cloudfoundry/stratos

import { Store } from '@ngrx/store';
import { map } from 'rxjs/operators';

import { CFAppState } from '../../../../../../../cloud-foundry/src/cf-app-state';
import {
  ListDataSource,
} from '../../../../../../../core/src/shared/components/list/data-sources-controllers/list-data-source';
import { IListConfig } from '../../../../../../../core/src/shared/components/list/list.component.types';
import { IMetricMatrixResult, IMetrics } from '../../../../../../../store/src/types/base-metric.types';
import { IMetricCell } from '../../../../../../../store/src/types/metric.types';
import { FetchCFCellMetricsPaginatedAction } from '../../../../../actions/cf-metrics.actions';
import { cfEntityFactory } from '../../../../../cf-entity-factory';

export interface CfCellHealthEntry {
  timestamp: number;
  state: CfCellHealthState;
}

export enum CfCellHealthState {
  HEALTHY = 0,
  UNHEALTHY = 1,
  INITIAL_HEALTHY = 2,
  INITIAL_UNHEALTHY = 3,
}

export class CfCellHealthDataSource extends ListDataSource<CfCellHealthEntry, IMetrics<IMetricMatrixResult<IMetricCell>>> {

  static appIdPath = 'metric.application_id';

  constructor(
    store: Store<CFAppState>,
    listConfig: IListConfig<CfCellHealthEntry>,
    action: FetchCFCellMetricsPaginatedAction,
  ) {
    super({
      store,
      action,
      schema: cfEntityFactory(action.entityType),
      getRowUniqueId: (row: CfCellHealthEntry) => row.timestamp.toString(),
      paginationKey: action.paginationKey,
      isLocal: true,
      transformEntity: map((response) => {
        if (!response || !response[0] || !response[0].data.result[0] || !response[0].data.result[0].values) {
          return [];
        }
        return this.mapMetricsToStates(response[0].data.result[0].values);
      }),
      listConfig
    });
  }

  private mapMetricsToStates(values: [number, string][]): CfCellHealthEntry[] {
    // Create a new collection containing only the change of state
    const newValues = values.reduce((res, value, index) => {
      const timestamp = value['0'];
      const state = value['1'];
      if (index === 0) {
        // Record the first entry
        res.current = state;
        res.collection.push({
          timestamp,
          state: state === '0' ? CfCellHealthState.INITIAL_HEALTHY : CfCellHealthState.INITIAL_UNHEALTHY
        });
      } else if (res.current !== state) {
        // Record any change of state
        res.current = state;
        res.collection.push({
          timestamp,
          state: state === '0' ? CfCellHealthState.HEALTHY : CfCellHealthState.UNHEALTHY
        });
      }
      return res;
    }, { current: null, collection: [] });

    return newValues.collection;
  }

}