import {
  AppEvents,
  applyFieldOverrides,
  arrowTableToDataFrame,
  base64StringToArrowTable,
  DataSourceApi,
  dateMath,
} from '@grafana/data';
import { config, getBackendSrv, getDataSourceSrv } from '@grafana/runtime';
import { appEvents } from 'app/core/core';
import { updateLocation } from 'app/core/actions';
import store from 'app/core/store';
import {
  ALERT_DEFINITION_UI_STATE_STORAGE_KEY,
  cleanUpState,
  loadAlertRules,
  loadedAlertRules,
  notificationChannelLoaded,
  setAlertDefinition,
  setAlertDefinitions,
  setInstanceData,
  setNotificationChannels,
  setQueryOptions,
  setUiState,
  updateAlertDefinitionOptions,
} from './reducers';
import {
  AlertDefinition,
  AlertDefinitionState,
  AlertDefinitionUiState,
  AlertRuleDTO,
  NotifierDTO,
  QueryGroupDataSource,
  QueryGroupOptions,
  ThunkResult,
} from 'app/types';
import { ExpressionDatasourceID } from '../../expressions/ExpressionDatasource';
import { ExpressionQuery } from '../../expressions/types';

export function getAlertRulesAsync(options: { state: string }): ThunkResult<void> {
  return async (dispatch) => {
    dispatch(loadAlertRules());
    const rules: AlertRuleDTO[] = await getBackendSrv().get('/api/alerts', options);

    if (config.featureToggles.ngalert) {
      const ngAlertDefinitions = await getBackendSrv().get('/api/alert-definitions');
      dispatch(setAlertDefinitions(ngAlertDefinitions.results));
    }

    dispatch(loadedAlertRules(rules));
  };
}

export function togglePauseAlertRule(id: number, options: { paused: boolean }): ThunkResult<void> {
  return async (dispatch, getState) => {
    await getBackendSrv().post(`/api/alerts/${id}/pause`, options);
    const stateFilter = getState().location.query.state || 'all';
    dispatch(getAlertRulesAsync({ state: stateFilter.toString() }));
  };
}

export function createNotificationChannel(data: any): ThunkResult<void> {
  return async (dispatch) => {
    try {
      await getBackendSrv().post(`/api/alert-notifications`, data);
      appEvents.emit(AppEvents.alertSuccess, ['Notification created']);
      dispatch(updateLocation({ path: 'alerting/notifications' }));
    } catch (error) {
      appEvents.emit(AppEvents.alertError, [error.data.error]);
    }
  };
}

export function updateNotificationChannel(data: any): ThunkResult<void> {
  return async (dispatch) => {
    try {
      await getBackendSrv().put(`/api/alert-notifications/${data.id}`, data);
      appEvents.emit(AppEvents.alertSuccess, ['Notification updated']);
      dispatch(updateLocation({ path: 'alerting/notifications' }));
    } catch (error) {
      appEvents.emit(AppEvents.alertError, [error.data.error]);
    }
  };
}

export function testNotificationChannel(data: any): ThunkResult<void> {
  return async (dispatch, getState) => {
    const channel = getState().notificationChannel.notificationChannel;
    await getBackendSrv().post('/api/alert-notifications/test', { id: channel.id, ...data });
  };
}

export function loadNotificationTypes(): ThunkResult<void> {
  return async (dispatch) => {
    const alertNotifiers: NotifierDTO[] = await getBackendSrv().get(`/api/alert-notifiers`);

    const notificationTypes = alertNotifiers.sort((o1, o2) => {
      if (o1.name > o2.name) {
        return 1;
      }
      return -1;
    });

    dispatch(setNotificationChannels(notificationTypes));
  };
}

export function loadNotificationChannel(id: number): ThunkResult<void> {
  return async (dispatch) => {
    await dispatch(loadNotificationTypes());
    const notificationChannel = await getBackendSrv().get(`/api/alert-notifications/${id}`);
    dispatch(notificationChannelLoaded(notificationChannel));
  };
}

export function getAlertDefinition(id: string): ThunkResult<void> {
  return async (dispatch) => {
    const alertDefinition = await getBackendSrv().get(`/api/alert-definitions/${id}`);
    dispatch(setAlertDefinition(alertDefinition));
  };
}

export function createAlertDefinition(): ThunkResult<void> {
  return async (dispatch, getStore) => {
    const alertDefinition = await buildAlertDefinition(getStore().alertDefinition);

    await getBackendSrv().post(`/api/alert-definitions`, alertDefinition);
    appEvents.emit(AppEvents.alertSuccess, ['Alert definition created']);
    dispatch(updateLocation({ path: 'alerting/list' }));
  };
}

export function updateAlertDefinition(): ThunkResult<void> {
  return async (dispatch, getStore) => {
    const alertDefinition = await buildAlertDefinition(getStore().alertDefinition);

