<?php
require_once($INC . "/sql.inc.php");
require_once($INC . "/cache.inc.php");
require_once($INC . "/prof.inc.php");

$rg_state_error = "";

if (!isset($rg_state_debug))
	$rg_state_debug = FALSE;

function rg_state_set_error($str)
{
	global $rg_state_error;
	$rg_state_error = $str;
	rg_log($str);
}

function rg_state_error()
{
	global $rg_state_error;
	return $rg_state_error;
}

/*
 * Get state
 */
function rg_state_get($db, $var)
{
	global $rg_state_debug;

	rg_prof_start("state_get");
	if ($rg_state_debug)
		rg_log_enter("state_get: var=$var");

	$ret = FALSE;
	while (1) {
		// Try cache first
		$r = rg_cache_get("state::" . $var);
		if ($r !== FALSE) {
			$ret = $r;
			break;
		}

		// Not found in cache, try the database
		$params = array("var" => $var);
		$sql = "SELECT value FROM state WHERE var = @@var@@ LIMIT 1";
		$res = rg_sql_query_params($db, $sql, $params);
		if ($res === FALSE) {
			rg_state_set_error(rg_sql_error());
			break;
		}

		$rows = rg_sql_num_rows($res);
		if ($rows == 0) {
			$ret = "";
		} else {
			$row = rg_sql_fetch_array($res);
			$ret = $row['value'];
			rg_cache_set("state::" . $var, $ret, RG_SOCKET_NO_WAIT);
		}
		rg_sql_free_result($res);

		break;
	}

	if ($rg_state_debug)
		rg_log_exit();
	rg_prof_end("state_get");
	return $ret;
}

/*
 * Return a state as uint
 */
function rg_state_get_uint($db, $var)
{
	$r = rg_state_get($db, $var);
	if ($r === FALSE)
		return FALSE;

	return intval($r);
}

/*
 * Set state
 */
function rg_state_set($db, $var, $value)
{
	global $rg_state_debug;

	rg_prof_start("state_set");
	if ($rg_state_debug)
		rg_log_enter("state_set: $var = $value");

	$ret = FALSE;
	while (1) {
		$params = array("var" => $var, "value" => $value);
		$old = rg_state_get($db, $var);
		if ($old === FALSE)
			break;

		if (strcmp($old, $value) == 0)
			return TRUE;

		$sql = 'UPDATE state SET value = @@value@@'
			. ' WHERE var = @@var@@';
		$res = rg_sql_query_params($db, $sql, $params);
		if ($res === FALSE) {
			rg_state_set_error('cannot update var');
			break;
		}
		$rows = rg_sql_affected_rows($res);
		rg_sql_free_result($res);

		if ($rows == 0) {
			$sql = 'INSERT INTO state (var, value)'
				. ' VALUES (@@var@@, @@value@@)';
			$res = rg_sql_query_params($db, $sql, $params);
			if ($res === FALSE) {
				rg_state_set_error('cannot insert into state table');
				break;
			}
			rg_sql_free_result($res);
		}

		rg_cache_set("state::" . $var, $value, RG_SOCKET_NO_WAIT);

		$ret = TRUE;
		break;
	}

	if ($rg_state_debug)
		rg_log_exit();
	rg_prof_end("state_set");
	return $ret;
}

?>