couple of enhancements

src/rmscene/scene_items.py

@@ -127,6 +127,7 @@ class Line(SceneItem):
     points: list[Point]
     thickness_scale: float
     starting_length: float
+    move_id: tp.Optional[CrdtId] = None
 
 
 ## Text
@@ -144,6 +145,7 @@ class ParagraphStyle(enum.IntEnum):
     BOLD = 3
     BULLET = 4
     BULLET2 = 5
+    CHECKBOX = 6
 
 
 END_MARKER = CrdtId(0, 0)

src/rmscene/scene_stream.py

@@ -99,6 +99,34 @@ def to_stream(self, writer: TaggedBlockWriter):
         writer.data.write_bytes(self.data)
 
 
+@dataclass
+class SceneInfo(Block):
+    BLOCK_TYPE: tp.ClassVar = 0x0D
+
+    def version_info(self, _) -> tuple[int, int]:
+        """Return (min_version, current_version) to use when writing."""
+        return (0, 1)
+
+    current_layer: LwwValue[CrdtId]
+    background_visible: LwwValue[bool]
+    root_document_visible: LwwValue[bool]
+
+    @classmethod
+    def from_stream(cls, stream: TaggedBlockReader) -> SceneInfo:
+        current_layer = stream.read_lww_id(1)
+        background_visible = stream.read_lww_bool(2)
+        root_document_visible = stream.read_lww_bool(3)
+
+        return SceneInfo(current_layer=current_layer,
+                         background_visible=background_visible,
+                         root_document_visible=root_document_visible)
+
+    def to_stream(self, writer: TaggedBlockWriter):
+        writer.write_lww_id(1, self.current_layer)
+        writer.write_lww_bool(2, self.background_visible)
+        writer.write_lww_bool(3, self.root_document_visible)
+
+
 @dataclass
 class AuthorIdsBlock(Block):
     BLOCK_TYPE: tp.ClassVar = 0x09
@@ -164,6 +192,12 @@ def to_stream(self, writer: TaggedBlockWriter):
 class TreeNodeBlock(Block):
     BLOCK_TYPE: tp.ClassVar = 0x02
 
+    def version_info(self, writer: TaggedBlockWriter) -> tuple[int, int]:
+        """Return (min_version, current_version) to use when writing."""
+        version = writer.options.get("version", Version("9999"))
+        # XXX this is a guess about which version this changed in
+        return (1, 2) if (version >= Version("3.4")) else (1, 1)
+
     group: si.Group
 
     @classmethod
@@ -217,7 +251,7 @@ def version_info(self, _) -> tuple[int, int]:
     merges_count: int
     text_chars_count: int
     text_lines_count: int
-    _unknown: int = 0
+    type_folio_use_count: int = 0
 
     @classmethod
     def from_stream(cls, stream: TaggedBlockReader) -> PageInfoBlock:
@@ -230,7 +264,7 @@ def from_stream(cls, stream: TaggedBlockReader) -> PageInfoBlock:
             text_lines_count=stream.read_int(4),
         )
         if stream.bytes_remaining_in_block():
-            info._unknown = stream.read_int(5)
+            info.type_folio_use_count = stream.read_int(5)
         return info
 
     def to_stream(self, writer: TaggedBlockWriter):
@@ -241,7 +275,7 @@ def to_stream(self, writer: TaggedBlockWriter):
         writer.write_int(4, self.text_lines_count)
         version = writer.options.get("version", Version("9999"))
         if version >= Version("3.2.2"):
-            writer.write_int(5, self._unknown)
+            writer.write_int(5, self.type_folio_use_count)
 
 
 @dataclass
@@ -355,7 +389,12 @@ def line_from_stream(stream: TaggedBlockReader, version: int = 2) -> si.Line:
     # XXX unused
     timestamp = stream.read_id(6)
 
-    return si.Line(color, tool, points, thickness_scale, starting_length)
+    if stream.bytes_remaining_in_block() >= 3:
+        move_id = stream.read_id(7)
+    else:
+        move_id = None
+
+    return si.Line(color, tool, points, thickness_scale, starting_length, move_id)
 
 
 def line_to_stream(line: si.Line, writer: TaggedBlockWriter, version: int = 2):
@@ -371,6 +410,8 @@ def line_to_stream(line: si.Line, writer: TaggedBlockWriter, version: int = 2):
     # XXX didn't save
     timestamp = CrdtId(0, 1)
     writer.write_id(6, timestamp)
+    if line.move_id is not None:
+        writer.write_id(7, line.move_id)
 
 
 @dataclass
@@ -395,6 +436,8 @@ def from_stream(cls, stream: TaggedBlockReader) -> SceneItemBlock:
             subclass = SceneLineItemBlock
         elif block_type == SceneTextItemBlock.BLOCK_TYPE:
             subclass = SceneTextItemBlock
+        elif block_type == SceneTombstoneItemBlock.BLOCK_TYPE:
+            subclass = SceneTombstoneItemBlock
         else:
             raise ValueError(
                 "unknown scene type %d in %s" % (block_type, stream.current_block)
@@ -500,6 +543,17 @@ def glyph_range_to_stream(stream: TaggedBlockWriter, item: si.GlyphRange):
             stream.data.write_float64(rect.h)
 
 
+class SceneTombstoneItemBlock(SceneItemBlock):
+    BLOCK_TYPE: tp.ClassVar = 0x08
+
+    @classmethod
+    def value_from_stream(cls, reader: TaggedBlockReader):
+        pass
+
+    def value_to_stream(self, writer: TaggedBlockWriter, value):
+        pass
+
+
 class SceneGlyphItemBlock(SceneItemBlock):
     BLOCK_TYPE: tp.ClassVar = 0x03
     ITEM_TYPE: tp.ClassVar = 0x01

tests/test_scene_stream.py

@@ -45,6 +45,7 @@ def _hex_lines(b, n=32):
         ("Lines_v2_updated.rm", "3.2"),  # extra 7fXXXX part of Line data was added
         ("Wikipedia_highlighted_p1.rm", "3.1"),
         ("Wikipedia_highlighted_p2.rm", "3.1"),
+        ("With_SceneInfo_Block.rm", "3.4"),  # XXX version?
     ],
 )
 def test_full_roundtrip(test_file, version):
@@ -259,15 +260,17 @@ def test_write_blocks():
 
 
 def test_blocks_keep_unknown_data():
-    # The "7f 010f" is new, unknown data
+    # The "8f 010f" is represents new, unknown data -- note that this might need
+    # to be changed in future if the next id starts to actually be used in a
+    # future update!
     data_hex = """
-    56000000 00020205
+    59000000 00020205
     1f 0219
     2f 021e
     3f 0000
     4f 0000
     54 0000 0000
-    6c 4000 0000
+    6c 4300 0000
        03
        14 0f000000
        24 00000000
@@ -278,11 +281,12 @@ def test_blocks_keep_unknown_data():
           83c2622d 30c30000 08000000
        6f 0001
        7f 010f
+       8f 0101
     """
     buf = BytesIO(HEADER_V6 + bytes.fromhex(data_hex))
     block = next(read_blocks(buf))
     assert isinstance(block, SceneLineItemBlock)
-    assert block.extra_data == bytes.fromhex("7f 010f")
+    assert block.extra_data == bytes.fromhex("8f 0101")
 
 
 def test_error_in_block_contained():