Add auto-update for melange image if older than 30 days

Automatically checks the age of the local melange Docker image and pulls
an updated version if it's older than 30 days. Gives users a 15-second
window to abort with Ctrl+C before pulling.

Author: AmberArcadia

pre_commit_hooks/shellcheck_run_steps.py

@@ -2,11 +2,16 @@
 
 import argparse
 import contextlib
+import json
 import os
 import subprocess
+import sys
 import tempfile
+import time
 from collections.abc import Mapping
 from collections.abc import Sequence
+from datetime import datetime
+from datetime import timezone
 from typing import Any
 
 import ruamel.yaml
@@ -74,7 +79,61 @@ def do_shellcheck(
     return True
 
 
+def check_and_update_melange_image(image: str) -> None:
+    """Check if melange image is older than 30 days and pull if needed."""
+    try:
+        # Get image creation date
+        result = subprocess.run(
+            ["docker", "image", "inspect", image, "--format", "{{json .Created}}"],
+            capture_output=True,
+            text=True,
+            check=False,
+        )
+
+        if result.returncode != 0:
+            # Image doesn't exist locally, pull it
+            print(
+                f"Melange image not found locally, pulling {image}...",
+                file=sys.stderr,
+            )
+            subprocess.run(["docker", "pull", image], check=True)
+            return
+
+        # Parse the creation date
+        created_str = json.loads(result.stdout.strip())
+        created_date = datetime.fromisoformat(created_str.replace("Z", "+00:00"))
+        now = datetime.now(timezone.utc)
+        age_days = (now - created_date).days
+
+        if age_days > 30:
+            print(
+                f"⚠️  Melange image is {age_days} days old (created {created_date.strftime('%Y-%m-%d')})",
+                file=sys.stderr,
+            )
+            print(f"⚠️  Pulling updated melange image: {image}", file=sys.stderr)
+            print(
+                "⚠️  Press Ctrl+C now to abort or wait 15 seconds to continue...",
+                file=sys.stderr,
+            )
+
+            # Give user 15 seconds to abort
+            time.sleep(15)
+
+            print(f"Pulling {image}...", file=sys.stderr)
+            subprocess.run(["docker", "pull", image], check=True)
+            print("✓ Melange image updated successfully", file=sys.stderr)
+
+    except KeyboardInterrupt:
+        print("\n⚠️  Update aborted by user, using existing image", file=sys.stderr)
+    except Exception as e:
+        print(f"Warning: Failed to check/update melange image: {e}", file=sys.stderr)
+        print("Continuing with existing image...", file=sys.stderr)
+
+
 def main(argv: Sequence[str] | None = None) -> int:
+    # Check and update melange image if needed
+    check_and_update_melange_image(MelangeImage)
+
     parser = argparse.ArgumentParser()
     parser.add_argument(
         "filenames",