danielkalen/coffee-register

child_process = require 'child_process'
fs = require 'fs-jetpack'
path = require 'path'
COFFEE_CACHE_DIR = if process.env.COFFEE_CACHE_DIR then path.resolve(process.env.COFFEE_CACHE_DIR) else path.join __dirname,'..','.cache'
COFFEE_NO_CACHE = process.env.COFFEE_NO_CACHE
serveCached = not COFFEE_NO_CACHE

## ==========================================================================
## require.extensions patch
## ========================================================================== 
register = (extensions=[], options)->
    options = getOptions(options)
    
    md5 = require 'md5'
    coffeescript = if options.version is 1 then require('coffee-script') else require('coffeescript')
    
    targetExtensions = [].concat(extensions, '.coffee')
    fs.dir(COFFEE_CACHE_DIR)
    cachedFiles = fs.list(COFFEE_CACHE_DIR).filter (file)-> file.slice(-3) is '.js'

    loadFile = (module, filename)->
        content = fs.read(filename)
        hash = md5(content)
        cachedFile = "#{hash}.js"
        cachedFilePath = path.join COFFEE_CACHE_DIR,cachedFile

        if serveCached and cachedFiles.indexOf(cachedFile) isnt -1
            compiledContent = fs.read cachedFilePath
        else
            compiledContent = coffeescript.compile content, {filename, bare:true, inlineMap:true}
            fs.write cachedFilePath, compiledContent
        
        module._compile compiledContent, filename


    for extension in targetExtensions when extension
        Object.defineProperty require.extensions, extension,
            writable: not options.lock
            configurable: true
            enumerable: true
            value: loadFile

    return register

getOptions = (options={})->
    options.lock ?= false
    options.version ?= 2
    return options


## ==========================================================================
## child_process.fork patch
## ========================================================================== 
if child_process
    origFork = child_process.fork
    coffeeBinary = path.resolve './node_modules/coffeescript/bin/coffee'

    child_process.fork = (filePath, args, options)->
        if path.extname(filePath) is '.coffee'
            unless Array.isArray(args)
                options = args or {}
                args = []
            
            args = [filePath].concat args
            filePath = coffeeBinary
        
        origFork filePath, args, options



## ==========================================================================
## Source map support (necessary for cached files)
## ========================================================================== 
### istanbul ignore next ###
if process.env.SOURCE_MAPS or process.env.SOURCE_MAP
    require('@danielkalen/source-map-support').install(hookRequire:true)



module.exports = register()