#!/bin/bash

# 检查参数是否提供
if [ $# -ne 3 ]; then
  echo "用法: $0 <虚机名称> <节点名称> <备份路径>"
  echo "示例: $0 emma es-node1 /backups"
  exit 1
fi

VM_NAME=$1                                           # 虚机名称，例如 "emma"
NODE_NAME=$2                                         # ES节点名称，例如 "es-node1"
BACKUP_DIR=$3                                        # 备份路径，例如 "/backups"
BACKUP_FILE="${BACKUP_DIR}/${VM_NAME}-backup.tar.gz" # 最新备份文件名
ES_HOST="elastic.k8s.xunlang.home"                   # ES集群地址，根据实际环境修改

# 确保备份目录存在
if [ ! -d "$BACKUP_DIR" ]; then
  echo "创建备份目录: $BACKUP_DIR"
  mkdir -p "$BACKUP_DIR"
fi

# 定义函数：重新启用ES集群分片分配
enable_shard_allocation() {
  echo "重新启用ES集群分片分配..."
  curl -X PUT "http://${ES_HOST}/_cluster/settings" -H 'Content-Type: application/json' -d'{
      "persistent": {
          "cluster.routing.allocation.enable": "all"
      }
  }'
  if [ $? -ne 0 ]; then
    echo "警告: 重新启用ES集群分片分配失败"
  else
    echo "ES集群分片分配已成功重新启用"
  fi
}

# 定义函数：禁用ES集群分片分配
disable_shard_allocation() {
  echo "禁用ES集群分片分配..."
  curl -u elastic:your_secure_password -X PUT "http://${ES_HOST}/_cluster/settings" -H 'Content-Type: application/json' -d'{
      "persistent": {
          "cluster.routing.allocation.enable": "none"
      }
  }'
  if [ $? -ne 0 ]; then
    echo "错误: 禁用ES集群分片分配失败"
    enable_shard_allocation
    exit 1
  fi
  echo ""
}

# 定义函数：停止虚机
stop_vm() {
  echo "停止虚机: $VM_NAME..."
  lxc stop "$VM_NAME"
  if [ $? -ne 0 ]; then
    echo "错误: 无法停止虚机 $VM_NAME"
    enable_shard_allocation
    exit 1
  fi
}

# 定义函数：管理备份文件
manage_backup_files() {
  echo "管理备份文件..."
  if [ -f "${BACKUP_FILE}_bak1" ]; then
    mv "${BACKUP_FILE}_bak1" "${BACKUP_FILE}_bak2"
  fi
  if [ -f "$BACKUP_FILE" ]; then
    mv "$BACKUP_FILE" "${BACKUP_FILE}_bak1"
  fi
}

# 定义函数：执行备份
perform_backup() {
  echo "开始备份虚机 $VM_NAME 到 $BACKUP_FILE..."
  lxc export "$VM_NAME" "$BACKUP_FILE"
  if [ $? -ne 0 ]; then
    echo "错误: 备份失败"
    lxc start "$VM_NAME" # 备份失败时尝试重启虚机
    enable_shard_allocation
    exit 1
  fi
}

# 定义函数：重启虚机
start_vm() {
  echo "重启虚机: $VM_NAME..."
  lxc start "$VM_NAME"
  if [ $? -ne 0 ]; then
    echo "错误: 无法启动虚机 $VM_NAME"
    enable_shard_allocation
    exit 1
  fi
}

# 定义函数：等待节点加入ES集群
wait_for_node_join() {
  echo "等待节点 $NODE_NAME 加入ES集群..."
  MAX_WAIT=60     # 最大等待时间（秒）
  WAIT_INTERVAL=5 # 检查间隔（秒）
  ELAPSED=0
  while [ $ELAPSED -lt $MAX_WAIT ]; do
    NODE_COUNT=$(curl -s "http://${ES_HOST}/_cat/nodes" | grep -c "$NODE_NAME")
    if [ "$NODE_COUNT" -ge 1 ]; then
      echo "节点 $NODE_NAME 已加入集群"
      return 0
    fi
    sleep $WAIT_INTERVAL
    ELAPSED=$((ELAPSED + WAIT_INTERVAL))
  done
  echo "警告: 等待超时，节点 $NODE_NAME 未及时加入集群"
  enable_shard_allocation
  exit 1
}

# 主流程
disable_shard_allocation
stop_vm
manage_backup_files
perform_backup
start_vm
wait_for_node_join
enable_shard_allocation

echo "备份完成！最新备份文件: $BACKUP_FILE"