<?php

/**
 * Search Engine : Search through all types of databap documents
 *
 * Procedure to add a new type in the search
 * - Add type in Databap->getItemTables()
 * - Add type in the index builder : SearchEngine->buildIndex()
 * - Add type in item info : SearchEngine->setItemInfo()
 * - Add type in Databap->getItemList() and create a Databap->get<type>info()
 * - Add type text in Databap->getProfile()
 * - Consider the message types : add + edit in Databap->getMessages() and in chat.html
 */
class SearchEngine extends PhpObject
{
	//Objects
	private $oMySql;

	//variables
	private $asWords;
	private $iLevelMax;
	private $asItemRanks;
	private $asItemInfos;
	private $asUserInfos;

	//Constants
	const RESULT_A_PAGE = 20;
	const KEYWORDS_SEPARATOR = ' ';

	function __construct($oMySql)
	{
		parent::__construct(__CLASS__, Settings::DEBUG);
		$this->oMySql = $oMySql;
		$this->asWords = $this->setWords('');
		$this->asItemRanks = array();
		$this->asItemInfos = array();
		$this->asUserInfos = array();
	}

	public function buildIndex($iItemId, $sType)
	{
		//Build keywords
		switch($sType)
		{
			case Databap::CODE_TYPE:
				$asItemData = $this->oMySql->selectRow(Databap::CODE_TABLE, $iItemId);
				$asWords = array($asItemData[MySqlManager::getText(Databap::CODE_TABLE)], $asItemData['description']);
				break;
			case Databap::PROC_TYPE:
				$sItemIdCol = MySqlManager::getId(Databap::PROC_TABLE);
				$asItemData = $this->oMySql->selectRow(Databap::PROC_TABLE, $iItemId);
				$asItemStepsData = $this->oMySql->selectRows(array('select'=>'description', 'from'=>Databap::STEP_TABLE, 'constraint'=>array($sItemIdCol=>$iItemId)));
				$asWords = array('desc'=>$asItemData['description'], 'title'=>$asItemData['title']) + $asItemStepsData;
				break;
			case Databap::ART_TYPE:
				$asItemData = $this->oMySql->selectRow(Databap::ART_TABLE, $iItemId);
				$asWords = array($asItemData['first_name'], $asItemData['last_name'], $asItemData['title']);
				break;
			case Databap::DOC_TYPE:
				$sItemIdCol = MySqlManager::getId(Databap::DOC_TABLE);
				$asItemData = $this->oMySql->selectRow(Databap::DOC_TABLE, $iItemId);
				$asItemFilesData = $this->oMySql->selectRows(array('select'=>'description', 'from'=>Databap::FILE_TABLE, 'constraint'=>array($sItemIdCol=>$iItemId)));
				$asWords = array('desc'=>$asItemData['description'], 'title'=>$asItemData['title']) + $asItemFilesData;
				break;
			case Databap::TABLE_TYPE:
				$asItemData = $this->oMySql->selectRow(Databap::TABL_TABLE, $iItemId);
				$asWords = array('desc'=>$asItemData['description'], 'title'=>$asItemData['title'], 'keywords'=>$asItemData['keywords'], 'system'=>$asItemData['system']);
				break;
			default:
				$this->addError('function '.__FUNCTION__.'(): Incorrect type "'.$sType.'"');
				break;
		}
		$sWords = implode(self::KEYWORDS_SEPARATOR, $asWords);
		$sWords = mb_strtolower(str_replace("\n", self::KEYWORDS_SEPARATOR, $sWords));
		$sWords = preg_replace('/(\W+)/u', self::KEYWORDS_SEPARATOR, $sWords); //remove all non-word characters

		//Add / Modify search database
		$asData = array('id_item'=>$iItemId, 'type'=>$sType, 'refer_id'=>(array_key_exists('refer_id', $asItemData)?$asItemData['refer_id']:$iItemId), 'keywords'=>$sWords);
		$this->oMySql->insertUpdateRow(Databap::SEARCH_TABLE, $asData, array('id_item', 'type'));
	}

	public function setWords($sSearchWords)
	{
		$this->asWords = $this->getParsedWords($sSearchWords);
		$this->iLevelMax = count($this->asWords);
		$this->setResults();
	}

