grafana/public/app/features/explore/ExplorePage.tsx

import { css } from '@emotion/css';
import { inRange } from 'lodash';
import React, { useEffect, useState } from 'react';
import { useWindowSize } from 'react-use';

import { ErrorBoundaryAlert } from '@grafana/ui';
import { SplitPaneWrapper } from 'app/core/components/SplitPaneWrapper/SplitPaneWrapper';
import { useGrafana } from 'app/core/context/GrafanaContext';
import { useNavModel } from 'app/core/hooks/useNavModel';
import { GrafanaRouteComponentProps } from 'app/core/navigation/types';
import { useDispatch, useSelector } from 'app/types';
import { ExploreId, ExploreQueryParams } from 'app/types/explore';

import { ExploreActions } from './ExploreActions';
import { ExplorePaneContainer } from './ExplorePaneContainer';
import { useExploreCorrelations } from './hooks/useExploreCorrelations';
import { useExplorePageTitle } from './hooks/useExplorePageTitle';
import { useStateSync } from './hooks/useStateSync';
import { useStopQueries } from './hooks/useStopQueries';
import { useTimeSrvFix } from './hooks/useTimeSrvFix';
import { splitSizeUpdateAction } from './state/main';
import { selectOrderedExplorePanes } from './state/selectors';

const styles = {
  pageScrollbarWrapper: css`
    width: 100%;
    flex-grow: 1;
    min-height: 0;
    height: 100%;
    position: relative;
  `,
};

export default function ExplorePage(props: GrafanaRouteComponentProps<{}, ExploreQueryParams>) {
  useStopQueries();
  useTimeSrvFix();
  useStateSync(props.queryParams);
  useExplorePageTitle();
  useExploreCorrelations();
  const dispatch = useDispatch();
  const { keybindings, chrome } = useGrafana();
  const navModel = useNavModel('explore');
  const [rightPaneWidthRatio, setRightPaneWidthRatio] = useState(0.5);
  const { width: windowWidth } = useWindowSize();
  const minWidth = 200;
  const exploreState = useSelector((state) => state.explore);

  const panes = useSelector(selectOrderedExplorePanes);

  useEffect(() => {
    //This is needed for breadcrumbs and topnav.
    //We should probably abstract this out at some point
    chrome.update({ sectionNav: navModel });
  }, [chrome, navModel]);

  useEffect(() => {
    keybindings.setupTimeRangeBindings(false);
  }, [keybindings]);

  const updateSplitSize = (size: number) => {
    const evenSplitWidth = windowWidth / 2;
    const areBothSimilar = inRange(size, evenSplitWidth - 100, evenSplitWidth + 100);
    if (areBothSimilar) {
      dispatch(splitSizeUpdateAction({ largerExploreId: undefined }));
    } else {
      dispatch(
        splitSizeUpdateAction({
          largerExploreId: size > evenSplitWidth ? ExploreId.right : ExploreId.left,
        })
      );
    }

    setRightPaneWidthRatio(size / windowWidth);
  };

  const hasSplit = Object.entries(panes).length > 1;
  let widthCalc = 0;
  if (hasSplit) {
    if (!exploreState.evenSplitPanes && exploreState.maxedExploreId) {
      widthCalc = exploreState.maxedExploreId === ExploreId.right ? windowWidth - minWidth : minWidth;
    } else if (exploreState.evenSplitPanes) {
      widthCalc = Math.floor(windowWidth / 2);
    } else if (rightPaneWidthRatio !== undefined) {
      widthCalc = windowWidth * rightPaneWidthRatio;
    }
  }

  return (
    <div className={styles.pageScrollbarWrapper}>
      <ExploreActions exploreIdLeft={ExploreId.left} exploreIdRight={ExploreId.right} />

      <SplitPaneWrapper
        splitOrientation="vertical"
        paneSize={widthCalc}
        minSize={minWidth}
        maxSize={minWidth * -1}
        primary="second"
        splitVisible={hasSplit}
        paneStyle={{ overflow: 'auto', display: 'flex', flexDirection: 'column' }}
        onDragFinished={(size) => {
          if (size) {
            updateSplitSize(size);
          }
        }}
      >
        {Object.keys(panes).map((exploreId) => {
          return (
            <ErrorBoundaryAlert key={exploreId} style="page">
              <ExplorePaneContainer exploreId={exploreId as ExploreId} />
            </ErrorBoundaryAlert>
          );
        })}
      </SplitPaneWrapper>
    </div>
  );
}