Initial working version

admin.js

@@ -0,0 +1,77 @@
+var Postwriter = {
+
+	size_slider_changed: function( event, ui ) {
+		Postwriter.describe_chain_size( ui.value );
+	},
+
+	describe_chain_size: function( value ) {
+		if ( value < 0 || value > 10 )
+			return;
+
+		jQuery( 'span#postwriter_chain_size_description' ).html( [
+			'F\'tang Crazy',
+			'Extremely Random',
+			'Very Random',
+			'Random',
+			'Less Random',
+			'Barely Random',
+			'Boring',
+			'Yawn.'
+		][ value - 1 ] );
+	},
+
+};
+
+jQuery( document ).ready( function() {
+
+	Postwriter.chain_size_slider = jQuery( 'div#postwriter_chain_size' ).slider( {
+		value: 4,
+		min: 1,
+		max: 8,
+		step: 1,
+		slide: Postwriter.size_slider_changed
+	} );
+
+	Postwriter.describe_chain_size( 4 );
+
+	jQuery( 'span#postwriter_generate' ).click( function( event ) {
+		jQuery( 'span#postwriter_loading' ).show();
+		jQuery( 'span#postwriter_generate' ).hide();
+
+		var chain_size = Postwriter.chain_size_slider.slider( 'value' );
+		var chain_by = jQuery( 'select#postwriter_chain_by option:selected' ).val();
+
+		var data = {
+			action: 'postwriter_generate',
+			chain_size: chain_size,
+			chain_by: chain_by
+		};
+
+		jQuery.post( ajaxurl, data, function( data ) {
+			jQuery( 'span#postwriter_loading' ).hide();
+			jQuery( 'span#postwriter_generate' ).show();
+
+			try {
+				var response = jQuery.parseJSON( data );
+			} catch ( e ) {
+				var response = data;
+			};
+
+			if ( 'object' == typeof( response ) && response.hasOwnProperty( 'title' ) && response.hasOwnProperty( 'body' ) ) {
+				jQuery( 'input#title' ).val( response.title ).trigger( 'focus' );
+
+				if ( switchEditors && switchEditors.go )
+					switchEditors.go( null, 'html' );
+
+				jQuery( 'textarea#content' ).val( response.body );
+			} else {
+				var error = response.error ? response.error : response;
+				if ( ! error )
+					error = 'Empty response from the server :(';
+
+				alert( error );
+			}
+		} );
+	} );
+
+} );

postwriter.php

@@ -0,0 +1,265 @@
+<?php
+/*
+Plugin Name: Postwriter
+Plugin URI: http://thingalon.com/
+Description: Ghostwrites new posts automatically, based on your past posts. Useful only for comedy value.
+Version: 0.1.0
+Author: thingalon
+Author URI: http://thingalon.com
+License: GPLv2 or later
+*/
+
+// Make sure we don't expose any info if called directly
+if ( !function_exists( 'add_action' ) ) {
+	echo "Hi there!  I'm just a plugin, not much I can do when called directly.";
+	exit;
+}
+
+//	Load javascript / enqueue hook for new post submit panel
+function postwriter_enqueue_admin_scripts( $hook ) {
+	if ( 'post-new.php' == $hook ) {
+		wp_register_script( 'postwriter_admin_script', plugins_url( '/admin.js', __FILE__ ), array( 'jquery', 'jquery-ui-core', 'jquery-ui-slider' ) );
+		wp_enqueue_script( 'postwriter_admin_script' );
+
+		wp_register_style( 'postwriter_jquery_ui', plugins_url( 'postwriter/jquery-ui.min.css', __FILE ) );
+		wp_enqueue_style( 'postwriter_jquery_ui' );
+	}
+}
+add_action( 'admin_enqueue_scripts', 'postwriter_enqueue_admin_scripts' );
+
+function postwriter_add_custom_box() {
+	add_meta_box( 'postwriter_metabox', __( 'Postwriter - Generate Random', 'postwriter' ), 'postwriter_populate_custom_box', 'post', 'side', 'high' );
+}
+add_action( 'add_meta_boxes', 'postwriter_add_custom_box' );
+
+function postwriter_populate_custom_box() {
+	?>
+		<div class="misc-pub-section">
+			<div>
+				Chain by: 
+				<select id="postwriter_chain_by">
+					<option value="character">Character</option>
+					<option value="word">Word (less random)</option>
+				</select>
+			</div>
+			<div style="margin:10px 0px;">
+				Chain length:
+				<div style="display:inline-block;width:50%;margin-left:10px;position:relative;text-align:center;">
+					<div id="postwriter_chain_size"></div>
+					<span id="postwriter_chain_size_description"></span>
+				</div>
+			</div>
+			<div style="float:right">
+				<span id="postwriter_generate">
+					<a href="#" class="button button-small">Generate Post</a>
+				</span>
+				<span id="postwriter_loading" style="display:none;">
+					<img src="images/wpspin_light.gif" alt="generating..." >
+					Generating...
