zulip/static/js/message_list_view.js

691 lines
28 KiB
JavaScript

function MessageListView(list, table_name, collapse_messages) {
this.list = list;
this.collapse_messages = collapse_messages;
this._rows = {};
this.table_name = table_name;
if (this.table_name) {
this.clear_table();
}
this._message_groups = [];
// Half-open interval of the indices that define the current render window
this._render_win_start = 0;
this._render_win_end = 0;
}
(function () {
function stringify_time(time) {
if (feature_flags.twenty_four_hour_time) {
return time.toString('HH:mm');
}
return time.toString('h:mm TT');
}
function same_day(earlier_msg, later_msg) {
var earlier_time = new XDate(earlier_msg.timestamp * 1000);
var later_time = new XDate(later_msg.timestamp * 1000);
return earlier_time.toDateString() === later_time.toDateString();
}
function add_display_time(group, message, prev) {
var time = new XDate(message.timestamp * 1000);
if (prev !== undefined) {
var prev_time = new XDate(prev.timestamp * 1000);
if (time.toDateString() !== prev_time.toDateString()) {
// NB: show_date is HTML, inserted into the document without escaping.
group.show_date = (timerender.render_date(time, prev_time))[0].outerHTML;
}
} else {
group.show_date = (timerender.render_date(time))[0].outerHTML;
}
if (message.timestr === undefined) {
message.timestr = stringify_time(time);
}
}
MessageListView.prototype = {
// Number of messages to render at a time
_RENDER_WINDOW_SIZE: 400,
// Number of messages away from edge of render window at which we
// trigger a re-render
_RENDER_THRESHOLD: 50,
render: function MessageListView__render(messages, where, messages_are_new) {
var list = this.list; // for convenience
// This function processes messages into chunks with separators between them,
// and templates them to be inserted as table rows into the DOM.
if (messages.length === 0 || this.table_name === undefined) {
return;
}
function start_group() {
return {messages: []};
}
var table_name = this.table_name;
var table = rows.get_table(table_name);
// we we record if last_message_was_selected before updating the table
var last_message_was_selected = rows.id(rows.last_visible()) === list.selected_id();
var ids_where_next_is_same_sender = {};
var prev;
var orig_scrolltop_offset, last_message_id;
var combined_messages, first_msg, last_msg;
var current_group = start_group();
var new_message_groups = [];
var self = this;
if (where === "bottom") {
// Remove the trailing bookend; it'll be re-added after we do our rendering
self.clear_trailing_bookend();
} else if (self.selected_row().length > 0) {
orig_scrolltop_offset = self.selected_row().offset().top;
}
if (where === 'top' && self.collapse_messages && this._message_groups.length > 0) {
// Remove the top date_row, we'll re-add it after rendering
$('.date_row:first', table).remove();
// Delete the current top message group, and add it back in with these
// messages, in order to collapse properly.
//
// This means we redraw the entire view on each backfill-update when narrowed by
// subject, which could be a problem down the line. For now we hope
// that subject views will not be very big.
