GRM-51: refactor: convert shell scripts and inline workflow scripts to Python

scripts/ci/post_merge.py

@@ -7,6 +7,7 @@ Usage:
 
 import os
 import re
+import subprocess  # nosec B404
 
 import click
 from dotenv import load_dotenv  # pyright: ignore[reportMissingImports,reportUnknownVariableType]
@@ -19,6 +20,32 @@ from gitea_runner_manager.i18n import _
 load_dotenv(override=True)
 
 
+def _get_git_commit_message() -> str:
+    """Get the full commit message of the latest commit."""
+    result = subprocess.run(  # nosec B603 B607
+        ["git", "log", "-1", "--pretty=%B"],
+        capture_output=True,
+        text=True,
+        check=False,
+    )
+    if result.returncode != 0:
+        raise click.ClickException(f"git log failed: {result.stderr.strip()}")
+    return result.stdout.strip()
+
+
+def _get_git_commit_sha() -> str:
+    """Get the SHA of the latest commit."""
+    result = subprocess.run(  # nosec B603 B607
+        ["git", "rev-parse", "HEAD"],
+        capture_output=True,
+        text=True,
+        check=False,
+    )
+    if result.returncode != 0:
+        raise click.ClickException(f"git rev-parse failed: {result.stderr.strip()}")
+    return result.stdout.strip()
+
+
 def extract_task_id(commit_msg: str) -> str:
     """Extract GRM-N task identifier from the first line of commit message."""
     first_line = commit_msg.split("\n")[0]
@@ -69,9 +96,16 @@ def build_comment(task_id: str, conv_msg: str, commit_sha: str) -> str:
 
 
 @click.command()
-@click.argument("commit_msg")
+@click.argument("commit_msg", required=False)
 @click.option("--commit-sha", default="", help="Commit SHA")
-def main(commit_msg: str, commit_sha: str) -> None:
+@click.option("--from-git", is_flag=True, default=False, help="Read commit message and SHA from git.")
+def main(commit_msg: str | None, commit_sha: str, from_git: bool) -> None:
+    if from_git:
+        commit_msg = _get_git_commit_message()
+        if not commit_sha:
+            commit_sha = _get_git_commit_sha()
+    if not commit_msg:
+        raise click.ClickException("commit_msg argument is required (or use --from-git)")
     token = os.environ.get("VIKUNJA_TOKEN", "")
     if not token:
         raise click.ClickException(_("ERROR: VIKUNJA_TOKEN is not set."))