feat(bot,wizard): smart message filtering, encrypted standalone wizard, and file persistence

ai procurement/app/storage.py

@@ -0,0 +1,53 @@
+"""Persistent storage for draft attachments (proforma files)."""
+from datetime import datetime, timezone
+import logging
+import os
+from pathlib import Path
+import re
+from uuid import UUID, uuid4
+
+logger = logging.getLogger("bot.storage")
+
+
+def sanitize_filename(filename: str) -> str:
+    """Sanitize filename preserving Persian/Arabic/English letters, numbers, and extensions."""
+    raw = (filename or "proforma.pdf").strip()
+    name = Path(raw).name
+    # Remove control characters and path traversal
+    clean = re.sub(r'[\/\\:\*\?"<>\|\r\n\t]', "_", name)
+    clean = clean.strip(". ")
+    return clean or f"proforma_{uuid4().hex[:8]}.pdf"
+
+
+async def save_proforma_file(
+    draft_id: str | UUID,
+    file_name: str,
+    content: bytes,
+    mime_type: str | None = None,
+    storage_dir: str = "data/attachments/proformas",
+) -> dict:
+    """Save proforma bytes permanently to disk.
+
+    Returns dict metadata for persisting in draft payload.
+    """
+    clean_name = sanitize_filename(file_name)
+    target_dir = Path(storage_dir) / str(draft_id)
+    target_dir.mkdir(parents=True, exist_ok=True)
+
+    unique_prefix = uuid4().hex[:8]
+    saved_filename = f"{unique_prefix}_{clean_name}"
+    target_path = target_dir / saved_filename
+
+    # Write bytes to disk
+    target_path.write_bytes(content)
+    logger.info("Persisted proforma (%d bytes) to %s", len(content), target_path)
+
+    return {
+        "file_name": clean_name,
+        "saved_filename": saved_filename,
+        "saved_path": str(target_path.resolve()),
+        "relative_path": str(target_path.as_posix()),
+        "size_bytes": len(content),
+        "mime_type": mime_type or "application/octet-stream",
+        "saved_at": datetime.now(timezone.utc).isoformat(),
+    }