#!/usr/bin/env python3

import json
import logging
import subprocess
from datetime import datetime, timezone

RESTIC_ENV = "/etc/restic/edge01.env"
LOGGER = logging.getLogger(__name__)


def collect():
    cmd = f'. "{RESTIC_ENV}" && restic snapshots --json'

    result = subprocess.run(
        ["bash", "-c", cmd],
        capture_output=True,
        text=True,
    )

    if result.returncode != 0:
        LOGGER.error("Restic snapshots failed: %s", result.stderr.strip())
        return {
            "state": "offline",
            "status": "error",
            "summary": "Backup error",
            "detail": "Restic snapshot query failed; see collector logs",
        }

    try:
        snapshots = json.loads(result.stdout)
    except json.JSONDecodeError:
        LOGGER.error("Restic snapshots returned invalid JSON")
        return {
            "state": "offline",
            "status": "error",
            "summary": "Backup error",
            "detail": "Restic returned invalid snapshot data; see collector logs",
        }

    if not isinstance(snapshots, list):
        LOGGER.error("Restic snapshots returned an unexpected JSON shape")
        return {
            "state": "offline",
            "status": "error",
            "summary": "Backup error",
            "detail": "Restic returned an unexpected snapshot response; see collector logs",
        }

    if not snapshots:
        return {
            "state": "offline",
            "status": "error",
            "summary": "Backup error",
            "detail": "Restic repository contains no snapshots",
            "snapshot_count": 0,
        }

    try:
        latest = max(
            snapshots,
            key=lambda snapshot: datetime.fromisoformat(snapshot["time"]),
        )
        latest_time = datetime.fromisoformat(latest["time"])
    except (KeyError, TypeError, ValueError):
        LOGGER.error("Restic snapshots contained an invalid timestamp")
        return {
            "state": "offline",
            "status": "error",
            "summary": "Backup error",
            "detail": "Restic returned snapshots without valid timestamps; see collector logs",
            "snapshot_count": len(snapshots),
        }

    age_seconds = max(0, int((datetime.now(timezone.utc) - latest_time).total_seconds()))
    age_hours, remainder = divmod(age_seconds, 3600)
    age_minutes = remainder // 60
    age = f"{age_hours}h {age_minutes}m" if age_hours else f"{age_minutes}m"

    return {
        "state": "online",
        "status": "healthy",
        "summary": "Healthy",
        "detail": f"{len(snapshots)} snapshots · latest {latest_time.isoformat()} · age {age}",
        "snapshot_count": len(snapshots),
        "latest_snapshot": latest_time.isoformat(),
        "latest_snapshot_age": age,
        "latest_snapshot_age_seconds": age_seconds,
    }