<?php
// require_once(dirname(__FILE__) . '/prepend.php');
// require_once(dirname(__FILE__) . '/db.php');


// Takes a hash "$request" and extracts all key/value pairs where the keys begin with :
// The leading : is removed within the keys.
// If $remove is true, the extracted entries are deleted from the request
// Example:
//   :tablename

function decodeRequestMetaData(&$request, $remove = FALSE) {
	$result = array();
	foreach($request as $key => $value) {
		if (substr($key, 0, 1) == ':') {
			$result[substr($key, 1)] = $value;
			if ($remove) unset($request[$key]);
		}
	}
	return $result;
}


// Takes the hash "$request". The keys of its entries $key => $value are supposed
// to have the following form
// [functionname@]fieldname[:])
// If the fieldname is followed by the (optional) : this field is handled as 
// one of database key field names.
// If  the fieldname as preceded by functionname@, this function should be applied
// to the corresponding value (but this is not done within this function).
//
// Return hashes:
// $key_field_value_map: 
//   Contains key => value pairs for database keys fields
//   The database key fields are freed from the : at the end and the optional
//   functionname@ at the beginning.
// $field_value_map: The rest of the fields.
//   The fields are freed from the optional
//   functionname@ at the beginning.
// $key_function_map: A hash with all keys that have functionnames 
//   The functionnames are freed from the @ at the end
// 
// Example:
//   $request = array('id:' => 7, 'name' => 'hugo', 'md5@password' => 'abc');
//   // result:
//   $key_field_value_map == array('id' => 7)
//   $field_value_map == array('name' => 'hugo', 'password' => 'abc')
//   $key_function_map == array('password' => 'md5');

function decodeRequest($request, &$key_field_value_map, &$field_value_map, &$key_function_map) {
	// Begin with empty results
	$key_field_value_map = array();
	$field_value_map = array();
	$key_function_map = array();
	
	foreach ($request as $key => $value) {
		// Split $key in $functionname $fieldname $isdbkey
		// - Init
		$functionname = NULL;
		$fieldname = '';
		$isdbkey = FALSE;
		// - functionname
		$functionname_keyname = explode('@', $key);
		if (count($functionname_keyname) == 2) {
			$key = $functionname_keyname[1];
			$functionname = $functionname_keyname[0];
		}
		// - isdbkey
		if (substr($key, -1) == ':') {
			$key = substr($key, 0, -1);
			$isdbkey = TRUE;
		}
		// - fieldname
		$fieldname = $key;
		
		// Insert in the corresponding hashes
		if ($isdbkey) $key_field_value_map[$fieldname] = $value;
		else $field_value_map[$fieldname] = $value;
		if (!is_null($functionname)) $key_function_map[$fieldname] = $functionname;
	}
}


?>