/*
 * © 2021 Thoughtworks, Inc.
 */

import { mockClient } from 'aws-sdk-client-mock'
import { CloudWatchLogsClient } from '@aws-sdk/client-cloudwatch-logs'
import {
  CloudWatchClient,
  GetMetricDataCommand,
  GetMetricDataCommandInput,
  GetMetricDataCommandOutput,
} from '@aws-sdk/client-cloudwatch'
import {
  CostExplorerClient,
  GetCostAndUsageCommand,
  GetCostAndUsageRequest,
  GetRightsizingRecommendationCommand,
  GetRightsizingRecommendationRequest,
} from '@aws-sdk/client-cost-explorer'
import { S3Client } from '@aws-sdk/client-s3'
import {
  AthenaClient,
  GetQueryResultsCommand,
  GetQueryResultsOutput,
} from '@aws-sdk/client-athena'
import { GetTableCommand, GlueClient } from '@aws-sdk/client-glue'
import { ServiceWrapper } from '../lib'

const startDate = '2020-08-06'
const endDate = '2020-08-07'

const cloudWatchMock = mockClient(CloudWatchClient)
const costExplorerMock = mockClient(CostExplorerClient)
const athenaMock = mockClient(AthenaClient)
const glueMock = mockClient(GlueClient)

beforeEach(() => {
  costExplorerMock.reset()
  cloudWatchMock.reset()
  athenaMock.reset()
  glueMock.reset()
})

describe('aws service helper', () => {
  afterEach(() => {
    jest.restoreAllMocks()
  })

  const getServiceWrapper = () =>
    new ServiceWrapper(
      new CloudWatchClient(),
      new CloudWatchLogsClient(),
      new CostExplorerClient(),
      new S3Client(),
      new AthenaClient(),
      new GlueClient(),
    )

  it('enablePagination decorator should follow CostExplorer CostAndUsage next pages', async () => {
    const costExplorerGetCostAndUsageSpy = jest.fn()
    const firstPageResponse = buildAwsCostExplorerGetCostAndUsageResponse(
      [
        {
          start: startDate,
          value: '1.2120679',
          types: ['EBS:VolumeUsage.gp2'],
        },
      ],
      'tokenToNextPage',
    )
    const secondPageResponse = buildAwsCostExplorerGetCostAndUsageResponse(
      [
        {
          start: startDate,
          value: '1.2120679',
          types: ['EBS:VolumeUsage.gp2'],
        },
      ],
      null,
    )
    const getCostAndUsageRequest = buildAwsCostExplorerGetCostAndUsageRequest()
    costExplorerGetCostAndUsageSpy
      .mockResolvedValueOnce(firstPageResponse)
      .mockResolvedValueOnce(secondPageResponse)

    costExplorerMock
      .on(GetCostAndUsageCommand)
      .callsFake(costExplorerGetCostAndUsageSpy)

    const responses = await getServiceWrapper().getCostAndUsageResponses(
      getCostAndUsageRequest,
    )

    expect(costExplorerGetCostAndUsageSpy).toHaveBeenNthCalledWith(
      1,
      getCostAndUsageRequest,
      expect.anything(),
    )
    getCostAndUsageRequest.NextPageToken = 'tokenToNextPage'
    expect(costExplorerGetCostAndUsageSpy).toHaveBeenNthCalledWith(
      2,
      getCostAndUsageRequest,
      expect.anything(),
    )

    expect(responses).toEqual([firstPageResponse, secondPageResponse])
  })

  it('enablePagination decorator should follow CostExplorer Rightsizing Recommendation next pages', async () => {
    const costExplorerGetRightsizingRecommendationsSpy = jest.fn()
    const firstPageResponse =
      buildAwsCostExplorerGetRightsizingRecommendationsResponse(
        [
          {
            type: 'Terminate',
            instanceType: 't2.nano',
            savings: '200',
          },
        ],
        'tokenToNextPage',
      )
    const secondPageResponse =
      buildAwsCostExplorerGetRightsizingRecommendationsResponse(
        [
          {
            type: 'Terminate',
            instanceType: 't2.micro',
            savings: '300',
          },
        ],
        null,
      )
    const getRightsizingRecommendationsRequest =
      buildAwsCostExplorerGetRightsizingRecommendationsRequest()
    costExplorerGetRightsizingRecommendationsSpy
      .mockResolvedValueOnce(firstPageResponse)
      .mockResolvedValueOnce(secondPageResponse)

    costExplorerMock
      .on(GetRightsizingRecommendationCommand)
      .callsFake(costExplorerGetRightsizingRecommendationsSpy)

    const responses =
      await getServiceWrapper().getRightsizingRecommendationsResponses(
        getRightsizingRecommendationsRequest,
      )

