feat: reggaeton production system with intelligent sample selection and FLP generation

mcp/protocol/sysex.py

@@ -0,0 +1,65 @@
+"""
+FL-MCP Protocol — SysEx encoding/decoding.
+
+Protocol: F0 7D [nibble-encoded UTF-8 JSON] F7
+"""
+
+from __future__ import annotations
+
+SYSEX_ID = 0x7D
+
+
+def nibble_encode(data: bytes) -> list[int]:
+    """Split each byte into two nibbles (high, low) for MIDI data byte compliance (< 0x80).
+
+    Each byte 0x00-0xFF is split into two MIDI-safe bytes:
+    - high nibble: (byte >> 4) & 0x0F
+    - low nibble:  byte & 0x0F
+    """
+    result: list[int] = []
+    for byte in data:
+        result.append((byte >> 4) & 0x0F)
+        result.append(byte & 0x0F)
+    return result
+
+
+def nibble_decode(nibbles: list[int]) -> bytes:
+    """Reconstruct bytes from nibble pairs.
+
+    Each pair (high, low) reconstructs one byte:
+    byte = (high << 4) | low
+    """
+    result = bytearray()
+    for i in range(0, len(nibbles), 2):
+        if i + 1 < len(nibbles):
+            result.append(((nibbles[i] & 0x0F) << 4) | (nibbles[i + 1] & 0x0F))
+    return bytes(result)
+
+
+def encode_command(cmd: str, params: dict | None = None) -> list[int]:
+    """Encode a JSON command as a complete SysEx message: F0 7D [nibbles...] F7."""
+    import json
+
+    payload = json.dumps({"cmd": cmd, "params": params or {}})
+    nibbles = nibble_encode(payload.encode("utf-8"))
+    return [0xF0, SYSEX_ID] + nibbles + [0xF7]
+
+
+def decode_command(data: list[int]) -> dict | None:
+    """Decode a SysEx message back to JSON dict.
+
+    Returns None if the message is not a valid FL-MCP SysEx message.
+    """
+    if not data or len(data) < 4 or data[0] != 0xF0 or data[-1] != 0xF7:
+        return None
+    if data[1] != SYSEX_ID:
+        return None
+    import json
+
+    nibbles = data[2:-1]
+    if not nibbles:
+        return None
+    raw = nibble_decode(nibbles)
+    if not raw:
+        return None
+    return json.loads(raw.decode("utf-8"))