'use strict';

var winston = require('winston');
var fork = require('child_process').fork;
var path = require('path');
var async = require('async');
var nconf = require('nconf');
var fs = require('fs');
var plugins = require('../plugins');
var utils = require('../../public/src/utils');

module.exports = function (Meta) {

	Meta.js = {
		target: {},
		scripts: {
			base: [
				'./node_modules/jquery/dist/jquery.js',
				'./node_modules/socket.io-client/dist/socket.io.js',
				'public/vendor/jquery/timeago/jquery.timeago.js',
				'public/vendor/jquery/js/jquery.form.min.js',
				'public/vendor/visibility/visibility.min.js',
				'public/vendor/bootstrap/js/bootstrap.js',
				'public/vendor/jquery/bootstrap-tagsinput/bootstrap-tagsinput.min.js',
				'public/vendor/jquery/textcomplete/jquery.textcomplete.js',
				'public/vendor/requirejs/require.js',
				'public/src/require-config.js',
				'public/vendor/bootbox/bootbox.min.js',
				'public/vendor/tinycon/tinycon.js',
				'public/vendor/xregexp/xregexp.js',
				'public/vendor/xregexp/unicode/unicode-base.js',
				'./node_modules/templates.js/lib/templates.js',
				'public/src/utils.js',
				'public/src/sockets.js',
				'public/src/app.js',
				'public/src/ajaxify.js',
				'public/src/overrides.js',
				'public/src/widgets.js',
				"./node_modules/promise-polyfill/promise.js"
			],

			// files listed below are only available client-side, or are bundled in to reduce # of network requests on cold load
			rjs: [
				'public/src/client/footer.js',
				'public/src/client/chats.js',
				'public/src/client/infinitescroll.js',
				'public/src/client/pagination.js',
				'public/src/client/recent.js',
				'public/src/client/unread.js',
				'public/src/client/topic.js',
				'public/src/client/topic/events.js',
				'public/src/client/topic/flag.js',
				'public/src/client/topic/fork.js',
				'public/src/client/topic/move.js',
				'public/src/client/topic/posts.js',
				'public/src/client/topic/postTools.js',
				'public/src/client/topic/threadTools.js',
				'public/src/client/categories.js',
				'public/src/client/category.js',
				'public/src/client/categoryTools.js',

				'public/src/modules/translator.js',
				'public/src/modules/notifications.js',
				'public/src/modules/chat.js',
				'public/src/modules/components.js',
				'public/src/modules/sort.js',
				'public/src/modules/navigator.js',
				'public/src/modules/topicSelect.js',
				'public/src/modules/share.js',
				'public/src/modules/search.js',
				'public/src/modules/alerts.js',
				'public/src/modules/taskbar.js',
				'public/src/modules/helpers.js',
				'public/src/modules/sounds.js',
				'public/src/modules/string.js'
			],

			// modules listed below are routed through express (/src/modules) so they can be defined anonymously
			modules: {
				"Chart.js": './node_modules/chart.js/dist/Chart.min.js',
				"mousetrap.js": './node_modules/mousetrap/mousetrap.min.js',
				"jqueryui.js": 'public/vendor/jquery/js/jquery-ui.js',
				"buzz.js": 'public/vendor/buzz/buzz.js'
			}
		}
	};

	Meta.js.bridgeModules = function (app, callback) {
		// Add routes for AMD-type modules to serve those files
		function addRoute(relPath) {
			var relativePath = nconf.get('relative_path');

			app.get(relativePath + '/src/modules/' + relPath, function (req, res) {
				return res.sendFile(path.join(__dirname, '../../', Meta.js.scripts.modules[relPath]), {
					maxAge: app.enabled('cache') ? 5184000000 : 0
				});
			});
		}

		var numBridged = 0;

		for(var relPath in Meta.js.scripts.modules) {
			if (Meta.js.scripts.modules.hasOwnProperty(relPath)) {
				addRoute(relPath);
				++numBridged;
			}
		}

		winston.verbose('[meta/js] ' + numBridged + ' of ' + Object.keys(Meta.js.scripts.modules).length + ' modules bridged');
		callback();
	};

