{
  "QueryLanguage": "JSONata",
  "StartAt": "ReserveInventory",
  "States": {
    "ReserveInventory": {
      "Type": "Task",
      "Resource": "arn:aws:states:::dynamodb:updateItem",
      "Arguments": {
        "TableName": "InventoryTable",
        "Key": {
          "productId": {
            "S": "{% $states.input.productId %}"
          }
        },
        "UpdateExpression": "SET reserved = reserved + :qty",
        "ExpressionAttributeValues": {
          ":qty": {
            "N": "{% $string($states.input.quantity) %}"
          }
        }
      },
      "Assign": {
        "orderId": "{% $states.input.orderId %}",
        "productId": "{% $states.input.productId %}",
        "reservedQty": "{% $states.input.quantity %}",
        "total": "{% $states.input.total %}"
      },
      "Catch": [
        {
          "ErrorEquals": [
            "States.ALL"
          ],
          "Assign": {
            "orderId": "{% $states.input.orderId %}",
            "failedStep": "ReserveInventory",
            "errorInfo": "{% $states.errorOutput %}"
          },
          "Next": "OrderFailed"
        }
      ],
      "Next": "ChargePayment"
    },
    "ChargePayment": {
      "Type": "Task",
      "Resource": "arn:aws:states:::lambda:invoke",
      "Arguments": {
        "FunctionName": "arn:aws:lambda:us-east-1:123456789012:function:ChargeCard:$LATEST",
        "Payload": {
          "orderId": "{% $orderId %}",
          "amount": "{% $total %}"
        }
      },
      "Assign": {
        "chargeId": "{% $states.result.Payload.chargeId %}"
      },
      "Output": "{% $states.result.Payload %}",
      "Catch": [
        {
          "ErrorEquals": [
            "States.ALL"
          ],
          "Assign": {
            "failedStep": "ChargePayment",
            "errorInfo": "{% $states.errorOutput %}"
          },
          "Next": "ReleaseInventory"
        }
      ],
      "Next": "ShipOrder"
    },
    "ShipOrder": {
      "Type": "Task",
      "Resource": "arn:aws:states:::lambda:invoke",
      "Arguments": {
        "FunctionName": "arn:aws:lambda:us-east-1:123456789012:function:ShipOrder:$LATEST",
        "Payload": {
          "orderId": "{% $orderId %}"
        }
      },
      "Catch": [
        {
          "ErrorEquals": [
            "States.ALL"
          ],
          "Assign": {
            "failedStep": "ShipOrder",
            "errorInfo": "{% $states.errorOutput %}"
          },
          "Next": "RefundPayment"
        }
      ],
      "Next": "OrderComplete"
    },
    "RefundPayment": {
      "Type": "Task",
      "Resource": "arn:aws:states:::lambda:invoke",
      "Arguments": {
        "FunctionName": "arn:aws:lambda:us-east-1:123456789012:function:RefundCharge:$LATEST",
        "Payload": {
          "chargeId": "{% $chargeId %}",
          "reason": "{% $errorInfo.Cause %}"
        }
      },
      "Next": "ReleaseInventory"
    },
    "ReleaseInventory": {
      "Type": "Task",
      "Resource": "arn:aws:states:::dynamodb:updateItem",
      "Arguments": {
        "TableName": "InventoryTable",
        "Key": {
          "productId": {
            "S": "{% $productId %}"
          }
        },
        "UpdateExpression": "SET reserved = reserved - :qty",
        "ExpressionAttributeValues": {
          ":qty": {
            "N": "{% $string($reservedQty) %}"
          }
        }
      },
      "Next": "OrderFailed"
    },
    "OrderFailed": {
      "Type": "Fail",
      "Error": "{% $failedStep & 'Error' %}",
      "Cause": "{% 'Order ' & $orderId & ' failed at ' & $failedStep & ': ' & ($exists($errorInfo.Cause) ? $errorInfo.Cause : 'Unknown') %}"
    },
    "OrderComplete": {
      "Type": "Succeed"
    }
  }
}