var top_group = self._message_groups[0];
rows.get_message_recipient_row(this.get_row(top_group.messages[0].id)).remove();
messages = messages.concat(top_group.messages);
}
if (where !== 'top') {
var last_row = table.find('div[zid]:last');
last_message_id = rows.id(last_row);
prev = self.get_message(last_message_id);
}
function add_message_to_group(message) {
current_group.messages.push(message);
}
function finish_group() {
if (current_group.messages.length > 0) {
var first_message = current_group.messages[0];
current_group.is_stream = first_message.is_stream;
current_group.is_private = first_message.is_private;
if (current_group.is_stream) {
current_group.background_color = stream_data.get_color(first_message.stream);
current_group.color_class = stream_color.get_color_class(current_group.background_color);
current_group.invite_only = stream_data.get_invite_only(first_message.stream);
current_group.subject = first_message.subject;
} else if (current_group.is_private) {
current_group.pm_with_url = first_message.pm_with_url;
current_group.display_reply_to = first_message.display_reply_to;
}
current_group.display_recipient = first_message.display_recipient;
current_group.always_visible_topic_edit = first_message.always_visible_topic_edit;
current_group.subject_links = first_message.subject_links;
current_group.messages[current_group.messages.length - 1].include_footer = true;
new_message_groups.push(current_group);
}
}
function add_subscription_marker(group, last_msg, first_msg) {
if (last_msg !== undefined &&
first_msg.historical !== last_msg.historical) {
group.bookend_top = true;
if (first_msg.historical) {
group.unsubscribed = first_msg.stream;
group.bookend_content = self.list.unsubscribed_bookend_content(first_msg.stream);
} else {
group.subscribed = first_msg.stream;
group.bookend_content = self.list.subscribed_bookend_content(first_msg.stream);
}
}
}
_.each(messages, function (message) {
message.include_recipient = false;
message.include_footer = false;
if (util.same_recipient(prev, message) && self.collapse_messages &&
prev.historical === message.historical && same_day(prev, message)) {
add_message_to_group(message);
} else {
finish_group();
current_group = start_group();
add_message_to_group(message);
message.include_recipient = true;
message.subscribed = false;
message.unsubscribed = false;
// This home_msg_list condition can be removed
// once we filter historical messages from the
// home view on the server side (which requires
// having an index on UserMessage.flags)
if (self.list !== home_msg_list) {
add_subscription_marker(current_group, prev, message);
}
if (message.stream) {
message.stream_url = narrow.by_stream_uri(message.stream);
message.topic_url = narrow.by_stream_subject_uri(message.stream, message.subject);
} else {
message.pm_with_url = narrow.pm_with_uri(message.reply_to);
}
}
add_display_time(current_group, message, prev);
message.include_sender = true;
if (!message.include_recipient &&
!prev.status_message &&
util.same_sender(prev, message)) {
message.include_sender = false;
ids_where_next_is_same_sender[prev.id] = true;
}
self._add_msg_timestring(message);
message.dom_id = table_name + message.id;
message.small_avatar_url = ui.small_avatar_url(message);
if (message.stream !== undefined) {
message.background_color = stream_data.get_color(message.stream);
}
message.contains_mention = notifications.speaking_at_me(message);
message.unread = unread.message_unread(message);
if (message.is_me_message) {
// Slice the '<p>/me ' off the front, and '</p>' off the end
message.status_message = message.content.slice(4 + 3, -4);
message.include_sender = true;
}
else {
message.status_message = false;
}
prev = message;
// This home_msg_list condition can be removed
// once we filter historical messages from the
// home view on the server side (which requires
// having an index on UserMessage.flags)
if (self.list !== home_msg_list) {
list.last_message_historical = message.historical;
}
});
finish_group();
if (new_message_groups.length === 0 ||
new_message_groups[new_message_groups.length - 1].messages.length === 0) {
return;
}
if (where === 'top') {
// If we prepended messages that are historical, show the subscription message
if (self._message_groups.length === 0 ||
(prev.historical !== self._message_groups[0].messages[0].historical)) {
if (self.list !== home_msg_list) {
current_group.bookend_bottom = true;
add_subscription_marker(current_group, prev, self._message_groups[0].messages[0]);
}
}
}
var rendered_groups = $(templates.render('message_group', {
message_groups: new_message_groups
}));
var rendered_messages = [];
_.each(rendered_groups, function (group) {
_.each($('div.message_row', group), function (message_row) {
var row = $(message_row);
// Save DOM elements by id into self._rows for O(1) lookup
if (row.hasClass('message_row')) {
self._rows[row.attr('zid')] = message_row;
}
if (row.hasClass('mention')) {
row.find('.user-mention').each(function () {
var email = $(this).attr('data-user-email');
if (email === '*' || email === page_params.email) {
$(this).addClass('user-mention-me');
}
});
}
rendered_messages.push(message_row);
});
});
// The message that was last before this batch came in has to be
// handled specially because we didn't just render it and
// therefore have to lookup its associated element
// If the previous message was part of the same block but
// had a footer, we need to remove it.