    expect(
      costExplorerGetRightsizingRecommendationsSpy,
    ).toHaveBeenNthCalledWith(
      1,
      getRightsizingRecommendationsRequest,
      expect.anything(),
    )
    getRightsizingRecommendationsRequest.NextPageToken = 'tokenToNextPage'
    expect(
      costExplorerGetRightsizingRecommendationsSpy,
    ).toHaveBeenNthCalledWith(
      2,
      getRightsizingRecommendationsRequest,
      expect.anything(),
    )

    expect(responses).toEqual([firstPageResponse, secondPageResponse])
  })

  it('enablePagination decorator should follow CloudWatch next pages', async () => {
    const firstPageResponse =
      buildAwsCloudWatchGetMetricDataResponse('tokenToNextPage')
    const secondPageResponse = buildAwsCloudWatchGetMetricDataResponse(null)
    const metricDataRequest = buildAwsCloudWatchGetMetricDataRequest()

    const cloudWatchGetMetricDataSpy = jest.fn()
    cloudWatchGetMetricDataSpy
      .mockResolvedValueOnce(firstPageResponse)
      .mockResolvedValueOnce(secondPageResponse)

    cloudWatchMock
      .on(GetMetricDataCommand)
      .callsFake(cloudWatchGetMetricDataSpy)

    const responses = await getServiceWrapper().getMetricDataResponses(
      buildAwsCloudWatchGetMetricDataRequest(),
    )

    expect(cloudWatchGetMetricDataSpy).toHaveBeenNthCalledWith(
      1,
      metricDataRequest,
      expect.anything(),
    )
    metricDataRequest.NextToken = 'tokenToNextPage'
    expect(cloudWatchGetMetricDataSpy).toHaveBeenNthCalledWith(
      2,
      metricDataRequest,
      expect.anything(),
    )
    expect(responses).toEqual([firstPageResponse, secondPageResponse])
  })

  it('enablePagination decorator should follow Athena next pages', async () => {
    const firstPageResponse =
      buildAthenaGetQueryResultsResponse('tokenToNextPage')
    const secondPageResponse = buildAthenaGetQueryResultsResponse(null)

    const athenaGetResultsSpy = jest.fn()
    athenaGetResultsSpy
      .mockResolvedValueOnce(firstPageResponse)
      .mockResolvedValueOnce(secondPageResponse)
    athenaMock.on(GetQueryResultsCommand).callsFake(athenaGetResultsSpy)

    const responses = await getServiceWrapper().getAthenaQueryResultSets({
      QueryExecutionId: 'some-query-id',
    })

    expect(athenaGetResultsSpy).toHaveBeenNthCalledWith(
      1,
      { QueryExecutionId: 'some-query-id' },
      expect.anything(),
    )
    expect(athenaGetResultsSpy).toHaveBeenNthCalledWith(
      2,
      {
        QueryExecutionId: 'some-query-id',
        NextToken: 'tokenToNextPage',
      },
      expect.anything(),
    )

    expect(responses).toEqual([firstPageResponse, secondPageResponse])
  })

  it('should query AWS Glue Data Catalog for the description of a given Athena table ', async () => {
    const glueGetTableSpy = jest.fn()
    const mockTableDetails = {
      Table: {
        StorageDescriptor: {
          Columns: [
            {
              Name: 'column1',
              Type: 'string',
            },
            {
              Name: 'column2',
              Type: 'string',
            },
          ],
        },
      },
    }
    glueGetTableSpy.mockResolvedValueOnce(mockTableDetails)
    glueMock.on(GetTableCommand).callsFake(glueGetTableSpy)

    const params = {
      DatabaseName: 'database-name',
      Name: 'table-name',
    }

    const result = await getServiceWrapper().getAthenaTableDescription(params)

    expect(glueGetTableSpy).toHaveBeenCalledWith(params, expect.anything())
    expect(result).toEqual(mockTableDetails)
  })
})

function buildAwsCostExplorerGetRightsizingRecommendationsRequest(): GetRightsizingRecommendationRequest {
  return {
    Service: 'AmazonEC2',
    Configuration: {
      BenefitsConsidered: false,
      RecommendationTarget: 'SAME_INSTANCE_FAMILY',
    },
  }
}

