#!/usr/bin/env ruby

# browse --
# This script generates a directory browser, which lists the working 
# directory and allow you to open files or subdirectories by 
# double-clicking. 

require 'tk'

# Create a scrollbar on the right side of the main window and a listbox 
# on the left side.

listbox = TkListbox.new(nil, 'relief'=>'sunken', 
			'width'=>20, 'height'=>20, 'setgrid'=>'yes') {|l|
  TkScrollbar.new(nil, 'command'=>proc{|*args| l.yview *args}) {|s|
    pack('side'=>'right', 'fill'=>'y')
    l.yscrollcommand(proc{|first,last| s.set(first,last)})
  }

  pack('side'=>'left', 'fill'=>'both', 'expand'=>'yes')
}

root = TkRoot.new
root.minsize(1,1)

# The procedure below is invoked to open a browser on a given file;  if the 
# file is a directory then another instance of this program is invoked; if 
# the file is a regular file then the Mx editor is invoked to display 
# the file. 

def browse (dir, file)
  file = dir + File::Separator + file if dir != '.'
  type = File.ftype(file)
  if type == 'directory'
    system($0 + ' ' + file + ' &')
  else
    if type == 'file'
      if ENV['EDITOR']
	system(ENV['EDITOR'] + ' ' + file + ' &')
      else
	system('xedit ' + file + ' &')
      end
    else
      STDOUT.print "\"#{file}\" isn't a directory or regular file"
    end
  end
end

# Fill the listbox with a list of all the files in the directory (run 
# the "ls" command to get that information).

dir = ARGV[0] ?  ARGV[0] : '.'
open("|ls -a #{dir}", 'r'){|fid| fid.readlines}.each{|fname|
  listbox.insert('end', fname.chomp)
}

# Set up bindings for the browser.

Tk.bind_all('Control-c', proc{root.destroy})
listbox.bind('Double-Button-1', 
	     proc{TkSelection.get.each{|f| browse dir, f}})

Tk.mainloop
