Fix #3665 - Refactor timelines reducer (#3686)

* Move ancestors/descendants out of timelines reducer

* Refactor timelines reducer

All types of timelines now have a flat structure and use the same
reducer functions and actions

* Reintroduce some missing behaviours

* Fix wrong import in reports

* Fix includes typo

* Fix issue related to "next" pagination in timelines and notifications

* Fix bug with timeline's initial state, expandNotifications

21 files changed, 217 insertions, 594 deletions

diff --git a/app/javascript/mastodon/actions/accounts.js b/app/javascript/mastodon/actions/accounts.js
index 405032460..a862798f9 100644
--- a/app/javascript/mastodon/actions/accounts.js
+++ b/app/javascript/mastodon/actions/accounts.js
@@ -29,22 +29,6 @@ export const ACCOUNT_UNMUTE_REQUEST = 'ACCOUNT_UNMUTE_REQUEST';
 export const ACCOUNT_UNMUTE_SUCCESS = 'ACCOUNT_UNMUTE_SUCCESS';
 export const ACCOUNT_UNMUTE_FAIL    = 'ACCOUNT_UNMUTE_FAIL';
 
-export const ACCOUNT_TIMELINE_FETCH_REQUEST = 'ACCOUNT_TIMELINE_FETCH_REQUEST';
-export const ACCOUNT_TIMELINE_FETCH_SUCCESS = 'ACCOUNT_TIMELINE_FETCH_SUCCESS';
-export const ACCOUNT_TIMELINE_FETCH_FAIL    = 'ACCOUNT_TIMELINE_FETCH_FAIL';
-
-export const ACCOUNT_TIMELINE_EXPAND_REQUEST = 'ACCOUNT_TIMELINE_EXPAND_REQUEST';
-export const ACCOUNT_TIMELINE_EXPAND_SUCCESS = 'ACCOUNT_TIMELINE_EXPAND_SUCCESS';
-export const ACCOUNT_TIMELINE_EXPAND_FAIL    = 'ACCOUNT_TIMELINE_EXPAND_FAIL';
-
-export const ACCOUNT_MEDIA_TIMELINE_FETCH_REQUEST = 'ACCOUNT_MEDIA_TIMELINE_FETCH_REQUEST';
-export const ACCOUNT_MEDIA_TIMELINE_FETCH_SUCCESS = 'ACCOUNT_MEDIA_TIMELINE_FETCH_SUCCESS';
-export const ACCOUNT_MEDIA_TIMELINE_FETCH_FAIL    = 'ACCOUNT_MEDIA_TIMELINE_FETCH_FAIL';
-
-export const ACCOUNT_MEDIA_TIMELINE_EXPAND_REQUEST = 'ACCOUNT_MEDIA_TIMELINE_EXPAND_REQUEST';
-export const ACCOUNT_MEDIA_TIMELINE_EXPAND_SUCCESS = 'ACCOUNT_MEDIA_TIMELINE_EXPAND_SUCCESS';
-export const ACCOUNT_MEDIA_TIMELINE_EXPAND_FAIL    = 'ACCOUNT_MEDIA_TIMELINE_EXPAND_FAIL';
-
 export const FOLLOWERS_FETCH_REQUEST = 'FOLLOWERS_FETCH_REQUEST';
 export const FOLLOWERS_FETCH_SUCCESS = 'FOLLOWERS_FETCH_SUCCESS';
 export const FOLLOWERS_FETCH_FAIL    = 'FOLLOWERS_FETCH_FAIL';
@@ -99,99 +83,6 @@ export function fetchAccount(id) {
   };
 };
 
-export function fetchAccountTimeline(id, replace = false) {
-  return (dispatch, getState) => {
-    const ids      = getState().getIn(['timelines', 'accounts_timelines', id, 'items'], Immutable.List());
-    const newestId = ids.size > 0 ? ids.first() : null;
-
-    let params = {};
-    let skipLoading = false;
-
-    replace = replace || newestId === null;
-
-    if (!replace) {
-      params.since_id = newestId;
-      skipLoading = true;
-    }
-
-    dispatch(fetchAccountTimelineRequest(id, skipLoading));
-
-    api(getState).get(`/api/v1/accounts/${id}/statuses`, { params }).then(response => {
-      const next = getLinks(response).refs.find(link => link.rel === 'next');
-      dispatch(fetchAccountTimelineSuccess(id, response.data, replace, skipLoading, next));
-    }).catch(error => {
-      dispatch(fetchAccountTimelineFail(id, error, skipLoading));
-    });
-  };
-};
-
-export function fetchAccountMediaTimeline(id, replace = false) {
-  return (dispatch, getState) => {
-    const ids      = getState().getIn(['timelines', 'accounts_media_timelines', id, 'items'], Immutable.List());
-    const newestId = ids.size > 0 ? ids.first() : null;
-
-    let params = { only_media: 'true', limit: 12 };
-    let skipLoading = false;
-
-    replace = replace || newestId === null;
-
-    if (!replace) {
-      params.since_id = newestId;
-      skipLoading = true;
-    }
-
-    dispatch(fetchAccountMediaTimelineRequest(id, skipLoading));
-
-    api(getState).get(`/api/v1/accounts/${id}/statuses`, { params }).then(response => {
-      const next = getLinks(response).refs.find(link => link.rel === 'next');
-      dispatch(fetchAccountMediaTimelineSuccess(id, response.data, replace, skipLoading, next));
-    }).catch(error => {
-      dispatch(fetchAccountMediaTimelineFail(id, error, skipLoading));
-    });
-  };
-};
-
-export function expandAccountTimeline(id) {
-  return (dispatch, getState) => {
-    const lastId = getState().getIn(['timelines', 'accounts_timelines', id, 'items'], Immutable.List()).last();
-
-    dispatch(expandAccountTimelineRequest(id));
-
-    api(getState).get(`/api/v1/accounts/${id}/statuses`, {
-      params: {
-        limit: 10,
-        max_id: lastId,
-      },
-    }).then(response => {
-      const next = getLinks(response).refs.find(link => link.rel === 'next');
-      dispatch(expandAccountTimelineSuccess(id, response.data, next));
-    }).catch(error => {
-      dispatch(expandAccountTimelineFail(id, error));
-    });
-  };
-};
-
-export function expandAccountMediaTimeline(id) {
-  return (dispatch, getState) => {
-    const lastId = getState().getIn(['timelines', 'accounts_media_timelines', id, 'items'], Immutable.List()).last();
-
-    dispatch(expandAccountMediaTimelineRequest(id));
-
-    api(getState).get(`/api/v1/accounts/${id}/statuses`, {
-      params: {
-        limit: 12,
-        only_media: 'true',
-        max_id: lastId,
-      },
-    }).then(response => {
-      const next = getLinks(response).refs.find(link => link.rel === 'next');
-      dispatch(expandAccountMediaTimelineSuccess(id, response.data, next));
-    }).catch(error => {
-      dispatch(expandAccountMediaTimelineFail(id, error));
-    });
-  };
-};
-
 export function fetchAccountRequest(id) {
   return {
     type: ACCOUNT_FETCH_REQUEST,
@@ -281,112 +172,6 @@ export function unfollowAccountFail(error) {
   };
 };
 
