index.js

'use strict';

const _		= {
	defaultsDeep: require('lodash.defaultsdeep'),
	isEmpty			: require('lodash.isempty'),
};

// -----------------------------------------------------------------------------

const LIB	= require('./lib');
const UTIL	= require('./lib/UTIL');

// -----------------------------------------------------------------------------

const {
	name		: PLUGIN_NAME,
	homepage: HOMEPAGE,
} = require('./package.json');

/**
 * holds relevant functions and data
 */
const PLUGIN = {
	name							: PLUGIN_NAME,
	homepage					: HOMEPAGE,
	key								: PLUGIN_NAME.replace('vuepress-plugin-', ''), // used in frontmatter
	allowed_feed_types: ['rss2', 'atom1', 'json1'],
	pages							: [],
	options						: {},
};

// -----------------------------------------------------------------------------

/**
 * @return {object}
 */
PLUGIN.get_options_defaults = ( context ) =>
{

	const {
		title,
		description
	} = context.getSiteData ? context.getSiteData() : context;

	// ---------------------------------------------------------------------------

	// Feed class options
	// @see: https://github.com/jpmonette/feed#example

	const feed_options = {

		title,
		description,
		generator: PLUGIN.homepage,

		// -------------------------------------------------------------------------

		// the following are auto populated in PLUGIN.get_options()
		// if they are not set as options
		/*
		id,
		link,
		feedLinks,
		*/

		// -------------------------------------------------------------------------

		// ref:
		/*
		title: "Feed Title",
		description: "This is my personal feed!",
		id: "http://example.com/",
		link: "http://example.com/",
		image: "http://example.com/image.png",
		favicon: "http://example.com/favicon.ico",
		copyright: "All rights reserved 2013, John Doe",
		updated: new Date(2013, 6, 14), // optional, default = today
		generator: "awesome", // optional, default = 'Feed for Node.js'
		feedLinks: {
			json: "https://example.com/json",
			atom: "https://example.com/atom"
		},
		author: {
			name: "John Doe",
			email: "johndoe@example.com",
			link: "https://example.com/johndoe"
		}
		*/

	};

	// ---------------------------------------------------------------------------

	const out = {

		// required; it can also be used as enable/disable

		canonical_base: '',

		// -------------------------------------------------------------------------

		// Feed class options

		feed_options,

		// -------------------------------------------------------------------------

		// @notes:
		// property name is also the name of the FEED package function

		feeds: {

			rss2: {
				enable		: true,
				file_name	: 'rss.xml',
				head_link	: {
					enable: true,
					type	: 'application/rss+xml',
					title	: '%%site_title%% RSS Feed',
				}
			},

			// -----------------------------------------------------------------------

			atom1: {
				enable		: true,
				file_name	: 'feed.atom',
				head_link	: {
					enable: true,
					type	: 'application/atom+xml',
					title	: '%%site_title%% Atom Feed',
				}
			},

			// -----------------------------------------------------------------------

			json1: {
				enable		: true,
				file_name	: 'feed.json',
				head_link	: {
					enable: true,
					type	: 'application/json',
					title	: '%%site_title%% JSON Feed',
				}
			},

		},

		// -------------------------------------------------------------------------

		// order of what gets the highest priority:
		//
		// 1. frontmatter
		// 2. page excerpt
		// 3. content markdown paragraph
		// 4. content regular html <p>

		description_sources: [

			'frontmatter',
			'excerpt',

			// markdown paragraph regex
			// @todo: needs work
			//
			/^((?:(?!^#)(?!^\-|\+)(?!^[0-9]+\.)(?!^!\[.*?\]\((.*?)\))(?!^\[\[.*?\]\])(?!^\{\{.*?\}\})[^\n]|\n(?! *\n))+)(?:\n *)+\n/gim,
			//
			// this excludes blockquotes using `(?!^>)`
			///^((?:(?!^#)(?!^\-|\+)(?!^[0-9]+\.)(?!^!\[.*?\]\((.*?)\))(?!^>)(?!^\[\[.*?\]\])(?!^\{\{.*?\}\})[^\n]|\n(?! *\n))+)(?:\n *)+\n/gim,

