From 79d9da259e2ecafe92358e9895edcc407b37a160 Mon Sep 17 00:00:00 2001
From: hkc <hatkidchan@gmail.com>
Date: Fri, 25 Aug 2023 23:16:51 +0300
Subject: [PATCH] Added back synchronous DataInputStream and related

---
 bta_proxy/datainputstream.py              | 71 +++++++++++++++++++++++
 bta_proxy/entitydata.py                   | 26 ++++++++-
 bta_proxy/itemstack.py                    |  9 ++-
 bta_proxy/packets/packet102windowclick.py |  2 -
 4 files changed, 104 insertions(+), 4 deletions(-)

diff --git a/bta_proxy/datainputstream.py b/bta_proxy/datainputstream.py
index be357e3..a0ec305 100644
--- a/bta_proxy/datainputstream.py
+++ b/bta_proxy/datainputstream.py
@@ -62,3 +62,74 @@ class AsyncDataInputStream:
         size = await self.read_short()
         return (await self.read_bytes(size)).decode('utf-8')
 
+class SyncDataInputStream:
+    def __init__(self, buffer: bytes):
+        self._buffer = buffer
+        self._cursor = 0
+
+    def read_bytes(self, n: int) -> bytes:
+        if self._cursor + n > len(self._buffer):
+            raise EOFError('stream overread')
+        blob = self._buffer[self._cursor : self._cursor + n]
+        self._cursor += n
+        return blob
+
+    def empty(self):
+        return self._cursor >= len(self._buffer) - 1
+
+    def end(self) -> bytes:
+        return self.read_bytes(len(self._buffer) - self._cursor)
+
+    def read(self) -> int:
+        if self._cursor >= len(self._buffer):
+            raise EOFError(f'stream overread in {self._buffer} at {self._cursor}')
+        self._cursor += 1
+        return self._buffer[self._cursor - 1]
+
+    def read_boolean(self) -> bool:
+        return self.read() != 0
+
+    def read_short(self) -> int:
+        return struct.unpack('>h', self.read_bytes(2))[0]
+
+    def read_ushort(self) -> int:
+        return struct.unpack('>H', self.read_bytes(2))[0]
+
+    def read_int(self) -> int:
+        return struct.unpack('>i', self.read_bytes(4))[0]
+
+    def read_uint(self) -> int:
+        return struct.unpack('>I', self.read_bytes(4))[0]
+
+    def read_long(self) -> int:
+        return struct.unpack('>q', self.read_bytes(8))[0]
+
+    def read_ulong(self) -> int:
+        return struct.unpack('>Q', self.read_bytes(8))[0]
+
+    def read_float(self) -> float:
+        return struct.unpack('>f', self.read_bytes(4))[0]
+
+    def read_double(self) -> float:
+        return struct.unpack('>d', self.read_bytes(8))[0]
+
+    def read_char(self) -> str:
+        return chr(self.read_ushort())
+
+    def read_varint(self, bits: int = 32) -> int:
+        value: int = 0
+        position: int = 0
+        while True:
+            byte = self.read()
+            value |= (byte & 0x7F) << position
+            if ((byte & 0x80) == 0):
+                break
+            position += 7
+            if position >= bits:
+                raise ValueError('varint too big')
+        return value
+
+    def read_string(self) -> str:
+        size = self.read_short()
+        return self.read_bytes(size).decode('utf-8')
+
diff --git a/bta_proxy/entitydata.py b/bta_proxy/entitydata.py
index aa51c96..889b01b 100644
--- a/bta_proxy/entitydata.py
+++ b/bta_proxy/entitydata.py
@@ -1,6 +1,6 @@
 
 from typing import Any
-from bta_proxy.datainputstream import AsyncDataInputStream
+from bta_proxy.datainputstream import AsyncDataInputStream, SyncDataInputStream
 from enum import Enum
 from dataclasses import dataclass
 
@@ -46,3 +46,27 @@ class EntityData:
                     items.append(DataItem(item_type, item_id, (x, y, z)))
         return items
 
+    @classmethod
+    def read_from_sync(cls, dis: SyncDataInputStream) -> list[DataItem]:
+        items = []
+        while (data := dis.read()) != 0x7F:
+            item_type = DataItemType((data & 0xE0) >> 5)
+            item_id: int = data & 0x1F
+            match item_type:
+                case DataItemType.BYTE:
+                    items.append(DataItem(item_type, item_id, dis.read()))
+                case DataItemType.SHORT:
+                    items.append(DataItem(item_type, item_id, dis.read_short()))
+                case DataItemType.FLOAT:
+                    items.append(DataItem(item_type, item_id, dis.read_float()))
+                case DataItemType.STRING:
+                    items.append(DataItem(item_type, item_id, dis.read_string()))
+                case DataItemType.ITEMSTACK:
+                    items.append(DataItem(item_type, item_id, ItemStack.read_from_sync(dis)))
+                case DataItemType.CHUNK_COORDINATES:
+                    x = dis.read_float()
+                    y = dis.read_float()
+                    z = dis.read_float()
+                    items.append(DataItem(item_type, item_id, (x, y, z)))
+        return items
+
diff --git a/bta_proxy/itemstack.py b/bta_proxy/itemstack.py
index 97edb2a..6888d41 100644
--- a/bta_proxy/itemstack.py
+++ b/bta_proxy/itemstack.py
@@ -1,5 +1,5 @@
 
-from bta_proxy.datainputstream import AsyncDataInputStream
+from bta_proxy.datainputstream import AsyncDataInputStream, SyncDataInputStream
 
 
 class ItemStack:
@@ -15,3 +15,10 @@ class ItemStack:
         count = await stream.read()
         data = await stream.read_ushort()
         return cls(item_id, count, data)
+
+    @classmethod
+    def read_from_sync(cls, stream: SyncDataInputStream) -> 'ItemStack':
+        item_id = stream.read_short()
+        count = stream.read()
+        data = stream.read_ushort()
+        return cls(item_id, count, data)
diff --git a/bta_proxy/packets/packet102windowclick.py b/bta_proxy/packets/packet102windowclick.py
index a935faf..082d7f5 100644
--- a/bta_proxy/packets/packet102windowclick.py
+++ b/bta_proxy/packets/packet102windowclick.py
@@ -1,5 +1,3 @@
-from bta_proxy.datainputstream import AsyncDataInputStream
-from bta_proxy.itemstack import ItemStack
 from .base import Packet
 
 class Packet102WindowClick(Packet, packet_id=102):