-export function fetchAccountTimelineRequest(id, skipLoading) {
-  return {
-    type: ACCOUNT_TIMELINE_FETCH_REQUEST,
-    id,
-    skipLoading,
-  };
-};
-
-export function fetchAccountTimelineSuccess(id, statuses, replace, skipLoading, next) {
-  return {
-    type: ACCOUNT_TIMELINE_FETCH_SUCCESS,
-    id,
-    statuses,
-    replace,
-    skipLoading,
-    next,
-  };
-};
-
-export function fetchAccountTimelineFail(id, error, skipLoading) {
-  return {
-    type: ACCOUNT_TIMELINE_FETCH_FAIL,
-    id,
-    error,
-    skipLoading,
-    skipAlert: error.response.status === 404,
-  };
-};
-
-export function fetchAccountMediaTimelineRequest(id, skipLoading) {
-  return {
-    type: ACCOUNT_MEDIA_TIMELINE_FETCH_REQUEST,
-    id,
-    skipLoading,
-  };
-};
-
-export function fetchAccountMediaTimelineSuccess(id, statuses, replace, skipLoading, next) {
-  return {
-    type: ACCOUNT_MEDIA_TIMELINE_FETCH_SUCCESS,
-    id,
-    statuses,
-    replace,
-    skipLoading,
-    next,
-  };
-};
-
-export function fetchAccountMediaTimelineFail(id, error, skipLoading) {
-  return {
-    type: ACCOUNT_MEDIA_TIMELINE_FETCH_FAIL,
-    id,
-    error,
-    skipLoading,
-    skipAlert: error.response.status === 404,
-  };
-};
-
-export function expandAccountTimelineRequest(id) {
-  return {
-    type: ACCOUNT_TIMELINE_EXPAND_REQUEST,
-    id,
-  };
-};
-
-export function expandAccountTimelineSuccess(id, statuses, next) {
-  return {
-    type: ACCOUNT_TIMELINE_EXPAND_SUCCESS,
-    id,
-    statuses,
-    next,
-  };
-};
-
-export function expandAccountTimelineFail(id, error) {
-  return {
-    type: ACCOUNT_TIMELINE_EXPAND_FAIL,
-    id,
-    error,
-  };
-};
-
-export function expandAccountMediaTimelineRequest(id) {
-  return {
-    type: ACCOUNT_MEDIA_TIMELINE_EXPAND_REQUEST,
-    id,
-  };
-};
-
-export function expandAccountMediaTimelineSuccess(id, statuses, next) {
-  return {
-    type: ACCOUNT_MEDIA_TIMELINE_EXPAND_SUCCESS,
-    id,
-    statuses,
-    next,
-  };
-};
-
-export function expandAccountMediaTimelineFail(id, error) {
-  return {
-    type: ACCOUNT_MEDIA_TIMELINE_EXPAND_FAIL,
-    id,
-    error,
-  };
-};
-
 export function blockAccount(id) {
   return (dispatch, getState) => {
     dispatch(blockAccountRequest(id));
diff --git a/app/javascript/mastodon/actions/notifications.js b/app/javascript/mastodon/actions/notifications.js
index 51b06ed32..d3de2d871 100644
--- a/app/javascript/mastodon/actions/notifications.js
+++ b/app/javascript/mastodon/actions/notifications.js
@@ -124,25 +124,22 @@ export function refreshNotificationsFail(error, skipLoading) {
 
 export function expandNotifications() {
   return (dispatch, getState) => {
-    const url    = getState().getIn(['notifications', 'next'], null);
-    const lastId = getState().getIn(['notifications', 'items']).last();
+    const items  = getState().getIn(['notifications', 'items'], Immutable.List());
 
-    if (url === null || getState().getIn(['notifications', 'isLoading'])) {
+    if (getState().getIn(['notifications', 'isLoading']) || items.size === 0) {
       return;
     }
 
-    dispatch(expandNotificationsRequest());
-
     const params = {
-      max_id: lastId,
+      max_id: items.last().get('id'),
       limit: 20,
+      exclude_types: excludeTypesFromSettings(getState()),
     };
 
-    params.exclude_types = excludeTypesFromSettings(getState());
+    dispatch(expandNotificationsRequest());
 
-    api(getState).get(url, params).then(response => {
+    api(getState).get('/api/v1/notifications', { params }).then(response => {
       const next = getLinks(response).refs.find(link => link.rel === 'next');
-
       dispatch(expandNotificationsSuccess(response.data, next ? next.uri : null));
       fetchRelatedRelationships(dispatch, response.data);
     }).catch(error => {
diff --git a/app/javascript/mastodon/actions/timelines.js b/app/javascript/mastodon/actions/timelines.js
index 98e441cd1..cb4410eba 100644
--- a/app/javascript/mastodon/actions/timelines.js
+++ b/app/javascript/mastodon/actions/timelines.js
@@ -56,91 +56,89 @@ export function deleteFromTimelines(id) {
   };
 };
 
-export function refreshTimelineRequest(timeline, id, skipLoading) {
+export function refreshTimelineRequest(timeline, skipLoading) {
   return {
     type: TIMELINE_REFRESH_REQUEST,
     timeline,
-    id,
     skipLoading,
   };
 };
 
-export function refreshTimeline(timeline, id = null) {
+export function refreshTimeline(timelineId, path, params = {}) {
   return function (dispatch, getState) {
-    if (getState().getIn(['timelines', timeline, 'isLoading'])) {
+    const timeline = getState().getIn(['timelines', timelineId], Immutable.Map());
+
+    if (timeline.get('isLoading') || timeline.get('online')) {
       return;
     }
 
-    const ids      = getState().getIn(['timelines', timeline, 'items'], Immutable.List());
+    const ids      = timeline.get('items', Immutable.List());
     const newestId = ids.size > 0 ? ids.first() : null;
-    let params     = getState().getIn(['timelines', timeline, 'params'], {});
-    const path     = getState().getIn(['timelines', timeline, 'path'])(id);
-
-    let skipLoading = false;
 
-    if (newestId !== null && getState().getIn(['timelines', timeline, 'loaded']) && (id === null || getState().getIn(['timelines', timeline, 'id']) === id)) {
-      if (id === null && getState().getIn(['timelines', timeline, 'online'])) {
-        // Skip refreshing when timeline is live anyway
-        return;
-      }
+    let skipLoading = timeline.get('loaded');
 
-      params          = { ...params, since_id: newestId };
-      skipLoading     = true;
-    } else if (getState().getIn(['timelines', timeline, 'loaded'])) {
-      skipLoading = true;
+    if (newestId !== null) {
+      params.since_id = newestId;
     }
 
-    dispatch(refreshTimelineRequest(timeline, id, skipLoading));
+    dispatch(refreshTimelineRequest(timelineId, skipLoading));
 
     api(getState).get(path, { params }).then(response => {
       const next = getLinks(response).refs.find(link => link.rel === 'next');
-      dispatch(refreshTimelineSuccess(timeline, response.data, skipLoading, next ? next.uri : null));
+      dispatch(refreshTimelineSuccess(timelineId, response.data, skipLoading, next ? next.uri : null));
     }).catch(error => {
-      dispatch(refreshTimelineFail(timeline, error, skipLoading));
+      dispatch(refreshTimelineFail(timelineId, error, skipLoading));
     });
   };
 };
 
+export const refreshHomeTimeline         = () => refreshTimeline('home', '/api/v1/timelines/home');
+export const refreshPublicTimeline       = () => refreshTimeline('public', '/api/v1/timelines/public');
+export const refreshCommunityTimeline    = () => refreshTimeline('community', '/api/v1/timelines/public', { local: true });
+export const refreshAccountTimeline      = accountId => refreshTimeline(`account:${accountId}`, `/api/v1/accounts/${accountId}/statuses`);
+export const refreshAccountMediaTimeline = accountId => refreshTimeline(`account:${accountId}:media`, `/api/v1/accounts/${accountId}/statuses`, { only_media: true });
+export const refreshHashtagTimeline      = hashtag => refreshTimeline(`hashtag:${hashtag}`, `/api/v1/timelines/tag/${hashtag}`);
+
 export function refreshTimelineFail(timeline, error, skipLoading) {
   return {
     type: TIMELINE_REFRESH_FAIL,
     timeline,
     error,
     skipLoading,
+    skipAlert: error.response.status === 404,
   };
 };
 
-export function expandTimeline(timeline) {
+export function expandTimeline(timelineId, path, params = {}) {
   return (dispatch, getState) => {
-    if (getState().getIn(['timelines', timeline, 'isLoading'])) {
-      return;
-    }
+    const timeline = getState().getIn(['timelines', timelineId], Immutable.Map());
+    const ids      = timeline.get('items', Immutable.List());
 
