"""V2R2C1 adapter using the existing V2R1C7 deployment primitives.

The service identity and loopback port remain stable for a safe cutover.  The
new release is installed under its own immutable directory and keeps the
previous V2R1C7 release available for an explicit, owner-approved rollback.
"""
from __future__ import annotations

import json
import os
import shutil
import sys
from argparse import Namespace
from pathlib import Path
from typing import Any, Mapping

import v2r1c7_production_adapter as base


VERSION = "V2R2C1"
SERVICE = "aios-v2r1c7-production.service"
PORT = 18927
RELEASE_ROOT = Path("/opt/aios/releases")
CURRENT_LINK = Path("/opt/aios/v2r2c1")
ENV_FILE = Path("/etc/aios/aios-v2r2c1.env")
STATE_FILE = Path("/var/lib/aios/v2r2c1/deployment-state.json")
UNIT_FILE = Path("/etc/systemd/system/aios-v2r1c7-production.service")
ROLLBACK_ROOT = Path("/var/lib/aios/v2r2c1/rollback")

REQUIRED_MEMBERS = {
    "payload/VERSION",
    "payload/active-runtime/app/deployment_state.py",
    "payload/active-runtime/app/v2r1c6_privacy_tools.py",
    "payload/active-runtime/app/v2r2c1_health_service.py",
    "payload/deploy/aios-v2/systemd/aios-v2r1c7-production.service",
    "payload/deploy/aios-v2/v2r2c1-runtime-config.json",
    "payload/deploy/aios-v2/v2r2c1-rollback.json",
    "payload/scripts/probe_v2r2c1_health.py",
    "payload/scripts/rollback_v2r2c1_release.sh",
    "payload/BUILD-METADATA.json",
    "payload/ARTIFACT-MANIFEST.json",
    "payload/ROLLBACK-METADATA.json",
}


def _configure_base() -> None:
    base.VERSION = VERSION
    base.SERVICE = SERVICE
    base.PORT = PORT
    base.REQUIRED_MEMBERS = REQUIRED_MEMBERS


def _args() -> Namespace:
    return Namespace(
        release_root=RELEASE_ROOT,
        current_link=CURRENT_LINK,
        env_file=ENV_FILE,
        state_file=STATE_FILE,
        unit_file=UNIT_FILE,
        health_timeout=45,
    )


def load_request() -> dict[str, Any]:
    _configure_base()
    value = base.load_request()
    if value.get("version") != VERSION or value.get("production_service") != SERVICE or int(value.get("production_port", -1)) != PORT:
        raise ValueError("V2R2C1 production binding mismatch")
    return value


def _backup(path: Path, name: str) -> None:
    if path.is_file() and not path.is_symlink():
        ROLLBACK_ROOT.mkdir(parents=True, exist_ok=True)
        destination = ROLLBACK_ROOT / name
        if not destination.exists():
            shutil.copy2(path, destination)


def execute_request(value: Mapping[str, Any]) -> dict[str, Any]:
    _configure_base()
    if value.get("schema") != "aios.production-executor-request.v1":
        raise ValueError("request_schema_invalid")
    if value.get("operation") == "apply":
        _backup(UNIT_FILE, "aios-v2r1c7-production.service.previous")
        _backup(Path("/etc/aios/aios-v2r1c7.env"), "aios-v2r1c7.env.previous")
        _backup(Path("/var/lib/aios/v2r1c7/deployment-state.json"), "v2r1c7-deployment-state.previous")
        return base.install_release(_args(), value)
    if value.get("operation") == "probe":
        return base.probe(_args(), value)
    if value.get("operation") == "rollback":
        return rollback(value)
    raise ValueError("unsupported_operation")


def rollback(value: Mapping[str, Any]) -> dict[str, Any]:
    """Explicit rollback only; this adapter never invokes it automatically."""
    import subprocess

    subprocess.run(["systemctl", "stop", SERVICE], check=False, capture_output=True, text=True, timeout=45)
    previous_unit = ROLLBACK_ROOT / "aios-v2r1c7-production.service.previous"
    previous_env = ROLLBACK_ROOT / "aios-v2r1c7.env.previous"
    previous_state = ROLLBACK_ROOT / "v2r1c7-deployment-state.previous"
    if not previous_unit.is_file() or not previous_env.is_file():
        raise RuntimeError("ROLLBACK_RECEIPT_MISSING")
    UNIT_FILE.parent.mkdir(parents=True, exist_ok=True)
    ENV_FILE.parent.mkdir(parents=True, exist_ok=True)
    shutil.copy2(previous_unit, UNIT_FILE)
    shutil.copy2(previous_env, Path("/etc/aios/aios-v2r1c7.env"))
    if previous_state.is_file():
        Path("/var/lib/aios/v2r1c7").mkdir(parents=True, exist_ok=True)
        shutil.copy2(previous_state, Path("/var/lib/aios/v2r1c7/deployment-state.json"))
    subprocess.run(["systemctl", "daemon-reload"], check=True, capture_output=True, text=True, timeout=45)
    subprocess.run(["systemctl", "restart", SERVICE], check=True, capture_output=True, text=True, timeout=45)
    result = base.health("http://127.0.0.1:18927/health", {
        "version": "V2R1C7",
        "target_oid": str(json.loads(Path("/var/lib/aios/v2r1c7/deployment-state.json").read_text(encoding="utf-8")).get("commit_oid")),
        "artifact_sha256": str(json.loads(Path("/var/lib/aios/v2r1c7/deployment-state.json").read_text(encoding="utf-8")).get("artifact_sha256")),
    })
    return {"status": "ROLLED_BACK", "rollback_health": result, "automatic_rollback": False}


def main() -> int:
    try:
        value = load_request()
        result = execute_request(value)
        print(json.dumps(result, sort_keys=True))
        return 0
    except Exception as exc:
        print(json.dumps({"status": "FAIL_CLOSED", "error": type(exc).__name__, "reason": str(exc)}, sort_keys=True))
        return 2


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