			// html paragraph regex
			/<p(?:.*?)>(.*?)<\/p>/i,

			// -----------------------------------------------------------------------

			// @notes: setting as array require escaping `\`

			//['^((?:(?!^#)(?!^\-|\+)(?!^[0-9]+\.)(?!^\[\[.*?\]\])(?!^\{\{.*?\}\})[^\n]|\n(?! *\n))+)(?:\n *)+\n', 'gim'],
			//['<p(?:.*?)>(.*?)<\/p>', 'i'],

		],

		// -------------------------------------------------------------------------

		// @consider description max words/char

		// -------------------------------------------------------------------------

		// order of what gets the highest priority:
		//
		// 1. frontmatter
		// 2. content markdown image such as `![alt text](http://url)`
		// 3. content regular html img

		image_sources: [

			'frontmatter',

			/!\[.*?\]\((.*?)\)/i,					// markdown image regex
			/<img.*?src=['"](.*?)['"]/i,	// html image regex

			// -----------------------------------------------------------------------

			// @notes: setting as array require escaping `\`

			//['!\[.*?\]\((.*?)\)', 'i'],
			//['<img.*?src=[\'"](.*?)[\'"]', 'i'],

		],

		// -------------------------------------------------------------------------

		// pages in current directories will be auto added as feed
		// unless they are disabled using their frontmatter
		// this option is used by the default is_feed_page function

		posts_directories: ['/blog/', '/_posts/'],

		// -------------------------------------------------------------------------

		// function to check if the page is to be used in a feed item

		is_feed_page: PLUGIN.is_feed_page, // function

		// -------------------------------------------------------------------------

		count: 20,

		// optional sorting function for the entries.
		// Gets the array entries as the input, expects the sorted array
		// as its output.
		// e.g.:	 sort:	entries => _.reverse( _.sortBy( entries, 'date' ) ),
		sort: entries => entries,	// defaults to just returning it as it is

		// -------------------------------------------------------------------------

		// supported - use in config as needed

		// category
		// contributor

	};

	// ---------------------------------------------------------------------------

	return out;

};
// PLUGIN.get_options_defaults()



/**
 * @return {object}
 */
PLUGIN.get_options = ( plugin_options, context ) =>
{

	if ( _.isEmpty( PLUGIN.options ) )
	{
		PLUGIN.options = _.defaultsDeep(
			plugin_options,
			PLUGIN.get_options_defaults( context )
		);

		// -------------------------------------------------------------------------

		// default link and id

		if ( ! PLUGIN.options.feed_options.hasOwnProperty('link') )
		{
			PLUGIN.options.feed_options.link = plugin_options.canonical_base;
		}

		if ( ! PLUGIN.options.feed_options.hasOwnProperty('id') )
		{
			PLUGIN.options.feed_options.id = plugin_options.canonical_base;
		}

		// -------------------------------------------------------------------------

		// default feedLinks

		if ( 		! PLUGIN.options.feed_options.hasOwnProperty('feedLinks')
				 && ! _.isEmpty( PLUGIN.options.feeds ) )
		{
			PLUGIN.options.feed_options.feedLinks = {};

			const feeds = PLUGIN.options.feeds || {};

			for ( let key of Object.keys( feeds ) )
			{
				if ( ! PLUGIN.allowed_feed_types.includes( key ) )
				{
					continue;
				}

				// ---------------------------------------------------------------------

				const url = PLUGIN.get_feed_url( feeds[ key ] );

				if ( ! url )
				{
					continue;
				}

				// ---------------------------------------------------------------------

				key = key.replace(/[0-9]/g, ''); // remove numbers from key;

				PLUGIN.options.feed_options.feedLinks[ key ] = url;
			}
		}

		// -------------------------------------------------------------------------

		// internal - used in other files/classes

		PLUGIN.options._internal = {
			name							: PLUGIN.name,
			homepage					: PLUGIN.homepage,
			key								: PLUGIN.key,
			allowed_feed_types: PLUGIN.allowed_feed_types,
		};