-    if (getState().getIn(['timelines', timeline, 'items']).size === 0) {
+    if (timeline.get('isLoading') || ids.size === 0) {
       return;
     }
 
-    const path   = getState().getIn(['timelines', timeline, 'path'])(getState().getIn(['timelines', timeline, 'id']));
-    const params = getState().getIn(['timelines', timeline, 'params'], {});
-    const lastId = getState().getIn(['timelines', timeline, 'items']).last();
+    params.max_id = ids.last();
+    params.limit  = 10;
 
-    dispatch(expandTimelineRequest(timeline));
+    dispatch(expandTimelineRequest(timelineId));
 
-    api(getState).get(path, {
-      params: {
-        ...params,
-        max_id: lastId,
-        limit: 10,
-      },
-    }).then(response => {
+    api(getState).get(path, { params }).then(response => {
       const next = getLinks(response).refs.find(link => link.rel === 'next');
-      dispatch(expandTimelineSuccess(timeline, response.data, next ? next.uri : null));
+      dispatch(expandTimelineSuccess(timelineId, response.data, next ? next.uri : null));
     }).catch(error => {
-      dispatch(expandTimelineFail(timeline, error));
+      dispatch(expandTimelineFail(timelineId, error));
     });
   };
 };
 
+export const expandHomeTimeline         = () => expandTimeline('home', '/api/v1/timelines/home');
+export const expandPublicTimeline       = () => expandTimeline('public', '/api/v1/timelines/public');
+export const expandCommunityTimeline    = () => expandTimeline('community', '/api/v1/timelines/public', { local: true });
+export const expandAccountTimeline      = accountId => expandTimeline(`account:${accountId}`, `/api/v1/accounts/${accountId}/statuses`);
+export const expandAccountMediaTimeline = accountId => expandTimeline(`account:${accountId}:media`, `/api/v1/accounts/${accountId}/statuses`, { only_media: true });
+export const expandHashtagTimeline      = hashtag => expandTimeline(`hashtag:${hashtag}`, `/api/v1/timelines/tag/${hashtag}`);
+
 export function expandTimelineRequest(timeline) {
   return {
     type: TIMELINE_EXPAND_REQUEST,
diff --git a/app/javascript/mastodon/containers/mastodon.js b/app/javascript/mastodon/containers/mastodon.js
index 6d1c3f983..5e009cfa3 100644
--- a/app/javascript/mastodon/containers/mastodon.js
+++ b/app/javascript/mastodon/containers/mastodon.js
@@ -6,7 +6,7 @@ import {
   refreshTimelineSuccess,
   updateTimeline,
   deleteFromTimelines,
-  refreshTimeline,
+  refreshHomeTimeline,
   connectTimeline,
   disconnectTimeline,
 } from '../actions/timelines';
@@ -65,7 +65,7 @@ class Mastodon extends React.PureComponent {
 
     const setupPolling = () => {
       this.polling = setInterval(() => {
-        store.dispatch(refreshTimeline('home'));
+        store.dispatch(refreshHomeTimeline());
         store.dispatch(refreshNotifications());
       }, 20000);
     };
@@ -104,7 +104,7 @@ class Mastodon extends React.PureComponent {
       reconnected () {
         clearPolling();
         store.dispatch(connectTimeline('home'));
-        store.dispatch(refreshTimeline('home'));
+        store.dispatch(refreshHomeTimeline());
         store.dispatch(refreshNotifications());
       },
 
diff --git a/app/javascript/mastodon/features/account_gallery/index.js b/app/javascript/mastodon/features/account_gallery/index.js
index a15419ac7..fcbee3c89 100644
--- a/app/javascript/mastodon/features/account_gallery/index.js
+++ b/app/javascript/mastodon/features/account_gallery/index.js
@@ -2,11 +2,8 @@ import React from 'react';
 import { connect } from 'react-redux';
 import ImmutablePropTypes from 'react-immutable-proptypes';
 import PropTypes from 'prop-types';
-import {
-  fetchAccount,
-  fetchAccountMediaTimeline,
-  expandAccountMediaTimeline,
-} from '../../actions/accounts';
+import { fetchAccount } from '../../actions/accounts';
+import { refreshAccountMediaTimeline, expandAccountMediaTimeline } from '../../actions/timelines';
 import LoadingIndicator from '../../components/loading_indicator';
 import Column from '../ui/components/column';
 import ColumnBackButton from '../../components/column_back_button';
@@ -21,8 +18,8 @@ import LoadMore from '../../components/load_more';
 
 const mapStateToProps = (state, props) => ({
   medias: getAccountGallery(state, Number(props.params.accountId)),
-  isLoading: state.getIn(['timelines', 'accounts_media_timelines', Number(props.params.accountId), 'isLoading']),
-  hasMore: !!state.getIn(['timelines', 'accounts_media_timelines', Number(props.params.accountId), 'next']),
+  isLoading: state.getIn(['timelines', `account:${Number(props.params.accountId)}:media`, 'isLoading']),
+  hasMore: !!state.getIn(['timelines', `account:${Number(props.params.accountId)}:media`, 'next']),
   autoPlayGif: state.getIn(['meta', 'auto_play_gif']),
 });
 
@@ -39,13 +36,13 @@ class AccountGallery extends ImmutablePureComponent {
 
   componentDidMount () {
     this.props.dispatch(fetchAccount(Number(this.props.params.accountId)));
-    this.props.dispatch(fetchAccountMediaTimeline(Number(this.props.params.accountId)));
+    this.props.dispatch(refreshAccountMediaTimeline(Number(this.props.params.accountId)));
   }
 
   componentWillReceiveProps (nextProps) {
     if (nextProps.params.accountId !== this.props.params.accountId && nextProps.params.accountId) {
       this.props.dispatch(fetchAccount(Number(nextProps.params.accountId)));
-      this.props.dispatch(fetchAccountMediaTimeline(Number(this.props.params.accountId)));
+      this.props.dispatch(refreshAccountMediaTimeline(Number(this.props.params.accountId)));
     }
   }
 
diff --git a/app/javascript/mastodon/features/account_timeline/index.js b/app/javascript/mastodon/features/account_timeline/index.js
index 299f9ad5c..1aab8f130 100644
--- a/app/javascript/mastodon/features/account_timeline/index.js
+++ b/app/javascript/mastodon/features/account_timeline/index.js
@@ -2,11 +2,8 @@ import React from 'react';
 import { connect } from 'react-redux';
 import ImmutablePropTypes from 'react-immutable-proptypes';
 import PropTypes from 'prop-types';
-import {
-  fetchAccount,
-  fetchAccountTimeline,
-  expandAccountTimeline,
-} from '../../actions/accounts';
+import { fetchAccount } from '../../actions/accounts';
+import { refreshAccountTimeline, expandAccountTimeline } from '../../actions/timelines';
 import StatusList from '../../components/status_list';
 import LoadingIndicator from '../../components/loading_indicator';
 import Column from '../ui/components/column';
@@ -16,9 +13,9 @@ import Immutable from 'immutable';
 import ImmutablePureComponent from 'react-immutable-pure-component';
 
 const mapStateToProps = (state, props) => ({
-  statusIds: state.getIn(['timelines', 'accounts_timelines', Number(props.params.accountId), 'items'], Immutable.List()),
-  isLoading: state.getIn(['timelines', 'accounts_timelines', Number(props.params.accountId), 'isLoading']),
-  hasMore: !!state.getIn(['timelines', 'accounts_timelines', Number(props.params.accountId), 'next']),
+  statusIds: state.getIn(['timelines', `account:${Number(props.params.accountId)}`, 'items'], Immutable.List()),
+  isLoading: state.getIn(['timelines', `account:${Number(props.params.accountId)}`, 'isLoading']),
+  hasMore: !!state.getIn(['timelines', `account:${Number(props.params.accountId)}`, 'next']),
   me: state.getIn(['meta', 'me']),
 });
 