if (last_message_id !== undefined) {
var row = self.get_row(last_message_id);
if (ids_where_next_is_same_sender[last_message_id]) {
row.find('.messagebox').addClass("next_is_same_sender");
}
}
_.each(rendered_messages, function (elem){
var e = $.Event('message_rendered.zulip', {target: elem});
$(document).trigger(e);
});
function first_group_message(groups) {
var first_group = groups[0];
return first_group.messages[0];
}
function last_group_message(groups) {
var last_group = groups[groups.length - 1];
return last_group.messages[last_group.messages.length - 1];
}
function combine_adjacent_groups(before_list, after_list) {
// Given two lists of message groups,
// returns: one list that has the abutting groups' message list messages
var combined_messages = before_list[before_list.length - 1].messages.concat(after_list[0].messages);
before_list[before_list.length - 1].messages = combined_messages;
return before_list.concat(after_list.slice(1));
}
if (self._message_groups.length === 0) {
self._message_groups = new_message_groups;
table.append(rendered_groups);
} else {
if (where === 'top') {
self._message_groups = new_message_groups.concat(self._message_groups);
table.prepend(rendered_groups);
} else {
// When appending messages, since we're not re-rendering the whole existing last block of messages,
// we may have to insert the messages in the existing block. We do this if the messages would normally
// have been in the same group originally
last_msg = last_group_message(self._message_groups);
first_msg = first_group_message(new_message_groups);
if (self.collapse_messages && util.same_recipient(last_msg, first_msg) && same_day(last_msg, first_msg)) {
self._message_groups = combine_adjacent_groups(self._message_groups, new_message_groups);
// Pluck the merged messages out of our rendered group list, and insert them
// into the existing group div
var last_group = rows.get_message_recipient_row(self._rows[last_msg.id]);
last_group.find('.last_message').removeClass('last_message');
last_group.append($('.message_row', rendered_groups[0]).remove());
rendered_groups.splice(0, 1);
} else {
self._message_groups = self._message_groups.concat(new_message_groups);
}
// append the rest of the groups
table.append(rendered_groups);
}
}
list.update_trailing_bookend();
_.each(rendered_messages, function (elem) {
var row = $(elem);
var id = rows.id(row);
message_edit.maybe_show_edit(row, id);
});
// Must happen after the elements are inserted into the document for
// getBoundingClientRect to work.
// Also, the list must actually be visible.
if (list === current_msg_list) {
ui.condense_and_collapse(rendered_messages);
}
// Must happen after anything that changes the height of messages has
// taken effect.
if (where === 'top' && list === current_msg_list && orig_scrolltop_offset !== undefined) {
// Restore the selected row to its original position in
// relation to the top of the window
viewport.set_message_offset(orig_scrolltop_offset);
list.reselect_selected_id();
}
if (list === current_msg_list) {
// Update the fade.
var get_element = function (message_group) {
// We don't have a MessageGroup class, but we can at least hide the messy details
// of rows.js from compose_fade. We provide a callback function to be lazy--
// compose_fade may not actually need the elements depending on its internal
// state.
var message_row = self.get_row(message_group.messages[0].id);
return rows.get_message_recipient_row(message_row);
};
compose_fade.update_rendered_message_groups(new_message_groups, get_element);
}
if (list === current_msg_list && messages_are_new) {
self._maybe_autoscroll(rendered_messages, last_message_was_selected);
}
},
_add_msg_timestring: function MessageListView__add_msg_timestring(message) {
if (message.last_edit_timestamp !== undefined) {
// Add or update the last_edit_timestr
var last_edit_time = new XDate(message.last_edit_timestamp * 1000);
message.last_edit_timestr =
(timerender.render_date(last_edit_time))[0].innerText
+ " at " + stringify_time(last_edit_time);
}
},
_maybe_autoscroll: function MessageListView__maybe_autoscroll(rendered_elems, last_message_was_selected) {
// If we are near the bottom of our feed (the bottom is visible) and can
// scroll up without moving the pointer out of the viewport, do so, by
// up to the amount taken up by the new message.
var new_messages_height = 0;
var distance_to_last_message_sent_by_me = 0;
var id_of_last_message_sent_by_us = -1;
// C++ iterators would have made this less painful
_.each(rendered_elems.reverse(), function (elem) {
// Sometimes there are non-DOM elements in rendered_elems; only
// try to get the heights of actual trs.
if ($(elem).is("div")) {
new_messages_height += elem.offsetHeight;
// starting from the last message, ignore message heights that weren't sent by me.
