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

# 生成供后台只读展示的备份状态摘要。内容不包含密钥、备份载荷或下载地址。

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

json_escape() {
  local value="$1"
  value="${value//\\/\\\\}"
  value="${value//\"/\\\"}"
  value="${value//$'\n'/ }"
  value="${value//$'\r'/ }"
  printf '%s' "${value}"
}

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_status() {
  backup_require_cmd docker
  backup_require_cmd ossutil

  local backup_dir oss_uri status_dir status_file temp_file enabled hour minute interval
  local local_complete remote_complete binlog_state binlog_file binlog_remote job_type job_status job_at job_message health
  backup_dir="$(backup_require_env BACKUP_DIR)"
  oss_uri="$(backup_require_env BACKUP_OSS_URI)"
  status_dir="${BACKUP_STATUS_DIR:-${backup_dir}/status}"
  backup_validate_dir "${status_dir}"
  mkdir -p "${status_dir}"
  chmod 700 "${status_dir}"
  status_file="${status_dir}/status.json"
  temp_file="${status_dir}/.status-$$.json"

  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')"
  local_complete="$(find "${backup_dir}/full/daily" -name complete.env -type f -print 2>/dev/null | sort | tail -1 || true)"
  remote_complete="$(ossutil ls "${oss_uri}/mysql/full/daily/" -r 2>/dev/null | awk '$NF ~ /\/complete\.env$/ { latest = $NF } END { print latest }')"
  binlog_state="$(find "${backup_dir}/binlog-state" -name last-archived.env -type f -print 2>/dev/null | sort | tail -1 || true)"
  binlog_file=''
  binlog_remote=''
  if [[ -n "${binlog_state}" ]]; then
    binlog_file="$(awk -F= '$1 == "filename" { print substr($0, index($0, "=") + 1); exit }' "${binlog_state}")"
    binlog_remote="$(awk -F= '$1 == "remote_dir" { print substr($0, index($0, "=") + 1); exit }' "${binlog_state}")"
  fi

  job_type=''
  job_status=''
  job_at=''
  job_message=''
  if [[ -f "${status_dir}/last-job.env" ]]; then
    # shellcheck disable=SC1090
    source "${status_dir}/last-job.env"
  fi
  if [[ "${job_status}" == 'failed' ]]; then
    health='warning'
  elif [[ -n "${local_complete}" && -n "${remote_complete}" && -n "${binlog_file}" ]]; then
    health='healthy'
  else
    health='warning'
  fi

  cat > "${temp_file}" <<EOF
{
  "generated_at": "$(date -Iseconds)",
  "health": "$(json_escape "${health}")",
  "schedule": {
    "enabled": "$(json_escape "${enabled}")",
    "full_hour": "$(json_escape "${hour}")",
    "full_minute": "$(json_escape "${minute}")",
    "binlog_interval_minutes": "$(json_escape "${interval}")"
  },
  "last_full": {
    "local_complete": "$(json_escape "${local_complete}")",
    "remote_complete": "$(json_escape "${remote_complete}")"
  },
  "last_binlog": {
    "file": "$(json_escape "${binlog_file}")",
    "remote_dir": "$(json_escape "${binlog_remote}")"
  },
  "last_job": {
    "type": "$(json_escape "${job_type}")",
    "status": "$(json_escape "${job_status}")",
    "at": "$(json_escape "${job_at}")",
    "message": "$(json_escape "${job_message}")"
  }
}
EOF
  chmod 640 "${temp_file}"
  mv "${temp_file}" "${status_file}"
}

case "${1:-write}" in
  write) write_status ;;
  *)
    printf '用法: %s {write}\n' "$0" >&2
    exit 1
    ;;
esac