@@ -35,13 +32,13 @@ class AccountTimeline extends ImmutablePureComponent {
 
   componentWillMount () {
     this.props.dispatch(fetchAccount(Number(this.props.params.accountId)));
-    this.props.dispatch(fetchAccountTimeline(Number(this.props.params.accountId)));
+    this.props.dispatch(refreshAccountTimeline(Number(this.props.params.accountId)));
   }
 
   componentWillReceiveProps (nextProps) {
     if (nextProps.params.accountId !== this.props.params.accountId && nextProps.params.accountId) {
       this.props.dispatch(fetchAccount(Number(nextProps.params.accountId)));
-      this.props.dispatch(fetchAccountTimeline(Number(nextProps.params.accountId)));
+      this.props.dispatch(refreshAccountTimeline(Number(nextProps.params.accountId)));
     }
   }
 
diff --git a/app/javascript/mastodon/features/community_timeline/index.js b/app/javascript/mastodon/features/community_timeline/index.js
index 44ea4dddd..4fbe67038 100644
--- a/app/javascript/mastodon/features/community_timeline/index.js
+++ b/app/javascript/mastodon/features/community_timeline/index.js
@@ -5,7 +5,8 @@ import StatusListContainer from '../ui/containers/status_list_container';
 import Column from '../../components/column';
 import ColumnHeader from '../../components/column_header';
 import {
-  refreshTimeline,
+  refreshCommunityTimeline,
+  expandCommunityTimeline,
   updateTimeline,
   deleteFromTimelines,
   connectTimeline,
@@ -61,7 +62,7 @@ class CommunityTimeline extends React.PureComponent {
   componentDidMount () {
     const { dispatch, streamingAPIBaseURL, accessToken } = this.props;
 
-    dispatch(refreshTimeline('community'));
+    dispatch(refreshCommunityTimeline());
 
     if (typeof this._subscription !== 'undefined') {
       return;
@@ -106,6 +107,10 @@ class CommunityTimeline extends React.PureComponent {
     this.column = c;
   }
 
+  handleLoadMore = () => {
+    this.props.dispatch(expandCommunityTimeline());
+  }
+
   render () {
     const { intl, hasUnread, columnId, multiColumn } = this.props;
     const pinned = !!columnId;
@@ -126,10 +131,10 @@ class CommunityTimeline extends React.PureComponent {
         </ColumnHeader>
 
         <StatusListContainer
-          {...this.props}
           trackScroll={!pinned}
           scrollKey={`community_timeline-${columnId}`}
-          type='community'
+          timelineId='community'
+          loadMore={this.handleLoadMore}
           emptyMessage={<FormattedMessage id='empty_column.community' defaultMessage='The local timeline is empty. Write something publicly to get the ball rolling!' />}
         />
       </Column>
diff --git a/app/javascript/mastodon/features/hashtag_timeline/index.js b/app/javascript/mastodon/features/hashtag_timeline/index.js
index 05e6d1996..ba6dbe6e5 100644
--- a/app/javascript/mastodon/features/hashtag_timeline/index.js
+++ b/app/javascript/mastodon/features/hashtag_timeline/index.js
@@ -5,7 +5,8 @@ import StatusListContainer from '../ui/containers/status_list_container';
 import Column from '../../components/column';
 import ColumnHeader from '../../components/column_header';
 import {
-  refreshTimeline,
+  refreshHashtagTimeline,
+  expandHashtagTimeline,
   updateTimeline,
   deleteFromTimelines,
 } from '../../actions/timelines';
@@ -81,13 +82,13 @@ class HashtagTimeline extends React.PureComponent {
     const { dispatch } = this.props;
     const { id } = this.props.params;
 
-    dispatch(refreshTimeline('tag', id));
+    dispatch(refreshHashtagTimeline(id));
     this._subscribe(dispatch, id);
   }
 
   componentWillReceiveProps (nextProps) {
     if (nextProps.params.id !== this.props.params.id) {
-      this.props.dispatch(refreshTimeline('tag', nextProps.params.id));
+      this.props.dispatch(refreshHashtagTimeline(nextProps.params.id));
       this._unsubscribe();
       this._subscribe(this.props.dispatch, nextProps.params.id);
     }
@@ -101,6 +102,10 @@ class HashtagTimeline extends React.PureComponent {
     this.column = c;
   }
 
+  handleLoadMore = () => {
+    this.props.dispatch(expandHashtagTimeline(this.props.params.id));
+  }
+
   render () {
     const { hasUnread, columnId, multiColumn } = this.props;
     const { id } = this.props.params;
@@ -123,8 +128,8 @@ class HashtagTimeline extends React.PureComponent {
         <StatusListContainer
           trackScroll={!pinned}
           scrollKey={`hashtag_timeline-${columnId}`}
-          type='tag'
-          id={id}
+          timelineId={`hashtag:${id}`}
+          loadMore={this.handleLoadMore}
           emptyMessage={<FormattedMessage id='empty_column.hashtag' defaultMessage='There is nothing in this hashtag yet.' />}
         />
       </Column>
diff --git a/app/javascript/mastodon/features/home_timeline/index.js b/app/javascript/mastodon/features/home_timeline/index.js
index 7439bf3a1..6d3968751 100644
--- a/app/javascript/mastodon/features/home_timeline/index.js
+++ b/app/javascript/mastodon/features/home_timeline/index.js
@@ -1,5 +1,6 @@
 import React from 'react';
 import { connect } from 'react-redux';
+import { expandHomeTimeline } from '../../actions/timelines';
 import PropTypes from 'prop-types';
 import StatusListContainer from '../ui/containers/status_list_container';
 import Column from '../../components/column';
@@ -52,6 +53,10 @@ class HomeTimeline extends React.PureComponent {
     this.column = c;
   }
 
+  handleLoadMore = () => {
+    this.props.dispatch(expandHomeTimeline());
+  }
+
   render () {
     const { intl, hasUnread, hasFollows, columnId, multiColumn } = this.props;
     const pinned = !!columnId;
@@ -80,10 +85,10 @@ class HomeTimeline extends React.PureComponent {
         </ColumnHeader>
 
         <StatusListContainer
-          {...this.props}
           trackScroll={!pinned}
           scrollKey={`home_timeline-${columnId}`}
-          type='home'
+          loadMore={this.handleLoadMore}
+          timelineId='home'
           emptyMessage={emptyMessage}
         />
       </Column>
diff --git a/app/javascript/mastodon/features/public_timeline/index.js b/app/javascript/mastodon/features/public_timeline/index.js
index 2e4fd32a4..02ddb418f 100644
--- a/app/javascript/mastodon/features/public_timeline/index.js
+++ b/app/javascript/mastodon/features/public_timeline/index.js
@@ -5,7 +5,8 @@ import StatusListContainer from '../ui/containers/status_list_container';
 import Column from '../../components/column';
 import ColumnHeader from '../../components/column_header';
 import {
-  refreshTimeline,
+  refreshPublicTimeline,
+  expandPublicTimeline,
   updateTimeline,
   deleteFromTimelines,
   connectTimeline,
@@ -61,7 +62,7 @@ class PublicTimeline extends React.PureComponent {
   componentDidMount () {
     const { dispatch, streamingAPIBaseURL, accessToken } = this.props;
 
-    dispatch(refreshTimeline('public'));
+    dispatch(refreshPublicTimeline());
 
     if (typeof this._subscription !== 'undefined') {
       return;
@@ -106,6 +107,10 @@ class PublicTimeline extends React.PureComponent {
     this.column = c;
   }
 
+  handleLoadMore = () => {
+    this.props.dispatch(expandPublicTimeline());
+  }
+
   render () {
     const { intl, columnId, hasUnread, multiColumn } = this.props;
     const pinned = !!columnId;
@@ -126,8 +131,8 @@ class PublicTimeline extends React.PureComponent {
         </ColumnHeader>
 
