onboard_write.py

"""Atomic write of PREFERENCES.md with backup and existing-content detection."""
import os, shutil, tempfile

REL = ".agent/memory/personal/PREFERENCES.md"
_STUB_MARKERS = ("_(e.g.,", "<!-- generated by")


def is_customized(target_dir: str) -> bool:
    """Return True if PREFERENCES.md has real user content (not just stubs)."""
    path = os.path.join(target_dir, REL)
    try:
        text = open(path).read()
    except FileNotFoundError:
        return False
    # Already generated by this wizard → treat as customized
    if "<!-- generated by agentic-stack onboard" in text:
        return True
    # Original stub: every data line starts with _(e.g.,
    data_lines = [
        ln.strip() for ln in text.splitlines()
        if ln.strip() and not ln.strip().startswith(("#", ">", "##", "<!--"))
    ]
    stub_lines = [ln for ln in data_lines if any(m in ln for m in _STUB_MARKERS)]
    return bool(data_lines) and len(stub_lines) < len(data_lines)


def write_prefs(target_dir: str, content: str, force: bool = False) -> str:
    """Write content to PREFERENCES.md; return the absolute path written."""
    dest     = os.path.abspath(os.path.join(target_dir, REL))
    dest_dir = os.path.dirname(dest)

    if not os.path.isdir(dest_dir):
        raise RuntimeError(
            f".agent/memory/personal/ not found in {target_dir}\n"
            "Run the adapter install first, then re-run the wizard."
        )

    # Back up an existing customized file (non-destructive by default)
    if is_customized(target_dir) and not force:
        shutil.copy2(dest, dest + ".bak")

    # Atomic write via a temp file in the same directory
    fd, tmp = tempfile.mkstemp(dir=dest_dir, prefix=".prefs_tmp_")
    try:
        with os.fdopen(fd, "w", encoding="utf-8") as f:
            f.write(content)
        os.replace(tmp, dest)
    except Exception:
        try:
            os.unlink(tmp)
        except OSError:
            pass
        raise

    return dest