Add user set timezones

Currently, aurweb displays all dates and times in UTC time. This patch
adds a capability for each logged in user to set their preferred
timezone.

Implements FS#48729.

Signed-off-by: Mark Weiman <mark.weiman@markzz.com>
Signed-off-by: Lukas Fleischer <lfleischer@archlinux.org>

1 files changed, 60 insertions, 0 deletions

diff --git a/web/lib/timezone.inc.php b/web/lib/timezone.inc.php
new file mode 100644
index 00000000..9fb24331
--- /dev/null
+++ b/web/lib/timezone.inc.php
@@ -0,0 +1,60 @@
+<?php
+set_include_path(get_include_path() . PATH_SEPARATOR . '../lib');
+
+/**
+ * Generate an associative of the PHP timezones and display text.
+ *
+ * @return array PHP Timezone => Displayed Description
+ */
+function generate_timezone_list() {
+	$php_timezones = DateTimeZone::listIdentifiers(DateTimeZone::ALL);
+
+	$offsets = array();
+	foreach ($php_timezones as $timezone) {
+		$tz = new DateTimeZone($timezone);
+		$offset = $tz->getOffset(new DateTime());
+		$offsets[$timezone] = "(UTC" . ($offset < 0 ? "-" : "+") . gmdate("H:i", abs($offset)) .
+			") " . $timezone;
+	}
+
+	asort($offsets);
+	return $offsets;
+}
+
+/**
+ * Set the timezone for the user.
+ *
+ * @return null
+ */
+function set_tz() {
+	$timezones = generate_timezone_list();
+	$update_cookie = false;
+
+	if (isset($_COOKIE["AURTZ"])) {
+		$timezone = $_COOKIE["AURTZ"];
+	} elseif (isset($_COOKIE["AURSID"])) {
+		$dbh = DB::connect();
+		$q = "SELECT Timezone FROM Users, Sessions ";
+		$q .= "WHERE Users.ID = Sessions.UsersID ";
+		$q .= "AND Sessions.SessionID = ";
+		$q .= $dbh->quote($_COOKIE["AURSID"]);
+		$result = $dbh->query($q);
+
+		if ($result) {
+			$timezone = $result->fetchColumn(0);
+		}
+
+		$update_cookie = true;
+	}
+
+	if (!isset($timezone) || !array_key_exists($timezone, $timezones)) {
+		$timezone = config_get("options", "default_timezone");
+	}
+	date_default_timezone_set($timezone);
+
+	if ($update_cookie) {
+		$timeout = intval(config_get("options", "persistent_cookie_timeout"));
+		$cookie_time = time() + $timeout;
+		setcookie("AURTZ", $timezone, $cookie_time, "/");
+	}
+}