Add type annotation for RelativeTimestamp component (#24749)

app/javascript/mastodon/components/relative_timestamp.tsx

@@ -0,0 +1,203 @@
+import React from 'react';
+import { injectIntl, defineMessages, InjectedIntl } from 'react-intl';
+
+const messages = defineMessages({
+  today: { id: 'relative_time.today', defaultMessage: 'today' },
+  just_now: { id: 'relative_time.just_now', defaultMessage: 'now' },
+  just_now_full: { id: 'relative_time.full.just_now', defaultMessage: 'just now' },
+  seconds: { id: 'relative_time.seconds', defaultMessage: '{number}s' },
+  seconds_full: { id: 'relative_time.full.seconds', defaultMessage: '{number, plural, one {# second} other {# seconds}} ago' },
+  minutes: { id: 'relative_time.minutes', defaultMessage: '{number}m' },
+  minutes_full: { id: 'relative_time.full.minutes', defaultMessage: '{number, plural, one {# minute} other {# minutes}} ago' },
+  hours: { id: 'relative_time.hours', defaultMessage: '{number}h' },
+  hours_full: { id: 'relative_time.full.hours', defaultMessage: '{number, plural, one {# hour} other {# hours}} ago' },
+  days: { id: 'relative_time.days', defaultMessage: '{number}d' },
+  days_full: { id: 'relative_time.full.days', defaultMessage: '{number, plural, one {# day} other {# days}} ago' },
+  moments_remaining: { id: 'time_remaining.moments', defaultMessage: 'Moments remaining' },
+  seconds_remaining: { id: 'time_remaining.seconds', defaultMessage: '{number, plural, one {# second} other {# seconds}} left' },
+  minutes_remaining: { id: 'time_remaining.minutes', defaultMessage: '{number, plural, one {# minute} other {# minutes}} left' },
+  hours_remaining: { id: 'time_remaining.hours', defaultMessage: '{number, plural, one {# hour} other {# hours}} left' },
+  days_remaining: { id: 'time_remaining.days', defaultMessage: '{number, plural, one {# day} other {# days}} left' },
+});
+
+const dateFormatOptions = {
+  hour12: false,
+  year: 'numeric',
+  month: 'short',
+  day: '2-digit',
+  hour: '2-digit',
+  minute: '2-digit',
+} as const;
+
+const shortDateFormatOptions = {
+  month: 'short',
+  day: 'numeric',
+} as const;
+
+const SECOND = 1000;
+const MINUTE = 1000 * 60;
+const HOUR   = 1000 * 60 * 60;
+const DAY    = 1000 * 60 * 60 * 24;
+
+const MAX_DELAY = 2147483647;
+
+const selectUnits = (delta: number) => {
+  const absDelta = Math.abs(delta);
+
+  if (absDelta < MINUTE) {
+    return 'second';
+  } else if (absDelta < HOUR) {
+    return 'minute';
+  } else if (absDelta < DAY) {
+    return 'hour';
+  }
+
+  return 'day';
+};
+
+const getUnitDelay = (units: string) => {
+  switch (units) {
+  case 'second':
+    return SECOND;
+  case 'minute':
+    return MINUTE;
+  case 'hour':
+    return HOUR;
+  case 'day':
+    return DAY;
+  default:
+    return MAX_DELAY;
+  }
+};
+
+export const timeAgoString = (intl: InjectedIntl, date: Date, now: number, year: number, timeGiven: boolean, short?: boolean) => {
+  const delta = now - date.getTime();
+
+  let relativeTime;
+
+  if (delta < DAY && !timeGiven) {
+    relativeTime = intl.formatMessage(messages.today);
+  } else if (delta < 10 * SECOND) {
+    relativeTime = intl.formatMessage(short ? messages.just_now : messages.just_now_full);
+  } else if (delta < 7 * DAY) {
+    if (delta < MINUTE) {
+      relativeTime = intl.formatMessage(short ? messages.seconds : messages.seconds_full, { number: Math.floor(delta / SECOND) });
+    } else if (delta < HOUR) {
+      relativeTime = intl.formatMessage(short ? messages.minutes : messages.minutes_full, { number: Math.floor(delta / MINUTE) });
+    } else if (delta < DAY) {
+      relativeTime = intl.formatMessage(short ? messages.hours : messages.hours_full, { number: Math.floor(delta / HOUR) });