if(id_of_last_message_sent_by_us > -1) {
distance_to_last_message_sent_by_me += elem.offsetHeight;
return;
}
var row_id = rows.id($(elem));
// check for `row_id` NaN in case we're looking at a date row or bookend row
if (row_id > -1 &&
this.get_message(row_id).sender_email === page_params.email)
{
distance_to_last_message_sent_by_me += elem.offsetHeight;
id_of_last_message_sent_by_us = rows.id($(elem));
}
}
}, this);
// autoscroll_forever: if we're on the last message, keep us on the last message
if (last_message_was_selected && page_params.autoscroll_forever) {
this.list.select_id(this.list.last().id, {from_rendering: true});
scroll_to_selected();
this.list.reselect_selected_id();
return;
}
var selected_row = this.selected_row();
var last_visible = rows.last_visible();
// Make sure we have a selected row and last visible row. (defensive)
if (!(selected_row && (selected_row.length > 0) && last_visible)) {
return;
}
var selected_row_offset = selected_row.offset().top;
var info = viewport.message_viewport_info();
var available_space_for_scroll = selected_row_offset - info.visible_top;
// autoscroll_forever: if we've sent a message, move pointer at least that far.
if (page_params.autoscroll_forever && id_of_last_message_sent_by_us > -1 && (rows.last_visible().offset().top - this.list.selected_row().offset().top) < (viewport.height())) {
this.list.select_id(id_of_last_message_sent_by_us, {from_rendering: true});
scroll_to_selected();
return;
}
// Don't scroll if we can't move the pointer up.
if (available_space_for_scroll <= 0) {
return;
}
if (new_messages_height <= 0) {
return;
}
// This next decision is fairly debatable. For a big message that
// would push the pointer off the screen, we do a partial autoscroll,
// which has the following implications:
// a) user sees scrolling (good)
// b) user's pointer stays on screen (good)
// c) scroll amount isn't really tied to size of new messages (bad)
// d) all the bad things about scrolling for users who want messages
// to stay on the screen
var scroll_amount = new_messages_height;
if (scroll_amount > available_space_for_scroll) {
scroll_amount = available_space_for_scroll;
}
// Let's work our way back to whether the user was already dealing
// with messages off the screen, in which case we shouldn't autoscroll.
var bottom_last_visible = last_visible.offset().top + last_visible.height();
var bottom_old_last_visible = bottom_last_visible - new_messages_height;
var bottom_viewport = info.visible_top + info.visible_height;
// Exit if the user was already past the bottom.
if (bottom_old_last_visible > bottom_viewport) {
return;
}
// Ok, we are finally ready to actually scroll.
viewport.system_initiated_animate_scroll(scroll_amount);
},
clear_rendering_state: function MessageListView__clear_rendering_state(clear_table) {
this._message_groups = [];
if (clear_table) {
this.clear_table();
}
this.list.last_message_historical = false;
this._render_win_start = 0;
this._render_win_end = 0;
},
update_render_window: function MessageListView__update_render_window(selected_idx, check_for_changed) {
var new_start = Math.max(selected_idx - this._RENDER_WINDOW_SIZE / 2, 0);
if (check_for_changed && new_start === this._render_win_start) {
return false;
}
this._render_win_start = new_start;
this._render_win_end = Math.min(this._render_win_start + this._RENDER_WINDOW_SIZE,
this.list.num_items());
return true;
},
maybe_rerender: function MessageListView__maybe_rerender() {
if (this.table_name === undefined) {
return false;
}
var selected_idx = this.list.selected_idx();
// We rerender under the following conditions:
// * The selected message is within this._RENDER_THRESHOLD messages
// of the top of the currently rendered window and the top
// of the window does not abut the beginning of the message
// list
// * The selected message is within this._RENDER_THRESHOLD messages
// of the bottom of the currently rendered window and the
// bottom of the window does not abut the end of the
// message list
if (! (((selected_idx - this._render_win_start < this._RENDER_THRESHOLD)
&& (this._render_win_start !== 0)) ||
((this._render_win_end - selected_idx <= this._RENDER_THRESHOLD)
&& (this._render_win_end !== this.list.num_items()))))
{
return false;
}
if (!this.update_render_window(selected_idx, true)) {
return false;
}
this.rerender_preserving_scrolltop();
return true;
},
rerender_preserving_scrolltop: function MessageListView__rerender_preserving_scrolltop() {
// scrolltop_offset is the number of pixels between the top of the
// viewable window and the newly selected message
var scrolltop_offset;
var selected_row = this.selected_row();
var selected_in_view = (selected_row.length > 0);
if (selected_in_view) {
scrolltop_offset = viewport.scrollTop() - selected_row.offset().top;
}
this.clear_table();
this.render(this.list.all().slice(this._render_win_start,
this._render_win_end), 'bottom');
// If we could see the newly selected message, scroll the
// window such that the newly selected message is at the
// same location as it would have been before we
// re-rendered.
