focus.rb

#!/usr/bin/env ruby

# focus - convenient window switching in ratpoison
#
# Dan Fitch dan@rapt.us
#
# based on select.sh - originally copyright 2003 <bkhl@elektrubadur.se>
# 
# Example: focus cmus in a screen or start a new one containing it
#
#     bind a exec focus 'cmus' 'screen cmus'
#
# USAGE:
#   
#   focus <operation> <type> <regex>
#
# Returns 1 if nothing matches.
#   
#   When operation is "last":
#     re-run the last regex with the given type
#   When operation is "select":
#     toggle the two most recently accessed matching windows
#   When operation is "cycle":
#     go through all of the matching windows in order
#   When operation is "cycleback":
#     go through all of the matching windows in order, backwards
#   When operation is "menu":
#     show menu of all of the matching windows
#
#   When type is "last":
#     re-run the last regex with the given operation
#   When type is "title":
#     match by title
#   When type is "class":
#     match by class
#
# If the window has a screen session, attempt to select the first matching screen
#
# TODO:
#   menu mode
#   ordering is a little wacky on simple focus, like it's skipping when it shouldn't have to
#   use knowledge of screens (the physical ones)
#

$: << File.dirname(__FILE__)
require 'ratpoison'

windows = Ratpoison.windows_array
operation = nil
type = nil
args = nil

if ARGV[0] == "last"
  operation = Ratpoison.getenv "focus_last_operation"
  args = Ratpoison.getenv "focus_last_args"
else
  operation = ARGV[0]
  Ratpoison.setenv "focus_last_operation #{operation}"
end

if ARGV[1] == "last"
  type = Ratpoison.getenv "focus_last_type"
  args = Ratpoison.getenv "focus_last_args"
else
  type = ARGV[1]
  Ratpoison.setenv "focus_last_type #{type}"
end

if not args
  exit 2 if not ARGV[2]
  args = ARGV[2..-1].join(' ')
  Ratpoison.setenv "focus_last_args #{args}"
end

regex = /#{args}/i


current_window = windows.detect {|x| x.status == "*"}

filtered_windows = windows.find_all do |win|
  case type
  when /title/:
    regex.match win.title
  when /class/:
    regex.match win.class
  else
    raise "Unknown match type #{type}"
  end
end

if filtered_windows.length == 0
  puts "no windows match #{type} #{regex}"
  exit 1
end

# TODO: This should probably build a list of all screen titles that match so 
# that cycling works at screen granularity instead of window granularity
window = case operation
when /cycle/:
  # Cycle things that match

  if filtered_windows.detect { |x| x.number == current_window.number }
    # Select by number
    cycle = filtered_windows.sort_by { |x| x.number }
    current_index = cycle.index current_window
    index =
    if current_index
      if operation[/back/]:
        current_index + 1
      else
        current_index - 1
      end
    else
      0
    end
    puts "selecting #{index} by number, current is #{current_index}" if $DEBUG
  else
    # Current window does not match -- select the most recent or least recent
    cycle = filtered_windows.sort_by { |x| x.last_access }
    index = 
    if operation[/back/]:
      0
    else
      cycle.length - 1
    end
    puts "selecting #{index} by recent" if $DEBUG
  end

  index = cycle.length - 1 if index < 0
  index = 0 if index > cycle.length - 1
  puts "moving to #{index}" if $DEBUG

  cycle[index]

when /menu/:
  # Select via menu (TODO)
  menu = filtered_windows.sort_by { |x| x.last_access }
  if menu.length == 1 then
    menu[0]
  else
    nil
  end
else
  # Select the most recent non-current window
  select = filtered_windows.sort_by { |x| x.last_access }

  if current_window
    select.delete_if { |x| x.number == current_window.number }
  end

  if select.length == 0
    nil
  else
    puts select.map { |x| "#{x.number} #{x.title}" } if $DEBUG
    select[0]
  end
end

Ratpoison.select window.number if window
window ||= current_window

if window and window.screen_session
  screen = window.screen_session.detect { |x| regex.match x.title }
  exit 1 if window == current_window and screen.number == window.screen_session.number
  Ratpoison::ScreenSession.select screen.number if screen
else
  exit 1 if window == current_window
end