# frozen_string_literal: true
#
#   irb/init.rb - irb initialize module
#   	by Keiju ISHITSUKA(keiju@ruby-lang.org)
#

module IRB # :nodoc:
  @CONF = {}
  @INITIALIZED = false
  # Displays current configuration.
  #
  # Modifying the configuration is achieved by sending a message to IRB.conf.
  #
  # See IRB@Configuration for more information.
  def IRB.conf
    @CONF
  end

  def @CONF.inspect
    array = []
    for k, v in sort{|a1, a2| a1[0].id2name <=> a2[0].id2name}
      case k
      when :MAIN_CONTEXT, :__TMP__EHV__
        array.push format("CONF[:%s]=...myself...", k.id2name)
      when :PROMPT
        s = v.collect{
          |kk, vv|
          ss = vv.collect{|kkk, vvv| ":#{kkk.id2name}=>#{vvv.inspect}"}
          format(":%s=>{%s}", kk.id2name, ss.join(", "))
        }
        array.push format("CONF[:%s]={%s}", k.id2name, s.join(", "))
      else
        array.push format("CONF[:%s]=%s", k.id2name, v.inspect)
      end
    end
    array.join("\n")
  end

  # Returns the current version of IRB, including release version and last
  # updated date.
  def IRB.version
    format("irb %s (%s)", @RELEASE_VERSION, @LAST_UPDATE_DATE)
  end

  def IRB.initialized?
    !!@INITIALIZED
  end

  # initialize config
  def IRB.setup(ap_path, argv: ::ARGV)
    IRB.init_config(ap_path)
    IRB.init_error
    IRB.parse_opts(argv: argv)
    IRB.run_config
    IRB.validate_config
    IRB.load_modules

    unless @CONF[:PROMPT][@CONF[:PROMPT_MODE]]
      fail UndefinedPromptMode, @CONF[:PROMPT_MODE]
    end
    @INITIALIZED = true
  end

  # @CONF default setting
  def IRB.init_config(ap_path)
    # default configurations
    unless ap_path and @CONF[:AP_NAME]
      ap_path = File.join(File.dirname(File.dirname(__FILE__)), "irb.rb")
    end
    @CONF[:VERSION] = version
    @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[:USE_SINGLELINE] = false unless defined?(ReadlineInputMethod)
    @CONF[:USE_COLORIZE] = (nc = ENV['NO_COLOR']).nil? || nc.empty?
    @CONF[:USE_AUTOCOMPLETE] = ENV.fetch("IRB_USE_AUTOCOMPLETE", "true") != "false"
    @CONF[:COMPLETOR] = ENV.fetch("IRB_COMPLETOR", "regexp").to_sym
    @CONF[:INSPECT_MODE] = true
    @CONF[:USE_TRACER] = false
    @CONF[:USE_LOADER] = false
    @CONF[:IGNORE_SIGINT] = true
    @CONF[:IGNORE_EOF] = false
    @CONF[:USE_PAGER] = true
    @CONF[:EXTRA_DOC_DIRS] = []
    @CONF[:ECHO] = nil
    @CONF[:ECHO_ON_ASSIGNMENT] = nil
    @CONF[:VERBOSE] = nil

    @CONF[:EVAL_HISTORY] = nil
    @CONF[:SAVE_HISTORY] = 1000

    @CONF[:BACK_TRACE_LIMIT] = 16

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

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

    @CONF[:CONTEXT_MODE] = 4 # use a copy of TOPLEVEL_BINDING
    @CONF[:SINGLE_IRB] = false

    @CONF[:MEASURE] = false
    @CONF[:MEASURE_PROC] = {}
    @CONF[:MEASURE_PROC][:TIME] = proc { |context, code, line_no, &block|
      time = Time.now
      result = block.()
      now = Time.now
      puts 'processing time: %fs' % (now - time) if IRB.conf[:MEASURE]
      result
    }
    # arg can be either a symbol for the mode (:cpu, :wall, ..) or a hash for
    # a more complete configuration.
    # See https://github.com/tmm1/stackprof#all-options.
    @CONF[:MEASURE_PROC][:STACKPROF] = proc { |context, code, line_no, arg, &block|
      return block.() unless IRB.conf[:MEASURE]
      success = false
      begin
        require 'stackprof'
        success = true
      rescue LoadError
        puts 'Please run "gem install stackprof" before measuring by StackProf.'
      end
      if success
        result = nil
        arg = { mode: arg || :cpu } unless arg.is_a?(Hash)
        stackprof_result = StackProf.run(**arg) do
          result = block.()
        end
        case stackprof_result
        when File
          puts "StackProf report saved to #{stackprof_result.path}"
        when Hash
          StackProf::Report.new(stackprof_result).print_text
        else
          puts "Stackprof ran with #{arg.inspect}"
        end
        result
      else
        block.()
      end
    }
    @CONF[:MEASURE_CALLBACKS] = []

