vimlike_textview for mikutter (development preview)

vimlike_textview.rb

#!/usr/bin/env ruby
#-*- coding: utf-8 -*-

require 'gtk2'
require 'gtksourceview2'

class VimlikeTextView < Gtk::SourceView

  attr_accessor :current_mode, :default_bgcolor, :insert_bgcolor, :visual_bgcolor, :select

  @@hook_keys_normal = ['a', 'A', 'i', 'I', 'o', 'O', 'v', 'h', 'j', 'k', 'l', 'u', 'p', 'P', 'x', 'X', 'BackSpace']
  @@hook_keys_insert = ['Escape']
  @@hook_keys_visual = ['Escape', 'h', 'j', 'k', 'l', 'y', 'x']

  @@hist_limit = 8000
  @@post_history = []
  @@post_history_ptr = 0


  module Mode
    NORMAL = 0
    INSERT = 1
    VISUAL = 2
  end

  def initialize
    super
    self.show_line_numbers = true

    @select = false
    @current_mode = Mode::NORMAL

    update_bgcolor
    @default_bgcolor = Gdk::Color.new(0xffff, 0xffff, 0xffff)
    @insert_bgcolor  = Gdk::Color.new(0xffff, 0xffff, 0xaaaa)
    @visual_bgcolor  = Gdk::Color.new(0xffff, 0xaaaa, 0xffff)

    @history_stack = []
    @history_stack.push([self.buffer.text, self.buffer.cursor_position])
    @stack_ptr = 0
    @isundo = false

    add_signal(self.buffer)

    signal_connect('key_press_event') { |w, e|
      key = Gdk::Keyval.to_name(e.keyval)
      @isundo = (current_mode == Mode::NORMAL) and (key == 'u')

      case current_mode
      when Mode::NORMAL
        case key
        when 'a'
          self.current_mode = Mode::INSERT
          update_bgcolor
          self.move_cursor(Gtk::MOVEMENT_VISUAL_POSITIONS, 1, @select)
        when 'A'
          self.current_mode = Mode::INSERT
          update_bgcolor
          self.move_cursor(Gtk::MOVEMENT_PARAGRAPH_ENDS, 1, @select)
        when 'i'
          self.current_mode = Mode::INSERT
          update_bgcolor
        when 'I'
          self.current_mode = Mode::INSERT
          update_bgcolor
          self.move_cursor(Gtk::MOVEMENT_PARAGRAPH_ENDS, -1, @select)
        when 'o'
          self.current_mode = Mode::INSERT
          update_bgcolor
          self.move_cursor(Gtk::MOVEMENT_PARAGRAPH_ENDS, 1, @select)
          self.insert_at_cursor("\n")
        when 'O'
          self.current_mode = Mode::INSERT
          update_bgcolor
          self.move_cursor(Gtk::MOVEMENT_PARAGRAPH_ENDS, -1, @select)
          self.insert_at_cursor("\n")
          self.move_cursor(Gtk::MOVEMENT_DISPLAY_LINES, -1, @select)
        when 'v'
          self.current_mode = Mode::VISUAL
          update_bgcolor
          self.select = true
        when 'h'
          self.move_cursor(Gtk::MOVEMENT_VISUAL_POSITIONS, -1, @select)
        when 'j'
          self.move_cursor(Gtk::MOVEMENT_DISPLAY_LINES, 1, @select)
        when 'k'
          self.move_cursor(Gtk::MOVEMENT_DISPLAY_LINES, -1, @select)
        when 'l'
          self.move_cursor(Gtk::MOVEMENT_VISUAL_POSITIONS, 1, @select)
        when 'u'
          self.undo
        when 'p'
          self.move_cursor(Gtk::MOVEMENT_VISUAL_POSITIONS, 1, @select)
          self.paste_clipboard
        when 'P'
          self.paste_clipboard
        when 'x'
          self.delete_from_cursor(Gtk::DELETE_CHARS, 1)
        when 'X'
          self.delete_from_cursor(Gtk::DELETE_CHARS, -1)
        when 'BackSpace'
          self.move_cursor(Gtk::MOVEMENT_VISUAL_POSITIONS, -1, @select)
        end
        true

      when Mode::INSERT
        case key
        when 'Escape'
          self.current_mode = Mode::NORMAL
          update_bgcolor
        end
        @@hook_keys_insert.include? key

