<?php

class SkayoDB{
	public $config;
	public function __construct(){
	$this->config = array(
		'debug' => True,
		'DB_dir' => 'DB',
		);
	if($this->config["debug"]){error_reporting(E_ALL);};
	}
//-----------------------------------------------------------------

	/**
	 *  Call once to create the DB-Folder and a htaccess-File
	 *  @returns null
	 */
	function setup(){
		if(!file_exists($this->config["DB_dir"])){
			mkdir($this->config["DB_dir"]);
		}
			if(!file_exists($this->config["DB_dir"]."/.htaccess")){
			$handle = fopen($this->config["DB_dir"]."/.htaccess", "w");
			fwrite($handle, '<Files ~ "\.xml$">
Order deny,allow
Deny from all
</Files>');
			fclose($handle);
		}
	}

	/**
	 *  Creates a new databank
	 *  @param   string $name The name of the databank
	 *  @returns string       If debug is true, it returns a message
	 */
	function createDB($name){
		if(is_writable($this->config["DB_dir"]) && !file_exists($this->config["DB_dir"]."/".$name.".xml")){
			$handle = fopen($this->config["DB_dir"]."/".$name.".xml", "w");
			fwrite($handle, '<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
<databank>
	<'.$name.'>
	</'.$name.'>
</databank>');
			fclose($handle);
			if(file_exists($this->config["DB_dir"]."/".$name.".xml")){
				if($this->config["debug"]){
				return "Done";
				}
			} else {
				if($this->config["debug"]){
				return "Databank couldn't be created! Please check.";
				}
			}
		} else {
			if($this->config["debug"]){
			return "Databank-Dir is not writeable or file already exists! Please check.";
			}
		}
	}

	/**
	 *  Used to create a new XML-Node
	 *  @param   string  $DBname         The name of the database you want to use
	 *  @param   string  $content        The content you want to store in that node
	 *  @param   string  $elementname    The name of the node you want to create
	 *  @param   string  $parent         The name of the parent wich you want to create a child from
	 *  @param   integer $parentnum      If you have more than one parent of a name, you can choose the number of the parent you want to use
	 *  @param   string  $attributename  The name of the attribute, if you want to have an attribute for the node
	 *  @param   string  $attributevalue The value of the attribute, if you want to have an attribute for the node
	 *  @returns string                  If debug is true, it returns a message
	 */
	function newXMLelement($DBname, $content, $elementname, $parent, $parentnum = 0, $attributename = NULL, $attributevalue = NULL){
		if(file_exists($this->config["DB_dir"]."/".$DBname.".xml")){
			$doc = new DOMDocument();
			$xpath = new DOMXPath($doc);
			$doc->load($this->config["DB_dir"]."/".$DBname.".xml");
			$parents = $doc->getElementsByTagName($parent)->item($parentnum);
			if($parents == NULL){
				if($this->config["debug"]){
					return "Element not found! Please check";
				}
			} else {
				$element = $doc->createElement($elementname, $content);
				if($attributename !== NULL && $attributevalue !== NULL){
					$attribute = $doc->createAttribute($attributename);
					$attribute->value = $attributevalue;
					$element->appendChild($attribute);
				}
				$parents->appendChild($element);
				$doc->save($doc->documentURI);
				if($this->config["debug"]){
					return "Done";
				}
			}
		} else {
			if($this->config["debug"]){
				return "Databank does not exits! Please check.";
			}
		}
	}

	/**
	 *  Used to update the value of an existing node.
	 *  @param   string  $DBname      The name of the database you want to use
	 *  @param   string  $newValue    The new value you want to store
	 *  @param   string  $elementname The name of the node you want to update
	 *  @param   integer $elementnum  If you have more than one nodes of a name, you can choose the number of the node you want to update
	 *  @returns string               If debug is true, it returns a message
	 */
	function updateXMLvalue($DBname, $newValue, $elementname, $elementnum = 0){
		$doc = new DOMDocument();
		$xpath = new DOMXPath($doc);
		$doc->load($this->config["DB_dir"]."/".$DBname.".xml");
		$newElement = $doc->getElementsByTagName($elementname)->item($elementnum);
		if($newElement == NULL){
			if($this->config["debug"]){
				return "Element not found! Please check";
			}
		} else {
			$newElement->nodeValue = $newValue;
			$doc->save($doc->documentURI);
			if($this->config["debug"]){
				return "Done";
			}
		}
	}

