expr.inc.php

PHP 知识管理系统（基于树结构的知识管理系统）, 英文原版的PHP源码。

<?php
/**
 * $Id:$
 *
 * KnowledgeTree Community Edition
 * Document Management Made Simple
 * Copyright (C) 2008 KnowledgeTree Inc.
 * Portions copyright The Jam Warehouse Software (Pty) Limited
 *
 * This program is free software; you can redistribute it and/or modify it under
 * the terms of the GNU General Public License version 3 as published by the
 * Free Software Foundation.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS
 * FOR A PARTICULAR PURPOSE.  See the GNU General Public License for more
 * details.
 *
 * You should have received a copy of the GNU General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 *
 * You can contact KnowledgeTree Inc., PO Box 7775 #87847, San Francisco,
 * California 94120-7775, or email [e-mail].
 *
 * The interactive user interfaces in modified source and object code versions
 * of this program must display Appropriate Legal Notices, as required under
 * Section 5 of the GNU General Public License version 3.
 *
 * In accordance with Section 7(b) of the GNU General Public License version 3,
 * these Appropriate Legal Notices must retain the display of the "Powered by
 * KnowledgeTree" logo and retain the original copyright notice. If the display of the
 * logo is not reasonably feasible for technical reasons, the Appropriate Legal Notices
 * must display the words "Powered by KnowledgeTree" and retain the original
 * copyright notice.
 * Contributor( s): ______________________________________
 *
 */

//require_once('../../config/dmsDefaults.php');

/**
 * This is the ideal case, but more complex
 *
 */

// TODO: search expression evaluation needs some optimisation

require_once('indexing/indexerCore.inc.php');
require_once('search/fieldRegistry.inc.php');
require_once('search/exprConstants.inc.php');

class RankManager
{
	/**
	 * This array contains the rankings of fields on database tables.
	 *
	 * @var array
	 */
	private $db;
	/**
	 * Contains the rankings of metadata fields on fieldset/field combinations.
	 *
	 * @var array
	 */
	private $metadata;
	/**
	 * Contains ranking factor for discussion matching
	 *
	 * @var float
	 */
	private $discussion;
	/**
	 * Contains the ranking factor for text matching
	 *
	 * @var float
	 */
	private $text;

	private function __construct()
	{
		$this->dbfields=array();
		$sql = "SELECT groupname, itemname, ranking, type FROM search_ranking";
		$rs = DBUtil::getResultArray($sql);
		foreach($rs as $item)
		{
			switch ($item['type'])
			{
				case 'T':
					$this->db[$item['groupname']][$item['itemname']] = $item['ranking']+0;
					break;
				case 'M':
					$this->metadata[$item['groupname']][$item['itemname']] = $item['ranking']+0;
					break;
				case 'S':
					switch($item['groupname'])
					{
						case 'Discussion':
							$this->discussion = $item['ranking']+0;
							break;
						case 'DocumentText':
							$this->text = $item['ranking']+0;
							break;
					}
					break;
			}
		}
	}

	/**
	 * Enter description here...
	 *
	 * @return RankManager
	 */
	public static function get()
	{
		static $singleton = null;
		if (is_null($singleton))
		{
			$singleton = new RankManager();
		}
		return $singleton;
	}

	public function scoreField($groupname, $type='T', $itemname='')
	{
		switch($type)
		{
			case 'T':
				return $this->db[$groupname][$itemname];
			case 'M':
				return $this->metadata[$groupname][$itemname];
			case 'S':
				switch($groupname)
				{
					case 'Discussion':
						return $this->discussion;
					case 'DocumentText':
						return $this->text;
					default:
						return 0;
				}
			default:
				return 0;
		}
	}
}


class Expr
{
    /**
     * The parent expression
     *
     * @var Expr
     */
    protected $parent;

    protected static $node_id = 0;

    protected $expr_id;

    protected $context;

    public function __construct()
    {
        $this->expr_id = Expr::$node_id++;
    }

    public function appliesToContext()
    {
        return ExprContext::DOCUMENT;
    }

    public function setContext($context)
    {
        $this->context = $context;
    }

    public function getContext()
    {
        return $this->context;
    }

    public function getExprId()
    {
        return $this->expr_id;
    }

    /**
     * Coverts the expression to a string
     *
     * @return string
     */
    public function __toString()
    {
        throw new Exception(sprintf(_kt('Not yet implemented in %s'), get_class($this)));
    }