      when Mode::VISUAL
        case key
        when 'Escape'
          self.current_mode = Mode::NORMAL
          update_bgcolor
          self.select = false
          self.select_all(false)
        when 'h'
          self.move_cursor(Gtk::MOVEMENT_VISUAL_POSITIONS, -1, @select)
        when 'j'
          self.move_cursor(Gtk::MOVEMENT_DISPLAY_LINES, 1, @select)
        when 'k'
          self.move_cursor(Gtk::MOVEMENT_DISPLAY_LINES, -1, @select)
        when 'l'
          self.move_cursor(Gtk::MOVEMENT_VISUAL_POSITIONS, 1, @select)
        when 'y'
          self.copy_clipboard
          self.select = false
          self.select_all(false)
          self.current_mode = Mode::NORMAL
          update_bgcolor
        when 'x'
          self.delete_from_cursor(Gtk::DELETE_CHARS, 1)
        end
        true

      end

    }

  end

  def update_bgcolor
    case current_mode
    when Mode::NORMAL
      modify_base(Gtk::STATE_NORMAL, default_bgcolor)
    when Mode::INSERT
      modify_base(Gtk::STATE_NORMAL, insert_bgcolor)
    when Mode::VISUAL
      modify_base(Gtk::STATE_NORMAL, visual_bgcolor)
    end
  end


  def self.pushGlobalStack(text)
    @@post_history_ptr = @@post_history.length
    @@post_history.push(text) end


  def add_signal(buffer)
    buffer.signal_connect('changed') {
      if not @isundo then
        @history_stack += @history_stack[@stack_ptr..-2].reverse
        self.push_buffer
        @stack_ptr = @history_stack.length - 1
      end
    }
    buffer
  end

  # 現在のバッファと最新の履歴が異なっていればスタックに現在の状態を追加
  def push_buffer
    if @history_stack == nil then
      @history_stack = [['', 0]]
    end
    if self.buffer.text != '' then
      if @history_stack[-1][0] != self.buffer.text then
        @history_stack.push([self.buffer.text, self.buffer.cursor_position])
      end
      if @history_stack.length > @@hist_limit then
        @history_stack = @history_stack[(@history_stack.length - @@hist_limit)..-1]
      end
    end
  end

  # undoの実装．バッファの内容を変更すると自動的に履歴スタックに追加されるので，
  # 履歴スタックに追加したら最新の履歴を捨てる
  def undo
    top = @history_stack[@stack_ptr]
    if top != nil then
      if top[0] == self.buffer.text then
        # 最新履歴が現在の状態と同じなら，2番目の履歴を参照
        decStackPtr
        second = @history_stack[@stack_ptr]
        if second != nil then
          self.buffer.set_text(second[0])
          self.buffer.place_cursor(self.buffer.get_iter_at_offset(second[1]))
        else # 上から2番目が空
          self.buffer.set_text('')
        end
      else
        self.buffer.set_text(top[0])
        self.buffer.place_cursor(self.buffer.get_iter_at_offset(top[1]))
      end
    else # 履歴スタックが空
      self.buffer.set_text('')
    end
  end

  def incStackPtr
    if @history_stack.length > @stack_ptr + 1 then
      @stack_ptr += 1
    end
  end

  def decStackPtr
    if @stack_ptr > 0 then
      @stack_ptr -= 1
    end
  end

  def undoGlobalStack
    if @@post_history != []
      if not defined? @is_global_undo
        @is_global_undo = true
      end
      if @is_global_undo == false
        @@post_history_ptr = (@@post_history_ptr - 1) % @@post_history.length
        @@post_history_ptr = (@@post_history_ptr - 1) % @@post_history.length
      end
      self.buffer.set_text(@@post_history[@@post_history_ptr])
      @@post_history_ptr = (@@post_history_ptr - 1) % @@post_history.length
      @is_global_undo = true
    end
  end

  def redoGlobalStack
    if @@post_history != []
      if not defined? @is_global_undo
        @is_global_undo = false
      end
      if @is_global_undo == true
        @@post_history_ptr = (@@post_history_ptr + 1) % @@post_history.length
        @@post_history_ptr = (@@post_history_ptr + 1) % @@post_history.length
      end
      self.buffer.set_text(@@post_history[@@post_history_ptr])
      @@post_history_ptr = (@@post_history_ptr + 1) % @@post_history.length
      @is_global_undo = false
    end
  end


end

vtv = VimlikeTextView.new
w = Gtk::Window.new
w.add(vtv)
w.set_size_request(300,200)
w.signal_connect('key_press_event') { |w, e|
  if Gdk::Keyval.to_name(e.keyval) == 'q' then
    Gtk.main_quit
  end
}
w.signal_connect('destroy') {
  Gtk.main_quit
}
w.show_all

Gtk.main