#! /usr/bin/env ruby -w

#Represents a Rogerian psychiatrist
class Shrink

  #initializes 'memory' of Eliza.
  def initialize()
    @he="he"
    @she="she"
    @they="they"
  end

  #read a statement and convert it to a psychiatric response.
  def generateResponse(blather)
    #downcase for ease of substitution
    blather = blather.downcase

    # filter out words like "well" or "perhaps" from the beginning
    blather.gsub!(/^(well|perhaps|anyway|actually),?\s+/i, '')

    # change 'you', 'your', etc. to uppercase 'I', 'MY'
    blather.gsub!(/\byour\b/,"MY")
    blather.gsub!(/\byou\b/,'I')

    #Replace 'my' with 'your', 'me' with 'you', 'I' with 'you', etc.
    blather.gsub!(/\bmy\b/,"your")
    blather.gsub!(/\bme\b/,"you")
    blather.gsub!(/\bi\b/,'you')

    #Get future references -- note that these do NOT change the immediate output
    hePat=/.*\b(your (father|brother|(ex-?)?(husband|boyfriend)))\b.*/
    shePat = /.*\b(your (mother|sister|(ex-?)?(wife|girlfriend)))\b.*/
    theyPat = /.*\b(your (parents|friends|siblings|colleagues|classmates))\b.*/
    @he=blather.sub(hePat, '\1').chomp if blather =~ hePat
    @she=blather.sub(shePat, '\1').chomp if blather =~ shePat
    @they=blather.sub(theyPat, '\1').chomp if blather =~ theyPat

    # handle "always" and "never" responses
    if blather =~ /\b(always|never)\b/
      return "CAN YOU BE MORE SPECIFIC?"
    end

    # handle "are you" questions
    if blather =~ /^are I (.+?)\?*$/
      return "IS IT IMPORTANT IF I AM #{$1.upcase}?"
    end

    #Sub in past references, but only for the 1st occurrence or it looks weird
    blather.sub!(/\b(he|him)\b/, @he)
    blather.sub!(/\b(she|her)\b/, @she)
    blather.sub!(/\bthey\b/, @they)

    #Deal with name
    namePat=/.*\byour name is (\w+).*/
    @name=blather.sub(namePat,'\1')
    blather.sub!(namePat,'nice to meet you, \1.  How can I help you')

    # add some empathy for sad words
    if blather =~ /\b(sad|depressed|upset|hurt|angry|frustrated)\b/
      empathetic_responses = [
        "THAT SOUNDS DIFFICULT. ",
        "I CAN HEAR THE PAIN IN YOUR WORDS. ",
        "THAT MUST BE HARD FOR YOU. "
      ]
      prefix = empathetic_responses.sample
      return prefix + "TELL ME MORE ABOUT " + blather.upcase + "?"
    end

    #results are uppercased, for aesthetics.
    return blather.upcase + "?"
  end
end


#main -- reads from standard input unless -test is the first parameter.
eliza = Shrink.new()
if ARGV[0] == "-test"
    ['My girlfriend never listens to me',
      "I think she might be deaf",
      "yes",
      "I am afraid of clowns",
      "Well, they just seem creepy",
      "Also, when I was a kid, a clown killed my dad",
      "Are you a clown in disguise?",
      # test "always" response
      "I always feel nervous",
      # test "never" response
      "My parents never understand me",
      # test "Are you" questions
      "Are you listening to me?",
      "Are you a real doctor?",
      # test word filtering
      "Perhaps my friends don't like me",
      "Well, I suppose that makes sense",
      "Actually, I think I'm getting better",
      # test "they" memory
      "My colleagues are very competitive",
      "They make me feel inadequate",
      "Sometimes they ignore my ideas",
      # Test empathetic responses
      "I am feeling very sad today",
      "My boss makes me frustrated",
      "I feel so depressed lately",
    ].each do |stmt|
        puts stmt
        puts eliza.generateResponse(stmt)
        puts
    end
else
  while line = gets
    response = eliza.generateResponse line
    puts response
  end
end