    @CONF[:LC_MESSAGES] = Locale.new

    @CONF[:AT_EXIT] = []

    @CONF[:COMMAND_ALIASES] = {
      # Symbol aliases
      :'$' => :show_source,
      :'@' => :whereami,
    }
  end

  def IRB.set_measure_callback(type = nil, arg = nil, &block)
    added = nil
    if type
      type_sym = type.upcase.to_sym
      if IRB.conf[:MEASURE_PROC][type_sym]
        added = [type_sym, IRB.conf[:MEASURE_PROC][type_sym], arg]
      end
    elsif IRB.conf[:MEASURE_PROC][:CUSTOM]
      added = [:CUSTOM, IRB.conf[:MEASURE_PROC][:CUSTOM], arg]
    elsif block_given?
      added = [:BLOCK, block, arg]
      found = IRB.conf[:MEASURE_CALLBACKS].find{ |m| m[0] == added[0] && m[2] == added[2] }
      if found
        found[1] = block
        return added
      else
        IRB.conf[:MEASURE_CALLBACKS] << added
        return added
      end
    else
      added = [:TIME, IRB.conf[:MEASURE_PROC][:TIME], arg]
    end
    if added
      IRB.conf[:MEASURE] = true
      found = IRB.conf[:MEASURE_CALLBACKS].find{ |m| m[0] == added[0] && m[2] == added[2] }
      if found
        # already added
        nil
      else
        IRB.conf[:MEASURE_CALLBACKS] << added if added
        added
      end
    else
      nil
    end
  end

  def IRB.unset_measure_callback(type = nil)
    if type.nil?
      IRB.conf[:MEASURE_CALLBACKS].clear
    else
      type_sym = type.upcase.to_sym
      IRB.conf[:MEASURE_CALLBACKS].reject!{ |t, | t == type_sym }
    end
    IRB.conf[:MEASURE] = nil if IRB.conf[:MEASURE_CALLBACKS].empty?
  end

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

  # option analyzing
  def IRB.parse_opts(argv: ::ARGV)
    load_path = []
    while opt = argv.shift
      case opt
      when "-f"
        @CONF[:RC] = false
      when "-d"
        $DEBUG = true
        $VERBOSE = true
      when "-w"
        Warning[:deprecated] = $VERBOSE = true
      when /^-W(.+)?/
        opt = $1 || argv.shift
        case opt
        when "0"
          $VERBOSE = nil
        when "1"
          $VERBOSE = false
        else
          Warning[:deprecated] = $VERBOSE = true
        end
      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"
        if /^-/ !~ argv.first
          @CONF[:INSPECT_MODE] = argv.shift
        else
          @CONF[:INSPECT_MODE] = true
        end
      when "--noinspect"
        @CONF[:INSPECT_MODE] = false
      when "--no-pager"
        @CONF[:USE_PAGER] = false
      when "--singleline", "--readline", "--legacy"
        @CONF[:USE_SINGLELINE] = true
      when "--nosingleline", "--noreadline"
        @CONF[:USE_SINGLELINE] = false
      when "--multiline", "--reidline"
        if opt == "--reidline"
          warn <<~MSG.strip
            --reidline is deprecated, please use --multiline instead.
          MSG
        end

        @CONF[:USE_MULTILINE] = true
      when "--nomultiline", "--noreidline"
        if opt == "--noreidline"
          warn <<~MSG.strip
            --noreidline is deprecated, please use --nomultiline instead.
          MSG
        end

        @CONF[:USE_MULTILINE] = false
      when /^--extra-doc-dir(?:=(.+))?/
        opt = $1 || argv.shift
        @CONF[:EXTRA_DOC_DIRS] << opt
      when "--echo"
        @CONF[:ECHO] = true
      when "--noecho"
        @CONF[:ECHO] = false
      when "--echo-on-assignment"
        @CONF[:ECHO_ON_ASSIGNMENT] = true
      when "--noecho-on-assignment"
        @CONF[:ECHO_ON_ASSIGNMENT] = false
      when "--truncate-echo-on-assignment"
        @CONF[:ECHO_ON_ASSIGNMENT] = :truncate
      when "--verbose"
        @CONF[:VERBOSE] = true
      when "--noverbose"
        @CONF[:VERBOSE] = false
      when "--colorize"
        @CONF[:USE_COLORIZE] = true
      when "--nocolorize"
        @CONF[:USE_COLORIZE] = false
      when "--autocomplete"
        @CONF[:USE_AUTOCOMPLETE] = true
      when "--noautocomplete"
        @CONF[:USE_AUTOCOMPLETE] = false
      when "--regexp-completor"
        @CONF[:COMPLETOR] = :regexp
      when "--type-completor"
        @CONF[:COMPLETOR] = :type
      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 "--script"
        noscript = false
      when "--noscript"
        noscript = true
      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 "-v", "--version"
        print IRB.version, "\n"
        exit 0
      when "-h", "--help"
        require_relative "help"
        IRB.print_usage
        exit 0
      when "--"
        if !noscript && (opt = argv.shift)
          @CONF[:SCRIPT] = opt
          $0 = opt
        end
        break
      when /^-./
        fail UnrecognizedSwitch, opt
      else
        if noscript
          argv.unshift(opt)
        else
          @CONF[:SCRIPT] = opt
          $0 = opt
        end
        break
      end
    end

    load_path.collect! do |path|
      /\A\.\// =~ path ? path : File.expand_path(path)
    end
    $LOAD_PATH.unshift(*load_path)
  end