    const updatedAlertDefinition = await getBackendSrv().put(
      `/api/alert-definitions/${alertDefinition.uid}`,
      alertDefinition
    );
    appEvents.emit(AppEvents.alertSuccess, ['Alert definition updated']);
    dispatch(setAlertDefinition(updatedAlertDefinition));
  };
}

export function updateAlertDefinitionUiState(uiState: Partial<AlertDefinitionUiState>): ThunkResult<void> {
  return (dispatch, getStore) => {
    const nextState = { ...getStore().alertDefinition.uiState, ...uiState };
    dispatch(setUiState(nextState));

    try {
      store.setObject(ALERT_DEFINITION_UI_STATE_STORAGE_KEY, nextState);
    } catch (error) {
      console.error(error);
    }
  };
}

export function updateAlertDefinitionOption(alertDefinition: Partial<AlertDefinition>): ThunkResult<void> {
  return (dispatch) => {
    dispatch(updateAlertDefinitionOptions(alertDefinition));
  };
}

export function queryOptionsChange(queryOptions: QueryGroupOptions): ThunkResult<void> {
  return (dispatch) => {
    dispatch(setQueryOptions(queryOptions));
  };
}

export function onRunQueries(): ThunkResult<void> {
  return (dispatch, getStore) => {
    const { queryRunner, getQueryOptions } = getStore().alertDefinition;
    const timeRange = { from: 'now-1h', to: 'now' };
    const queryOptions = getQueryOptions();

    queryRunner!.run({
      // if the queryRunner is undefined here somethings very wrong so it's ok to throw an unhandled error
      timezone: 'browser',
      timeRange: { from: dateMath.parse(timeRange.from)!, to: dateMath.parse(timeRange.to)!, raw: timeRange },
      maxDataPoints: queryOptions.maxDataPoints ?? 100,
      minInterval: queryOptions.minInterval,
      queries: queryOptions.queries,
      datasource: queryOptions.dataSource.name!,
    });
  };
}

export function evaluateAlertDefinition(): ThunkResult<void> {
  return async (dispatch, getStore) => {
    const { alertDefinition } = getStore().alertDefinition;

    const response: { instances: string[] } = await getBackendSrv().get(
      `/api/alert-definitions/eval/${alertDefinition.uid}`
    );

    const handledResponse = handleBase64Response(response.instances);

    dispatch(setInstanceData(handledResponse));
    appEvents.emit(AppEvents.alertSuccess, ['Alert definition tested successfully']);
  };
}

export function evaluateNotSavedAlertDefinition(): ThunkResult<void> {
  return async (dispatch, getStore) => {
    const { alertDefinition, getQueryOptions } = getStore().alertDefinition;
    const defaultDataSource = await getDataSourceSrv().get(null);

    const response: { instances: string[] } = await getBackendSrv().post('/api/alert-definitions/eval', {
      condition: alertDefinition.condition,
      data: buildDataQueryModel(getQueryOptions(), defaultDataSource),
    });

    const handledResponse = handleBase64Response(response.instances);
    dispatch(setInstanceData(handledResponse));
    appEvents.emit(AppEvents.alertSuccess, ['Alert definition tested successfully']);
  };
}

export function cleanUpDefinitionState(): ThunkResult<void> {
  return (dispatch) => {
    dispatch(cleanUpState(undefined));
  };
}

async function buildAlertDefinition(state: AlertDefinitionState) {
  const queryOptions = state.getQueryOptions();
  const currentAlertDefinition = state.alertDefinition;
  const defaultDataSource = await getDataSourceSrv().get(null);

  return {
    ...currentAlertDefinition,
    data: buildDataQueryModel(queryOptions, defaultDataSource),
  };
}

function handleBase64Response(frames: string[]) {
  const dataFrames = frames.map((instance) => {
    const table = base64StringToArrowTable(instance);
    return arrowTableToDataFrame(table);
  });

  return applyFieldOverrides({
    data: dataFrames,
    fieldConfig: {
      defaults: {},
      overrides: [],
    },
    replaceVariables: (value: any) => value,
    theme: config.theme,
  });
}

function buildDataQueryModel(queryOptions: QueryGroupOptions, defaultDataSource: DataSourceApi) {
  return queryOptions.queries.map((query) => {
    let dataSource: QueryGroupDataSource;
    const isExpression = query.datasource === ExpressionDatasourceID;

    if (isExpression) {
      dataSource = { name: ExpressionDatasourceID, uid: ExpressionDatasourceID };
    } else {
      const dataSourceSetting = getDataSourceSrv().getInstanceSettings(query.datasource);

      dataSource = {
        name: dataSourceSetting?.name ?? defaultDataSource.name,
        uid: dataSourceSetting?.uid ?? defaultDataSource.uid,
      };
    }

    return {
      model: {
        ...query,
        type: isExpression ? (query as ExpressionQuery).type : query.queryType,
        datasource: dataSource.name,
        datasourceUid: dataSource.uid,
      },
      refId: query.refId,
      relativeTimeRange: {
        From: 500,
        To: 0,
      },
    };
  });
}