1 files changed, 64 insertions, 0 deletions
diff --git a/.venv/lib/python3.12/site-packages/hpack/huffman.py b/.venv/lib/python3.12/site-packages/hpack/huffman.py
new file mode 100644
index 00000000..f5b06c5e
--- /dev/null
+++ b/.venv/lib/python3.12/site-packages/hpack/huffman.py
@@ -0,0 +1,64 @@
+"""
+An implementation of a bitwise prefix tree specially built for decoding
+Huffman-coded content where we already know the Huffman table.
+"""
+from __future__ import annotations
+
+
+class HuffmanEncoder:
+    """
+    Encodes a string according to the Huffman encoding table defined in the
+    HPACK specification.
+    """
+
+    def __init__(self, huffman_code_list: list[int], huffman_code_list_lengths: list[int]) -> None:
+        self.huffman_code_list = huffman_code_list
+        self.huffman_code_list_lengths = huffman_code_list_lengths
+
+    def encode(self, bytes_to_encode: bytes | None) -> bytes:
+        """
+        Given a string of bytes, encodes them according to the HPACK Huffman
+        specification.
+        """
+        # If handed the empty string, just immediately return.
+        if not bytes_to_encode:
+            return b""
+
+        final_num = 0
+        final_int_len = 0
+
+        # Turn each byte into its huffman code. These codes aren't necessarily
+        # octet aligned, so keep track of how far through an octet we are. To
+        # handle this cleanly, just use a single giant integer.
+        for byte in bytes_to_encode:
+            bin_int_len = self.huffman_code_list_lengths[byte]
+            bin_int = self.huffman_code_list[byte] & (
+                2 ** (bin_int_len + 1) - 1
+            )
+            final_num <<= bin_int_len
+            final_num |= bin_int
+            final_int_len += bin_int_len
+
+        # Pad out to an octet with ones.
+        bits_to_be_padded = (8 - (final_int_len % 8)) % 8
+        final_num <<= bits_to_be_padded
+        final_num |= (1 << bits_to_be_padded) - 1
+
+        # Convert the number to hex and strip off the leading '0x' and the
+        # trailing 'L', if present.
+        s = hex(final_num)[2:].rstrip("L")
+
+        # If this is odd, prepend a zero.
+        s = "0" + s if len(s) % 2 != 0 else s
+
+        # This number should have twice as many digits as bytes. If not, we're
+        # missing some leading zeroes. Work out how many bytes we want and how
+        # many digits we have, then add the missing zero digits to the front.
+        total_bytes = (final_int_len + bits_to_be_padded) // 8
+        expected_digits = total_bytes * 2
+
+        if len(s) != expected_digits:
+            missing_digits = expected_digits - len(s)
+            s = ("0" * missing_digits) + s
+
+        return bytes.fromhex(s)