<?php

/*
Plugin Name: Scripturizer
Plugin URL: http://scott.yang.id.au/project/phpscripturizer/
Description: Link scripture references to ESV at Good News Publisher or Bible Gateway.
Version: 1.2
Author: Scott Yang
Author URL: http://scott.yang.id.au/
*/

define('DEFAULT_SCRIPTURIZER_VERSION', 'ESV');

/**
 * Namespace for Scripturizer. 
 */
class Scripturizer {

    /**
     * Hyperlink scripture reference in text.
     *
     * @param data String containing the text.
     * @param callback A function object to be used to replace bible
     * references to hyperlinks.
     * @return Scripturized text.
     */
    function addLink($data, $callback) {
        $volumes = 'I+|1st|2nd|3rd|First|Second|Third|1|2|3';
        $books   = 'Genesis|Gen\.?|Exodus|Exod?|Ex\.?|Leviticus|Lev\.?|Levit?\.?|Numbers|Nmb\.?|'.
                   'Numb?\.?|Deuteronomy|Deut?\.?|Dt\.?|Joshua|Josh?\.?|Judges|Jdg\.?|Judg?\.?|'.
                   'Ruth|Ru\.?|Samuel|Sam\.?|Sml\.?|Kings|Kn?gs?\.?|Kin?\.?|Chronicles|Chr\.?|'.
                   'Chron\.?|Ezra|Ez\.?|Nehemiah|Nehem?\.?|Neh\.?|Esther|Esth?\.?|Job|Jb\.?|Psalms?|'.
                   'Psa?\.?|Proverbs?|Prov?\.?|Ecclesiastes|Eccl?\.?|Songs? of Solomon|'.
                   'Song?\.?|Songs|Isaiah|Isa\.?|Jeremiah|Jer\.?|Jerem\.?|Lamentations|'.
                   'Lam\.?|Lament?\.?|Ezekiel|Ezek?\.?|Daniel|Dan\.?|Hosea|Hos\.?|Joel|Jo\.|'.
                   'Amos|Am\.?|Obadiah|Obad?\.?|Jonah|Jon\.|Micah|Mic\.?|Nahum|Nah\.?|'.
                   'Habakkuk|Hab\.?|Habak|Zephaniah|Zeph\.?|Haggai|Hagg?\.?|'.
                   'Zechariah|Zech?\.?|Malachi|Malac?\.?|Mal\.?|Mat{1,2}hew|Matt?\.?|Mark|'.
                   'Mr?k\.?|Luke|Lu?k\.?|John|Jh?n\.?|Jo\.|Acts?|Ac\.?|Romans|Rom\.?|'.
                   'Corinthians|Cor\.?|Corin\.?|Galatians|Gal\.?|Galat\.?|Ephesians|Eph\.?|'.
                   'Ephes\.?|Phil+ippians|Phili?\.?|Colossians|Col\.?|Colos\.?|'.
                   'Thessalonians|Thes?\.?|Timothy|Tim\.?|Titus|Tts\.?|Tit\.?|Philemon|'.
                   'Phil?\.?|Hebrews|Hebr?\.?|James|Jam\.?|Jms\.?|Peter|Pete?\.?|Jude|Ju\.?|'.
                   'Revelations?|Rev\.?|Revel\.?';

        $verses  = '\d+(:\d+)?(?:\s?[-&]\s?\d+)?';

        return preg_replace_callback("/
            (?:($volumes)\s+)?
            ($books)
            \s+
            ($verses(?:\s?,\s?$verses)*)
            /mx",
            $callback, $data);
    }
    
    /**
     * See if the requested version is valid
     *
     * Listed below are the versions that BibleGateway supports
     *
     * @param value from the custom field
     * @return boolean
     */
    function version_exists($filter) {
    	
    	switch ($filter) {
    		case "ESV":
    		case "KJV":
    		case "NIV":
    		case "MSG":
    		case "NASB":
    		case "AMP":
    		case "NLT":
    		case "HCSB":
    		case "CEV":
    		case "NKJV":
    		case "NLV":
    		case "KJ21":
    		case "ASV":
    		case "WE":
    		case "YLT":
    		case "DARBY":
    		case "WYC":
    		case "NIRV":
    		case "NIV-UK":
					return true;
					break;
				
				default:
					return false;
				}
    
    }
    
    /**
     * Per-post filtering support. This is added as a filter hook
     * on 'the_content', so it gets called during The Loop for
     * each post displayed. We check for a post custom field
     * named 'scripture_version', and if valid, set the version
     * based on the value there.
     *
     * Logic borrowed from TFS Core (Text Filter Suite) by Dougal Campbell
     * http://dougal.gunters.org/blog/2004/08/30/text-filter-suite
     *
     * @return version
     */
		function get_version( ) {
		
		  $version = DEFAULT_SCRIPTURIZER_VERSION;
		
			$filters = get_post_custom_values('scripture_version');
			
			if (is_array($filters)) {
				foreach ($filters as $filter) {
					$filter = trim($filter);
					$filter = strtoupper($filter);
					if (Scripturizer::version_exists($filter)) {
						$version = $filter;
					} 
				}
				
			}
			
		return $version;
		}

    /**
     * Callback function for replacing scripture references in the text to
     * HTML hyperlinks.
     *
     * @param match Regex matching result array.
     * @param link URL to prepend the reference.
     * @param title Text to be used in title=".." attribute of the link.
     */
    function addLinkCallback($match, $link, $title) {
        global $_scripture_link;
        
        $vol = $match[1];
        $bok = $match[2];
        $ver = $match[3];
        $psg = htmlentities(($vol ? "$vol " : "").$bok.($ver ? " $ver" : ""));
        $ver = preg_replace(array('/:/', '/[,&;]/', '/\s*/'),
                            array('%3A', '%2C',     ''), 
                            $ver);

        $link .= ($vol ? "$vol+" : "").($bok ? "$bok+" : "").$ver;
        return "<a href=\"$link\" title=\"$title\">$psg</a>";
    }

    /**
     * Scripturize a text string. 
     *
     * @param text Original text to be scripturized.
     * @param version Translation of the scripture.
     * @return Scripturized text.
     */
    function scripturize($text, $version=0) {
        
        $version = Scripturizer::get_version();
        
        if ($version == '0')
            return $text;
 
	if (preg_match('/esv/i', $version)) {
            $title = 'English Standard Version Bible';
            $link  = 'http://www.gnpcb.org/esv/search/?go=Go&q=';
        } else {
            $title = 'Bible Gateway';
            $link  = "http://biblegateway.com/cgi-bin/bible?language=english&amp;".
                     "version=$version&amp;passage=";
        } 

        $callback = create_function('$match', "return Scripturizer::addLinkCallback(".'$match'.", '$link', '$title');");
        $text = preg_split("/(<a href.*?<\/a>|<code.*?<\/code>|<pre.*?<\/pre>|<.+?>)/ms", $text, -1, PREG_SPLIT_DELIM_CAPTURE);

        $newtext = array();
        foreach ($text as $chunk) {
            if (!preg_match('/<.*>/', $chunk)) {
                $chunk = Scripturizer::addLink($chunk, $callback);
            }
            $newtext[] = $chunk;
        }
        return implode('', $newtext);
    }
}

// If 'add_filter' function exists, then we assume that we are initialised as
// a WordPress plugin. We will try to create a new global scope function, and
// add it to filter main/comment content.
if (function_exists('add_filter')) {
    function __scripturize($content) {
        return Scripturizer::scripturize($content);
    }

    add_filter('the_content', '__scripturize');
    add_filter('comment_text', '__scripturize');
}

?>