organize packages

modules/software/janitor/janitor-backend.nix

@@ -0,0 +1,189 @@
+{
+  den.aspects.janitor-backend = {
+    nixos = { pkgs, lib, config, ... }:
+    let
+      cfg = config.services.janitor;
+
+      janitorScript = pkgs.writeText "janitor.py" ''
+        import os
+        import sys
+        import json
+        import shutil
+        import time
+        import logging
+        from pathlib import Path
+
+        logging.basicConfig(
+            level=logging.INFO,
+            format="[janitor] %(message)s",
+            stream=sys.stdout,
+        )
+        log = logging.getLogger("janitor")
+
+        CONFIG_PATH = os.environ.get("JANITOR_CONFIG")
+
+
+        def load_config():
+            if not CONFIG_PATH or not os.path.exists(CONFIG_PATH):
+                raise FileNotFoundError(f"JANITOR_CONFIG not set or missing: {CONFIG_PATH}")
+            with open(CONFIG_PATH) as f:
+                return json.load(f)
+
+
+        def get_destination(extension, rules):
+            ext = extension.lower().lstrip(".")
+            for folder, extensions in rules.items():
+                if ext in extensions:
+                    return folder
+            return None
+
+
+        def resolve_dest(dest_key, watch_dir):
+            if os.path.isabs(dest_key):
+                return Path(dest_key)
+            return watch_dir.parent / dest_key
+
+
+        def unique_path(target):
+            if not target.exists():
+                return target
+            stem, suffix = target.stem, target.suffix
+            counter = 1
+            while True:
+                candidate = target.parent / f"{stem}_{counter}{suffix}"
+                if not candidate.exists():
+                    return candidate
+                counter += 1
+
+
+        def main():
+            try:
+                config = load_config()
+            except Exception as e:
+                log.error("Failed to load config: %s", e)
+                sys.exit(1)
+
+            grace_period = config.get("grace_period", 60)
+            rules = config.get("rules", {})
+            now = time.time()
+
+            for watch_dir_str in config.get("watched_dirs", []):
+                watch_dir = Path(os.path.expanduser(watch_dir_str))
+
+                if not watch_dir.exists():
+                    log.warning("Watched dir does not exist: %s", watch_dir)
+                    continue
+
+                for item in watch_dir.iterdir():
+                    if not item.is_file() or item.name.startswith("."):
+                        continue
+
+                    age = now - item.stat().st_mtime
+                    if age < grace_period:
+                        continue
+
+                    dest_key = get_destination(item.suffix, rules)
+                    if dest_key is None:
+                        continue
+
+                    target_dir = resolve_dest(dest_key, watch_dir)
+                    target_dir.mkdir(parents=True, exist_ok=True)
+
+                    target = unique_path(target_dir / item.name)
+
+                    try:
+                        shutil.move(str(item), str(target))
+                        log.info("Moved %s -> %s", item.name, target)
+                    except Exception as e:
+                        log.error("Failed to move %s: %s", item.name, e)
+
+
+        if __name__ == "__main__":
+            main()
+      '';
+
+      janitorConfig = pkgs.writeText "janitor_config.json" (builtins.toJSON {
+        grace_period = cfg.gracePeriod;
+        watched_dirs = cfg.watchedDirs;
+        rules = cfg.rules;
+      });
+
+    in {
+      options.services.janitor = {
+        enable = lib.mkEnableOption "file sorting janitor";
+
+        interval = lib.mkOption {
+          type = lib.types.str;
+          default = "5min";
+          description = "How often to run the janitor (systemd time span, e.g. \"5min\", \"1h\").";
+        };
+
+        gracePeriod = lib.mkOption {
+          type = lib.types.int;
+          default = 60;
+          description = "Seconds a file must remain unmodified before it is eligible to be moved.";
+        };
+
+        watchedDirs = lib.mkOption {
+          type = lib.types.listOf lib.types.str;
+          default = [ "~/Downloads" ];
+          description = "Directories to scan and sort. Supports ~ expansion.";
+        };
+
+        rules = lib.mkOption {
+          type = lib.types.attrsOf (lib.types.listOf lib.types.str);
+          default = { };
+          description = ''
+            Mapping of destination folder path to a list of file extensions (without leading dot).
+            Destinations are relative to the parent of the watched directory, or absolute if they
+            start with /.
+
+            Example:
+              rules = {
+                "Pictures/Downloads" = [ "jpg" "png" "gif" "webp" ];
+                "Videos/Downloads"   = [ "mp4" "mkv" "webm" ];
+                "/mnt/archive"       = [ "zip" "tar" ];
+              };
+          '';
+          example = lib.literalExpression ''
+            {
+              "Pictures/Downloads" = [ "jpg" "jpeg" "png" "gif" "webp" "avif" ];
+              "Videos/Downloads"   = [ "mp4" "mkv" "mov" "webm" "avi" ];
+              "Music/Downloads"    = [ "mp3" "flac" "wav" "ogg" "opus" "m4a" ];
+              "Documents/Downloads" = [ "pdf" "doc" "docx" "odt" "txt" "md" "epub" ];
+            }
+          '';
+        };
+
+        user = lib.mkOption {
+          type = lib.types.str;
+          default = "bug";
+          description = "User account the janitor service runs as.";
+        };
+      };
+
+      config = lib.mkIf cfg.enable {
+        systemd.services.janitor = {
+          description = "File sorting janitor";
+
+          environment.JANITOR_CONFIG = "${janitorConfig}";
+
+          serviceConfig = {
+            Type = "oneshot";
+            User = cfg.user;
+            ExecStart = "${pkgs.python3}/bin/python3 ${janitorScript}";
+          };
+        };
+
+        systemd.timers.janitor = {
+          wantedBy = [ "timers.target" ];
+
+          timerConfig = {
+            OnBootSec = "10m";
+            OnUnitActiveSec = cfg.interval;
+          };
+        };
+      };
+    };
+  };
+}