class Sprockets::Rails::StaticCompiler

def compile
  manifest = {}
  env.each_logical_path do |logical_path|
    next unless compile_path?(logical_path)
    if asset = env.find_asset(logical_path)
      manifest[logical_path] = write_asset(asset)
    end
  end
  write_manifest(manifest) if @manifest
end

def compile_path?(logical_path)
  paths.each do |path|
    case path
    when Regexp
      return true if path.match(logical_path)
    when Proc
      return true if path.call(logical_path)
    else
      return true if File.fnmatch(path.to_s, logical_path)
    end
  end
  false
end

def initialize(env, target, paths, options = {})
  @env = env
  @target = target
  @paths = paths
  @digest = options.fetch(:digest, true)
  @manifest = options.fetch(:manifest, true)
  @manifest_path = options.delete(:manifest_path) || target
  @zip_files = options.delete(:zip_files) || /\.(?:css|html|js|svg|txt|xml)$/
end

def path_for(asset)
  @digest ? asset.digest_path : asset.logical_path
end

def write_asset(asset)
  path_for(asset).tap do |path|
    filename = File.join(target, path)
    FileUtils.mkdir_p File.dirname(filename)
    asset.write_to(filename)
    asset.write_to("#{filename}.gz") if filename.to_s =~ @zip_files
  end
end

def write_manifest(manifest)
  FileUtils.mkdir_p(@manifest_path)
  File.open("#{@manifest_path}/manifest.yml", 'wb') do |f|
    YAML.dump(manifest, f)
  end
end