cache-storage/src/Storage/Sync/Storage.coffee

[ABANDONED] Advanced cache storage for node js

isWindow = if typeof window == 'undefined' then false else true

if !isWindow
	path = require 'path'

BaseStorage = require '../Storage'
moment = require 'moment'
Cache = require '../../Cache'

class Storage extends BaseStorage


	async: false


	read: (key) ->
		data = @getData()
		if typeof data[key] == 'undefined'
			return null
		else
			if @verify(@findMeta(key))
				return data[key]
			else
				@remove(key)
				return null


	write: (key, data, dependencies = {}) ->
		all = @getData()
		all[key] = data
		meta = @getMeta()
		meta[key] = dependencies
		@writeData(all, meta)


	remove: (key) ->
		data = @getData()
		meta = @getMeta()
		if typeof data[key] != 'undefined'
			delete data[key]
			delete meta[key]
		@writeData(data, meta)


	removeAll: ->
		@writeData({}, {})


	clean: (conditions) ->
		typeFn = Object.prototype.toString
		type = typeFn.call(conditions)
		if conditions == Cache.ALL
			@removeAll()

		else if type == '[object Object]'
			if typeof conditions[Cache.TAGS] != 'undefined'
				if typeFn(conditions[Cache.TAGS]) == '[object String]' then conditions[Cache.TAGS] = [conditions[Cache.TAGS]]
				for tag in conditions[Cache.TAGS]
					for key in @findKeysByTag(tag)
						@remove(key)

			if typeof conditions[Cache.PRIORITY] != 'undefined'
				for key in @findKeysByPriority(conditions[Cache.PRIORITY])
					@remove(key)


	findMeta: (key) ->
		meta = @getMeta()
		return if typeof meta[key] != 'undefined' then meta[key] else null


	findKeysByTag: (tag) ->
		metas = @getMeta()
		result = []
		for key, meta of metas
			if typeof meta[Cache.TAGS] != 'undefined' && meta[Cache.TAGS].indexOf(tag) != -1
				result.push(key)
		return result


	findKeysByPriority: (priority) ->
		metas = @getMeta()
		result = []
		for key, meta of metas
			if typeof meta[Cache.PRIORITY] != 'undefined' && meta[Cache.PRIORITY] <= priority
				result.push(key)
		return result


	verify: (meta) ->
		typefn = Object.prototype.toString

		if typefn.call(meta) == '[object Object]'
			if typeof meta[Cache.EXPIRE] != 'undefined'
				if moment().valueOf() >= meta[Cache.EXPIRE]
					return false

			if typeof meta[Cache.ITEMS] != 'undefined'
				for item in meta[Cache.ITEMS]
					item = @findMeta(item)
					if (item == null) || (item != null && @verify(item) == false)
						return false

			if typeof meta[Cache.FILES] != 'undefined'
				@checkFilesSupport()
				if isWindow
					for file, time of meta[Cache.FILES]
						mtime = window.require.getStats(file).mtime
						if mtime == null
							throw new Error 'File stats are disabled in your simq configuration. Can not get stats for ' + file + '.'

						if window.require.getStats(file).mtime.getTime() != time
							return false
				else
					for file, time of meta[Cache.FILES]
						if (new Date(Cache.getFs().statSync(file).mtime)).getTime() != time
							return false

		return true


	parseDependencies: (dependencies) ->
		typefn = Object.prototype.toString
		result = {}

		if typefn.call(dependencies) == '[object Object]'
			if typeof dependencies[Cache.PRIORITY] != 'undefined'
				result[Cache.PRIORITY] = dependencies[Cache.PRIORITY]

			if typeof dependencies[Cache.TAGS] != 'undefined'
				result[Cache.TAGS] = dependencies[Cache.TAGS]

			if typeof dependencies[Cache.ITEMS] != 'undefined'
				result[Cache.ITEMS] = []
				for item in dependencies[Cache.ITEMS]
					result[Cache.ITEMS].push(@cache.generateKey(item))

			if typeof dependencies[Cache.EXPIRE] != 'undefined'
				switch typefn.call(dependencies[Cache.EXPIRE])
					when '[object String]'
						time = moment(dependencies[Cache.EXPIRE], Cache.TIME_FORMAT)

					when '[object Object]'
						time = moment().add(dependencies[Cache.EXPIRE])

					else
						throw new Error 'Expire format is not valid'

				result[Cache.EXPIRE] = time.valueOf()

			if typeof dependencies[Cache.FILES] != 'undefined'
				@checkFilesSupport()
				files = {}
				if isWindow
					for file in dependencies[Cache.FILES]
						mtime = window.require.getStats(file).mtime
						if mtime == null
							throw new Error 'File stats are disabled in your simq configuration. Can not get stats for ' + file + '.'

						file = window.require.resolve(file)
						files[file] = mtime.getTime()
				else
					for file in dependencies[Cache.FILES]
						file = path.resolve(file)
						files[file] = (new Date(Cache.getFs().statSync(file).mtime)).getTime()

				result[Cache.FILES] = files

		return result


module.exports = Storage