base-domain/src/util.coffee

simple module to help build Domain-Driven Design

'use strict'

deepEqual = require 'deep-eql'
clone     = require 'clone'

###*
@method Util
###
class Util

    ###*
    get __proto__ of the given object

    @method getProto
    @static
    @param {Object} obj
    @return {Object} __proto__
    ###
    @getProto: (obj) ->
        if Object.getPrototypeOf?
            return Object.getPrototypeOf(obj)
        else
            obj.__proto__

    ###*
    converts hyphenation to camel case

        'shinout-no-macbook-pro' => 'ShinoutNoMacbookPro'
        'shinout-no-macbook-pro' => 'shinoutNoMacbookPro' # if lowerFirst = true

    @method camelize
    @static
    @param {String} hyphened
    @param {Boolean} [lowerFirst=false] make capital char lower
    @return {String} cameled
    ###
    @camelize: (hyphened, lowerFirst = false) ->
       (for substr, i in hyphened.split('-')
           if i is 0 and lowerFirst
               substr
           else
               substr.charAt(0).toUpperCase() + substr.slice(1)
       ).join('')


    ###*
    converts hyphenation to camel case

        'ShinoutNoMacbookPro' => 'shinout-no-macbook-pro'
        'ABC' => 'a-b-c' # current implementation... FIXME ?

    @method hyphenize
    @static
    @param {String} hyphened
    @return {String} cameled
    ###
    @hyphenize: (cameled) ->

        cameled = cameled.charAt(0).toUpperCase() + cameled.slice(1)
        cameled.replace(/([A-Z])/g, (st)-> '-' + st.charAt(0).toLowerCase()).slice(1)


    @serialize: (v) ->

        JSON.stringify do attachClassName = (val = v, inModel = false) ->

            return val if not val? or typeof val isnt 'object'

            if Array.isArray val
                return (attachClassName(item, inModel) for item in val)

            ret = {}
            isModel = val.constructor.className?
            Object.keys(val).forEach (key) ->
                ret[key] = attachClassName(val[key], isModel || inModel)

            if val instanceof Error
                ret.stack = val.stack
                ret.__errorMessage__ = val.message

            else if isModel and not inModel
                ret.__className__ = val.constructor.className

            return ret


    @deserialize: (str, facade) ->

        return str if not str?

        do restore = (val = JSON.parse str) ->

            return val if not val? or typeof val isnt 'object'

            if Array.isArray val
                return (restore(item) for item in val)

            if val.__errorMessage__
                ret = new Error(val.__errorMessage__)
                ret[key] = value for key, value of val
                delete ret.__errorMessage__
                return ret

            else if val.__className__
                className = val.__className__
                delete val.__className__
                return facade.createModel(className, val)
            else
                ret = {}
                ret[key] = restore(value) for key, value of val
                return ret



    ###*
    requires js file
    in Titanium, file-not-found-like-exception occurred in require function cannot be caught.
    Thus, before require function is called, check the existence of the file.
    Only in iOS this check occurs.
    File extension must be '.js' in Titanium.

    @method requireFile
    @static
    @param {String} file name without extension
    @return {any} required value
    ###
    @requireFile: (file) ->
        if not Ti?
            return require file

        # in Titanium
        path = file + '.js'

        if Ti.Platform.name is 'android'
            return require file

        fileInfo = Ti.Filesystem.getFile(Ti.Filesystem.resourcesDirectory, path)

        if fileInfo.exists()
            return require file
        else
            throw new Error("#{path}: no such file.")



    ###*
    Parse a file as JSON format.
    In Titanium, requiring JSON does not work.

    @method requireJSON
    @static
    @param {String} path
    @return {any} required value
    ###
    @requireJSON: (path) ->
        if not Ti?
            return require path

        fileInfo = Ti.Filesystem.getFile(Ti.Filesystem.resourcesDirectory, path)

        if fileInfo.exists()
            return JSON.parse fileInfo.read().getText()
        else
            throw new Error("#{path}: no such file.")



    ###*
    in Titanium, "A instanceof B" sometimes fails.
    this is the alternative.

    @method isInstance
    @static
    @param {Object} instance
    @param {Function} class
    @return {Boolean} A is instance of B
    ###
    @isInstance: (instance, Class) ->

        if not Ti?
            return instance instanceof Class

        return false if not instance?.constructor
        return true if Class is Object

        className = Class.name

        until instance.constructor is Object

            return true if instance.constructor.name is className

            instance = Object.getPrototypeOf instance

        return false

    @deepEqual: (a, b) ->

        deepEqual(a, b)


    @clone: (v) ->

        clone v


    ###*
    Check if the given value is instanceof Promise.

    "val instanceof Promise" fails when native Promise and its polyfill are mixed
    ###
    @isPromise: (val) ->

        typeof val?.then is 'function'


module.exports = Util