# Thanks to @indirect, gist.github.com/2922427

namespace :source do

def find_and_replace_in_source_files(find, replace)
  puts "Search and replace #{find.inspect} => #{replace.inspect}"

  files = %w[ .autotest .rspec .rvmrc Gemfile Procfile config.ru ].select{|f| File.exist?(f) }
  directories = %w[app config lib public script spec test] # exclude bin, db, doc, log, and tmp
  directories.each do |d|
    files += Dir[File.join(d, "**/*.{rb,rake,haml,erb,builder,js,coffee,css,scss}")]
  end

  files.each do |file_name|
    text = File.open(file_name, 'r'){ |file| file.read }
    if text.gsub!(find, replace)
      puts "rewriting #{file_name}..."
      File.open(file_name, 'w'){|file| file.write(text)}
    end
  end
end

desc "Replace all tabs in source code files with two spaces"
task :detab do
  find_and_replace_in_source_files("\t", " ")
end

desc "Remove trailing whitespace on the ends of lines"
task :detrail do
  find_and_replace_in_source_files(/ +$/, '')
end

desc "Replace all instances of {pattern} with {result}"
task :gsub, :pattern, :result do |t, args|
  find_and_replace_in_source_files(Regexp.new(args[:pattern] || ENV['PATTERN']), args[:result] || ENV['RESULT'])
end

end