#!/usr/bin/env bash
set -euo pipefail

SERVICE_NAME="${SERVICE_NAME:-skd}"
UPDATE_SERVICE_URL="${SKD_UPDATE_SERVICE_URL:-https://update.wlkns.org}"
PROJECT_ID="${SKD_UPDATE_PROJECT_ID:-safe-kiddo-control}"
UPDATE_TOKEN="${SKD_UPDATE_TOKEN:-}"
STATUS_URL="${UPDATE_SERVICE_URL}/v1/projects/${PROJECT_ID}/status"
INSTALL_DIR="${INSTALL_DIR:-/opt/sk}"
STATUS_FILE="${SKD_UPDATE_STATUS_FILE:-/var/lib/skd/update_status.json}"
LOG_FILE="${SKD_UPDATE_LOG_FILE:-/var/lib/skd/update_logs.jsonl}"

log() {
  echo "[$(date '+%Y-%m-%d %H:%M:%S')] $*"
}

write_status() {
  local status="$1"
  local error="${2:-}"
  local version="$3"
  local timestamp
  timestamp="$(date -u '+%Y-%m-%dT%H:%M:%SZ')"
  SKD_STATUS="${status}" SKD_ERROR="${error}" SKD_VERSION="${version}" \
    SKD_STATUS_FILE="${STATUS_FILE}" SKD_LOG_FILE="${LOG_FILE}" python3 - <<'PY'
import json
import os
from datetime import datetime, timezone
from pathlib import Path

status = os.environ["SKD_STATUS"]
error = os.environ.get("SKD_ERROR", "")
version = os.environ.get("SKD_VERSION", "unknown")
status_file = Path(os.environ["SKD_STATUS_FILE"])
log_file = Path(os.environ["SKD_LOG_FILE"])

status_file.parent.mkdir(parents=True, exist_ok=True)
log_file.parent.mkdir(parents=True, exist_ok=True)

payload = {
    "device_id": os.uname().nodename,
    "version": version,
    "status": status,
    "error": error,
    "timestamp": datetime.now(timezone.utc).strftime("%Y-%m-%dT%H:%M:%SZ"),
}
status_file.write_text(json.dumps(payload), encoding="utf-8")
with log_file.open("a", encoding="utf-8") as handle:
    handle.write(json.dumps(payload) + "\n")
PY
  local payload
  payload=$(cat <<JSON
{
  "project_id": "${PROJECT_ID}",
  "version": "${version}",
  "status": "${status}",
  "timestamp": "${timestamp}",
  "client_id": "$(hostname)",
  "error_code": "${error}",
  "reason": "${error}"
}
JSON
)
  if [[ -n "${UPDATE_TOKEN}" ]]; then
    curl -sS -X POST -H "Authorization: Bearer ${UPDATE_TOKEN}" -H "Content-Type: application/json" \
      -d "${payload}" "${STATUS_URL}" >/dev/null || true
  fi
}


LATEST_BACKUP="$(ls -dt /opt/sk_backup_* 2>/dev/null | head -1 || true)"
if [[ -z "${LATEST_BACKUP}" ]]; then
  log "No backup found; rollback aborted."
  write_status "failed" "no backup found" "unknown"
  exit 1
fi

VERSION="unknown"
if [[ -f "${LATEST_BACKUP}/VERSION" ]]; then
  VERSION="$(cat "${LATEST_BACKUP}/VERSION" | tr -d '\n')"
fi

log "Stopping service ${SERVICE_NAME}..."
sudo systemctl stop "${SERVICE_NAME}.service"

FAILED_DIR="${INSTALL_DIR}_failed_$(date +%s)"
log "Swapping ${INSTALL_DIR} -> ${FAILED_DIR}..."
if [[ -d "${INSTALL_DIR}" ]]; then
  sudo mv "${INSTALL_DIR}" "${FAILED_DIR}"
fi
sudo mv "${LATEST_BACKUP}" "${INSTALL_DIR}"

log "Starting service ${SERVICE_NAME}..."
if sudo systemctl start "${SERVICE_NAME}.service"; then
  log "Rollback completed."
  write_status "success" "" "${VERSION}"
else
  log "Rollback failed."
  write_status "failed" "service start failed" "${VERSION}"
  exit 1
fi