         <StatusListContainer
-          {...this.props}
-          type='public'
+          timelineId='public'
+          loadMore={this.handleLoadMore}
           trackScroll={!pinned}
           scrollKey={`public_timeline-${columnId}`}
           emptyMessage={<FormattedMessage id='empty_column.public' defaultMessage='There is nothing here! Write something publicly, or manually follow users from other instances to fill it up' />}
diff --git a/app/javascript/mastodon/features/report/index.js b/app/javascript/mastodon/features/report/index.js
index 25e601f1a..217802b5c 100644
--- a/app/javascript/mastodon/features/report/index.js
+++ b/app/javascript/mastodon/features/report/index.js
@@ -1,7 +1,7 @@
 import React from 'react';
 import { connect } from 'react-redux';
 import { cancelReport, changeReportComment, submitReport } from '../../actions/reports';
-import { fetchAccountTimeline } from '../../actions/accounts';
+import { refreshAccountTimeline } from '../../actions/timelines';
 import PropTypes from 'prop-types';
 import ImmutablePropTypes from 'react-immutable-proptypes';
 import Column from '../ui/components/column';
@@ -28,7 +28,7 @@ const makeMapStateToProps = () => {
       isSubmitting: state.getIn(['reports', 'new', 'isSubmitting']),
       account: getAccount(state, accountId),
       comment: state.getIn(['reports', 'new', 'comment']),
-      statusIds: Immutable.OrderedSet(state.getIn(['timelines', 'accounts_timelines', accountId, 'items'])).union(state.getIn(['reports', 'new', 'status_ids'])),
+      statusIds: Immutable.OrderedSet(state.getIn(['timelines', `account:${accountId}`, 'items'])).union(state.getIn(['reports', 'new', 'status_ids'])),
     };
   };
 
@@ -61,12 +61,12 @@ class Report extends React.PureComponent {
       return;
     }
 
-    this.props.dispatch(fetchAccountTimeline(this.props.account.get('id')));
+    this.props.dispatch(refreshAccountTimeline(this.props.account.get('id')));
   }
 
   componentWillReceiveProps (nextProps) {
     if (this.props.account !== nextProps.account && nextProps.account) {
-      this.props.dispatch(fetchAccountTimeline(nextProps.account.get('id')));
+      this.props.dispatch(refreshAccountTimeline(nextProps.account.get('id')));
     }
   }
 
diff --git a/app/javascript/mastodon/features/status/index.js b/app/javascript/mastodon/features/status/index.js
index 7fc55b795..f8a87ccb1 100644
--- a/app/javascript/mastodon/features/status/index.js
+++ b/app/javascript/mastodon/features/status/index.js
@@ -44,8 +44,8 @@ const makeMapStateToProps = () => {
 
   const mapStateToProps = (state, props) => ({
     status: getStatus(state, Number(props.params.statusId)),
-    ancestorsIds: state.getIn(['timelines', 'ancestors', Number(props.params.statusId)]),
-    descendantsIds: state.getIn(['timelines', 'descendants', Number(props.params.statusId)]),
+    ancestorsIds: state.getIn(['contexts', 'ancestors', Number(props.params.statusId)]),
+    descendantsIds: state.getIn(['contexts', 'descendants', Number(props.params.statusId)]),
     me: state.getIn(['meta', 'me']),
     boostModal: state.getIn(['meta', 'boost_modal']),
     deleteModal: state.getIn(['meta', 'delete_modal']),
diff --git a/app/javascript/mastodon/features/ui/containers/status_list_container.js b/app/javascript/mastodon/features/ui/containers/status_list_container.js
index cbdd2d12d..8d8dc9ba9 100644
--- a/app/javascript/mastodon/features/ui/containers/status_list_container.js
+++ b/app/javascript/mastodon/features/ui/containers/status_list_container.js
@@ -1,6 +1,6 @@
 import { connect } from 'react-redux';
 import StatusList from '../../../components/status_list';
-import { expandTimeline, scrollTopTimeline } from '../../../actions/timelines';
+import { scrollTopTimeline } from '../../../actions/timelines';
 import Immutable from 'immutable';
 import { createSelector } from 'reselect';
 import { debounce } from 'lodash';
@@ -39,31 +39,29 @@ const makeGetStatusIds = () => createSelector([
 const makeMapStateToProps = () => {
   const getStatusIds = makeGetStatusIds();
 
-  const mapStateToProps = (state, props) => ({
-    scrollKey: props.scrollKey,
-    shouldUpdateScroll: props.shouldUpdateScroll,
-    statusIds: getStatusIds(state, props),
-    isLoading: state.getIn(['timelines', props.type, 'isLoading'], true),
-    isUnread: state.getIn(['timelines', props.type, 'unread']) > 0,
-    hasMore: !!state.getIn(['timelines', props.type, 'next']),
+  const mapStateToProps = (state, { timelineId }) => ({
+    statusIds: getStatusIds(state, { type: timelineId }),
+    isLoading: state.getIn(['timelines', timelineId, 'isLoading'], true),
+    isUnread: state.getIn(['timelines', timelineId, 'unread']) > 0,
+    hasMore: !!state.getIn(['timelines', timelineId, 'next']),
   });
 
   return mapStateToProps;
 };
 
-const mapDispatchToProps = (dispatch, { type, id }) => ({
+const mapDispatchToProps = (dispatch, { timelineId, loadMore }) => ({
 
   onScrollToBottom: debounce(() => {
-    dispatch(scrollTopTimeline(type, false));
-    dispatch(expandTimeline(type, id));
+    dispatch(scrollTopTimeline(timelineId, false));
+    loadMore();
   }, 300, { leading: true }),
 
   onScrollToTop: debounce(() => {
-    dispatch(scrollTopTimeline(type, true));
+    dispatch(scrollTopTimeline(timelineId, true));
   }, 100),
 
   onScroll: debounce(() => {
-    dispatch(scrollTopTimeline(type, false));
+    dispatch(scrollTopTimeline(timelineId, false));
   }, 100),
 
 });
diff --git a/app/javascript/mastodon/features/ui/index.js b/app/javascript/mastodon/features/ui/index.js
index 5e70c888c..fe775b434 100644
--- a/app/javascript/mastodon/features/ui/index.js
+++ b/app/javascript/mastodon/features/ui/index.js
@@ -8,7 +8,7 @@ import { connect } from 'react-redux';
 import { isMobile } from '../../is_mobile';
 import { debounce } from 'lodash';
 import { uploadCompose } from '../../actions/compose';
-import { refreshTimeline } from '../../actions/timelines';
+import { refreshHomeTimeline } from '../../actions/timelines';
 import { refreshNotifications } from '../../actions/notifications';
 import UploadArea from './components/upload_area';
 import ColumnsAreaContainer from './containers/columns_area_container';
@@ -95,7 +95,7 @@ class UI extends React.PureComponent {
     document.addEventListener('dragleave', this.handleDragLeave, false);
     document.addEventListener('dragend', this.handleDragEnd, false);
 
