#!/bin/bash

# 获取所有可用的 region
regions=$(aws ec2 describe-regions --query 'Regions[*].RegionName' --output text)
# regions=ap-south-1

for region in $regions; do
    echo "=== Processing region: $region ==="

    # 获取当前 region 的实例 ID 列表
    instance_ids=$(aws ec2 describe-instances \
        --region $region \
        --query 'Reservations[*].Instances[*].InstanceId' \
        --output text)

    for instance_id in $instance_ids; do
        echo "---- Instance: $instance_id ----"

        # 获取该实例的全部 EBS block device mapping
        devices=$(aws ec2 describe-instances \
            --region $region \
            --instance-ids $instance_id \
            --query 'Reservations[0].Instances[0].BlockDeviceMappings[*].DeviceName' \
            --output text)

        for device in $devices; do
            echo "Setting DeleteOnTermination=false for $instance_id ($device)"

            # 创建临时 JSON 文件
            tmpfile=$(mktemp)

            cat > $tmpfile <<EOF
[
  {
    "DeviceName": "$device",
    "Ebs": {
      "DeleteOnTermination": false
    }
  }
]
EOF

            # 修改属性
            aws ec2 modify-instance-attribute \
                --region $region \
                --instance-id $instance_id \
                --block-device-mappings file://$tmpfile

            rm -f $tmpfile
        done
    done
done

echo "All instances processed."