	Meta.js.minify = function (target, callback) {
		winston.verbose('[meta/js] Minifying ' + target);

		var forkProcessParams = setupDebugging();
		var minifier = Meta.js.minifierProc = fork('minifier.js', [], forkProcessParams);

		Meta.js.target[target] = {};

		Meta.js.prepare(target, function (err) {
			if (err) {
				return callback(err);
			}
			minifier.send({
				action: 'js',
				minify: global.env !== 'development',
				scripts: Meta.js.target[target].scripts
			});
		});

		minifier.on('message', function (message) {
			switch(message.type) {
			case 'end':
				Meta.js.target[target].cache = message.minified;
				Meta.js.target[target].map = message.sourceMap;
				winston.verbose('[meta/js] ' + target + ' minification complete');
				minifier.kill();

				if (nconf.get('local-assets') === undefined || nconf.get('local-assets') !== false) {
					return Meta.js.commitToFile(target, callback);
				} else {
					return callback();
				}

				break;
			case 'error':
				winston.error('[meta/js] Could not compile ' + target + ': ' + message.message);
				minifier.kill();

				callback(new Error(message.message));
				break;
			}
		});
	};

	Meta.js.prepare = function (target, callback) {
		var pluginsScripts = [];

		var pluginDirectories = [];

		pluginsScripts = plugins[target === 'nodebb.min.js' ? 'clientScripts' : 'acpScripts'].filter(function (path) {
			if (path.endsWith('.js')) {
				return true;
			}

			pluginDirectories.push(path);
			return false;
		});

		async.each(pluginDirectories, function (directory, next) {
			utils.walk(directory, function (err, scripts) {
				pluginsScripts = pluginsScripts.concat(scripts);
				next(err);
			});
		}, function (err) {
			if (err) {
				return callback(err);
			}

			var basePath = path.resolve(__dirname, '../..');

			Meta.js.target[target].scripts = Meta.js.scripts.base.concat(pluginsScripts);

			if (target === 'nodebb.min.js') {
				Meta.js.target[target].scripts = Meta.js.target[target].scripts.concat(Meta.js.scripts.rjs);
			}

			Meta.js.target[target].scripts = Meta.js.target[target].scripts.map(function (script) {
				return path.relative(basePath, script).replace(/\\/g, '/');
			});

			callback();
		});
	};

	Meta.js.killMinifier = function () {
		if (Meta.js.minifierProc) {
			Meta.js.minifierProc.kill('SIGTERM');
		}
	};

	Meta.js.commitToFile = function (target, callback) {
		fs.writeFile(path.join(__dirname, '../../public/' + target), Meta.js.target[target].cache, function (err) {
			callback(err);
		});
	};

	Meta.js.getFromFile = function (target, callback) {
		function readFile(filePath, next) {
			fs.readFile(filePath, function (err, contents) {
				if (err) {
					if (err.code === 'ENOENT') {
						if (!filePath.endsWith('.map')) {
							winston.warn('[meta/js] ' + filePath + ' not found on disk, did you run ./nodebb build?');
						}
						return next(null, '');
					}
				}
				next(err, contents);
			});
		}

		var scriptPath = path.join(nconf.get('base_dir'), 'public/' + target);
		var mapPath = path.join(nconf.get('base_dir'), 'public/' + target + '.map');

		async.parallel({
			script: function (next) {
				readFile(scriptPath, next);
			},
			map: function (next) {
				readFile(mapPath, next);
			}
		}, function (err, results) {
			if (err) {
				return callback(err);
			}
			Meta.js.target[target] = {
				cache: results.script,
				map: results.map
			};
			callback();
		});
	};

	function setupDebugging() {
		/**
		 * Check if the parent process is running with the debug option --debug (or --debug-brk)
		 */
		var forkProcessParams = {};
		if(global.v8debug || parseInt(process.execArgv.indexOf('--debug'), 10) !== -1) {
			/**
			 * use the line below if you want to debug minifier.js script too (or even --debug-brk option, but
			 * you'll have to setup your debugger and connect to the forked process)
			 */
			//forkProcessParams = {execArgv: ['--debug=' + (global.process.debugPort + 1), '--nolazy']};

			/**
			 * otherwise, just clean up --debug/--debug-brk options which are set up by default from the parent one
			 */
			forkProcessParams = {execArgv: []};
		}

		return forkProcessParams;
	}
};