	/**
	 *  Used to get the value of an existing node
	 *  @param   string  $DBname         The name of the database you want to use
	 *  @param   string  $mode           The mode you want to use. You can choose between value (to get the value), number (to get the number of an node) and count (to get the number of existing nodes)
	 *  @param   string  $elementname    The name of the node you want to get the information from
	 *  @param   integer $elementnum     If you have more than one nodes of a name, you can choose the number of the node you want to get the information from
	 *  @param   string  $attributename  The name of the attribute you want to get the value from
	 *  @param   string  $attributevalue The value of the attribute you want to get the value from
	 *  @returns string                  If debug is true, it returns a message
	 */
	function getXML($DBname, $mode, $elementname, $elementnum = 0, $attributename = NULL, $attributevalue = NULL){
		$doc = new DOMDocument();
		$xpath = new DOMXPath($doc);
		$doc->load($this->config["DB_dir"]."/".$DBname.".xml");
		if($mode == "value"){
			if($attributename !== NULL && $attributevalue !== NULL){
				$search = $doc->getElementsByTagName($elementname);
				if($search == NULL){
					if($this->config["debug"]){
						return "Element not found! Please check";
					}
				} else {
					foreach ($search as $node) {
						if($node->getAttribute($attributename) == $attributevalue){
							$found = $node->nodeValue;
							if($found == NULL or $found == ""){
								if($this->config["debug"]){
									return "Element has no value! Please check.";
								}
							} else {
								return $found;
							}
						}
					}
				}
			} else {
				$search = $doc->getElementsByTagName($elementname)->item($elementnum);
				if($search == NULL){
					if($this->config["debug"]){
						return "Element not found! Please check";
					}
				} else {
					$found = $search->nodeValue;
					if($found == NULL or $found == ""){
						if($this->config["debug"]){
							return "Element has no value! Please check.";
						}
					} else {
						return $found;
					}	
				}
			}
		} elseif ($mode == "number" && $attributename !== NULL && $attributevalue !== NULL){
			$search = $doc->getElementsByTagName($elementname);
			if($search == NULL){
					if($this->config["debug"]){
						return "Element not found! Please check";
					}
			} else {
				$count = 0;
				foreach ($search as $node) {
					$count++;
					if($node->getAttribute($attributename) == $attributevalue){
						return $count;
					}
				}
			}
		} elseif ($mode == "count") {
			if($attributename !== NULL && $attributevalue !== NULL){
				$search = $doc->getElementsByTagName($elementname);
				if($search == NULL){
					if($this->config["debug"]){
						return "Element not found! Please check";
					}
				} else {
					$count = 0;
					foreach ($search as $node) {
						if($node->getAttribute($attributename) == $attributevalue){
							$count++;
						}
					}
					return $count;
				}
			} else {
				$search = $doc->getElementsByTagName($elementname);
				$count = 0;
				foreach ($search as $node) {
					$count++;
				}
				return $count;
			}
		}
	}

	/**
	 *  Used to remove an existing node
	 *  @param   string  $DBname      The name of the database you want to use
	 *  @param   string  $parentname  The name of the parent you want to delete a child from
	 *  @param   integer $parentnum   The number of the parent you want to delete a child from
	 *  @param   string  $elementname The name of the node you want to delete
	 *  @param   integer $elementnum  The number of the node you want to delete
	 *  @returns string               If debug is true, it returns a message
	 */
	function removeXMLnode($DBname, $parentname, $parentnum = 0, $elementname, $elementnum = 0){
		$doc = new DOMDocument();
		$xpath = new DOMXPath($doc);
		$doc->load($this->config["DB_dir"]."/".$DBname.".xml");
		$parent = $doc->getElementsByTagName($parentname)->item($parentnum);
		$del = $parent->getElementsByTagName($elementname)->item($elementnum);
		if($parent == NULL || $del == NULL){
			if($this->config["debug"]){
				return "Could not find Node with the given parentname or elementname! Please check.";
			}
		} else {
			$parent->removeChild($del);
			$doc->save($doc->documentURI);
			if($this->config["debug"]){
				return "Done";
			}
		}
	}
}
?>