-    this.props.dispatch(refreshTimeline('home'));
+    this.props.dispatch(refreshHomeTimeline());
     this.props.dispatch(refreshNotifications());
   }
 
diff --git a/app/javascript/mastodon/reducers/accounts.js b/app/javascript/mastodon/reducers/accounts.js
index d4d9ad62e..7b7074317 100644
--- a/app/javascript/mastodon/reducers/accounts.js
+++ b/app/javascript/mastodon/reducers/accounts.js
@@ -4,8 +4,6 @@ import {
   FOLLOWERS_EXPAND_SUCCESS,
   FOLLOWING_FETCH_SUCCESS,
   FOLLOWING_EXPAND_SUCCESS,
-  ACCOUNT_TIMELINE_FETCH_SUCCESS,
-  ACCOUNT_TIMELINE_EXPAND_SUCCESS,
   FOLLOW_REQUESTS_FETCH_SUCCESS,
   FOLLOW_REQUESTS_EXPAND_SUCCESS,
 } from '../actions/accounts';
@@ -113,8 +111,6 @@ export default function accounts(state = initialState, action) {
     return normalizeAccountsFromStatuses(normalizeAccounts(state, action.accounts), action.statuses);
   case TIMELINE_REFRESH_SUCCESS:
   case TIMELINE_EXPAND_SUCCESS:
-  case ACCOUNT_TIMELINE_FETCH_SUCCESS:
-  case ACCOUNT_TIMELINE_EXPAND_SUCCESS:
   case CONTEXT_FETCH_SUCCESS:
   case FAVOURITED_STATUSES_FETCH_SUCCESS:
   case FAVOURITED_STATUSES_EXPAND_SUCCESS:
diff --git a/app/javascript/mastodon/reducers/accounts_counters.js b/app/javascript/mastodon/reducers/accounts_counters.js
index ea631ceca..eb8a4f83d 100644
--- a/app/javascript/mastodon/reducers/accounts_counters.js
+++ b/app/javascript/mastodon/reducers/accounts_counters.js
@@ -4,8 +4,6 @@ import {
   FOLLOWERS_EXPAND_SUCCESS,
   FOLLOWING_FETCH_SUCCESS,
   FOLLOWING_EXPAND_SUCCESS,
-  ACCOUNT_TIMELINE_FETCH_SUCCESS,
-  ACCOUNT_TIMELINE_EXPAND_SUCCESS,
   FOLLOW_REQUESTS_FETCH_SUCCESS,
   FOLLOW_REQUESTS_EXPAND_SUCCESS,
   ACCOUNT_FOLLOW_SUCCESS,
@@ -115,8 +113,6 @@ export default function accountsCounters(state = initialState, action) {
     return normalizeAccountsFromStatuses(normalizeAccounts(state, action.accounts), action.statuses);
   case TIMELINE_REFRESH_SUCCESS:
   case TIMELINE_EXPAND_SUCCESS:
-  case ACCOUNT_TIMELINE_FETCH_SUCCESS:
-  case ACCOUNT_TIMELINE_EXPAND_SUCCESS:
   case CONTEXT_FETCH_SUCCESS:
   case FAVOURITED_STATUSES_FETCH_SUCCESS:
   case FAVOURITED_STATUSES_EXPAND_SUCCESS:
diff --git a/app/javascript/mastodon/reducers/contexts.js b/app/javascript/mastodon/reducers/contexts.js
new file mode 100644
index 000000000..8a24f5f7a
--- /dev/null
+++ b/app/javascript/mastodon/reducers/contexts.js
@@ -0,0 +1,43 @@
+import { CONTEXT_FETCH_SUCCESS } from '../actions/statuses';
+import { TIMELINE_DELETE } from '../actions/timelines';
+import Immutable from 'immutable';
+
+const initialState = Immutable.Map({
+  ancestors: Immutable.Map(),
+  descendants: Immutable.Map(),
+});
+
+const normalizeContext = (state, id, ancestors, descendants) => {
+  const ancestorsIds   = ancestors.map(ancestor => ancestor.get('id'));
+  const descendantsIds = descendants.map(descendant => descendant.get('id'));
+
+  return state.withMutations(map => {
+    map.setIn(['ancestors', id], ancestorsIds);
+    map.setIn(['descendants', id], descendantsIds);
+  });
+};
+
+const deleteFromContexts = (state, id) => {
+  state.getIn(['descendants', id], Immutable.List()).forEach(descendantId => {
+    state = state.updateIn(['ancestors', descendantId], Immutable.List(), list => list.filterNot(itemId => itemId === id));
+  });
+
+  state.getIn(['ancestors', id], Immutable.List()).forEach(ancestorId => {
+    state = state.updateIn(['descendants', ancestorId], Immutable.List(), list => list.filterNot(itemId => itemId === id));
+  });
+
+  state = state.deleteIn(['descendants', id]).deleteIn(['ancestors', id]);
+
+  return state;
+};
+
+export default function contexts(state = initialState, action) {
+  switch(action.type) {
+  case CONTEXT_FETCH_SUCCESS:
+    return normalizeContext(state, action.id, Immutable.fromJS(action.ancestors), Immutable.fromJS(action.descendants));
+  case TIMELINE_DELETE:
+    return deleteFromContexts(state, action.id);
+  default:
+    return state;
+  }
+};
diff --git a/app/javascript/mastodon/reducers/index.js b/app/javascript/mastodon/reducers/index.js
index c4fe28ea7..be402a16b 100644
--- a/app/javascript/mastodon/reducers/index.js
+++ b/app/javascript/mastodon/reducers/index.js
@@ -17,6 +17,7 @@ import settings from './settings';
 import status_lists from './status_lists';
 import cards from './cards';
 import reports from './reports';
+import contexts from './contexts';
 
 export default combineReducers({
   timelines,
@@ -37,4 +38,5 @@ export default combineReducers({
   settings,
   cards,
   reports,
+  contexts,
 });
diff --git a/app/javascript/mastodon/reducers/statuses.js b/app/javascript/mastodon/reducers/statuses.js
index 7bc3710c4..691135ff7 100644
--- a/app/javascript/mastodon/reducers/statuses.js
+++ b/app/javascript/mastodon/reducers/statuses.js
@@ -21,10 +21,6 @@ import {
   TIMELINE_EXPAND_SUCCESS,
 } from '../actions/timelines';
 import {
-  ACCOUNT_TIMELINE_FETCH_SUCCESS,
-  ACCOUNT_TIMELINE_EXPAND_SUCCESS,
-  ACCOUNT_MEDIA_TIMELINE_FETCH_SUCCESS,
-  ACCOUNT_MEDIA_TIMELINE_EXPAND_SUCCESS,
   ACCOUNT_BLOCK_SUCCESS,
 } from '../actions/accounts';
 import {
@@ -113,10 +109,6 @@ export default function statuses(state = initialState, action) {
     return state.setIn([action.id, 'muted'], false);
   case TIMELINE_REFRESH_SUCCESS:
   case TIMELINE_EXPAND_SUCCESS:
-  case ACCOUNT_TIMELINE_FETCH_SUCCESS:
-  case ACCOUNT_TIMELINE_EXPAND_SUCCESS:
-  case ACCOUNT_MEDIA_TIMELINE_FETCH_SUCCESS:
-  case ACCOUNT_MEDIA_TIMELINE_EXPAND_SUCCESS:
   case CONTEXT_FETCH_SUCCESS:
   case NOTIFICATIONS_REFRESH_SUCCESS:
   case NOTIFICATIONS_EXPAND_SUCCESS:
diff --git a/app/javascript/mastodon/reducers/timelines.js b/app/javascript/mastodon/reducers/timelines.js
index ab756b854..2bc1c8050 100644
--- a/app/javascript/mastodon/reducers/timelines.js
+++ b/app/javascript/mastodon/reducers/timelines.js
@@ -18,228 +18,79 @@ import {
   UNFAVOURITE_SUCCESS,
 } from '../actions/interactions';
 import {
-  ACCOUNT_TIMELINE_FETCH_REQUEST,
-  ACCOUNT_TIMELINE_FETCH_SUCCESS,
-  ACCOUNT_TIMELINE_FETCH_FAIL,
-  ACCOUNT_TIMELINE_EXPAND_REQUEST,
-  ACCOUNT_TIMELINE_EXPAND_SUCCESS,
-  ACCOUNT_TIMELINE_EXPAND_FAIL,
-  ACCOUNT_MEDIA_TIMELINE_FETCH_REQUEST,
-  ACCOUNT_MEDIA_TIMELINE_FETCH_SUCCESS,
-  ACCOUNT_MEDIA_TIMELINE_FETCH_FAIL,
-  ACCOUNT_MEDIA_TIMELINE_EXPAND_REQUEST,
-  ACCOUNT_MEDIA_TIMELINE_EXPAND_SUCCESS,
-  ACCOUNT_MEDIA_TIMELINE_EXPAND_FAIL,
   ACCOUNT_BLOCK_SUCCESS,
   ACCOUNT_MUTE_SUCCESS,
 } from '../actions/accounts';
-import {
-  CONTEXT_FETCH_SUCCESS,
-} from '../actions/statuses';
 import Immutable from 'immutable';
 
