view/ncurses/ncurses_view.rb

# ncurses_view.rb: the class definition of Edmaru::Ncurses::NcursesView
#
# Copyright (C) 2007 Takashi Nakamoto
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License version 2 as
# published by the Free Software Foundation.
#
# This program is distributed in the hope that it will be useful, but
# WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with this program; if not, write to the Free Software
# Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
# 02110-1301 USA.
#

require "ncurses"
require "ncurses/ncurses_color.rb"

module Edmaru::Ncurses

  #Concrete class by Ncurses library
  class NcursesView
    include Edmaru::View

    #Initilizing Ncurses library for Edmaru.
    def init_ui
      # The standard initialization.
      Ncurses::initscr
      Ncurses::start_color
      Ncurses::raw
      Ncurses::stdscr.keypad(TRUE)
      Ncurses::noecho

      # set default color
      Edmaru::Ncurses::NcursesColor::init_colors(@config)

      # "refresh" should be called here to show other sub windows.
      Ncurses::refresh

      #This view's main loop continues as long as this flag is false.
      @exit_flag = false
    end

    #Initialize NCurses windows.
    def init_windows
      @windows[0].init_ncurses_window(0, 0,
                                      ncurses_allocated_column,
                                      ncurses_allocated_line - 1)

      @mini_window.init_ncurses_window(0, ncurses_allocated_line - 1,
                                       ncurses_allocated_column, 1)
    end


    #Total column size allocated for this view.
    def ncurses_allocated_column
      a1 = Array.new
      a2 = Array.new
      Ncurses::getmaxyx(Ncurses::stdscr, a1, a2)
      return a2[0]
    end

    #Total numbe of lines allocated for this view.
    def ncurses_allocated_line
      a1 = Array.new
      a2 = Array.new
      Ncurses::getmaxyx(Ncurses::stdscr, a1, a2)
      return a1[0]
    end

    def request_resize(window, row)
      if window == @mini_window
        max_mini_window_row = (ncurses_allocated_line * 0.2).to_i
        if max_mini_window_row <= 0
          max_mini_window_row = 1
        end

        if row <= max_mini_window_row &&
            window.ncurses_allocated_row < row
          @windows[0].ncurses_move_resize(0, 0,
                                          ncurses_allocated_column,
                                          ncurses_allocated_line - row)
          @mini_window.ncurses_move_resize(0, ncurses_allocated_line - row,
                                           ncurses_allocated_column, row)
          return true
        elsif window.ncurses_allocated_row > row
          @windows[0].ncurses_move_resize(0, 0,
                                          ncurses_allocated_column,
                                          ncurses_allocated_line - row)
          @mini_window.ncurses_move_resize(0, ncurses_allocated_line - row,
                                           ncurses_allocated_column, row)
          return true
        end
      end

      return false
    end

    #Set _exit_flag_ as true to exit the running main loop.
    #
    #=== Warning
    #This method doesn't exit the running main loop as soon as it is
    #called.
    def exit_main_loop
      @exit_flag = true
    end

    #Main loop to catch key events.
    def main_loop
      while true
        ch = Ncurses::getch

        case ch
        when 0x21..0x7f #Normal ASCII codes.
          @event_manager.handle("KeyPress:#{ch.chr}")
        when 0x01..0x1a #Control-a - Control-z
          tmp_ch = ch + "a"[0] - 1
          @event_manager.handle("KeyPress:control-#{tmp_ch.chr}")
        when 0x1b
          @event_manager.handle("KeyPress:escape")
        when 0x20
          @event_manager.handle("KeyPress:space")
        when Ncurses::KEY_DOWN
          @event_manager.handle("KeyPress:down-arrow")
        when Ncurses::KEY_UP
          @event_manager.handle("KeyPress:up-arrow")
        when Ncurses::KEY_LEFT
          @event_manager.handle("KeyPress:left-arrow")
        when Ncurses::KEY_RIGHT
          @event_manager.handle("KeyPress:right-arrow")
        when Ncurses::KEY_DC
          @event_manager.handle("KeyPress:delete")
        when Ncurses::KEY_BACKSPACE
          @event_manager.handle("KeyPress:backspace")
        else
          @event_manager.handle("KeyPress:#{ch}")
        end

        #Exit this main loop.
        if @exit_flag
          break
        end
      end
    end

    #Beep once.
    def beep
      Ncurses::beep
    end

    #Terminate this view instance and free allocated memory of Ncurses
    #library.
    def terminate_ui
      Ncurses::endwin
    end
  end
end