module Rufo::Command

def self.find_dot_rufo(dir)
  dir  = File.expand_path(dir)
  file = File.join(dir, ".rufo")
  if File.exist?(file)
    return file
  end
  parent_dir = File.dirname(dir)
  return if parent_dir == dir
  find_dot_rufo(parent_dir)
end

def self.format(code, dir)
  formatter = Rufo::Formatter.new(code)
  dot_rufo = find_dot_rufo(dir)
  if dot_rufo
    begin
      formatter.instance_eval(File.read(dot_rufo))
    rescue => ex
      STDERR.puts "Error evaluating #{dot_rufo}"
      raise ex
    end
  end
  formatter.format
  formatter.result
end

def self.format_args(args, want_check)
  files = []
  args.each do |arg|
    if Dir.exist?(arg)
      files.concat Dir["#{arg}/**/*.rb"]
    elsif File.exist?(arg)
      files << arg
    else
      STDERR.puts "Error: file or directory not found: #{arg}"
    end
  end
  changed = false
  files.each do |file|
    success   = format_file file, want_check
    changed ||= success
  end
  exit 1 if changed
end

def self.format_file(filename, want_check)
  code   = File.read(filename)
  begin
    result = format(code, File.dirname(filename))
  rescue Rufo::SyntaxError
    # We ignore syntax errors as these might be template files
    # with .rb extension
    STDERR.puts "Error: #{filename} has syntax errors"
    return true
  end
  if code != result
    if want_check
      STDERR.puts "Error: formatting #{filename} produced changes"
    else
      File.write(filename, result)
      puts "Format: #{filename}"
    end
    return true
  end
  false
rescue Rufo::SyntaxError
  STDERR.puts "Error: the given text in #{filename} is not a valid ruby program (it has syntax errors)"
  exit 1
rescue Rufo::Bug => ex
  STDERR.puts "You've found a bug!"
  STDERR.puts "It happened while trying to format the file #{filename}"
  STDERR.puts "Please report it to https://github.com/asterite/rufo/issues with code that triggers it"
  STDERR.puts
  raise ex
end

def self.format_stdin(want_check)
  code   = STDIN.read
  result = format(code, Dir.getwd)
  if want_check
    exit 1 if result != code
  else
    print result
  end
rescue Rufo::SyntaxError
  STDERR.puts "Error: the given text is not a valid ruby program (it has syntax errors)"
  exit 1
rescue Rufo::Bug => ex
  STDERR.puts "You've found a bug!"
  STDERR.puts "Please report it to https://github.com/asterite/rufo/issues with code that triggers it"
  STDERR.puts
  raise ex
end

def self.parse_options(argv)
  want_check = false
  OptionParser.new do |opts|
    opts.banner = "Usage: rufo files or dirs [options]"
    opts.on("-c", "--check", "Only check formating changes") do
      want_check = true
    end
    opts.on("-h", "--help", "Show this help") do
      puts opts
      exit
    end
  end.parse!(argv)
  want_check
end

def self.run(argv)
  want_check = parse_options(argv)
  if argv.empty?
    format_stdin want_check
  else
    format_args argv, want_check
  end
end