function buildAwsCostExplorerGetRightsizingRecommendationsResponse(
  data: { type: string; instanceType: string; savings: string }[],
  nextPageToken: string,
) {
  return {
    Metadata: {
      RecommendationId: '',
      GenerationTimestamp: '',
      LookbackPeriodInDays: '14',
    },
    Summary: {
      TotalRecommendationCount: '',
      EstimatedTotalMonthlySavingsAmount: '',
      SavingsCurrencyCode: 'USD',
      SavingsPercentage: '',
    },
    RightsizingRecommendations: data.map(({ type, instanceType, savings }) => {
      return {
        AccountId: '',
        CurrentInstance: {
          ResourceId: '',
          InstanceName: '',
          Tags: [
            {
              Key: 'aws:createdBy',
              Values: [''],
            },
            { Key: 'user:Name', Values: [''] },
          ],
          ResourceDetails: {
            EC2ResourceDetails: {
              HourlyOnDemandRate: '',
              InstanceType: instanceType,
              Platform: 'Red Hat Enterprise Linux',
              Region: 'Asia Pacific (Mumbai)',
              Sku: '',
              Memory: '1 GiB',
              NetworkPerformance: 'Low to Moderate',
              Storage: 'EBS only',
              Vcpu: '1',
            },
          },
          ResourceUtilization: {
            EC2ResourceUtilization: {
              MaxCpuUtilizationPercentage: '',
              MaxMemoryUtilizationPercentage: '',
              MaxStorageUtilizationPercentage: '',
              EBSResourceUtilization: {
                EbsReadOpsPerSecond: '',
                EbsWriteOpsPerSecond: '',
                EbsReadBytesPerSecond: '',
                EbsWriteBytesPerSecond: '',
              },
            },
          },
          ReservationCoveredHoursInLookbackPeriod: '',
          SavingsPlansCoveredHoursInLookbackPeriod: '',
          OnDemandHoursInLookbackPeriod: '',
          TotalRunningHoursInLookbackPeriod: '',
          MonthlyCost: '',
          CurrencyCode: 'USD',
        },
        RightsizingType: type,
        TerminateRecommendationDetail: {
          EstimatedMonthlySavings: savings,
          CurrencyCode: 'USD',
        },
      }
    }),
    Configuration: {
      RecommendationTarget: 'SAME_INSTANCE_FAMILY',
      BenefitsConsidered: false,
    },
    NextPageToken: nextPageToken,
  }
}

function buildAwsCostExplorerGetCostAndUsageRequest(): GetCostAndUsageRequest {
  return {
    TimePeriod: {
      Start: startDate,
      End: endDate,
    },
    Granularity: 'DAILY',
    Metrics: [
      'AmortizedCost',
      'BlendedCost',
      'NetAmortizedCost',
      'NetUnblendedCost',
      'NormalizedUsageAmount',
      'UnblendedCost',
      'UsageQuantity',
    ],
    GroupBy: [
      {
        Key: 'USAGE_TYPE',
        Type: 'DIMENSION',
      },
    ],
  }
}

function buildAwsCostExplorerGetCostAndUsageResponse(
  data: { start: string; value: string; types: string[] }[],
  nextPageToken: string,
) {
  return {
    NextPageToken: nextPageToken,
    GroupDefinitions: [
      {
        Type: 'DIMENSION',
        Key: 'USAGE_TYPE',
      },
    ],
    ResultsByTime: data.map(({ start, value, types }) => {
      return {
        TimePeriod: {
          Start: start,
        },
        Groups: [
          {
            Keys: types,
            Metrics: { UsageQuantity: { Amount: value, Unit: 'GB-Month' } },
          },
        ],
      }
    }),
  }
}

function buildAwsCloudWatchGetMetricDataResponse(
  nextPageToken: string,
): GetMetricDataCommandOutput {
  return {
    $metadata: {},
    NextToken: nextPageToken,
    MetricDataResults: [
      {
        Id: 'cpuUtilization',
        Label: 'AWS/ElastiCache CPUUtilization',
        Timestamps: [new Date(startDate), new Date(endDate)],
        Values: [1.0456, 2.03242],
        StatusCode: 'Complete',
        Messages: [],
      },
    ],
  }
}

function buildAwsCloudWatchGetMetricDataRequest(): GetMetricDataCommandInput {
  return {
    StartTime: new Date(startDate),
    EndTime: new Date(endDate),
    MetricDataQueries: [
      {
        Id: 'cpuUtilizationWithEmptyValues',
        Expression:
          "SEARCH('{AWS/ElastiCache} MetricName=\"CPUUtilization\"', 'Average', 3600)",
        ReturnData: false,
      },
      {
        Id: 'cpuUtilization',
        Expression: 'REMOVE_EMPTY(cpuUtilizationWithEmptyValues)',
      },
    ],
    ScanBy: 'TimestampAscending',
  }
}

function buildAthenaGetQueryResultsResponse(
  nextPageToken: string,
): GetQueryResultsOutput {
  return {
    NextToken: nextPageToken,
    ResultSet: { Rows: [] },
  }
}