-const initialState = Immutable.Map({
-  home: Immutable.Map({
-    path: () => '/api/v1/timelines/home',
-    next: null,
-    isLoading: false,
-    online: false,
-    loaded: false,
-    top: true,
-    unread: 0,
-    items: Immutable.List(),
-  }),
-
-  public: Immutable.Map({
-    path: () => '/api/v1/timelines/public',
-    next: null,
-    isLoading: false,
-    online: false,
-    loaded: false,
-    top: true,
-    unread: 0,
-    items: Immutable.List(),
-  }),
-
-  community: Immutable.Map({
-    path: () => '/api/v1/timelines/public',
-    next: null,
-    params: { local: true },
-    isLoading: false,
-    online: false,
-    loaded: false,
-    top: true,
-    unread: 0,
-    items: Immutable.List(),
-  }),
+const initialState = Immutable.Map();
 
-  tag: Immutable.Map({
-    path: (id) => `/api/v1/timelines/tag/${id}`,
-    next: null,
-    isLoading: false,
-    id: null,
-    loaded: false,
-    top: true,
-    unread: 0,
-    items: Immutable.List(),
-  }),
-
-  accounts_timelines: Immutable.Map(),
-  accounts_media_timelines: Immutable.Map(),
-  ancestors: Immutable.Map(),
-  descendants: Immutable.Map(),
+const initialTimeline = Immutable.Map({
+  unread: 0,
+  online: false,
+  top: true,
+  loaded: false,
+  isLoading: false,
+  next: false,
+  items: Immutable.List(),
 });
 
-const normalizeStatus = (state, status) => {
-  return state;
-};
-
 const normalizeTimeline = (state, timeline, statuses, next) => {
-  let ids      = Immutable.List();
-  const loaded = state.getIn([timeline, 'loaded']);
-
-  statuses.forEach((status, i) => {
-    state = normalizeStatus(state, status);
-    ids   = ids.set(i, status.get('id'));
-  });
-
-  state = state.setIn([timeline, 'loaded'], true);
-  state = state.setIn([timeline, 'isLoading'], false);
-
-  if (state.getIn([timeline, 'next']) === null) {
-    state = state.setIn([timeline, 'next'], next);
-  }
-
-  return state.updateIn([timeline, 'items'], Immutable.List(), list => (loaded ? ids.concat(list) : ids));
+  const ids       = Immutable.List(statuses.map(status => status.get('id')));
+  const wasLoaded = state.getIn([timeline, 'loaded']);
+  const hadNext   = state.getIn([timeline, 'next']);
+  const oldIds    = state.getIn([timeline, 'items'], Immutable.List());
+
+  return state.update(timeline, initialTimeline, map => map.withMutations(mMap => {
+    mMap.set('loaded', true);
+    mMap.set('isLoading', false);
+    if (!hadNext) mMap.set('next', next);
+    mMap.set('items', wasLoaded ? ids.concat(oldIds) : ids);
+  }));
 };
 
 const appendNormalizedTimeline = (state, timeline, statuses, next) => {
-  let moreIds = Immutable.List();
-
-  statuses.forEach((status, i) => {
-    state   = normalizeStatus(state, status);
-    moreIds = moreIds.set(i, status.get('id'));
-  });
-
-  state = state.setIn([timeline, 'isLoading'], false);
-  state = state.setIn([timeline, 'next'], next);
-
-  return state.updateIn([timeline, 'items'], Immutable.List(), list => list.concat(moreIds));
-};
-
-const normalizeAccountTimeline = (state, accountId, statuses, replace, next) => {
-  let ids = Immutable.List();
-
-  statuses.forEach((status, i) => {
-    state = normalizeStatus(state, status);
-    ids   = ids.set(i, status.get('id'));
-  });
-
-  return state.updateIn(['accounts_timelines', accountId], Immutable.Map(), map => map
-    .set('isLoading', false)
-    .set('loaded', true)
-    .update('next', null, v => replace ? next : v)
-    .update('items', Immutable.List(), list => (replace ? ids : ids.concat(list))));
-};
-
-const normalizeAccountMediaTimeline = (state, accountId, statuses, replace, next) => {
-  let ids = Immutable.List();
-
-  statuses.forEach((status, i) => {
-    state = normalizeStatus(state, status);
-    ids   = ids.set(i, status.get('id'));
-  });
-
-  return state.updateIn(['accounts_media_timelines', accountId], Immutable.Map(), map => map
-    .set('isLoading', false)
-    .update('next', null, v => replace ? next : v)
-    .update('items', Immutable.List(), list => (replace ? ids : ids.concat(list))));
-};
-
-const appendNormalizedAccountTimeline = (state, accountId, statuses, next) => {
-  let moreIds = Immutable.List([]);
-
-  statuses.forEach((status, i) => {
-    state   = normalizeStatus(state, status);
-    moreIds = moreIds.set(i, status.get('id'));
-  });
-
-  return state.updateIn(['accounts_timelines', accountId], Immutable.Map(), map => map
-    .set('isLoading', false)
-    .set('next', next)
-    .update('items', list => list.concat(moreIds)));
-};
-
-const appendNormalizedAccountMediaTimeline = (state, accountId, statuses, next) => {
-  let moreIds = Immutable.List([]);
-
-  statuses.forEach((status, i) => {
-    state   = normalizeStatus(state, status);
-    moreIds = moreIds.set(i, status.get('id'));
-  });
-
-  return state.updateIn(['accounts_media_timelines', accountId], Immutable.Map(), map => map
-    .set('isLoading', false)
-    .set('next', next)
-    .update('items', list => list.concat(moreIds)));
+  const ids    = Immutable.List(statuses.map(status => status.get('id')));
+  const oldIds = state.getIn([timeline, 'items'], Immutable.List());
+
+  return state.update(timeline, initialTimeline, map => map.withMutations(mMap => {
+    mMap.set('isLoading', false);
+    mMap.set('next', next);
+    mMap.set('items', oldIds.concat(ids));
+  }));
 };
 
 const updateTimeline = (state, timeline, status, references) => {
-  const top = state.getIn([timeline, 'top']);
+  const top        = state.getIn([timeline, 'top']);
+  const ids        = state.getIn([timeline, 'items'], Immutable.List());
+  const includesId = ids.includes(status.get('id'));
+  const unread     = state.getIn([timeline, 'unread'], 0);
 
-  state = normalizeStatus(state, status);
-
-  if (!top) {
-    state = state.updateIn([timeline, 'unread'], unread => unread + 1);
+  if (includesId) {
+    return state;
   }
 
-  state = state.updateIn([timeline, 'items'], Immutable.List(), list => {
-    if (top && list.size > 40) {
-      list = list.take(20);
-    }
-
-    if (list.includes(status.get('id'))) {
-      return list;
-    }
-
-    const reblogOfId = status.getIn(['reblog', 'id'], null);
+  let newIds = ids;
 
-    if (reblogOfId !== null) {
-      list = list.filterNot(itemId => references.includes(itemId));
-    }
-
-    return list.unshift(status.get('id'));
-  });
-
-  return state;
+  return state.update(timeline, initialTimeline, map => map.withMutations(mMap => {
+    if (!top) mMap.set('unread', unread + 1);
+    if (top && ids.size > 40) newIds = newIds.take(20);
+    if (status.getIn(['reblog', 'id'], null) !== null) newIds = newIds.filterNot(item => references.includes(item));
+    mMap.set('items', newIds.unshift(status.get('id')));
+  }));
 };
 
 const deleteStatus = (state, id, accountId, references, reblogOf) => {
-  if (reblogOf) {
-    // If we are deleting a reblog, just replace reblog with its original
-    return state.updateIn(['home', 'items'], list => list.map(item => item === id ? reblogOf : item));
-  }
-
-  // Remove references from timelines
-  ['home', 'public', 'community', 'tag'].forEach(function (timeline) {
-    state = state.updateIn([timeline, 'items'], list => list.filterNot(item => item === id));
+  state.keySeq().forEach(timeline => {
+    state = state.updateIn([timeline, 'items'], list => {
+      if (reblogOf && !list.includes(reblogOf)) {
+        return list.map(item => item === id ? reblogOf : item);
+      } else {
+        return list.filterNot(item => item === id);
+      }
+    });
   });
 