	/**
	 * TODO Customized item preview
		$sCodeLines = implode("\n...\n", $this->getCodeInfo($iItemId, 'code'));
		$oCode = new Reader($sCodeLines);
		$sCodeLines = $oCode->getColoredCode();
	 */
	private function setItemInfo($iSearchId, $iItemType, $iItemId)
	{
		if(!array_key_exists($iSearchId, $this->asItemInfos))
		{
			/*switch($iItemType)
			{
				case Databap::CODE_TYPE:
					$sItemTable = Databap::CODE_TABLE;
					$asItemFields = array(MySqlManager::getId(Databap::USER_TABLE), 'description', 'led');
					break;
				case Databap::PROC_TYPE:
					$sItemTable = Databap::PROC_TABLE;
					$asItemFields = array(MySqlManager::getId(Databap::USER_TABLE), 'title AS description', 'led');
					break;
				case Databap::ART_TYPE:
					$sItemTable = Databap::ART_TABLE;
					$asItemFields = array('first_name', 'last_name', 'title AS description', 'led');
					break;
				case Databap::DOC_TYPE:
					$sItemTable = Databap::DOC_TABLE;
					$asItemFields = array(MySqlManager::getId(Databap::USER_TABLE), 'title AS description', 'led');
					break;
				case Databap::TABLE_TYPE:
					$sItemTable = Databap::TABL_TABLE;
					$asItemFields = array(MySqlManager::getId(Databap::USER_TABLE), 'title AS description', 'led');
					break;
			}
			$this->asItemInfos[$iSearchId] = $this->oMySql->selectRow($sItemTable, $iItemId, $asItemFields);*/
			$this->asItemInfos[$iSearchId]['type'] = $iItemType;
			$this->asItemInfos[$iSearchId]['id_item'] = $iItemId;
		}
	}

	private function getItemInfo($iSearchId, $sInfoName)
	{
		if(array_key_exists($iSearchId, $this->asItemInfos) && array_key_exists($sInfoName, $this->asItemInfos[$iSearchId]))
			return $this->asItemInfos[$iSearchId][$sInfoName];
		else return false;
	}

	/*
	private function setUserInfo($iUserId)
	{
		if($iUserId > 0 && !array_key_exists($iUserId, $this->asUserInfos))
		{
			$sCompanyIdCol = MySqlManager::getId(Databap::COMP_TABLE);
			$this->asUserInfos[$iUserId] = $this->oMySql->selectRow
			(
					Databap::USER_TABLE,
					$iUserId,
					array('first_name', 'last_name', $sCompanyIdCol)
			);

			$this->asUserInfos[$iUserId]['company'] = $this->oMySql->selectValue(Databap::COMP_TABLE, MySqlManager::getText(Databap::COMP_TABLE), $this->asUserInfos[$iUserId][$sCompanyIdCol]);
			unset($this->asUserInfos[$iUserId][$sCompanyIdCol]);
		}
	}

	private function getUserInfo($iUserId, $sInfoName)
	{
		if(array_key_exists($iUserId, $this->asUserInfos) && array_key_exists($sInfoName, $this->asUserInfos[$iUserId]))
			return $this->asUserInfos[$iUserId][$sInfoName];
		else return false;
	}
	*/

	private function setResults()
	{
		if($this->iLevelMax > 0)
		{
			//set Results and Ranking
			$aiLevels = range(1, $this->iLevelMax);
			arsort($aiLevels);
			foreach($aiLevels as $iLevel)
			{
				//all possibilies at level $iLevel
				$iIndex = 0;
				while(($iIndex + $iLevel) <= $this->iLevelMax)
				{
					//building query
					$asSequence = array_slice($this->asWords, $iIndex, $iLevel);
					$this->oMySql->cleanSql($asSequence);

					//$sRegExp = implode('(.{0,2})', $asSequence);
					$sRegExp = implode(self::KEYWORDS_SEPARATOR.'?', $asSequence);
					$sSequence = implode(self::KEYWORDS_SEPARATOR, $asSequence);

