marky.php

<?php

$stdin = fopen ("php://stdin","r");

$brain = array();

print "> ";
while ( $line = trim(fgets($stdin)) ) {
  if ( $line == "q" ) break;

  // break into words array
  $words = explode(" ", $line);

  // if we dont have at least 2 words (one chain) skip for input  
  if ( count($words) < 2 ) continue;

  /////////////
  // Train the Markov Brain with this new sentence chain

  // pop off the first word
  $word = $words[0];

  // this loop treads the sentence as a chain of words, where $word -> $next_word
  for ( $i=1; $i < count($words); $i++ ) {
    $next_word = $words[$i];

    // if our marky bot hasn't experienced this word yet, initialize it's array
    if ( ! array_key_exists($word, $brain) ) $brain[$word] = array();

    // learn the word!
    $brain[$word][] = $next_word;

    $word = $next_word;
  }

  // This part adds an "end of sentence" marker. We treat it kind of like a word. 
  if ( ! array_key_exists($word, $brain) ) $brain[$word] = array();
  $brain[$word][] = ".";

print_r($brain);

  ////////////
  // Generate a Markov Chain based on a random word from the sentence

  $word = $words[array_rand($words)];
  $chain = array();

  while ( $word != "." ) {
    // Pull a random word out of the list of words our Marky bot has seen follow our given word
    // in the past. We know $brain[$word] will always exist because we create everything in $words
    // in the learning phase.
    print "\$word = $word\n";
    if (!array_key_exists($word,$brain)) exit;

    $possible_next_words = $brain[$word];

    $word = $possible_next_words[array_rand($possible_next_words)];
    print "chosen word: $word\n";
    $chain[] = $word;
  }

  print "marky > " . implode(" ", $chain) . "\n";

  print "> ";
}


?>