#!/usr/bin/env python3
"""Probe installed Codex CLI retention support without mutating Codex state."""

from __future__ import annotations

import argparse
import json
import os
import re
import shutil
import subprocess
from pathlib import Path

SCHEMA_VERSION = "cto-codex-native-retention-probe.v1"
RETENTION_TERMS = ("retention", "cleanup", "prune", "archive")


def run_help(codex_bin: str, args: list[str]) -> dict[str, object]:
    command = [codex_bin, *args]
    try:
        completed = subprocess.run(
            command,
            check=False,
            capture_output=True,
            text=True,
            timeout=10,
        )
    except Exception as exc:
        return {
            "command": command,
            "returncode": None,
            "stdout": "",
            "stderr": str(exc),
            "ok": False,
        }
    return {
        "command": command,
        "returncode": completed.returncode,
        "stdout": completed.stdout,
        "stderr": completed.stderr,
        "ok": completed.returncode == 0,
    }


def parse_version(output: str) -> str | None:
    match = re.search(r"(\d+\.\d+\.\d+)", output)
    return match.group(1) if match else None


def read_version_cache(codex_home: Path) -> dict[str, object]:
    path = codex_home / "version.json"
    if not path.exists():
        return {"path": str(path), "present": False}
    try:
        payload = json.loads(path.read_text(encoding="utf-8"))
    except json.JSONDecodeError as exc:
        return {"path": str(path), "present": True, "parse_error": str(exc)}
    return {
        "path": str(path),
        "present": True,
        "latest_version": payload.get("latest_version"),
        "last_checked_at": payload.get("last_checked_at"),
        "dismissed_version": payload.get("dismissed_version"),
    }


def term_hits(text: str) -> list[str]:
    lowered = text.lower()
    return [term for term in RETENTION_TERMS if term in lowered]


def build_probe(codex_home: Path, codex_bin: str | None) -> dict[str, object]:
    resolved_bin = codex_bin or shutil.which("codex")
    help_results: list[dict[str, object]] = []
    installed_version = None
    if resolved_bin:
        version_result = run_help(resolved_bin, ["--version"])
        installed_version = parse_version(str(version_result.get("stdout", "")))
        help_results = [
            run_help(resolved_bin, ["--help"]),
            run_help(resolved_bin, ["exec", "--help"]),
            run_help(resolved_bin, ["exec", "resume", "--help"]),
            run_help(resolved_bin, ["resume", "--help"]),
            run_help(resolved_bin, ["features", "list"]),
        ]
    combined_help = "\n".join(str(result.get("stdout", "")) for result in help_results)
    version_cache = read_version_cache(codex_home)
    latest_version = version_cache.get("latest_version")
    update_available = bool(installed_version and latest_version and installed_version != latest_version)
    retention_hits = term_hits(combined_help)
    return {
        "schema_version": SCHEMA_VERSION,
        "codex_home": str(codex_home),
        "codex_bin": resolved_bin,
        "metadata_only": True,
        "mutation_performed": False,
        "raw_transcript_bodies_read": False,
        "raw_thread_text_fields_read": False,
        "state_db_mutation": False,
        "session_jsonl_deleted": False,
        "logs_deleted_or_truncated": False,
        "installed_version": installed_version,
        "version_cache": version_cache,
        "update_available": update_available,
        "native_retention_cleanup_command_advertised": bool(retention_hits),
        "native_retention_terms_seen": retention_hits,
        "ephemeral_prevention_advertised": "--ephemeral" in combined_help,
        "help_surfaces_checked": [
            "codex --help",
            "codex exec --help",
            "codex exec resume --help",
            "codex resume --help",
            "codex features list",
        ],
        "decision": (
            "Installed Codex advertises ephemeral prevention but no native retention cleanup command."
            if not retention_hits
            else "Installed Codex advertises possible retention cleanup terms; inspect before custom mutation."
        ),
        "recommended_next": (
            "Decide whether to update Codex and re-run this probe before archive-only execution."
            if update_available
            else "Use guarded archive executor only with exact approval token."
        ),
        "false_effects": {
            "codex_update": False,
            "archive_threads": False,
            "delete_session_jsonl": False,
            "delete_logs": False,
            "sqlite_checkpoint_or_vacuum": False,
            "raw_transcript_body_read": False,
            "raw_thread_text_field_read": False,
            "core_source_mutation": False,
        },
    }


def validate_probe(probe: dict[str, object]) -> list[str]:
    errors: list[str] = []
    if probe.get("schema_version") != SCHEMA_VERSION:
        errors.append("schema_version_invalid")
    for field in [
        "metadata_only",
        "mutation_performed",
        "raw_transcript_bodies_read",
        "raw_thread_text_fields_read",
        "state_db_mutation",
        "session_jsonl_deleted",
        "logs_deleted_or_truncated",
    ]:
        expected = field == "metadata_only"
        if probe.get(field) is not expected:
            errors.append(f"{field}_invalid")
    if not probe.get("codex_bin"):
        errors.append("codex_bin_missing")
    if not probe.get("installed_version"):
        errors.append("installed_version_missing")
    if probe.get("ephemeral_prevention_advertised") is not True:
        errors.append("ephemeral_prevention_not_advertised")
    false_effects = probe.get("false_effects")
    if not isinstance(false_effects, dict):
        errors.append("false_effects_missing")
    else:
        for key, value in false_effects.items():
            if value is not False:
                errors.append(f"false_effect_not_false:{key}")
    return errors


def main() -> int:
    parser = argparse.ArgumentParser()
    parser.add_argument("--codex-home", default=os.environ.get("CODEX_HOME", str(Path.home() / ".codex")))
    parser.add_argument("--codex-bin")
    parser.add_argument("--check", action="store_true")
    args = parser.parse_args()

    probe = build_probe(Path(args.codex_home).expanduser(), args.codex_bin)
    errors = validate_probe(probe)
    if args.check:
        print(
            json.dumps(
                {
                    "ok": not errors,
                    "validator": "cto-codex-native-retention-probe",
                    "errors": errors,
                    "warnings": [],
                },
                indent=2,
                sort_keys=True,
            )
        )
        return 0 if not errors else 1
    probe["ok"] = not errors
    probe["errors"] = errors
    print(json.dumps(probe, indent=2, sort_keys=True))
    return 0 if not errors else 1


if __name__ == "__main__":
    raise SystemExit(main())