gitlab-org--gitlab-foss/app/assets/javascripts/behaviors/preview_markdown.js

209 lines
5.5 KiB
JavaScript

/* eslint-disable func-names */
import $ from 'jquery';
import axios from '~/lib/utils/axios_utils';
import flash from '~/flash';
import { __ } from '~/locale';
// MarkdownPreview
//
// Handles toggling the "Write" and "Preview" tab clicks, rendering the preview
// (including the explanation of quick actions), and showing a warning when
// more than `x` users are referenced.
//
let lastTextareaHeight;
let lastTextareaPreviewed;
function MarkdownPreview() {}
// Minimum number of users referenced before triggering a warning
MarkdownPreview.prototype.referenceThreshold = 10;
MarkdownPreview.prototype.emptyMessage = __('Nothing to preview.');
MarkdownPreview.prototype.ajaxCache = {};
MarkdownPreview.prototype.showPreview = function($form) {
const preview = $form.find('.js-md-preview');
const url = preview.data('url');
if (preview.hasClass('md-preview-loading')) {
return;
}
const mdText = $form.find('textarea.markdown-area').val();
if (mdText === undefined) {
return;
}
if (mdText.trim().length === 0) {
preview.text(this.emptyMessage);
this.hideReferencedUsers($form);
} else {
preview.addClass('md-preview-loading').text(__('Loading...'));
this.fetchMarkdownPreview(mdText, url, response => {
let body;
if (response.body.length > 0) {
({ body } = response);
} else {
body = this.emptyMessage;
}
preview.removeClass('md-preview-loading').html(body);
preview.renderGFM();
this.renderReferencedUsers(response.references.users, $form);
if (response.references.commands) {
this.renderReferencedCommands(response.references.commands, $form);
}
});
}
};
MarkdownPreview.prototype.fetchMarkdownPreview = function(text, url, success) {
if (!url) {
return;
}
if (text === this.ajaxCache.text) {
success(this.ajaxCache.response);
return;
}
axios
.post(url, {
text,
})
.then(({ data }) => {
this.ajaxCache = {
text,
response: data,
};
success(data);
})
.catch(() => flash(__('An error occurred while fetching markdown preview')));
};
MarkdownPreview.prototype.hideReferencedUsers = function($form) {
$form.find('.referenced-users').hide();
};
MarkdownPreview.prototype.renderReferencedUsers = function(users, $form) {
const referencedUsers = $form.find('.referenced-users');
if (referencedUsers.length) {
if (users.length >= this.referenceThreshold) {
referencedUsers.show();
referencedUsers.find('.js-referenced-users-count').text(users.length);
} else {
referencedUsers.hide();
}
}
};
MarkdownPreview.prototype.hideReferencedCommands = function($form) {
$form.find('.referenced-commands').hide();
};
MarkdownPreview.prototype.renderReferencedCommands = function(commands, $form) {
const referencedCommands = $form.find('.referenced-commands');
if (commands.length > 0) {
referencedCommands.html(commands);
referencedCommands.show();
} else {
referencedCommands.html('');
referencedCommands.hide();
}
};
const markdownPreview = new MarkdownPreview();
const previewButtonSelector = '.js-md-preview-button';
const writeButtonSelector = '.js-md-write-button';
lastTextareaPreviewed = null;
const markdownToolbar = $('.md-header-toolbar');
$.fn.setupMarkdownPreview = function() {
const $form = $(this);
$form.find('textarea.markdown-area').on('input', () => {
markdownPreview.hideReferencedUsers($form);
});
};
$(document).on('markdown-preview:show', (e, $form) => {
if (!$form) {
return;
}
lastTextareaPreviewed = $form.find('textarea.markdown-area');
lastTextareaHeight = lastTextareaPreviewed.height();
// toggle tabs
$form
.find(writeButtonSelector)
.parent()
.removeClass('active');
$form
.find(previewButtonSelector)
.parent()
.addClass('active');
// toggle content
$form.find('.md-write-holder').hide();
$form.find('.md-preview-holder').show();
markdownToolbar.removeClass('active');
markdownPreview.showPreview($form);
});
$(document).on('markdown-preview:hide', (e, $form) => {
if (!$form) {
return;
}
lastTextareaPreviewed = null;
if (lastTextareaHeight) {
$form.find('textarea.markdown-area').height(lastTextareaHeight);
}
// toggle tabs
$form
.find(writeButtonSelector)
.parent()
.addClass('active');
$form
.find(previewButtonSelector)
.parent()
.removeClass('active');
// toggle content
$form.find('.md-write-holder').show();
$form.find('textarea.markdown-area').focus();
$form.find('.md-preview-holder').hide();
markdownToolbar.addClass('active');
markdownPreview.hideReferencedCommands($form);
});
$(document).on('markdown-preview:toggle', (e, keyboardEvent) => {
let $target;
$target = $(keyboardEvent.target);
if ($target.is('textarea.markdown-area')) {
$(document).triggerHandler('markdown-preview:show', [$target.closest('form')]);
keyboardEvent.preventDefault();
} else if (lastTextareaPreviewed) {
$target = lastTextareaPreviewed;
$(document).triggerHandler('markdown-preview:hide', [$target.closest('form')]);
keyboardEvent.preventDefault();
}
});
$(document).on('click', previewButtonSelector, function(e) {
e.preventDefault();
const $form = $(this).closest('form');
$(document).triggerHandler('markdown-preview:show', [$form]);
});
$(document).on('click', writeButtonSelector, function(e) {
e.preventDefault();
const $form = $(this).closest('form');
$(document).triggerHandler('markdown-preview:hide', [$form]);
});
export default MarkdownPreview;