#
#   irb/init.rb - irb initialize module
#   	$Release Version: 0.9.5$
#   	$Revision$
#   	by Keiju ISHITSUKA(keiju@ruby-lang.org)
#
# --
#
#
#

module IRB

  # initialize config
  def IRB.setup(ap_path)
    IRB.init_config(ap_path)
    IRB.init_error
    IRB.parse_opts
    IRB.run_config
    IRB.load_modules

    unless @CONF[:PROMPT][@CONF[:PROMPT_MODE]]
      IRB.fail(UndefinedPromptMode, @CONF[:PROMPT_MODE])
    end
  end

  # @CONF default setting
  def IRB.init_config(ap_path)
    # class instance variables
    @TRACER_INITIALIZED = false

    # default configurations
    unless ap_path and @CONF[:AP_NAME]
      ap_path = File.join(File.dirname(File.dirname(__FILE__)), "irb.rb")
    end
    @CONF[:AP_NAME] = File::basename(ap_path, ".rb")

    @CONF[:IRB_NAME] = "irb"
    @CONF[:IRB_LIB_PATH] = File.dirname(__FILE__)

    @CONF[:RC] = true
    @CONF[:LOAD_MODULES] = []
    @CONF[:IRB_RC] = nil

    @CONF[:MATH_MODE] = false
    @CONF[:USE_READLINE] = false unless defined?(ReadlineInputMethod)
    @CONF[:INSPECT_MODE] = nil
    @CONF[:USE_TRACER] = false
    @CONF[:USE_LOADER] = false
    @CONF[:IGNORE_SIGINT] = true
    @CONF[:IGNORE_EOF] = false
    @CONF[:ECHO] = nil
    @CONF[:VERBOSE] = nil

    @CONF[:EVAL_HISTORY] = nil
    @CONF[:SAVE_HISTORY] = nil

    @CONF[:BACK_TRACE_LIMIT] = 16

    @CONF[:PROMPT] = {
      :NULL => {
	:PROMPT_I => nil,
	:PROMPT_N => nil,
	:PROMPT_S => nil,
	:PROMPT_C => nil,
	:RETURN => "%s\n"
      },
      :DEFAULT => {
	:PROMPT_I => "%N(%m):%03n:%i> ",
	:PROMPT_N => "%N(%m):%03n:%i> ",
	:PROMPT_S => "%N(%m):%03n:%i%l ",
	:PROMPT_C => "%N(%m):%03n:%i* ",
	:RETURN => "=> %s\n"
      },
      :CLASSIC => {
	:PROMPT_I => "%N(%m):%03n:%i> ",
	:PROMPT_N => "%N(%m):%03n:%i> ",
	:PROMPT_S => "%N(%m):%03n:%i%l ",
	:PROMPT_C => "%N(%m):%03n:%i* ",
	:RETURN => "%s\n"
      },
      :SIMPLE => {
	:PROMPT_I => ">> ",
	:PROMPT_N => ">> ",
	:PROMPT_S => nil,
	:PROMPT_C => "?> ",
	:RETURN => "=> %s\n"
      },
      :INF_RUBY => {
	:PROMPT_I => "%N(%m):%03n:%i> ",
#	:PROMPT_N => "%N(%m):%03n:%i> ",
	:PROMPT_N => nil,
	:PROMPT_S => nil,
	:PROMPT_C => nil,
	:RETURN => "%s\n",
	:AUTO_INDENT => true
      },
      :XMP => {
	:PROMPT_I => nil,
	:PROMPT_N => nil,
	:PROMPT_S => nil,
	:PROMPT_C => nil,
	:RETURN => "    ==>%s\n"
      }
    }

    @CONF[:PROMPT_MODE] = (STDIN.tty? ? :DEFAULT : :NULL)
    @CONF[:AUTO_INDENT] = false

    @CONF[:CONTEXT_MODE] = 3 # use binding in function on TOPLEVEL_BINDING
    @CONF[:SINGLE_IRB] = false

#    @CONF[:LC_MESSAGES] = "en"
    @CONF[:LC_MESSAGES] = Locale.new

    @CONF[:DEBUG_LEVEL] = 1
  end

  def IRB.init_error
    @CONF[:LC_MESSAGES].load("irb/error.rb")
  end

  FEATURE_IOPT_CHANGE_VERSION = "1.9.0"