+				</span>
+			</div>
+			<div style="clear:both;"></div>
+		</div>
+	<?php
+}
+
+//	AJAX hook to generate and return a new post body.
+function postwriter_generate() {
+	//	Check parameters
+	$body_markov_order = isset( $_POST['chain_size'] ) ? (int)$_POST['chain_size'] : 4;
+	$body_tokenizer = ( isset( $_POST['chain_by'] ) && 'word' == $_POST['chain_by'] ) ? 'Postwriter_Word_Tokenizer' : 'Postwriter_Character_Tokenizer';
+
+	if ( $body_markov_order < 1 )
+		$body_markov_order = 1;
+	elseif ( $body_markov_order > 8 )
+		$body_markov_order = 8;
+
+	$body_length = ( 'Postwriter_Word_Tokenizer' == $body_tokenizer ) ? rand( 80, 500 ) : rand( 500, 1000 );
+
+	//	Fetch 100 random posts to use as input
+	$random_posts = get_posts( array( 'posts_per_page' => 100, 'orderby' => 'rand' ) );
+	if ( count( $random_posts ) < 10 ) {
+		//	Don't bother with less than 10 posts to work with.
+		echo json_encode( array( 'error' => 'You need at least 10 posts to meaningfully generate new posts. You seem to have only ' . count( $random_posts ) . '.' ) );
+		die();
+	}
+
+	//	Create markov chainers with randomized properties	
+	$title_markov = new Postwriter_Markov_Chainer( 'Postwriter_Character_Tokenizer', rand( 3, 5 ) );
+	$body_markov = new Postwriter_Markov_Chainer( $body_tokenizer, $body_markov_order );
+
+	//	Feed the found posts to the markov chainers
+	foreach ( $random_posts as $post ) {
+		$title_markov->feed_data( postwriter_strip_post( $post->post_title ) );
+		$body_markov->feed_data( postwriter_strip_post( $post->post_content ) );
+	}
+
+	//	Generate new post body/title
+	$new_title = $title_markov->generate_data( rand( 20, 60 ), true );
+	$new_body = $body_markov->generate_data( $body_length );
+
+	echo json_encode( array( 'title' => $new_title, 'body' => $new_body ) );
+	die();
+}
+add_action('wp_ajax_postwriter_generate', 'postwriter_generate');
+
+//	Strip the stuff we don't want to cope with out of source posts.
+function postwriter_strip_post( $post ) {
+	$post = preg_replace( '[\(\)|"]', '', $post );
+	$post = trim( preg_replace( "/<pre[^>]*>.*?<\/pre>/s", "", $post ) );
+	$post = strip_tags( $post );
+	$post = strip_shortcodes( $post );
+	return $post;
+}
+
+//	Base tokenizer class; contains behavior to generate a bunch of tokens, needs to be overridden
+class Postwriter_Tokenizer {
+	public $string;
+	public $cursor;
+
+	function Postwriter_Tokenizer( $string = null ) {
+		$this->string = $string;
+		$this->cursor = 0;
+	}
+
+	function get_n_symbols( $n ) {
+		$r = array();
+		for ( $i = 0; $i < $n; ++$i ) {
+			$s = $this->get_next_symbol();
+			if ( $s === false )
+				return $r;
+
+			$r []= $s;
+		}
+
+		return $r;
+	}
+
+	function join_symbols( $symbols ) {
+		return implode( ' ', $symbols );
+	}
+};
+
+//	Word-by-word tokenizer. Splits out words and interesting symbols into tokens of their own.
