Add packet codecs across Handshake, Login, Configuration, and Play stages

libmc-common/src/commonMain/kotlin/cn/rtast/libmc/common/buffer.kt

@@ -21,6 +21,7 @@ public expect class BytesBuffer {
     public fun writeBoolean(value: Boolean)
 
     public fun readByte(): Byte
+    public fun readUByte(): UByte
     public fun readShort(endian: ByteOrder = ByteOrder.BIG_ENDIAN): Short
     public fun readInt(endian: ByteOrder = ByteOrder.BIG_ENDIAN): Int
     public fun readLong(endian: ByteOrder = ByteOrder.BIG_ENDIAN): Long

libmc-common/src/commonMain/kotlin/cn/rtast/libmc/common/codec.kt

@@ -9,18 +9,10 @@ package cn.rtast.libmc.common
 
 public interface Encoder<in T> {
     public fun encode(buffer: BytesBuffer, value: T)
-
-    public fun encodeToByteArray(value: T): ByteArray {
-        val buf = BytesBuffer()
-        encode(buf, value)
-        return buf.toByteArray()
-    }
 }
 
 public interface Decoder<out T> {
     public fun decode(buffer: BytesBuffer): T
-
-    public fun decodeFromByteArray(bytes: ByteArray): T = decode(bytes.wrap())
 }
 
 public interface PacketCodec<T> : Encoder<T>, Decoder<T>

libmc-common/src/commonMain/kotlin/cn/rtast/libmc/common/mc_primitives.kt

@@ -130,14 +130,6 @@ public fun BytesBuffer.writePrefixedByteArray(data: ByteArray) {
     this.writeBytes(data)
 }
 
-public fun BytesBuffer.readOptionalPrefixedByteArray(): ByteArray? {
-    val isPresent = this.readBoolean()
-    return if (isPresent) {
-        val length = this.readVarInt()
-        this.readBytes(length)
-    } else null
-}
-
 public fun BytesBuffer.writeOptionalPrefixedByteArray(data: ByteArray?) {
     if (data != null) {
         this.writeBoolean(true)
@@ -146,18 +138,6 @@ public fun BytesBuffer.writeOptionalPrefixedByteArray(data: ByteArray?) {
     } else this.writeBoolean(false)
 }
 
-public fun BytesBuffer.readPrefixedVarIntArray(): List<Int> {
-    val length = readVarInt()
-    val list = ArrayList<Int>(length)
-    repeat(length) { list.add(readVarInt()) }
-    return list
-}
-
-public fun BytesBuffer.writePrefixedVarIntArray(value: List<Int>) {
-    writeVarInt(value.size)
-    for (item in value) writeVarInt(item)
-}
-
 public fun BytesBuffer.readPrefixedStringArray(): List<String> {
     val length = readVarInt()
     val list = ArrayList<String>(length)
@@ -170,7 +150,83 @@ public fun BytesBuffer.writePrefixedStringArray(value: List<String>) {
     for (item in value) writeMcString(item)
 }
 
-public inline fun <T> BytesBuffer.writePrefixedArray(value: List<T>, writeItem: BytesBuffer.(T) -> Unit) {
-    writeVarInt(value.size)
-    for (item in value) writeItem(item)
+public inline fun <T> BytesBuffer.readOptional(block: BytesBuffer.() -> T): T? {
+    val hasData = this.readBoolean()
+    return if (hasData) block.invoke(this) else null
+}
+
+/**
+ * buffer.writeOptional(value.someValue) { writeBlockPos(it) }
+ */
+public inline fun <T> BytesBuffer.writeOptional(value: T?, block: BytesBuffer.(T) -> Unit) {
+    if (value != null) {
+        this.writeBoolean(true)
+        block.invoke(this, value)
+    } else this.writeBoolean(false)
+}
+
+public inline fun <T> BytesBuffer.readPrefixed(reader: BytesBuffer.() -> T): List<T> {
+    val count = this.readVarInt()
+    val list = ArrayList<T>(count)
+    repeat(count) { _ -> list.add(this.reader()) }
+    return list
+}
+
+public inline fun <T> BytesBuffer.writePrefixed(list: List<T>, writer: BytesBuffer.(T) -> Unit) {
+    this.writeVarInt(list.size)
+    for (item in list) this.writer(item)
+}
+
+public fun BytesBuffer.readBitSet(): LongArray {
+    val count = this.readVarInt()
+    return LongArray(count) { this.readLong() }
+}
+
+public fun BytesBuffer.writeBitSet(data: LongArray) {
+    this.writeVarInt(data.size)
+    for (i in data.indices) this.writeLong(data[i])
+}
+
+public fun LongArray.countSetBits(): Int {
+    var count = 0
+    for (i in indices) count += this[i].countOneBits()
+    return count
+}
+
+public fun LongArray.getBit(bitIndex: Int): Boolean {
+    val longIndex = bitIndex shr 6
+    if (longIndex !in this.indices) return false
+    val bitOffset = bitIndex and 63
+    return (this[longIndex] and (1L shl bitOffset)) != 0L
+}
+
+public sealed interface IdSet {
+    public data class Tag(val tagName: String) : IdSet
+    public data class Entries(val ids: List<Int>) : IdSet
+}
+
+public fun BytesBuffer.readIdSet(): IdSet {
+    val type = this.readVarInt()
+    return if (type == 0) {
+        IdSet.Tag(tagName = this.readMcString())
+    } else {
+        val count = type - 1
+        val ids = ArrayList<Int>(count)
+        (0 until count).forEach { _ -> ids.add(this.readVarInt()) }
+        IdSet.Entries(ids)
+    }
+}
+
+public fun BytesBuffer.writeIdSet(idSet: IdSet) {
+    when (idSet) {
+        is IdSet.Tag -> {
+            this.writeVarInt(0)
+            this.writeMcString(idSet.tagName)
+        }
+
+        is IdSet.Entries -> {
+            this.writeVarInt(idSet.ids.size + 1)
+            for (id in idSet.ids) this.writeVarInt(id)
+        }
+    }
 }

libmc-common/src/jvmMain/kotlin/cn/rtast/libmc/common/buffer.jvm.kt

@@ -90,6 +90,7 @@ public actual class BytesBuffer {
         return array[readOffset++]
     }
 
+    public actual fun readUByte(): UByte = this.readByte().toUByte()
     public actual fun readShort(endian: ByteOrder): Short = readBytes(2).toShort(endian)
     public actual fun readInt(endian: ByteOrder): Int = readBytes(4).toInt(endian)
     public actual fun readLong(endian: ByteOrder): Long = readBytes(8).toLong(endian)

libmc-common/src/nativeMain/kotlin/cn/rtast/libmc/common/buffer.native.kt

@@ -47,6 +47,7 @@ public actual class BytesBuffer {
     public actual fun writeBoolean(value: Boolean): Unit = _delegateBuf.writeByte(if (value) 0x01 else 0x00)
 
     public actual fun readByte(): Byte = _delegateBuf.readByte()
+    public actual fun readUByte(): UByte = this.readByte().toUByte()
     public actual fun readShort(endian: ByteOrder): Short =
         if (endian == ByteOrder.BIG_ENDIAN) _delegateBuf.readShort() else _delegateBuf.readShortLe()