    /**
     * Reference to the parent expression
     *
     * @return Expr
     */
    public function &getParent()
    {
        return $this->parent;
    }

    /**
     * Sets the parent expiression
     *
     * @param Expr $parent
     */
    public function setParent(&$parent)
    {
        $this->parent = &$parent;
    }

    /**
     * Is the expression valid
     *
     * @return boolean
     */
    public function is_valid()
    {
        return true;
    }

    public function isExpr()
    {
    	return $this instanceof OpExpr;
    }

    public function isOpExpr()
    {
    	return $this instanceof OpExpr;
    }
    public function isValueExpr()
    {
    	return $this instanceof ValueExpr;
    }
    public function isValueListExpr()
    {
    	return $this instanceof ValueListExpr;
    }

    public function isDbExpr()
    {
    	return $this instanceof DBFieldExpr;
    }

    public function isFieldExpr()
    {
    	return $this instanceof FieldExpr;
    }

    public function isSearchableText()
    {
    	return $this instanceof SearchableText ;
    }

    public function isMetadataField()
    {
    	return $this instanceof MetadataField;
    }





    public function toViz(&$str, $phase)
    {
        throw new Exception('To be implemented' . get_class($this));
    }

    public function toVizGraph($options=array())
    {
        $str = "digraph tree {\n";
        if (isset($options['left-to-right']) && $options['left-to-right'])
        {
            $str .= "rankdir=LR\n";
        }

        $this->toViz($str, 0);
        $this->toViz($str, 1);

        $str .= "}\n";

        if (isset($options['tofile']))
        {
            $path=dirname($options['tofile']);
            $filename=basename($options['tofile']);
            $ext = pathinfo($filename, PATHINFO_EXTENSION);
            $base = substr($filename, 0, -strlen($ext)-1);

            $curdir = getcwd();
            chdir($_ENV['PWD']);
            $dotfile="$base.$ext";
            $jpgfile="$base.jpg";
            $fp = fopen($dotfile,'wt');
            fwrite($fp, $str);
            fclose($fp);

            system("dot -Tjpg -o$jpgfile $dotfile 2>1 >/dev/null ");

            if (isset($options['view']) && $options['view'])
            {
                system("eog $jpgfile");
            }
            chdir($curdir);
        }

        return $str;
    }
}

class FieldExpr extends Expr
{
    /**
     * Name of the field
     *
     * @var string
     */
    protected $field;

    protected $alias;

    protected $display;


    /**
     * Constructor for the field expression
     *
     * @param string $field
     */
    public function __construct($field, $display=null)
    {
        parent::__construct();
        $this->field=$field;
        if (is_null($display))
        {
        	$display=get_class($this);
        }
        $this->display = $display;
        $this->setAlias(get_class($this));
    }

    public function setAlias($alias)
    {
        $this->alias=$alias;
    }

    public function getDisplay()
    {
    	return $this->display;
    }

    public function getAlias()
    {
        return $this->alias;
    }

    public function getFullName()
    {
        return $this->alias . '.' . $this->field;
    }

    /**
     * Returns the field
     *
     * @return string
     */
    public function getField()
    {
        return $this->field;
    }