-  // Remove references from account timelines
-  state = state.updateIn(['accounts_timelines', accountId, 'items'], Immutable.List([]), list => list.filterNot(item => item === id));
-  state = state.updateIn(['accounts_media_timelines', accountId, 'items'], Immutable.List([]), list => list.filterNot(item => item === id));
-
-  // Remove references from context
-  state.getIn(['descendants', id], Immutable.List()).forEach(descendantId => {
-    state = state.updateIn(['ancestors', descendantId], Immutable.List(), list => list.filterNot(itemId => itemId === id));
-  });
-
-  state.getIn(['ancestors', id], Immutable.List()).forEach(ancestorId => {
-    state = state.updateIn(['descendants', ancestorId], Immutable.List(), list => list.filterNot(itemId => itemId === id));
-  });
-
-  state = state.deleteIn(['descendants', id]).deleteIn(['ancestors', id]);
-
   // Remove reblogs of deleted status
   references.forEach(ref => {
     state = deleteStatus(state, ref[0], ref[1], []);
@@ -257,54 +108,27 @@ const filterTimelines = (state, relationship, statuses) => {
     }
 
     references = statuses.filter(item => item.get('reblog') === status.get('id')).map(item => [item.get('id'), item.get('account')]);
-    state = deleteStatus(state, status.get('id'), status.get('account'), references);
-  });
-
-  return state;
-};
-
-const normalizeContext = (state, id, ancestors, descendants) => {
-  const ancestorsIds   = ancestors.map(ancestor => ancestor.get('id'));
-  const descendantsIds = descendants.map(descendant => descendant.get('id'));
-
-  return state.withMutations(map => {
-    map.setIn(['ancestors', id], ancestorsIds);
-    map.setIn(['descendants', id], descendantsIds);
+    state      = deleteStatus(state, status.get('id'), status.get('account'), references);
   });
-};
-
-const resetTimeline = (state, timeline, id) => {
-  if (timeline === 'tag' && typeof id !== 'undefined' && state.getIn([timeline, 'id']) !== id) {
-    state = state.update(timeline, map => map
-        .set('id', id)
-        .set('isLoading', true)
-        .set('loaded', false)
-        .set('next', null)
-        .set('top', true)
-        .update('items', list => list.clear()));
-  } else {
-    state = state.setIn([timeline, 'isLoading'], true);
-  }
 
   return state;
 };
 
 const updateTop = (state, timeline, top) => {
-  if (top) {
-    state = state.setIn([timeline, 'unread'], 0);
-  }
-
-  return state.setIn([timeline, 'top'], top);
+  return state.update(timeline, initialTimeline, map => map.withMutations(mMap => {
+    if (top) mMap.set('unread', 0);
+    mMap.set('top', top);
+  }));
 };
 
 export default function timelines(state = initialState, action) {
   switch(action.type) {
   case TIMELINE_REFRESH_REQUEST:
   case TIMELINE_EXPAND_REQUEST:
-    return resetTimeline(state, action.timeline, action.id);
+    return state.update(action.timeline, initialTimeline, map => map.set('isLoading', true));
   case TIMELINE_REFRESH_FAIL:
   case TIMELINE_EXPAND_FAIL:
-    return state.setIn([action.timeline, 'isLoading'], false);
+    return state.update(action.timeline, initialTimeline, map => map.set('isLoading', false));
   case TIMELINE_REFRESH_SUCCESS:
     return normalizeTimeline(state, action.timeline, Immutable.fromJS(action.statuses), action.next);
   case TIMELINE_EXPAND_SUCCESS:
@@ -313,37 +137,15 @@ export default function timelines(state = initialState, action) {
     return updateTimeline(state, action.timeline, Immutable.fromJS(action.status), action.references);
   case TIMELINE_DELETE:
     return deleteStatus(state, action.id, action.accountId, action.references, action.reblogOf);
-  case CONTEXT_FETCH_SUCCESS:
-    return normalizeContext(state, action.id, Immutable.fromJS(action.ancestors), Immutable.fromJS(action.descendants));
-  case ACCOUNT_TIMELINE_FETCH_REQUEST:
-  case ACCOUNT_TIMELINE_EXPAND_REQUEST:
-    return state.updateIn(['accounts_timelines', action.id], Immutable.Map(), map => map.set('isLoading', true));
-  case ACCOUNT_TIMELINE_FETCH_FAIL:
-  case ACCOUNT_TIMELINE_EXPAND_FAIL:
-    return state.updateIn(['accounts_timelines', action.id], Immutable.Map(), map => map.set('isLoading', false));
-  case ACCOUNT_TIMELINE_FETCH_SUCCESS:
-    return normalizeAccountTimeline(state, action.id, Immutable.fromJS(action.statuses), action.replace, action.next);
-  case ACCOUNT_TIMELINE_EXPAND_SUCCESS:
-    return appendNormalizedAccountTimeline(state, action.id, Immutable.fromJS(action.statuses), action.next);
-  case ACCOUNT_MEDIA_TIMELINE_FETCH_REQUEST:
-  case ACCOUNT_MEDIA_TIMELINE_EXPAND_REQUEST:
-    return state.updateIn(['accounts_media_timelines', action.id], Immutable.Map(), map => map.set('isLoading', true));
-  case ACCOUNT_MEDIA_TIMELINE_FETCH_FAIL:
-  case ACCOUNT_MEDIA_TIMELINE_EXPAND_FAIL:
-    return state.updateIn(['accounts_media_timelines', action.id], Immutable.Map(), map => map.set('isLoading', false));
-  case ACCOUNT_MEDIA_TIMELINE_FETCH_SUCCESS:
-    return normalizeAccountMediaTimeline(state, action.id, Immutable.fromJS(action.statuses), action.replace, action.next);
-  case ACCOUNT_MEDIA_TIMELINE_EXPAND_SUCCESS:
-    return appendNormalizedAccountMediaTimeline(state, action.id, Immutable.fromJS(action.statuses), action.next);
   case ACCOUNT_BLOCK_SUCCESS:
   case ACCOUNT_MUTE_SUCCESS:
     return filterTimelines(state, action.relationship, action.statuses);
   case TIMELINE_SCROLL_TOP:
     return updateTop(state, action.timeline, action.top);
   case TIMELINE_CONNECT:
-    return state.setIn([action.timeline, 'online'], true);
+    return state.update(action.timeline, initialTimeline, map => map.set('online', true));
   case TIMELINE_DISCONNECT:
-    return state.setIn([action.timeline, 'online'], false);
+    return state.update(action.timeline, initialTimeline, map => map.set('online', false));
   default:
     return state;
   }
diff --git a/app/javascript/mastodon/selectors/index.js b/app/javascript/mastodon/selectors/index.js
index 0d2ef2ea9..d5d736e2f 100644
--- a/app/javascript/mastodon/selectors/index.js
+++ b/app/javascript/mastodon/selectors/index.js
@@ -76,7 +76,7 @@ export const makeGetNotification = () => {
 };
 
 export const getAccountGallery = createSelector([
-  (state, id) => state.getIn(['timelines', 'accounts_media_timelines', id, 'items'], Immutable.List()),
+  (state, id) => state.getIn(['timelines', `account:${id}:media`, 'items'], Immutable.List()),
   state       => state.get('statuses'),
 ], (statusIds, statuses) => {
   let medias = Immutable.List();