  # option analyzing
  def IRB.parse_opts
    load_path = []
    while opt = ARGV.shift
      case opt
      when "-f"
	@CONF[:RC] = false
      when "-m"
	@CONF[:MATH_MODE] = true
      when "-d"
	$DEBUG = true
      when /^-r(.+)?/
	opt = $1 || ARGV.shift
	@CONF[:LOAD_MODULES].push opt if opt
      when /^-I(.+)?/
        opt = $1 || ARGV.shift
	load_path.concat(opt.split(File::PATH_SEPARATOR)) if opt
      when '-U'
	set_encoding("UTF-8", "UTF-8")
      when /^-E(.+)?/, /^--encoding(?:=(.+))?/
	opt = $1 || ARGV.shift
	set_encoding(*opt.split(':', 2))
      when "--inspect"
	@CONF[:INSPECT_MODE] = true
      when "--noinspect"
	@CONF[:INSPECT_MODE] = false
      when "--readline"
	@CONF[:USE_READLINE] = true
      when "--noreadline"
	@CONF[:USE_READLINE] = false
      when "--echo"
	@CONF[:ECHO] = true
      when "--noecho"
	@CONF[:ECHO] = false
      when "--verbose"
	@CONF[:VERBOSE] = true
      when "--noverbose"
	@CONF[:VERBOSE] = false
      when /^--prompt-mode(?:=(.+))?/, /^--prompt(?:=(.+))?/
	opt = $1 || ARGV.shift
	prompt_mode = opt.upcase.tr("-", "_").intern
	@CONF[:PROMPT_MODE] = prompt_mode
      when "--noprompt"
	@CONF[:PROMPT_MODE] = :NULL
      when "--inf-ruby-mode"
	@CONF[:PROMPT_MODE] = :INF_RUBY
      when "--sample-book-mode", "--simple-prompt"
	@CONF[:PROMPT_MODE] = :SIMPLE
      when "--tracer"
	@CONF[:USE_TRACER] = true
      when /^--back-trace-limit(?:=(.+))?/
	@CONF[:BACK_TRACE_LIMIT] = ($1 || ARGV.shift).to_i
      when /^--context-mode(?:=(.+))?/
	@CONF[:CONTEXT_MODE] = ($1 || ARGV.shift).to_i
      when "--single-irb"
	@CONF[:SINGLE_IRB] = true
      when /^--irb_debug=(?:=(.+))?/
	@CONF[:DEBUG_LEVEL] = ($1 || ARGV.shift).to_i
      when "-v", "--version"
	print IRB.version, "\n"
	exit 0
      when "-h", "--help"
	require "irb/help"
	IRB.print_usage
	exit 0
      when "--"
	if opt = ARGV.shfit
	  @CONF[:SCRIPT] = opt
	  $0 = opt
	end
        break
      when /^-/
	IRB.fail UnrecognizedSwitch, opt
      else
	@CONF[:SCRIPT] = opt
	$0 = opt
	break
      end
    end
    if RUBY_VERSION >= FEATURE_IOPT_CHANGE_VERSION
      load_path.collect! do |path|
	/\A\.\// =~ path ? path : File.expand_path(path)
      end
    end
    $LOAD_PATH.unshift(*load_path)

  end

  # running config
  def IRB.run_config
    if @CONF[:RC]
      begin
	load rc_file
      rescue LoadError, Errno::ENOENT
      rescue # StandardError, ScriptError
	print "load error: #{rc_file}\n"
	print $!.class, ": ", $!, "\n"
	for err in $@[0, $@.size - 2]
	  print "\t", err, "\n"
	end
      end
    end
  end

  IRBRC_EXT = "rc"
  def IRB.rc_file(ext = IRBRC_EXT)
    if !@CONF[:RC_NAME_GENERATOR]
      rc_file_generators do |rcgen|
	@CONF[:RC_NAME_GENERATOR] ||= rcgen
	if File.exist?(rcgen.call(IRBRC_EXT))
	  @CONF[:RC_NAME_GENERATOR] = rcgen
	  break
	end
      end
    end
    @CONF[:RC_NAME_GENERATOR].call ext
  end

  # enumerate possible rc-file base name generators
  def IRB.rc_file_generators
    if irbrc = ENV["IRBRC"]
      yield proc{|rc| rc == "rc" ? irbrc : irbrc+rc}
    end
    if home = ENV["HOME"]
      yield proc{|rc| home+"/.irb#{rc}"}
    end
    home = Dir.pwd
    yield proc{|rc| home+"/.irb#{rc}"}
    yield proc{|rc| home+"/irb#{rc.sub(/\A_?/, '.')}"}
    yield proc{|rc| home+"/_irb#{rc}"}
    yield proc{|rc| home+"/$irb#{rc}"}
  end

  # loading modules
  def IRB.load_modules
    for m in @CONF[:LOAD_MODULES]
      begin
	require m
      rescue LoadError => err
	warn err.backtrace[0] << ":#{err.class}: #{err}"
      end
    end
  end


  DefaultEncodings = Struct.new(:external, :internal)
  class << IRB
    private
    def set_encoding(extern, intern = nil)
      verbose, $VERBOSE = $VERBOSE, nil
      Encoding.default_external = extern unless extern.nil? || extern.empty?
      Encoding.default_internal = intern unless intern.nil? || intern.empty?
      @CONF[:ENCODINGS] = IRB::DefaultEncodings.new(extern, intern)
      [$stdin, $stdout, $stderr].each do |io|
	io.set_encoding(extern, intern)
      end
      @CONF[:LC_MESSAGES].instance_variable_set(:@encoding, extern)
    ensure
      $VERBOSE = verbose
    end
  end
end