WIP set.py

reimplement/set.py

@@ -0,0 +1,64 @@
+# set.py - base64, golomb and set-string routines. analog set.c used in alt-rpm
+
+import hashlib
+from typing import List
+from typing import Tuple
+from dataclasses import dataclass
+
+
+@dataclass
+class Set:
+    """just a bag of strings and their hash values.
+
+    Attributes:
+        count (int): The number of elements in the set.
+        labels (List[Tuple[str, int]]): A list of tuples, where each tuple contains a string and its corresponding hash value.
+    """
+
+    count: int
+    labels: List[Tuple[str, int]]  # List of tuples (string, hash value)
+
+
+def rpmsetcmp():
+    pass
+
+
+def set_new() -> Set:
+    """Create a new Set instance with count initialized to 0 and an empty list of labels."""
+    return Set(count=0, labels=[])
+
+
+def set_add(set: Set, label: str) -> None:
+    """Add a label to the set."""
+    hash_value = hash(label)
+    set.labels.append((label, hash_value))
+    set.count += 1
+
+
+def set_free(set: Set) -> None:
+    """Free the resources associated with the set."""
+    set.labels.clear()
+    set.count = 0
+
+
+def hash(label: str) -> int:
+    """Compute a stable 64-bit hash value for an ASCII label."""
+    digest = hashlib.blake2b(label.encode("ascii"), digest_size=8).digest()
+    return int.from_bytes(digest, byteorder="little", signed=False)
+
+
+def set_fini(set: Set, bpp: int) -> str | None:
+    """Finalize the set and return a set-string representation."""
+
+    if set.count < 1:
+        return None
+
+    # bpp < 10 in original code
+    if bpp < 2:
+        return None
+
+    if bpp > 64:
+        return None
+
+    # Placeholder implementation - replace with actual finalization logic
+    return f"Set with {set.count} elements"