  # Run the config file
  def IRB.run_config
    if @CONF[:RC]
      irbrc_files.each do |rc|
        load rc
      rescue StandardError, ScriptError => e
        warn "Error loading RC file '#{rc}':\n#{e.full_message(highlight: false)}"
      end
    end
  end

  IRBRC_EXT = "rc"

  def IRB.rc_file(ext)
    prepare_irbrc_name_generators

    # When irbrc exist in default location
    if (rcgen = @existing_rc_name_generators.first)
      return rcgen.call(ext)
    end

    # When irbrc does not exist in default location
    rc_file_generators do |rcgen|
      return rcgen.call(ext)
    end

    # When HOME and XDG_CONFIG_HOME are not available
    nil
  end

  def IRB.irbrc_files
    prepare_irbrc_name_generators
    @irbrc_files
  end

  def IRB.validate_config
    conf[:IRB_NAME] = conf[:IRB_NAME].to_s

    irb_rc = conf[:IRB_RC]
    unless irb_rc.nil? || irb_rc.respond_to?(:call)
      raise_validation_error "IRB.conf[:IRB_RC] should be a callable object. Got #{irb_rc.inspect}."
    end

    back_trace_limit = conf[:BACK_TRACE_LIMIT]
    unless back_trace_limit.is_a?(Integer)
      raise_validation_error "IRB.conf[:BACK_TRACE_LIMIT] should be an integer. Got #{back_trace_limit.inspect}."
    end

    prompt = conf[:PROMPT]
    unless prompt.is_a?(Hash)
      msg = "IRB.conf[:PROMPT] should be a Hash. Got #{prompt.inspect}."

      if prompt.is_a?(Symbol)
        msg += " Did you mean to set `IRB.conf[:PROMPT_MODE]`?"
      end

      raise_validation_error msg
    end

    eval_history = conf[:EVAL_HISTORY]
    unless eval_history.nil? || eval_history.is_a?(Integer)
      raise_validation_error "IRB.conf[:EVAL_HISTORY] should be an integer. Got #{eval_history.inspect}."
    end
  end

  def IRB.raise_validation_error(msg)
    raise TypeError, msg, @irbrc_files
  end

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

  class << IRB
    private

    def prepare_irbrc_name_generators
      return if @existing_rc_name_generators

      @existing_rc_name_generators = []
      @irbrc_files = []
      rc_file_generators do |rcgen|
        irbrc = rcgen.call(IRBRC_EXT)
        if File.exist?(irbrc)
          @irbrc_files << irbrc
          @existing_rc_name_generators << rcgen
        end
      end
      generate_current_dir_irbrc_files.each do |irbrc|
        @irbrc_files << irbrc if File.exist?(irbrc)
      end
      @irbrc_files.uniq!
    end

    # enumerate possible rc-file base name generators
    def rc_file_generators
      if irbrc = ENV["IRBRC"]
        yield proc{|rc| rc == "rc" ? irbrc : irbrc+rc}
      end
      if xdg_config_home = ENV["XDG_CONFIG_HOME"]
        irb_home = File.join(xdg_config_home, "irb")
        if File.directory?(irb_home)
          yield proc{|rc| irb_home + "/irb#{rc}"}
        end
      end
      if home = ENV["HOME"]
        yield proc{|rc| home+"/.irb#{rc}"}
        if xdg_config_home.nil? || xdg_config_home.empty?
          yield proc{|rc| home+"/.config/irb/irb#{rc}"}
        end
      end
    end

    # possible irbrc files in current directory
    def generate_current_dir_irbrc_files
      current_dir = Dir.pwd
      %w[.irbrc irbrc _irbrc $irbrc].map { |file| "#{current_dir}/#{file}" }
    end

    def set_encoding(extern, intern = nil, override: true)
      verbose, $VERBOSE = $VERBOSE, nil
      Encoding.default_external = extern unless extern.nil? || extern.empty?
      Encoding.default_internal = intern unless intern.nil? || intern.empty?
      [$stdin, $stdout, $stderr].each do |io|
        io.set_encoding(extern, intern)
      end
      if override
        @CONF[:LC_MESSAGES].instance_variable_set(:@override_encoding, extern)
      else
        @CONF[:LC_MESSAGES].instance_variable_set(:@encoding, extern)
      end
    ensure
      $VERBOSE = verbose
    end
  end
end
