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

# 现场临时热替换 syslog-consumer-rule 容器内的 JAR。
# 默认容器名和容器内路径来自当前生产镜像：
#   syslog-consumer-rule-dm:/app/syslog-consumer-rule.jar
#
# 用法：
#   ./upgrade-doc/replace-syslog-consumer-rule-jar.sh
#   ./upgrade-doc/replace-syslog-consumer-rule-jar.sh /path/to/syslog-consumer-rule-1.0.0.jar

CONTAINER_NAME="syslog-consumer-rule-dm"
CONTAINER_JAR="/app/syslog-consumer-rule.jar"

SCRIPT_DIR=$(cd "$(dirname "${BASH_SOURCE[0]}")" && pwd)
PROJECT_DIR=$(cd "${SCRIPT_DIR}/.." && pwd)
DEFAULT_JAR="${PROJECT_DIR}/syslog-consumer-rule/target/syslog-consumer-rule-1.0.0.jar"
LOCAL_JAR="${1:-${DEFAULT_JAR}}"
BACKUP_DIR="${SCRIPT_DIR}/backups"
BACKUP_JAR="${BACKUP_DIR}/syslog-consumer-rule-$(date '+%Y%m%d-%H%M%S').jar"
STARTED_AT=""

fail() {
  echo "ERROR: $*" >&2
  exit 1
}

command -v docker >/dev/null 2>&1 || fail "未找到 docker 命令"
[[ -f "${LOCAL_JAR}" && -s "${LOCAL_JAR}" ]] || fail "新 JAR 不存在或为空: ${LOCAL_JAR}"
docker inspect "${CONTAINER_NAME}" >/dev/null 2>&1 || fail "容器不存在: ${CONTAINER_NAME}"

mkdir -p "${BACKUP_DIR}"

echo "[1/5] 备份容器内旧 JAR"
docker cp "${CONTAINER_NAME}:${CONTAINER_JAR}" "${BACKUP_JAR}"
echo "旧 JAR 已备份到: ${BACKUP_JAR}"

echo "[2/5] 停止容器 ${CONTAINER_NAME}"
docker stop "${CONTAINER_NAME}" >/dev/null

restart_after_failure() {
  local exit_code=$?
  if [[ ${exit_code} -ne 0 ]]; then
    echo "替换过程失败，尝试重新启动容器。旧 JAR 备份位于: ${BACKUP_JAR}" >&2
    docker start "${CONTAINER_NAME}" >/dev/null 2>&1 || true
  fi
  exit "${exit_code}"
}
trap restart_after_failure ERR

echo "[3/5] 替换容器内 JAR"
docker cp "${LOCAL_JAR}" "${CONTAINER_NAME}:${CONTAINER_JAR}"

echo "[4/5] 启动容器"
STARTED_AT=$(date -u '+%Y-%m-%dT%H:%M:%SZ')
docker start "${CONTAINER_NAME}" >/dev/null
sleep 8

RUNNING=$(docker inspect --format '{{.State.Running}}' "${CONTAINER_NAME}")
if [[ "${RUNNING}" != "true" ]]; then
  trap - ERR
  echo "ERROR: 容器启动后未保持运行，启动日志如下：" >&2
  docker logs --since "${STARTED_AT}" "${CONTAINER_NAME}" 2>&1 | tail -80 >&2 || true
  echo "可使用以下命令回滚：" >&2
  echo "docker cp '${BACKUP_JAR}' '${CONTAINER_NAME}:${CONTAINER_JAR}' && docker start '${CONTAINER_NAME}'" >&2
  exit 1
fi

trap - ERR

echo "[5/5] 替换完成，显示本次启动日志"
echo "新 JAR: ${LOCAL_JAR}"
echo "旧 JAR 备份: ${BACKUP_JAR}"
echo "注意：以后若删除或重新创建容器，容器内替换会丢失，仍需更新镜像。"
docker logs --since "${STARTED_AT}" "${CONTAINER_NAME}" 2>&1 | tail -80