Added replacements. Added command line switch for dry-run

caya-clean/.gitignore

@@ -0,0 +1 @@
+__pycache__

caya-clean/caya_clean.py

@@ -1,14 +1,11 @@
+import argparse
 import hashlib
 import json
 import re
-import sys
 from datetime import datetime
 from pathlib import Path
 
 
-# Set to False after checking the output of a test run.
-DRY_RUN = True
-
 SCRIPT_DIR = Path(__file__).resolve().parent
 CONFIG_FILE = SCRIPT_DIR / "configuration.json"
 LOG_FILENAME = "caya-clean.log"
@@ -19,6 +16,30 @@ DATE_PATTERN = re.compile(r"^(?P<date>\d{8})T\d{4}Z\s+")
 CAYA_ID_PATTERN = re.compile(r"\s+[a-z0-9]{20,35}$", re.IGNORECASE)
 
 
+def parse_arguments() -> argparse.Namespace:
+    parser = argparse.ArgumentParser(
+        description=(
+            "Clean up and rename downloaded Caya letter files."
+        )
+    )
+
+    parser.add_argument(
+        "folder",
+        nargs="?",
+        type=Path,
+        default=Path.cwd(),
+        help="Folder containing the letter files.",
+    )
+
+    parser.add_argument(
+        "--dry-run",
+        action="store_true",
+        help="Show planned changes without modifying or deleting files.",
+    )
+
+    return parser.parse_args()
+
+
 def log_message(folder: Path, message: str):
     """Append a timestamped message to the folder logfile."""
     log_file = folder / LOG_FILENAME
@@ -31,31 +52,44 @@ def log_message(folder: Path, message: str):
 
 
 def load_config() -> dict:
-    """Load the configuration from configuration.json."""
+    """Load and validate configuration.json."""
     if not CONFIG_FILE.exists():
-        print(f"Configuration file not found: {CONFIG_FILE}")
+        raise FileNotFoundError(
-        sys.exit(1)
+            f"Configuration file not found: {CONFIG_FILE}"
+        )
 
     try:
         with CONFIG_FILE.open("r", encoding="utf-8") as file:
             config = json.load(file)
     except json.JSONDecodeError as error:
-        print(f"Invalid JSON in configuration file: {error}")
+        raise ValueError(
-        sys.exit(1)
+            f"Invalid JSON in configuration file: {error}"
+        ) from error
 
-    exceptions = config.get("umlaut_exceptions", [])
+    umlaut_exceptions = config.get("umlaut_exceptions", [])
 
-    if not isinstance(exceptions, list):
+    if not isinstance(umlaut_exceptions, list):
-        print("'umlaut_exceptions' must be a JSON array.")
+        raise ValueError("'umlaut_exceptions' must be a JSON array.")
-        sys.exit(1)
 
-    config["umlaut_exceptions"] = {
+    replacements = config.get("replacements", {})
+
+    if not isinstance(replacements, dict):
+        raise ValueError("'replacements' must be a JSON object.")
+
+    for source, target in replacements.items():
+        if not isinstance(source, str) or not isinstance(target, str):
+            raise ValueError(
+                "Replacement keys and values must both be strings."
+            )
+
+    return {
+        "umlaut_exceptions": {
             str(word).lower()
-        for word in exceptions
+            for word in umlaut_exceptions
+        },
+        "replacements": replacements,
     }
 
-    return config
-
 
 def file_hash(path: Path) -> str:
     """Calculate the SHA-256 hash of a file."""
@@ -68,10 +102,15 @@ def file_hash(path: Path) -> str:
     return hasher.hexdigest()
 
 
-def replace_umlauts(text: str, umlaut_exceptions: set[str]) -> str:
+def replace_umlauts(
+    text: str,
+    umlaut_exceptions: set[str],
+) -> str:
     """
     Replace ae/oe/ue with ä/ö/ü.
-    Words from the exception list are protected temporarily.
+
+    Exception strings are matched case-insensitively and protected
+    before the replacements are applied.
     """
     protected_words = {}
 
@@ -98,7 +137,30 @@ def replace_umlauts(text: str, umlaut_exceptions: set[str]) -> str:
     return text
 
 
-def clean_stem(stem: str, umlaut_exceptions: set[str]) -> str | None:
+def apply_replacements(text: str, replacements: dict[str, str]) -> str:
+    """Apply configured replacements case-insensitively."""
+    # Replace longer keys first to avoid partial matches.
+    replacement_items = sorted(
+        replacements.items(),
+        key=lambda item: len(item[0]),
+        reverse=True,
+    )
+
+    for source, target in replacement_items:
+        if not source:
+            continue
+
+        pattern = re.compile(re.escape(source), re.IGNORECASE)
+        text = pattern.sub(lambda _: target, text)
+
+    return text
+
+
+def clean_stem(
+    stem: str,
+    umlaut_exceptions: set[str],
+    replacements: dict[str, str],
+) -> str | None:
     """
     Create a cleaned filename stem.
 
@@ -121,8 +183,17 @@ def clean_stem(stem: str, umlaut_exceptions: set[str]) -> str | None:
     # Normalize whitespace and remove unnecessary separators.
     remainder = re.sub(r"\s+", " ", remainder).strip(" -_.")
 