+class Postwriter_Word_Tokenizer extends Postwriter_Tokenizer {
+	function get_next_symbol() {
+		if ( $this->cursor >= strlen( $this->string ) )
+			return false;	
+
+		$sym = '';
+
+		while ( $this->cursor < strlen( $this->string ) && ( ctype_alpha( $this->string{$this->cursor} ) || ( $this->string{$this->cursor} == "'" && count( $sym ) ) ) )
+			$sym .= $this->string{$this->cursor++};
+
+		if ( empty( $sym ) ) {
+			while ( $this->cursor < strlen( $this->string ) && ctype_digit( $this->string{$this->cursor} ) )
+				$sym .= $this->string{$this->cursor++};
+
+			if ( $this->cursor < strlen( $this->string ) && empty( $sym ) )
+				$sym .= $this->string{$this->cursor++};
+		}
+
+		while ( $this->cursor < strlen( $this->string ) && ctype_space( $this->string{$this->cursor} ) )
+			$this->cursor++;
+
+		return $sym;
+	}
+
+	function join_symbols( $symbols ) {
+		$string = implode( ' ', $symbols );
+
+		//	Tidy it up a bit. 
+		$string = preg_replace( "#(\d) \. (\d)#", '$1.$2', $string );	//	Decimal place.
+		$string = preg_replace( "# ([.:,;!?]) #", "$1 ", $string );	//	Full stops, commas, etc.
+		$string = preg_replace( "# _ #", "_", $string );	//	Underscores
+
+		return $string;
+	}
+};
+
+//	Character-by-character tokenizer. Blindly splits the input into individual characters.
+class Postwriter_Character_Tokenizer extends Postwriter_Tokenizer {
+	function get_next_symbol() {
+		if ( $this->cursor >= strlen( $this->string ) )
+			return false;
+
+		return $this->string{$this->cursor++};
+	}
+
+	function join_symbols( $symbols ) {
+		return implode( '', $symbols );
+	}
+};
+
+//	Markov chainer: where the magic happens. Takes any textual input, and generates similar output.
+class Postwriter_Markov_Chainer {
+	private $table;
+	private $order;
+	private $tokenizer_class;
+
+	function Postwriter_Markov_Chainer( $tokenizer_class, $order ) {
+		error_log( $tokenizer_class );
+
+		$this->tokenizer_class = $tokenizer_class;
+		$this->order = $order;
+		$this->table = array();
+	}
+
+	//	Push data into the markov chainer, using the configured tokenizer
+	function feed_data( $input ) {
+		$tokenizer = new $this->tokenizer_class( $input );
+		$from = array();
+		$to = $tokenizer->get_n_symbols( $this->order );
+		while ( count( $to ) > 0 ) {
+			$from_key = serialize( $from );
+			$to_key = serialize( $to );
+
+			if ( ! isset( $this->table[ $from_key ] ) )
+				$this->table[ $from_key ] = array();
+			if ( ! isset( $this->table[ $from_key ][ $to_key ] ) )
+				$this->table[ $from_key ][ $to_key ] = 1;
+			else
+				$this->table[ $from_key ][ $to_key ]++;
+
+			$from = $to;
+			$to = $tokenizer->get_n_symbols( $this->order );
+		}
+	}
+
+	//	Generate $length tokens of new data.
+	function generate_data( $length, $end_on_hiccup = false ) {
+		$key = serialize( array() );
+		$data = array();
+
+		while ( count( $data ) < $length ) {
+			$next_key = null;
+			if ( isset( $this->table[ $key ] ) )
+				$next_key = $this->weighted_lookup( $this->table[ $key ] );
+
+			if ( $next_key ) {
+				$data = array_merge( $data, unserialize( $next_key ) );
+			} else {
+				if ( $end_on_hiccup )
+					break;
+
+				$next_key = serialize( array() );
+			}
+
+			$key = $next_key;
+		}
+
+		$tok = new $this->tokenizer_class();
+		return $tok->join_symbols( $data );
+	}
+
+	//	Helper method to choose the next set of tokens, by weighted roulette.
+	function weighted_lookup( $array ) {
+		$total = array_sum( $array );
+		$rand = mt_rand( 1, $total );
+		foreach ( $array as $item => $weight ) {
+			if ( $rand <= $weight )
+				return $item;
+			$rand -= $weight;
+		}
+	}
+};