[QUIZ][SOLUTION] LSRC Name Picker (#129)

Here is my solution to this week's Ruby quiz. It is my first program to
use Ruby/Tk, and, after using it, will probably be my last.

The
picker's main procedure as follows: Upon startup, the program creates a
pseudo terminal command line displaying a short "conversation" between
the program and the user, with a picture of a star above it the whole
time (ASCII-art, as I was loathe to include, other non-plain-text files
in the solution). It then quickly scrolls through a listbox with a
terminal-ish feel, saying that it is "scanning" for one worthy of
receiving the prize.It then switches to a view with the scrambled name
of the recipient at the bottom, and suspensefully has the characters
fly up towards the top, placing themselves in the correct order. If
known, the picker then displays the recipient's hometown and
organization below the name.

To
implement the persistence - well, what could be sexier than having the
program modify its own source code? If it detects the "-a" command-line
argument, rather than running the picker, the program will instead
append source code to itself that adds the attendee's name to an array
(with -o and -t options for organization and hometown, respectively).
Similarly, after being run, the program modifies  itself to add the
winner to the $previous_winners array. Originally, the add_code method
implemented a "Schlemiel the Painter" algorithm, as all appended code
had to come before Tk.mainloop; by using at_exit, I have managed to
avoid that so that the program can just do a plain 'ol append.

To seed the program with test data, I just grabbed the list of last names from http://www.census.gov/genealogy/names/dist.all.last, saved it as "names.dat" and used the following script (LSRCPicker.rb was the name of my program's file):

File.open("names.dat") do |f|
    names = f.readlines.map{|l|l.split[0].capitalize}
    300.times do
        name = names[rand(names.length)] + " " + name = names[rand(names.length)]
        org = nil
        if rand(2)==1
            org = names[rand(names.length)] + " and " + names[rand(names.length)] + " Consulting, LLC"
        end
        home = names[rand(names.length)] + "ville, " + %w{MA CA NY MI FL MO AZ TX AR IL}.sort_by{rand}.first
        if
 org
            `ruby LSRCPicker.rb -a #{name} -o #{org} -t #{home}`
        else
            `ruby LSRCPicker.rb -a #{name} -t #{home}`
        end
    end
end

Here is my actual solution:

####Door prize picekr for LSRC. The program creates persistance by modifying its
####own source code.
####Command line usage: Without arguments, it runs the name picker
####With the -a argument, combined with the optional -o and -t arguments,
####it adds an attendee's name, organization, and hometown respectively to the program
require 'tk'
require 'enumerator'

$attendees = []
$organization = {}
$hometown = {}

$previous_winners = [nil]


###Adds code_str to this source file right before Tk::mainloop is invoked
def add_code(code_str)
 
 File.open($0, "a") do |f|
    f.puts code_str
  end
end

class Array
  def first_satisfies_i
    each_with_index {|el, i| return i if yield el}
    nil
  end
  
  def map_with_index
    mapped = []
    each_with_index {|el, i| mapped[i] = yield(el,i)}
    mapped
  end
end

def get_arg(name)
  arg_proc = proc {|arg| arg =~ /^-/}
   if (i = ARGV.index name)
    ARGV[(i+1)..((j=ARGV[(i+1)..-1].first_satisfies_i(&arg_proc)) ? i+j : -1)
      ].join(' ')
  end
end

###Code to check and process people being added from the command line
unless ARGV==[]
  name, org, town = ['-a','-o','-t'].map{|n| get_arg n}
  add_code <<-EOC
  
    $attendees <<
 #{name.inspect}
    $organization[#{name.inspect}] = #{org.inspect}
    $hometown[#{name.inspect}] = #{town.inspect}
  EOC
  exit
end

class TkVariable
  ###Makes updating values as easy as it should be
  def []=(*args)
    v = self.value
    v[*args[0...-1]] = args.last
    self.value = v
  end
end

###Simulates a user typing text into a console
###The only way I could get it to wait for the typing to finish before
###continuing was to have it yield when done
def type(tkvar, text, sleep_t=0.05)
  Thread.new(tkvar, text) do |tkvar, text|
    until text.empty?
      sleep sleep_t
      tkvar.value, text[0,1] = tkvar.value+text[0,1], ""
    end
    yield
  end
end

def char_fly(tkvars,
 char_pos, dest_pos)
  incr =(dest_pos.to_f-char_pos)/(tkvars.length-1)
  c = tkvars.last.value[char_pos, 1]
  return if " "==c
  Thread.new(tkvars, char_pos, incr, c) do |tkvars, char_in, incr, c|
    tkvars.reverse.each_cons(2) do |tkvar_prev, tkvar|
      tkvar_prev[char_in.round, 1] = ' '
      char_in += incr
      tkvar[char_in.round, 1] = c
      sleep 0.1
    end
  end
end

root = TkRoot.new {
  title 'Lone Star Ruby Conf Door Prize Picker'
  background '#000000'}
TkMessage.new(root){
  background '#000000'
  borderwidth 0
  justify 'center'
  font 'courier'
  foreground '#C0C0C0'
  text <<EOD
       