-    # Convert ae/oe/ue to ä/ö/ü, respecting configured exceptions.
+    # Convert ae/oe/ue to ä/ö/ü.
-    remainder = replace_umlauts(remainder, umlaut_exceptions)
+    remainder = replace_umlauts(
+        remainder,
+        umlaut_exceptions,
+    )
+
+    # Apply configured replacements such as GMBH -> GmbH.
+    remainder = apply_replacements(
+        remainder,
+        replacements,
+    )
 
     if not remainder:
         return formatted_date
@@ -135,10 +206,14 @@ def is_clean_filename(path: Path) -> bool:
     return bool(re.match(r"^\d{4}-\d{2}-\d{2}\b", path.stem))
 
 
-def safely_delete(path: Path, folder: Path):
+def safely_delete(
-    """Delete a file or log the planned action in test mode."""
+    path: Path,
-    if DRY_RUN:
+    folder: Path,
-        log_message(folder, f"[TEST] DELETE {path.name}")
+    dry_run: bool,
+):
+    """Delete a file or log the planned action in dry-run mode."""
+    if dry_run:
+        log_message(folder, f"[DRY-RUN] DELETE {path.name}")
         return
 
     try:
@@ -151,12 +226,17 @@ def safely_delete(path: Path, folder: Path):
         )
 
 
-def safely_rename(old_path: Path, new_path: Path, folder: Path):
+def safely_rename(
-    """Rename a file or log the planned action in test mode."""
+    old_path: Path,
-    if DRY_RUN:
+    new_path: Path,
+    folder: Path,
+    dry_run: bool,
+):
+    """Rename a file or log the planned action in dry-run mode."""
+    if dry_run:
         log_message(
             folder,
-            f"[TEST] RENAME {old_path.name} -> {new_path.name}",
+            f"[DRY-RUN] RENAME {old_path.name} -> {new_path.name}",
         )
         return
 
@@ -175,18 +255,27 @@ def safely_rename(old_path: Path, new_path: Path, folder: Path):
 
 
 def main():
-    config = load_config()
+    arguments = parse_arguments()
-    umlaut_exceptions = config["umlaut_exceptions"]
 
-    folder = Path(sys.argv[1]) if len(sys.argv) > 1 else Path.cwd()
+    try:
+        config = load_config()
+    except (FileNotFoundError, ValueError) as error:
+        print(f"[ERROR] {error}")
+        return 1
+
+    folder = arguments.folder
 
     if not folder.is_dir():
-        print(f"Folder not found: {folder}")
+        print(f"[ERROR] Folder not found: {folder}")
-        sys.exit(1)
+        return 1
+
+    dry_run = arguments.dry_run
+    umlaut_exceptions = config["umlaut_exceptions"]
+    replacements = config["replacements"]
 
     log_message(
         folder,
-        f"[START] Processing folder; test_mode={DRY_RUN}",
+        f"[START] Processing folder; dry_run={dry_run}",
     )
 
     files = [
@@ -202,7 +291,7 @@ def main():
     if not files:
         log_message(folder, "[INFO] No files found")
         log_message(folder, "[END] Processing completed")
-        return
+        return 0
 
     log_message(folder, f"[INFO] Found {len(files)} file(s)")
 
@@ -222,7 +311,7 @@ def main():
     files_to_keep = set()
     files_to_delete = set()
 
-    # For identical files, prefer a file that already has a clean filename.
+    # Prefer an already-clean filename for identical files.
     for group in hash_groups.values():
         if len(group) == 1:
             files_to_keep.add(group[0])
@@ -248,16 +337,21 @@ def main():
 
     # Delete duplicate files.
     for path in files_to_delete:
-        safely_delete(path, folder)
+        safely_delete(path, folder, dry_run)
 
     # Rename remaining Caya original files.
     for path in files_to_keep:
-        new_stem = clean_stem(path.stem, umlaut_exceptions)
+        new_stem = clean_stem(
+            path.stem,
+            umlaut_exceptions,
+            replacements,
+        )
 
         if new_stem is None:
             log_message(
                 folder,
-                f"[SKIP] Filename does not match Caya format: {path.name}",
+                f"[SKIP] Filename does not match Caya format: "
+                f"{path.name}",
             )
             continue
 
@@ -276,30 +370,33 @@ def main():
             except OSError as error:
                 log_message(
                     folder,
-                    f"[ERROR] Could not compare {path.name} "
+                    f"[ERROR] Could not compare "
-                    f"and {target.name}: {error}",
+                    f"{path.name} and {target.name}: {error}",
                 )
                 continue
 
             if source_hash == target_hash:
                 log_message(
                     folder,
-                    f"[DUPLICATE] {path.name} matches existing {target.name}",
+                    f"[DUPLICATE] {path.name} matches "
+                    f"existing {target.name}",
                 )
-                safely_delete(path, folder)
+                safely_delete(path, folder, dry_run)
             else:
                 log_message(
                     folder,
-                    "[CONFLICT] Target already exists with different "
+                    "[CONFLICT] Target already exists with "
-                    f"content: {path.name} -> {target.name}",
+                    f"different content: {path.name} -> {target.name}",
                 )
 
             continue
 
-        safely_rename(path, target, folder)
+        safely_rename(path, target, folder, dry_run)
 
     log_message(folder, "[END] Processing completed")
 
+    return 0
+
 
 if __name__ == "__main__":
-    main()
+    raise SystemExit(main())

caya-clean/configuration.json

@@ -1,5 +1,11 @@
 {
   "umlaut_exceptions": [
+    "aktuell",
     "eue"
-  ]
+  ],
+  "replacements": {
+    "TOMTEC IMAGING SYSTEMS": "TOMTEC Imaging Systems",
+    "OPTIK VITZTHUM": "Optik Vitzthum",
+    "GMBH": "GmbH"
+  }
 }