git.r.bdr.sh - rbdr/dotfiles/blob - vim/tmp/command_t/ruby/command-t/prompt.rb

   1 # Copyright 2010 Wincent Colaiuta. All rights reserved.
   2 #
   3 # Redistribution and use in source and binary forms, with or without
   4 # modification, are permitted provided that the following conditions are met:
   5 #
   6 # 1. Redistributions of source code must retain the above copyright notice,
   7 #    this list of conditions and the following disclaimer.
   8 # 2. Redistributions in binary form must reproduce the above copyright notice,
   9 #    this list of conditions and the following disclaimer in the documentation
  10 #    and/or other materials provided with the distribution.
  11 #
  12 # THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
  13 # AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  14 # IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  15 # ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR CONTRIBUTORS BE
  16 # LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
  17 # CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
  18 # SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  19 # INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
  20 # CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
  21 # ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
  22 # POSSIBILITY OF SUCH DAMAGE.
  23
  24 module CommandT
  25   # Abuse the status line as a prompt.
  26   class Prompt
  27     attr_accessor :abbrev
  28
  29     def initialize
  30       @abbrev     = ''  # abbreviation entered so far
  31       @col        = 0   # cursor position
  32       @has_focus  = false
  33     end
  34
  35     # Erase whatever is displayed in the prompt line,
  36     # effectively disposing of the prompt
  37     def dispose
  38       ::VIM::command 'echo'
  39       ::VIM::command 'redraw'
  40     end
  41
  42     # Clear any entered text.
  43     def clear!
  44       @abbrev = ''
  45       @col    = 0
  46       redraw
  47     end
  48
  49     # Insert a character at (before) the current cursor position.
  50     def add! char
  51       left, cursor, right = abbrev_segments
  52       @abbrev = left + char + cursor + right
  53       @col += 1
  54       redraw
  55     end
  56
  57     # Delete a character to the left of the current cursor position.
  58     def backspace!
  59       if @col > 0
  60         left, cursor, right = abbrev_segments
  61         @abbrev = left.chop! + cursor + right
  62         @col -= 1
  63         redraw
  64       end
  65     end
  66
  67     # Delete a character at the current cursor position.
  68     def delete!
  69       if @col < @abbrev.length
  70         left, cursor, right = abbrev_segments
  71         @abbrev = left + right
  72         redraw
  73       end
  74     end
  75
  76     def cursor_left
  77       if @col > 0
  78         @col -= 1
  79         redraw
  80       end
  81     end
  82
  83     def cursor_right
  84       if @col < @abbrev.length
  85         @col += 1
  86         redraw
  87       end
  88     end
  89
  90     def cursor_end
  91       if @col < @abbrev.length
  92         @col = @abbrev.length
  93         redraw
  94       end
  95     end
  96
  97     def cursor_start
  98       if @col != 0
  99         @col = 0
 100         redraw
 101       end
 102     end
 103
 104     def redraw
 105       if @has_focus
 106         prompt_highlight = 'Comment'
 107         normal_highlight = 'None'
 108         cursor_highlight = 'Underlined'
 109       else
 110         prompt_highlight = 'NonText'
 111         normal_highlight = 'NonText'
 112         cursor_highlight = 'NonText'
 113       end
 114       left, cursor, right = abbrev_segments
 115       components = [prompt_highlight, '>>', 'None', ' ']
 116       components += [normal_highlight, left] unless left.empty?
 117       components += [cursor_highlight, cursor] unless cursor.empty?
 118       components += [normal_highlight, right] unless right.empty?
 119       components += [cursor_highlight, ' '] if cursor.empty?
 120       set_status *components
 121     end
 122
 123     def focus
 124       unless @has_focus
 125         @has_focus = true
 126         redraw
 127       end
 128     end
 129
 130     def unfocus
 131       if @has_focus
 132         @has_focus = false
 133         redraw
 134       end
 135     end
 136
 137   private
 138
 139     # Returns the @abbrev string divided up into three sections, any of
 140     # which may actually be zero width, depending on the location of the
 141     # cursor:
 142     #   - left segment (to left of cursor)
 143     #   - cursor segment (character at cursor)
 144     #   - right segment (to right of cursor)
 145     def abbrev_segments
 146       left    = @abbrev[0, @col]
 147       cursor  = @abbrev[@col, 1]
 148       right   = @abbrev[(@col + 1)..-1] || ''
 149       [left, cursor, right]
 150     end
 151
 152     def set_status *args
 153       # see ':help :echo' for why forcing a redraw here helps
 154       # prevent the status line from getting inadvertantly cleared
 155       # after our echo commands
 156       ::VIM::command 'redraw'
 157       while (highlight = args.shift) and  (text = args.shift) do
 158         text = VIM::escape_for_single_quotes text
 159         ::VIM::command "echohl #{highlight}"
 160         ::VIM::command "echon '#{text}'"
 161       end
 162       ::VIM::command 'echohl None'
 163     end
 164   end # class Prompt
 165 end # module CommandT