					//TODO replace with selectRow()
					$sQuery = "SELECT id_search, MAX(id_item) AS id_item, type, keywords FROM searchs WHERE keywords REGEXP '{$sRegExp}' GROUP BY type, refer_id";

					//search sequence
					$asItems = $this->oMySql->getArrayQuery($sQuery, true);
					foreach($asItems as $asItem)
					{
						$iSearchId = $asItem['id_search'];
						$iItemId = $asItem['id_item'];;
						$iItemType = $asItem['type'];
						$sWords = $asItem['keywords'];

						//Calculate bonus points
						$sWords = str_replace(self::KEYWORDS_SEPARATOR.$sSequence.self::KEYWORDS_SEPARATOR,	self::KEYWORDS_SEPARATOR, self::KEYWORDS_SEPARATOR.$sWords.self::KEYWORDS_SEPARATOR, $iSeqCount);
						$sWords = str_replace(self::KEYWORDS_SEPARATOR.$sSequence,							self::KEYWORDS_SEPARATOR, self::KEYWORDS_SEPARATOR.$sWords.self::KEYWORDS_SEPARATOR, $iStaCount);
						$sWords = str_replace($sSequence.self::KEYWORDS_SEPARATOR,							self::KEYWORDS_SEPARATOR, self::KEYWORDS_SEPARATOR.$sWords.self::KEYWORDS_SEPARATOR, $iEndCount);
						$iBonus = $iSeqCount*5 + $iStaCount*2 + $iEndCount;

						$this->incItemRank($iSearchId, $iLevel*10+$iBonus);
						$this->setItemInfo($iSearchId, $iItemType, $iItemId);
						//$this->setUserInfo($this->getItemInfo($iSearchId, MySqlManager::getId(Databap::USER_TABLE)));
					}
					$iIndex++;
				}
			}
		}
	}

	public function getResults()
	{
		$asResult = array();

		//Mixing info
		arsort($this->asItemRanks);
		foreach($this->asItemRanks as $iSearchId=>$iRank)
		{
			/*$iUserId = $this->getItemInfo($iSearchId, MySqlManager::getId(Databap::USER_TABLE));
			$sFirstName = $this->getUserInfo($iUserId, 'first_name')?$this->getUserInfo($iUserId, 'first_name'):$this->getItemInfo($iSearchId, 'first_name');
			$sLastName = $this->getUserInfo($iUserId, 'last_name')?$this->getUserInfo($iUserId, 'last_name'):$this->getItemInfo($iSearchId, 'last_name');
			$sCompany = $this->getUserInfo($iUserId, 'company')?$this->getUserInfo($iUserId, 'company'):'SAP';
			$asResult[] = array('id_item'=>$this->getItemInfo($iSearchId, 'id_item'),
								'type'=>$this->getItemInfo($iSearchId, 'type'),
								'description'=>$this->getItemInfo($iSearchId, 'description'),
								'rank'=>$iRank,
								'name'=>Databap::getNameFormat($sFirstName, $sLastName),
								'company'=>Databap::getCompanyFormat($sCompany),
								'led'=>Databap::getDateFormat($this->getItemInfo($iSearchId, 'led')));
			*/
			$asResult[] = array('id_item'=>$this->getItemInfo($iSearchId, 'id_item'),
								'type'=>$this->getItemInfo($iSearchId, 'type'),
								'rank'=>$iRank);
		}
		return $asResult;
	}

	private function incItemRank($iSearchId, $iRank)
	{
		if(array_key_exists($iSearchId, $this->asItemRanks))
		{
			$this->asItemRanks[$iSearchId] += $iRank;
		}
		else
		{
			$this->asItemRanks[$iSearchId] = $iRank;
		}
	}

	private function getParsedWords($sSearchWords)
	{
		return array_unique(array_filter(explode(' ', $sSearchWords), array($this, 'checkSearchedWords')));
	}

	private function checkSearchedWords($sWord)
	{
		return (mb_strlen($sWord) >= 2);
	}
}

?>