    /**
     * Coverts the expression to a string
     *
     * @return string
     */
    public function __toString()
    {
        return $this->display;
    }

    public function toViz(&$str, $phase)
    {
        if ($phase == 0)
        {
            $expr_id = $this->getExprId();
            $str .= "struct$expr_id [style=rounded, label=\"$expr_id: FIELD[$this->alias]\"]\n";
        }
    }

    public function rewrite(&$left, &$op, &$right, $not=false)
    {
    	$input = $left->getInputRequirements();

		if ($input['value']['type'] != FieldInputType::FULLTEXT)
		{
			return;
		}


    	if ($right->isValueExpr())
		{
			$value = $right->getValue();
		}
		else
		{
			$value = $right;
		}

		if ((substr($value,0,1) == '\'' && substr($value,-1) == '\'') || (substr($value,0,1) == '"' && substr($value,-1) == '"'))
		{
			$value =  trim( substr($value,1,-1) );
			$right = new ValueExpr($value);
		}
		else
		{
			OpExpr::rewriteString($left, $op, $right, $not);
		}
    }
}

class ExprContext
{
    const DOCUMENT = 1;
    const FOLDER = 2;
    const DOCUMENT_AND_FOLDER = 3;
}


class DBFieldExpr extends FieldExpr
{
    /**
     * The table the field is associated with
     *
     * @var string
     */
    protected $table;

    protected $jointable;
    protected $joinfield;
    protected $matchfield;
    protected $quotedvalue;


    /**
     * Constructor for the database field
     *
     * @param string $field
     * @param string $table
     */
    public function __construct($field, $table, $display=null)
    {
    	if (is_null($display))
    	{
    		$display = get_class($this);
    	}

        parent::__construct($field, $display);

        $this->table=$table;
        $this->jointable = null;
        $this->joinfield = null;
        $this->matchfield = null;
        $this->quotedvalue=true;
    }

    /**
     * Returns the table name
     *
     * @return string
     */
    public function getTable()
    {
        return $this->table;
    }

    public function joinTo($table, $field)
    {
    	$this->jointable=$table;
    	$this->joinfield=$field;
    }
    public function matchField($field)
    {
    	$this->matchfield = $field;
    }

	public function modifyName($name)
    {
    	return $name;
    }

	public function modifyValue($value)
    {
    	return $value;
    }


    public function getJoinTable() { return $this->jointable; }
    public function getJoinField() { return $this->joinfield; }
    public function getMatchingField() { return $this->matchfield; }
    public function isValueQuoted($quotedvalue = null)
    {
    	if (isset($quotedvalue))
    	{
    		$this->quotedvalue = $quotedvalue;
    	}
    	return $this->quotedvalue;
    }
}

class MetadataField extends DBFieldExpr
{
    protected $fieldset;
    protected $fieldid;
    protected $fieldsetid;

    public function __construct($fieldset, $field, $fieldsetid, $fieldid)
    {
        parent::__construct($field, 'document_fields_link');
        $this->fieldset=$fieldset;
        $this->fieldid=$fieldid;
        $this->fieldsetid=$fieldsetid;
    }

    public function getFieldSet()
    {
        return $this->fieldset;
    }

    public function getFieldId()
    {
        return $this->fieldid;
    }

    public function getFieldSetId()
    {
        return $this->fieldsetid;
    }

    public function getInputRequirements()
    {
        return array('value'=>array('type'=>FieldInputType::TEXT));
    }

    /**
     * Coverts the expression to a string
     *
     * @return string
     */
    public function __toString()
    {
        return "METADATA[$this->fieldset][$this->field]";
    }

}

class SearchableText extends FieldExpr
{
}

class ValueExpr extends Expr
{
    /**
     * The value
     *
     * @var mixed
     */
    protected $value;

    protected $fuzzy;

    protected $proximity;

    /**
     * Constructor for the value expression
     *
     * @param mixed $value
     */
    public function __construct($value, $fuzzy=null, $proximity=null)
    {
        parent::__construct();

        // some keywords are used by lucene, and may conflict. for some reason, if it is lowercase, the problem does not occur.