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shrine-medco/shrine-webclient/src/main/html/node_modules/node-watch/lib/watch.js
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watch.js
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			/**
			* Module dependencies.
			*/
			var fs = require('fs')
			, path = require('path');


			/**
			* Utility functions to synchronously test whether the giving path
			* is a file or a directory or a symbolic link.
			*/
			var is = function(ret) {
			var shortcuts = {
			'file': 'File'
			, 'dir': 'Directory'
			, 'sym': 'SymbolicLink'
			};
			Object.keys(shortcuts).forEach(function(method) {
			var stat = fs[method === 'sym' ? 'lstatSync' :'statSync'];
			ret[method] = function(fpath) {
			try {
			var yes = stat(fpath)['is' + shortcuts[method]]();
			memo.push(fpath, method);
			return yes;
			} catch(e) {}
			}
			});
			return ret;
			}({});


			/**
			* Get sub-directories in a directory.
			*/
			var sub = function(parent, cb) {
			if (is.dir(parent)) {
			fs.readdir(parent, function(err, all) {
			all && all.forEach(function(f) {
			var sdir = path.join(parent, f)
			if (is.dir(sdir)) {
			cb.call(null, sdir)
			}
			});
			});
			}
			};


			/**
			* Mixing object properties.
			*/
			var mixin = function() {
			var mix = {};
			[].forEach.call(arguments, function(arg) {
			for (var name in arg) {
			if (arg.hasOwnProperty(name)) {
			mix[name] = arg[name];
			}
			}
			});
			return mix;
			};


			/**
			* A container for memorizing names of files or directories.
			*/
			var memo = function(memo) {
			return {
			push: function(name, type) {
			memo[name] = type;
			},
			has: function(name) {
			return {}.hasOwnProperty.call(memo, name);
			},
			update: function(name) {
			if (!is.file(name) \|\| !is.dir(name)) {
			delete memo[name];
			}
			return true;
			}
			};
			}({});


			/**
			* A Container for storing unique and valid filenames.
			*/
			var fileNameCache = function(cache) {
			return {
			push: function(name) {
			cache[name] = 1;
			return this;
			},
			each: function() {
			var temp = Object.keys(cache).filter(function(name){
			return is.file(name) \|\| memo.has(name) && memo.update(name);
			});
			temp.forEach.apply(temp, arguments);
			return this;
			},
			clear: function(){
			cache = {};
			return this;
			}
			};
			}({});


			/**
			* Abstracting the way of avoiding duplicate function call.
			*/
			var worker = function() {
			var free = true;
			return {
			busydoing: function(cb) {
			if (free) {
			free = false;
			cb.call();
			}
			},
			free: function() {
			free = true;
			}
			}
			}();


			/**
			* Delay function call and ignore invalid filenames.
			*/
			var normalizeCall = function(fname, options, cb) {
			// Store each name of the modifying or temporary files generated by an editor.
			fileNameCache.push(fname);

			worker.busydoing(function() {
			// A heuristic delay of the write-to-file process.
			setTimeout(function() {

			// When the write-to-file process is done, send all filtered filenames
			// to the callback function and call it.
			fileNameCache
			.each(function(f) {
			// Watch new created directory.
			if (options.recursive && !memo.has(f) && is.dir(f)) {
			watch(f, options, cb);
			}
			cb.call(null, f);
			}).clear();

			worker.free();

			}, 100);
			});
			};


			/**
			* Catch exception on Windows when deleting a directory.
			*/
			var catchException = function() {};


			/**
			* Option handler for the `watch` function.
			*/
			var handleOptions = function(origin, defaultOptions) {
			return function() {
			var args = [].slice.call(arguments);
			if (Object.prototype.toString.call(args[1]) === '[object Function]') {
			args[2] = args[1];
			}
			if (!Array.isArray(args[0])) {
			args[0] = [args[0]];
			}
			//overwrite default options
			args[1] = mixin(defaultOptions, args[1]);
			//handle multiple files.
			args[0].forEach(function(path) {
			origin.apply(null, [path].concat(args.slice(1)));
			});
			}
			};


			/**
			* Watch a file or a directory (recursively by default).
			*
			* @param {String} fpath
			* @options {Object} options
			* @param {Function} cb
			*
			* Options:
			* `recursive`: Watch it recursively or not (defaults to true).
			* `followSymLinks`: Follow symbolic links or not (defaults to false).
			* `maxSymLevel`: The max number of following symbolic links (defaults to 1).
			*
			* Example:
			*
			* watch('fpath', {recursive: true}, function(file) {
			* console.log(file, ' changed');
			* });
			*/
			function watch(fpath, options, cb) {
			if (is.sym(fpath)
			&& !(options.followSymLinks
			&& options.maxSymLevel--)) {
			return;
			}
			// Due to the unstable fs.watch(), if the `fpath` is a file then
			// switch to watch its parent directory instead of watch it directly.
			// Once the logged filename matches it then triggers the callback function.
			if (is.file(fpath)) {
			var parent = path.resolve(fpath, '..');
			fs.watch(parent, options, function(evt, fname) {
			if (path.basename(fpath) === fname) {
			normalizeCall(fpath, options, cb);
			}
			}).on('error', catchException);
			} else if (is.dir(fpath)) {
			fs.watch(fpath, options, function(evt, fname) {
			if (fname) {
			normalizeCall(path.join(fpath, fname), options, cb);
			}
			}).on('error', catchException);

			if (options.recursive) {
			// Recursively watch its sub-directories.
			sub(fpath, function(dir) {
			watch(dir, options, cb);
			});
			}
			}
			};


			/**
			* Set default options and expose.
			*/
			module.exports = handleOptions(watch, {
			recursive: true
			, followSymLinks: false
			, maxSymLevel: 1
			});