = new byte[nameLen];
bb.get(nameBytes);
this.toBlockchainName = new String(nameBytes, StandardCharsets.UTF_8);
this.toBlockGlobalNumber = bb.getInt();
this.toBlockHash32 = new byte[32];
bb.get(this.toBlockHash32);
} else {
// EDIT_REPLY: target без имени
ensureMin(bb, (4 + 32) + 2, "EDIT_REPLY too short");
this.toBlockchainName = null;
this.toBlockGlobalNumber = bb.getInt();
this.toBlockHash32 = new byte[32];
bb.get(this.toBlockHash32);
}
this.message = readStrictUtf8Len16(bb, "TextReplyBody text", st == (MsgSubType.TEXT_EDIT_REPLY & 0xFFFF));
ensureNoTail(bb, "TextReplyBody");
}
public TextReplyBody(short subType,
int toBlockGlobalNumber,
byte[] toBlockHash32,
String toBlockchainName,
String message) {
Objects.requireNonNull(message, "message == null");
Objects.requireNonNull(toBlockHash32, "toBlockHash32 == null");
int st = subType & 0xFFFF;
if (st != (MsgSubType.TEXT_REPLY & 0xFFFF) && st != (MsgSubType.TEXT_EDIT_REPLY & 0xFFFF)) {
throw new IllegalArgumentException("TextReplyBody supports only REPLY/EDIT_REPLY");
}
if (st == (MsgSubType.TEXT_REPLY & 0xFFFF) && message.isBlank()) {
throw new IllegalArgumentException("message is blank");
}
if (toBlockGlobalNumber < 0) throw new IllegalArgumentException("toBlockGlobalNumber < 0");
if (toBlockHash32.length != 32) throw new IllegalArgumentException("toBlockHash32 != 32");
if (st == (MsgSubType.TEXT_REPLY & 0xFFFF)) {
Objects.requireNonNull(toBlockchainName, "toBlockchainName == null");
if (toBlockchainName.isBlank()) throw new IllegalArgumentException("toBlockchainName is blank");
this.toBlockchainName = toBlockchainName;
} else {
// EDIT_REPLY: имя не хранить
this.toBlockchainName = null;
}
this.subType = subType;
this.version = VER;
this.toBlockGlobalNumber = toBlockGlobalNumber;
this.toBlockHash32 = Arrays.copyOf(toBlockHash32, 32);
this.message = message;
}
@Override
public TextReplyBody check() {
int st = subType & 0xFFFF;
if (st != (MsgSubType.TEXT_REPLY & 0xFFFF) && st != (MsgSubType.TEXT_EDIT_REPLY & 0xFFFF))
throw new IllegalArgumentException("Bad TextReplyBody subType: " + st);
if (toBlockGlobalNumber < 0)
throw new IllegalArgumentException("toBlockGlobalNumber < 0");
if (toBlockHash32 == null || toBlockHash32.length != 32)
throw new IllegalArgumentException("toBlockHash32 invalid");
if (st == (MsgSubType.TEXT_REPLY & 0xFFFF)) {
if (message == null || message.isBlank())
throw new IllegalArgumentException("Text message is blank");
if (toBlockchainName == null || toBlockchainName.isBlank())
throw new IllegalArgumentException("REPLY toBlockchainName is blank");
} else {
if (message == null) throw new IllegalArgumentException("EDIT_REPLY message is null");
if (toBlockchainName != null)
throw new IllegalArgumentException("EDIT_REPLY must not contain toBlockchainName");
}
return this;
}
@Override
public byte[] toBytes() {
byte[] msgUtf8 = message.getBytes(StandardCharsets.UTF_8);
if (msgUtf8.length > 65535) throw new IllegalArgumentException("Text too long (>65535 bytes)");
int st = subType & 0xFFFF;
if (st == (MsgSubType.TEXT_REPLY & 0xFFFF) && msgUtf8.length == 0) {
throw new IllegalArgumentException("Text payload is empty");
}
if (st == (MsgSubType.TEXT_REPLY & 0xFFFF)) {
if (toBlockchainName == null) throw new IllegalArgumentException("REPLY missing toBlockchainName");
byte[] nameUtf8 = toBlockchainName.getBytes(StandardCharsets.UTF_8);
if (nameUtf8.length == 0 || nameUtf8.length > 255)
throw new IllegalArgumentException("REPLY toBlockchainName utf8 len must be 1..255");
int cap = 1 + nameUtf8.length + 4 + 32 + 2 + msgUtf8.length;
ByteBuffer bb = ByteBuffer.allocate(cap).order(ByteOrder.BIG_ENDIAN);
bb.put((byte) nameUtf8.length);
bb.put(nameUtf8);
bb.putInt(toBlockGlobalNumber);
bb.put(toBlockHash32);
bb.putShort((short) msgUtf8.length);
bb.put(msgUtf8);
return bb.array();
}
// EDIT_REPLY
int cap = (4 + 32) + 2 + msgUtf8.length;
ByteBuffer bb = ByteBuffer.allocate(cap).order(ByteOrder.BIG_ENDIAN);
bb.putInt(toBlockGlobalNumber);
bb.put(toBlockHash32);
bb.putShort((short) msgUtf8.length);
bb.put(msgUtf8);
return bb.array();
}
/* ====================== BodyHasTarget ====================== */
@Override public String toBchName() { return toBlockchainName; }
@Override public Integer toBlockGlobalNumber() { return toBlockGlobalNumber; }
@Override public byte[] toBlockHashBytes() { return toBlockHash32; }
public boolean isEditReply() {
return (subType & 0xFFFF) == (MsgSubType.TEXT_EDIT_REPLY & 0xFFFF);
}
/* ====================== helpers ====================== */
private static String readStrictUtf8Len16(ByteBuffer bb, String fieldName, boolean allowEmpty) {
int len = Short.toUnsignedInt(bb.getShort());
if (len == 0) {
if (allowEmpty) return "";
throw new IllegalArgumentException(fieldName + " is empty");
}
if (bb.remaining() < len) throw new IllegalArgumentException(fieldName + " payload too short (len=" + len + ")");
byte[] bytes = new byte[len];
bb.get(bytes);
var decoder = StandardCharsets.UTF_8.newDecoder()
.onMalformedInput(CodingErrorAction.REPORT)
.onUnmappableCharacter(CodingErrorAction.REPORT);
try {
String s = decoder.decode(ByteBuffer.wrap(bytes)).toString();
if (!allowEmpty && s.isBlank()) throw new IllegalArgumentException(fieldName + " is blank");
return s;
} catch (CharacterCodingException e) {
throw new IllegalArgumentException(fieldName + " is not valid UTF-8", e);
}
}
private static void ensureMin(ByteBuffer bb, int need, String msg) {
if (bb.remaining() < need) throw new IllegalArgumentException(msg + " (need=" + need + ", remaining=" + bb.remaining() + ")");
}
private static void ensureNoTail(ByteBuffer bb, String ctx) {
if (bb.remaining() != 0) throw new IllegalArgumentException("Unexpected tail bytes for " + ctx + ", remaining=" + bb.remaining());
}
}