image in css, html from url to uri

imageToUri.coffee

fs = require('fs')
cheerio = require('cheerio')

staticFolder = 'static'
imgFolder = 'img'
cssFolder = 'css'
cssRoot = __dirname + '/' + cssFolder

htmlFolder = 'views'
htmlRoot = __dirname + '/../application/' + htmlFolder

minSize = 300
minFileSize = minSize * minSize * 3
skipFiles = ['.sass-cache', '.DS_Store', 'http://', 'sass', 'template.css', 'template_bho.css', 'ie.css', 'print.css', 'mail']


Core = module.exports =
    getFileList: (folderPath = null, cb) ->
        console.log 'getFileList begin ', arguments
        return null  unless folderPath

        return fs.readdirSync(folderPath) unless cb

        fs.readdir folderPath, (err, files) ->
            (if (err) then cb(null) else cb(files))


    getFile: (path = null, cb) ->
        console.log 'getFile begin ', arguments
        return null  unless path

        unless cb
            f = fs.readFileSync(path)
            if f
                return f.toString()
            else
                return null

        fs.readFile path, (err, data) ->
            (if (err) then cb(null) else cb(data.toString()))

    saveFile: (path = null, data = null, cb) ->
        console.log 'saveFile begin ', arguments
        return null  unless path
        return null  unless data

        if typeof(data) is 'string'
            data = new Buffer(data, 'utf8')

        unless cb
            return fs.writeFileSync(path, data)

        fs.writeFile path, data, (err) ->
            if(err)
                console.log 'err = ' ,err
            else
                console.log 'save success = ', path


    getCSSUrl: (cssData = null, isDuplicate = null, cb) ->
        console.log 'getCSSUrl begin ', arguments
        return null  unless cssData

        css = cssData
        ma = css.match(/url\(\.\.[^ \;\,]*\)/g)
        result = []

        return ma  unless isDuplicate

        for i of ma
            m = ma[i]
            result.push m  if result.indexOf(m) < 0

        return result

    imageToUri: (data = null, format = 'png') ->
        console.log 'imageToUri begin ', arguments
        return null  unless data

        base64data = new Buffer(data).toString('base64')
        return imgString = 'url(data:image/' + format + ';base64,' + base64data + ')'

    replacePath: (originalPath = '') ->
        console.log 'replacePath begin ', arguments
        # url(../img/landing/bg_num_web1.png)
        originalPath = originalPath.substr(4, originalPath.length - 5)
        return __dirname + originalPath.replace(/\.\./i, '')

    replaceSrcPath: (originalPath = '') ->
        console.log 'replaceSrcPath begin ', arguments
        # /static/img/landing/bg_num_web1.png
        # originalPath = originalPath.substr(4, originalPath.length - 5)
        _regex = new RegExp('/' + staticFolder, 'i')
        return __dirname + originalPath.replace( _regex, '')


    replaceCSS: (cssPath = null, cb) ->
        console.log 'replaceCSS begin ', arguments
        return null  unless cssPath

        data = @getFile(cssPath)

        if data
            urls = @getCSSUrl(data)

            if urls and urls.length

                for i of urls
                    oldUrl = urls[i]
                    newUrl = @replacePath(urls[i])
                    img = @getFile(newUrl)

                    if(img.length < minFileSize)
                        uri = @imageToUri(img)
                        data = data.replace(oldUrl, uri)
                        @saveFile(cssPath, data)

        else
            console.log 'can not find ==> ', cssPath

    replaceHtml: (htmlPath = null, cb) ->
        console.log 'replaceHtml begin ', arguments
        return null  unless htmlPath

        data = @getFile(htmlPath)

        if data
            $ = cheerio.load(data)
            $('img').each (index, item)=>
                $item = $(item)
                if $item.attr('data-i18n-img')
                    return

                src = $item.attr('src')
                if src and src.indexOf('<?') < 0
                    src = @replaceSrcPath(src)
                    img = @getFile(src)
                    uri = @imageToUri(img)

                    if img.length < minFileSize
                        $item.attr('src', uri)


            @saveFile(htmlPath, $.html())

        else
            console.log 'can not find ==> ', cssPath




# image in CSS
cssfiles = Core.getFileList(cssRoot)
for i of cssfiles
    cName = cssfiles[i]
    cPath = cssRoot + '/' + cName

    if skipFiles.indexOf(cName) >= 0
        continue

    Core.replaceCSS(cPath)


# image in HTML or other views/template
htmlfiles = Core.getFileList(htmlRoot)
for i of htmlfiles
    hName = htmlfiles[i]
    hPath = htmlRoot + '/' + hName

    if skipFiles.indexOf(hName) >= 0
        continue

    Core.replaceHtml(hPath)