Add chunk relate impl and test case

src/knowledge/data/chunk.py

@@ -0,0 +1,43 @@
+from enum import Enum
+from ..object import ObjectID
+
+ChunkID = ObjectID
+
+class PositionType(Enum):
+    Unknown = 1
+    Device = 2
+    File = 3
+    FileRange = 4
+    ChunkManager = 5
+
+
+class PositionFileRange:
+    def __init__(self, path: str, range_begin: int, range_end: int):
+        self.path = path
+        self.range_begin = range_begin
+        self.range_end = range_end
+
+    def encode(self):
+        return f"{self.range_begin}:{self.range_end}:{self.path}"
+
+    @staticmethod
+    def decode(value: str):
+        parts = value.split(":")
+        if len(parts) < 3:
+            raise ValueError("Invalid input string")
+
+        try:
+            range_begin = int(parts[0])
+            range_end = int(parts[1])
+        except ValueError as e:
+            raise ValueError("Invalid range_begin or range_end string") from e
+
+        path = ":".join(parts[2:])
+        return PositionFileRange(path, range_begin, range_end)
+
+    def __str__(self):
+        return self.encode()
+
+    @staticmethod
+    def from_string(value: str):
+        return PositionFileRange.decode(value)