1 files changed, 74 insertions, 0 deletions
diff --git a/includes/sys_page.php b/includes/sys_page.php
index 6863c517..67da83c7 100644
--- a/includes/sys_page.php
+++ b/includes/sys_page.php
@@ -19,6 +19,46 @@ function raw_output($output) {
 }
 
 /**
+ * Checks if given request item (name) can be parsed to a date.
+ * If not parsable, given error message is put into msg() and null is returned.
+ *
+ * @param string $input
+ *          String to be parsed into a date.
+ * @param string $error_message
+ *          the error message displayed if $input is not parsable
+ * @param boolean $null_allowed
+ *          is a null value allowed?
+ * @return ValidationResult containing the parsed date
+ */
+function check_request_date($name, $error_message = null, $null_allowed = false) {
+  if (! isset($_REQUEST[$name]))
+    return new ValidationResult($null_allowed, null);
+  return check_date($_REQUEST[$name], $error_message, $null_allowed);
+}
+
+/**
+ * Checks if given string can be parsed to a date.
+ * If not parsable, given error message is put into msg() and null is returned.
+ *
+ * @param string $input
+ *          String to be parsed into a date.
+ * @param string $error_message
+ *          the error message displayed if $input is not parsable
+ * @param boolean $null_allowed
+ *          is a null value allowed?
+ * @return ValidationResult containing the parsed date
+ */
+function check_date($input, $error_message = null, $null_allowed = false) {
+  if (DateTime::createFromFormat("Y-m-d", trim($input)))
+    return new ValidationResult(true, DateTime::createFromFormat("Y-m-d", trim($input)));
+  if ($null_allowed)
+    return new ValidationResult(true, null);
+  
+  error($error_message);
+  return new ValidationResult(false, null);
+}
+
+/**
  * Gibt den gefilterten REQUEST Wert ohne Zeilenumbrüche zurück
  */
 function strip_request_item($name) {
@@ -57,4 +97,38 @@ function check_email($email) {
   return (bool) filter_var($email, FILTER_VALIDATE_EMAIL);
 }
 
+class ValidationResult {
+
+  private $ok;
+
+  private $value;
+
+  /**
+   * Constructor.
+   *
+   * @param boolean $ok
+   *          Is the value valid?
+   * @param * $value
+   *          The validated value
+   */
+  public function ValidationResult($ok, $value) {
+    $this->ok = $ok;
+    $this->value = $value;
+  }
+
+  /**
+   * Is the value valid?
+   */
+  public function isOk() {
+    return $this->ok;
+  }
+
+  /**
+   * The parsed/validated value.
+   */
+  public function getValue() {
+    return $this->value;
+  }
+}
+
 ?>