 .+                  
        +h:                 
       -shh`                
      `shhhs                
`........./hhhhy---:--::::.     
`:shhhhyyyyyssyhhhhhhhys/`      
   `:shhhhyo+oyhhhhhy+.         
      `/syyyhhhhyyy:            
       `ohhhhhyssoy:            
      
 /yhhhdhhhysyh:           
      .shhyo- `:oyhhh`          
      oho-        -+ys          
     -:`             -.         
EOD
}.grid



content_frame = TkFrame.new(root){
  background '#000000'
  grid{rowspan 60; colspan '100'; sticky "ew"}}

##Holds a pseudo-console
console_frame = TkFrame.new(content_frame) {
  background '#000000'
  width 100
  grid{rowspan 100; colspan '100'; sticky "ew"}}
console_var = TkVariable.new " "*100
console = TkLabel.new(console_frame){
  background '#000000'
  foreground '#C0C0C0'
  justify
 'left'
  font TkFont.new('Courier'){size 40}
  grid{rowspan 100; colspan '100'; sticky "ew"}
  height 7
}.textvariable(console_var)

##Holds the list that scrolls all the attendees names
list_frame = TkFrame.new(content_frame)  {
  background '#000000'
  grid{rowspan 100; colspan '100'; sticky "ew"}}
list = TkListbox.new(list_frame){
  background '#000000'
  foreground '#C0C0C0'
  borderwidth 0
  selectforeground '#000000'
  selectbackground '#C0C0C0'
  highlightthickness 0
  width 75
  font TkFont.new('Courier'){size 40}
  listvariable [' ']*10
  height 10
}

#Displays the word "scanning" when the list of attendees scrolled by
#There is significant flicker involved with this method, as everything is drawn as soon
#as I programmatically make the change.
#I was unable to remove the flicker (perhaps by suspending drawng
 routines, but
#could not find the class responsible in the docs). I had signicant trouble getting updating
#the value of #the listvariable to work; replacing the listvariable worked but was very slow.
#This approach is the best I came up with.
scanning_display = TkListbox.new(list_frame){
  foreground '#000000'
  background '#000000'
  highlightthickness 0
  borderwidth 0
  width 25
  font TkFont.new('Courier'){size 40}
  listvariable [' ']*10
  height 10}
  
flying_text_frame = TkFrame.new(content_frame) {
  background '#000000'
  width 100}
  
flying_textboxes = ([nil]*10).map {
  [(v=TkVariable.new(" "*100)),
    TkEntry.new(flying_text_frame){
      background '#000000'
      foreground '#C0C0C0'
      borderwidth 0
     
 font TkFont.new('Courier'){size 40}
      width 100
      grid{rowspan 100; colspan '100'; sticky "ew"}
    }.textvariable(v)]}.map{|arr|arr[0]}

TkGrid.grid(list, scanning_display)

##The main procedure of the program
run_picker = proc do
  if $ran
    return
  else
    $ran = true
  end
  $attendees = $attendees.sort_by {|n| n.split.reverse.join(' ')}
  type(console_var,"\n") do
    sleep 2
    console_var.value += "Why do you wake me, mortal?\n>"
    sleep 2; type(console_var, "I seek your wisdom and guidance.\n") do
      sleep 2; console_var.value += "What perplexes you?\n>"; sleep 2
      type(console_var, "Tell me the one most worthy of
 "+
          "receiving this prize.\n") do
        sleep 2
        console_var.value += "Very well; "
        sleep 0.5
        console_var.value += "the time is right for that decision."
        lvar = TkVariable.new $attendees
        sleep 1
        list.listvariable lvar
        scanning_display.listvariable(TkVariable.new(["scanning"]))
        scanning_display.itemconfigure(0, "background"=> "#C0C0C0")
        $attendees[0..-10].each_with_index do |el, i|
         
 list.yview(i)
          list.selection_set(i)
          sleep 0.01
        end
        list_frame.ungrid
        sleep 0.2
        console_var.value += "\nI have found your worthy candidate." + 
          " Watch and let the mystery reveal itself."
        sleep 3
        console_frame.ungrid
        chosen = nil
        chosen = $attendees[rand($attendees.length)
          ] while $previous_winners.include? chosen
        scrambled =
 chosen.split(//).map_with_index{|el, i|
          [rand,el,i]}.sort.map{|arr|arr[1..2]}
        scrambled_str = scrambled.map{|el| el[0]}.join
        flying_textboxes.last.value = " "*(50-scrambled_str.length/2)+
          scrambled_str
        flying_text_frame.grid
        sleep 1
        until flying_textboxes.first.value.include? chosen
          ci=rand(scrambled_str.length)
          char_fly(flying_textboxes,  (50-scrambled_str.length/2)+ci,
           
 (50-scrambled_str.length/2)+scrambled[ci][1])
          sleep 0.1
        end
        t = $hometown[chosen]
        o = $organization[chosen]
        flying_textboxes[1][50-t.length/2,t.length] = t if t
        flying_textboxes[2][50-o.length/2,o.length] = o if o
        add_code <<-EOC
        
          $previous_winners << #{chosen.inspect}
        EOC
      end
    end
  end
end

root.bind('FocusIn',
 &run_picker)
at_exit {Tk.mainloop}


       
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