+    } else {
+      relativeTime = intl.formatMessage(short ? messages.days : messages.days_full, { number: Math.floor(delta / DAY) });
+    }
+  } else if (date.getFullYear() === year) {
+    relativeTime = intl.formatDate(date, shortDateFormatOptions);
+  } else {
+    relativeTime = intl.formatDate(date, { ...shortDateFormatOptions, year: 'numeric' });
+  }
+
+  return relativeTime;
+};
+
+const timeRemainingString = (intl: InjectedIntl, date: Date, now: number, timeGiven = true) => {
+  const delta = date.getTime() - now;
+
+  let relativeTime;
+
+  if (delta < DAY && !timeGiven) {
+    relativeTime = intl.formatMessage(messages.today);
+  } else if (delta < 10 * SECOND) {
+    relativeTime = intl.formatMessage(messages.moments_remaining);
+  } else if (delta < MINUTE) {
+    relativeTime = intl.formatMessage(messages.seconds_remaining, { number: Math.floor(delta / SECOND) });
+  } else if (delta < HOUR) {
+    relativeTime = intl.formatMessage(messages.minutes_remaining, { number: Math.floor(delta / MINUTE) });
+  } else if (delta < DAY) {
+    relativeTime = intl.formatMessage(messages.hours_remaining, { number: Math.floor(delta / HOUR) });
+  } else {
+    relativeTime = intl.formatMessage(messages.days_remaining, { number: Math.floor(delta / DAY) });
+  }
+
+  return relativeTime;
+};
+
+type Props = {
+  intl: InjectedIntl;
+  timestamp: string;
+  year: number;
+  futureDate?: boolean;
+  short?: boolean;
+}
+type States = {
+  now: number;
+}
+class RelativeTimestamp extends React.Component<Props, States> {
+
+  state = {
+    now: this.props.intl.now(),
+  };
+
+  static defaultProps = {
+    year: (new Date()).getFullYear(),
+    short: true,
+  };
+
+  _timer: number | undefined;
+
+  shouldComponentUpdate (nextProps: Props, nextState: States) {
+    // As of right now the locale doesn't change without a new page load,
+    // but we might as well check in case that ever changes.
+    return this.props.timestamp !== nextProps.timestamp ||
+      this.props.intl.locale !== nextProps.intl.locale ||
+      this.state.now !== nextState.now;
+  }
+
+  UNSAFE_componentWillReceiveProps (nextProps: Props) {
+    if (this.props.timestamp !== nextProps.timestamp) {
+      this.setState({ now: this.props.intl.now() });
+    }
+  }
+
+  componentDidMount () {
+    this._scheduleNextUpdate(this.props, this.state);
+  }
+
+  UNSAFE_componentWillUpdate (nextProps: Props, nextState: States) {
+    this._scheduleNextUpdate(nextProps, nextState);
+  }
+
+  componentWillUnmount () {
+    window.clearTimeout(this._timer);
+  }
+
+  _scheduleNextUpdate (props: Props, state: States) {
+    window.clearTimeout(this._timer);
+
+    const { timestamp }  = props;
+    const delta          = (new Date(timestamp)).getTime() - state.now;
+    const unitDelay      = getUnitDelay(selectUnits(delta));
+    const unitRemainder  = Math.abs(delta % unitDelay);
+    const updateInterval = 1000 * 10;
+    const delay          = delta < 0 ? Math.max(updateInterval, unitDelay - unitRemainder) : Math.max(updateInterval, unitRemainder);
+
+    this._timer = window.setTimeout(() => {
+      this.setState({ now: this.props.intl.now() });
+    }, delay);
+  }
+
+  render () {
+    const { timestamp, intl, year, futureDate, short } = this.props;
+
+    const timeGiven    = timestamp.includes('T');
+    const date         = new Date(timestamp);
+    const relativeTime = futureDate ? timeRemainingString(intl, date, this.state.now, timeGiven) : timeAgoString(intl, date, this.state.now, year, timeGiven, short);
+
+    return (
+      <time dateTime={timestamp} title={intl.formatDate(date, dateFormatOptions)}>
+        {relativeTime}
+      </time>
+    );
+  }
+
+}
+
+export default injectIntl(RelativeTimestamp);