// npm
import * as AWS from 'aws-sdk';
import * as _ from 'lodash';
import * as assert from 'assert';

// app
import { config, log } from '../../config';

export async function flushDynamoDBTable(): Promise<void|never> {
  const dynamoDBClient: AWS.DynamoDB.DocumentClient = new AWS.DynamoDB.DocumentClient({
    region: config.cacheDynamo.region,
    endpoint: config.cacheDynamo.endpoint,
  });

  const input: AWS.DynamoDB.DocumentClient.ScanInput = {
    TableName: config.cacheDynamo.tableName as string,
  };

  /* eslint-disable no-await-in-loop */
  do {
    const output: AWS.DynamoDB.DocumentClient.ScanOutput = await dynamoDBClient.scan(input).promise();
    input.ExclusiveStartKey = output.LastEvaluatedKey;
    for (const item of output.Items as AWS.DynamoDB.DocumentClient.ItemList) {
      await dynamoDBClient.delete({
        TableName: config.cacheDynamo.tableName as string,
        Key: _.pick(item, ['pk', 'sk']),
        ReturnValues: 'NONE',
        ReturnConsumedCapacity: 'NONE',
        ReturnItemCollectionMetrics: 'NONE',
      }).promise();
    }
  } while (input.ExclusiveStartKey != null);
  /* eslint-enable no-await-in-loop */
}

export async function ensureTestDynamoDBTable(): Promise<void> {
  const dynamoDBInstance = new AWS.DynamoDB({
    region: config.cacheDynamo.region,
    endpoint: config.cacheDynamo.endpoint,
  });

  try {
    await dynamoDBInstance.createTable({
      TableName: config.cacheDynamo.tableName as string,
      BillingMode: 'PAY_PER_REQUEST',
      ProvisionedThroughput: {
        ReadCapacityUnits: 5,
        WriteCapacityUnits: 5,
      },
      LocalSecondaryIndexes: [
        {
          IndexName: 'pk_score',
          Projection: {
            ProjectionType: 'ALL',
          },
          KeySchema: [
            {
              KeyType: 'HASH',
              AttributeName: 'pk',
            },
            {
              KeyType: 'RANGE',
              AttributeName: 'score',
            },
          ],
        },
      ],
      AttributeDefinitions: [
        {
          AttributeName: 'pk',
          AttributeType: 'S',
        },
        {
          AttributeName: 'score',
          AttributeType: 'N',
        },
        {
          AttributeName: 'sk',
          AttributeType: 'S',
        },
      ],
      KeySchema: [
        {
          KeyType: 'HASH',
          AttributeName: 'pk',
        },
        {
          KeyType: 'RANGE',
          AttributeName: 'sk',
        },
      ],
    }).promise();
  } catch (error) {
    if ((error as AWS.AWSError).code !== 'ResourceInUseException') {
      log.debug(error);
      assert.fail('Cannot create LocalStack DynamoDB Table');
    }
  }
}