	}

	// ---------------------------------------------------------------------------

	return PLUGIN.options;

};
// PLUGIN.get_options()



/**
 * @return {bool}
 */
PLUGIN.good_to_go = ( plugin_options, context ) =>
{

	const options = PLUGIN.get_options( plugin_options, context );

	// ---------------------------------------------------------------------------

	return ( 		options.canonical_base
					 && ! _.isEmpty( options.feeds )
					 && ! _.isEmpty( PLUGIN.pages ) );

};
// PLUGIN.good_to_go()



/**
 * @return {string}
 */
PLUGIN.get_feed_url = feed =>
{

	if ( feed.enable && feed.file_name )
	{
		return UTIL.resolve_url(PLUGIN.options.canonical_base, feed.file_name);
	}

};
// PLUGIN.get_feed_url()



/**
 * @return {bool}
 */
PLUGIN.get_page_feed_settings = frontmatter => frontmatter.feed || {};



/**
 * @return {bool}
 */
PLUGIN.get_page_type = frontmatter => frontmatter.type || '';



/**
 * @return {bool}
 */
PLUGIN.is_page_type_post = frontmatter => ( 'post' === PLUGIN.get_page_type( frontmatter ).toLowerCase() );



/**
 * @return {bool}
 */
PLUGIN.is_feed_page = ( page ) =>
{

	const { frontmatter, path } = page;

	// ---------------------------------------------------------------------------

	if ( ! _.isEmpty( frontmatter ) )
	{
		// use `frontmatter.feed.enable` to exclude a particular page/post
		// bailout if it is set to false

		const page_feed_settings = PLUGIN.get_page_feed_settings( frontmatter );

		/*
		if ( 		page_feed_settings.hasOwnProperty('enable')
				 && ! page_feed_settings.enable )
		{
			return false;
		}
		*/

		// @notes:
		// as opposed to the above way of bailing out if set to false
		// the following means that any page that has `frontmatter.feed.enable`
		// set to true will be added

		if ( page_feed_settings.hasOwnProperty('enable') )
		{
			return ( page_feed_settings.enable );
		}

		// -------------------------------------------------------------------------

		if ( PLUGIN.is_page_type_post( frontmatter ) )
		{
			return true;
		}
	}

	// ---------------------------------------------------------------------------

	const directories = PLUGIN.options.posts_directories || [];

	if ( ! _.isEmpty( directories ) )
	{
		for ( const dir of directories )
		{
			if ( path.startsWith(`${dir}`) )
			{
				return true;
			}
		}
	}

	// ---------------------------------------------------------------------------

	return false;

};
// PLUGIN.is_feed_page()

// -----------------------------------------------------------------------------

module.exports = ( plugin_options, context ) => ({

	/**
	 * used for collecting pages that would be used in feed;
	 * the reason i'm using this, is that `getSiteData` only gets `page.toJson()`,
	 * which only assigns preperties that don't start with '_'
	 * and what i need is the $page._strippedContent to get content for the feed
	 */
	extendPageData ( $page ) {

		try {

			if ( PLUGIN.get_options( plugin_options, context ).is_feed_page( $page ) )
			{
				PLUGIN.pages.push( $page );
			}

		} catch ( err ) {

			LIB.LOG.error( err.message );

		}

	},

	// ---------------------------------------------------------------------------

	/**
	 * used for adding head links
	 */
	async ready() {

		try {

			if ( PLUGIN.good_to_go( plugin_options, context ) )
			{
				await new LIB.Head( PLUGIN.options, context ).add_links();
			}

		} catch ( err ) {

			LIB.LOG.error( err.message );

		}

	},

	// ---------------------------------------------------------------------------

	/**
	 * used for generating the feed files
	 */
	async generated ( pagePaths ) {

		try {

			if ( PLUGIN.good_to_go( plugin_options, context ) )
			{
				await new LIB.Generator( PLUGIN.pages, PLUGIN.options, context ).generate();
			}

		} catch ( err ) {

			LIB.LOG.error( err.message );

		}

	}

});