#!/usr/bin/env bash
set -euo pipefail
umask 077

# 由宿主机 cron 每分钟调用。调度配置来自后台 system_configs，实际执行仍在宿主机，
# Web 后端不接触 Docker socket、备份载荷或客户端加密密码。

SCRIPT_DIR="$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)"
# shellcheck source=backup-common.sh
source "${SCRIPT_DIR}/backup-common.sh"

config_value() {
  local key="$1" fallback="$2" value
  value="$(backup_mysql_root_query "SELECT value FROM system_configs WHERE \`key\` = '${key}' LIMIT 1;" 2>/dev/null || true)"
  value="${value//$'\n'/}"
  printf '%s' "${value:-${fallback}}"
}

write_job_state() {
  local status_dir="$1" type="$2" status="$3" message="$4"
  mkdir -p "${status_dir}"
  {
    printf 'job_type=%q\n' "${type}"
    printf 'job_status=%q\n' "${status}"
    printf 'job_at=%q\n' "$(date -Iseconds)"
    printf 'job_message=%q\n' "${message}"
  } > "${status_dir}/last-job.env"
  chmod 600 "${status_dir}/last-job.env"
}

run_job() {
  local status_dir="$1" type="$2" script="$3"
  shift 3
  if "${script}" "$@"; then
    write_job_state "${status_dir}" "${type}" success '执行成功'
    "${SCRIPT_DIR}/backup-status.sh" write || true
    return
  fi
  local code=$?
  write_job_state "${status_dir}" "${type}" failed "执行失败（退出码 ${code}）"
  "${SCRIPT_DIR}/backup-status.sh" write || true
  return "${code}"
}

main() {
  backup_require_cmd docker
  backup_require_cmd flock
  local backup_dir status_dir enabled hour minute interval now_hour now_minute
  backup_dir="$(backup_require_env BACKUP_DIR)"
  status_dir="${BACKUP_STATUS_DIR:-${backup_dir}/status}"
  backup_validate_dir "${status_dir}"
  backup_lock_or_exit "${backup_dir}/.scheduler.lock"

  enabled="$(config_value 'backup.schedule_enabled' 'true')"
  hour="$(config_value 'backup.full_hour' '4')"
  minute="$(config_value 'backup.full_minute' '30')"
  interval="$(config_value 'backup.binlog_interval_minutes' '1')"
  [[ "${enabled}" == true || "${enabled}" == false ]] || { backup_error 'backup.schedule_enabled 必须为 true 或 false'; exit 1; }
  [[ "${hour}" =~ ^[0-9]+$ && "${hour}" -le 23 && "${minute}" =~ ^[0-9]+$ && "${minute}" -le 59 ]] || {
    backup_error '备份全量时间配置无效'
    exit 1
  }
  [[ "${interval}" =~ ^[0-9]+$ && "${interval}" -ge 1 && "${interval}" -le 5 ]] || {
    backup_error 'binlog 归档间隔必须为 1-5 分钟'
    exit 1
  }
  if [[ "${enabled}" == false ]]; then
    "${SCRIPT_DIR}/backup-status.sh" write || true
    exit 0
  fi

  now_hour="$((10#$(date +%H)))"
  now_minute="$((10#$(date +%M)))"
  if ((now_minute % interval == 0)); then
    run_job "${status_dir}" binlog "${SCRIPT_DIR}/archive-binlog.sh" archive
  fi
  if ((now_hour == hour && now_minute == minute)); then
    run_job "${status_dir}" full "${SCRIPT_DIR}/backup-online.sh" full
  fi
  "${SCRIPT_DIR}/backup-status.sh" write || true
}

main "$@"