import {Fragment, useCallback} from 'react';
import styled from '@emotion/styled';

import {
  Panel as BasePanel,
  PanelBody as BasePanelBody,
  PanelHeader as BasePanelHeader,
} from 'sentry/components/panels';
import Placeholder from 'sentry/components/placeholder';
import {useReplayContext} from 'sentry/components/replays/replayContext';
import {relativeTimeInMs} from 'sentry/components/replays/utils';
import {t} from 'sentry/locale';
import space from 'sentry/styles/space';
import {Crumb} from 'sentry/types/breadcrumbs';
import {EventTransaction} from 'sentry/types/event';
import {getPrevBreadcrumb} from 'sentry/utils/replays/getBreadcrumb';

import BreadcrumbItem from './breadcrumbItem';

function CrumbPlaceholder({number}: {number: number}) {
  return (
    <Fragment>
      {[...Array(number)].map((_, i) => (
        <PlaceholderMargin key={i} height="40px" />
      ))}
    </Fragment>
  );
}

type Props = {
  /**
   * Raw breadcrumbs, `undefined` means it is still loading
   */
  crumbs: Crumb[] | undefined;
  /**
   * Root replay event, `undefined` means it is still loading
   */
  event: EventTransaction | undefined;
};

function Breadcrumbs({event, crumbs: allCrumbs}: Props) {
  const {
    setCurrentTime,
    setCurrentHoverTime,
    currentHoverTime,
    currentTime,
    highlight,
    removeHighlight,
    clearAllHighlights,
  } = useReplayContext();

  const startTimestamp = event?.startTimestamp || 0;

  const isLoaded = Boolean(event);

  const crumbs =
    allCrumbs?.filter(crumb => !['console'].includes(crumb.category || '')) || [];

  const currentUserAction = getPrevBreadcrumb({
    crumbs,
    targetTimestampMs: startTimestamp * 1000 + currentTime,
    allowExact: true,
  });

  const closestUserAction =
    currentHoverTime !== undefined
      ? getPrevBreadcrumb({
          crumbs,
          targetTimestampMs: startTimestamp * 1000 + (currentHoverTime ?? 0),
          allowExact: true,
        })
      : undefined;

  const handleMouseEnter = useCallback(
    (item: Crumb) => {
      if (startTimestamp) {
        setCurrentHoverTime(relativeTimeInMs(item.timestamp ?? '', startTimestamp));
      }

      if (item.data && 'nodeId' in item.data) {
        // XXX: Kind of hacky, but mouseLeave does not fire if you move from a
        // crumb to a tooltip
        clearAllHighlights();
        highlight({nodeId: item.data.nodeId});
      }
    },
    [setCurrentHoverTime, startTimestamp, highlight, clearAllHighlights]
  );

  const handleMouseLeave = useCallback(
    (item: Crumb) => {
      setCurrentHoverTime(undefined);

      if (item.data && 'nodeId' in item.data) {
        removeHighlight({nodeId: item.data.nodeId});
      }
    },
    [setCurrentHoverTime, removeHighlight]
  );

  const handleClick = useCallback(
    (crumb: Crumb) => {
      crumb.timestamp !== undefined
        ? setCurrentTime(relativeTimeInMs(crumb.timestamp, startTimestamp))
        : null;
    },
    [setCurrentTime, startTimestamp]
  );

  return (
    <Panel>
      <PanelHeader>{t('Breadcrumbs')}</PanelHeader>

      <PanelBody>
        {!isLoaded && <CrumbPlaceholder number={4} />}
        {isLoaded &&
          crumbs.map(crumb => (
            <BreadcrumbItem
              key={crumb.id}
              crumb={crumb}
              startTimestamp={startTimestamp}
              isHovered={closestUserAction?.id === crumb.id}
              isSelected={currentUserAction?.id === crumb.id}
              onMouseEnter={handleMouseEnter}
              onMouseLeave={handleMouseLeave}
              onClick={handleClick}
            />
          ))}
      </PanelBody>
    </Panel>
  );
}

// FYI: Since the Replay Player has dynamic height based
// on the width of the window,
// height: 0; will helps us to reset the height
// min-height: 100%; will helps us to grow at the same height of Player
const Panel = styled(BasePanel)`
  width: 100%;
  display: grid;
  grid-template-rows: auto 1fr;
  height: 0;
  min-height: 100%;
  @media only screen and (max-width: ${p => p.theme.breakpoints.large}) {
    height: fit-content;
    max-height: 400px;
    margin-top: ${space(2)};
  }
`;

const PanelHeader = styled(BasePanelHeader)`
  background-color: ${p => p.theme.background};
  border-bottom: none;
  font-size: ${p => p.theme.fontSizeSmall};
  color: ${p => p.theme.gray300};
  text-transform: capitalize;
  padding: ${space(1.5)} ${space(2)} ${space(0.5)};
`;

const PanelBody = styled(BasePanelBody)`
  overflow-y: auto;
`;

const PlaceholderMargin = styled(Placeholder)`
  margin: ${space(1)} ${space(1.5)};
  width: auto;
`;

export default Breadcrumbs;