if (selected_in_view) {
// Must get this.list.selected_row() again since it is now a new DOM element
viewport.scrollTop(this.selected_row().offset().top + scrolltop_offset);
}
},
rerender_message: function MessageListView__rerender_message(message) {
var row = this.get_row(message.id);
var was_selected = this.list.selected_message() === message;
if (row === undefined) {
blueslip.error("Cannot rerender a message that's not in this list!");
return;
}
// Re-render just this one message
this._add_msg_timestring(message);
var rendered_msg = $(templates.render('single_message', message));
this._rows[message.id] = rendered_msg;
row.replaceWith(rendered_msg);
if (was_selected) {
this.list.select_id(message.id);
}
},
rerender_messages: function MessageListView__rerender_messages(messages) {
var self = this;
_.each(messages, function (message) {
self.rerender_message(message);
});
},
append: function MessageListView__append(messages, messages_are_new) {
var cur_window_size = this._render_win_end - this._render_win_start;
if (cur_window_size < this._RENDER_WINDOW_SIZE) {
var slice_to_render = messages.slice(0, this._RENDER_WINDOW_SIZE - cur_window_size);
this.render(slice_to_render, 'bottom', messages_are_new);
this._render_win_end += slice_to_render.length;
}
// If the pointer is high on the page such that there is a
// lot of empty space below and the render window is full, a
// newly recieved message should trigger a rerender so that
// the new message, which will appear in the viewable area,
// is rendered.
this.maybe_rerender();
},
prepend: function MessageListView__prepend(messages) {
this._render_win_start += messages.length;
this._render_win_end += messages.length;
var cur_window_size = this._render_win_end - this._render_win_start;
if (cur_window_size < this._RENDER_WINDOW_SIZE) {
var msgs_to_render_count = this._RENDER_WINDOW_SIZE - cur_window_size;
var slice_to_render = messages.slice(messages.length - msgs_to_render_count);
this.render(slice_to_render, 'top', false);
this._render_win_start -= slice_to_render.length;
}
},
rerender_the_whole_thing: function MessageListView__rerender_the_whole_thing(messages) {
// TODO: Figure out if we can unify this with this.list.rerender().
this.clear_rendering_state(true);
this.update_render_window(this.list.selected_idx(), false);
this.render(this.list.all().slice(this._render_win_start,
this._render_win_end), 'bottom');
},
clear_table: function MessageListView_clear_table() {
// We do not want to call .empty() because that also clears
// jQuery data. This does mean, however, that we need to be
// mindful of memory leaks.
rows.get_table(this.table_name).children().detach();
this._rows = {};
},
get_row: function MessageListView_get_row(id) {
return $(this._rows[id]);
},
clear_trailing_bookend: function MessageListView_clear_trailing_bookend() {
var trailing_bookend = rows.get_table(this.table_name).find('.trailing_bookend');
trailing_bookend.remove();
},
render_trailing_bookend: function MessageListView_render_trailing_bookend(trailing_bookend_content) {
var rendered_trailing_bookend = $(templates.render('bookend', {
bookend_content: trailing_bookend_content,
trailing: true
}));
rows.get_table(this.table_name).append(rendered_trailing_bookend);
},
selected_row: function MessageListView_selected_row() {
return this.get_row(this.list.selected_id());
},
get_message: function MessageListView_get_message(id) {
return this.list.get(id);
},
change_message_id: function MessageListView_change_message_id(old_id, new_id) {
if (this._rows[old_id] !== undefined) {
var row = this._rows[old_id];
delete this._rows[old_id];
row.setAttribute('zid', new_id);
row.setAttribute('id', this.table_name + new_id);
$(row).removeClass('local');
this._rows[new_id] = row;
}
}
};
}());
if (typeof module !== 'undefined') {
module.exports = MessageListView;
}