my changes

app/Library/Xml/Field.php

@@ -0,0 +1,213 @@
+<?php
+namespace App\Library\Xml;
+
+/**
+ * Field short summary.
+ *
+ * Field description.
+ *
+ * @version 1.0
+ * @author kaiarn
+ */
+class Field
+{
+    /**
+     * Hold multiplicity constraint.
+     *
+     * @var Integer|String
+     */
+    protected $_multiplicity = 1;
+
+    /**
+     * Simple check for multiple values.
+     *
+     * @var bool
+     */
+    private $_hasMultipleValues = false;
+
+    /**
+     * Holds the classname for external fields.
+     *
+     * @var string
+     */
+    protected $_valueModelClass = null;
+
+    /**
+     * Holds the classname for link fields.
+     *
+     * @var string
+     */
+    protected $_linkModelClass = null;
+
+    /**
+     * Holds the classname of the model that the field belongs to.
+     */
+    protected $_owningModelClass = null;
+
+    /**
+     * Hold the fields value.
+     *
+     * @var mixed
+     */
+    protected $_value = null;
+
+    /**
+     * Create an new field instance and set the given name.
+     *
+     * @param string $name Internal name of the field.
+     */
+    public function __construct($name)
+    {
+        $this->_name = $name;
+    }
+
+    /**
+     * Return the name of model class if the field holds model instances.
+     *
+     * @return string Class name or null if the value is not a model.
+     */
+    public function getValueModelClass()
+    {
+        return $this->_valueModelClass;
+    }
+
+    /**
+     * Set the name of model class if the field holds model instances.
+     *
+     * @param  string $classname The name of the class that is used as model for this field or null.
+     * @return Field Fluent interface.
+     */
+    public function setValueModelClass($classname)
+    {
+        $this->_valueModelClass = $classname;
+        return $this;
+    }
+
+    public function getName()
+    {
+        return $this->_name;
+    }
+
+    /**
+     * Set the name of the model class that owns the field.
+     * @param string $classname The name of the class that owns the field.
+     * @return Field Fluent interface.
+     */
+    public function setOwningModelClass($classname)
+    {
+        $this->_owningModelClass = $classname;
+        return $this;
+    }
+
+    public function setValue($value)
+    {
+         // If the fields value is not going to change, leave.
+        if (is_object($value) === true) {
+            // weak comparison for objects
+            // TODO: DateTimeZone == DateTimeZone always returns true in weak equal check!  Why?
+            if ($value == $this->_value) {
+                return $this;
+            }
+        } else {
+            // strong comparison for other values
+            if ($value === $this->_value) {
+                return $this;
+            }
+        }
+
+        // if (true === is_array($value) and 1 === count($value)) {
+        //     //$value = array_pop($value);
+        // }
+        if (true === is_array($value) and 0 === count($value)) {
+            $value = null;
+        } elseif (is_bool($value)) {
+            // make sure 'false' is not converted to '' (empty string), but 0 for database
+            $value = (int)$value;
+        }
+
+         // if null is given, delete dependent objects
+        if (null === $value) {
+            //$this->_deleteDependentModels();
+        } else {
+            $multiValueCondition = $this->hasMultipleValues();
+            $arrayCondition = is_array($value);
+
+            // arrayfy value
+            $values = $value;
+            if (false === $arrayCondition) {
+                $values = array($value);
+            }
+            // remove wrapper array if multivalue condition is not given
+            if (false === $multiValueCondition) {
+                $value = $values[0];
+            }
+
+            $this->_value = $value;
+            return $this;
+        }
+    }
+
+    public function getValue($index = null)
+    {
+
+        // wrap start value in array if multivalue option is set for this field
+        $this->_value = $this->_wrapValueInArrayIfRequired($this->_value);
+
+        // Caller requested a specific array index
+        //if (!is_null($index)) {
+        //    if (true === is_array($this->_value)) {
+        //        if (true === isset($this->_value[$index])) {
+        //            return $this->_value[$index];
+        //        }
+        //        else {
+        //            throw new \Exception('Unvalid index: ' . $index);
+        //        }
+        //    }
+        //    else {
+        //        throw new \Exception('Invalid index (' . $index . '). Requested value is not an array.');
+        //    }
+        //}
+
+        return $this->_value;
+    }
+
+    private function _wrapValueInArrayIfRequired($value)
+    {
+        if (is_array($value) or !$this->hasMultipleValues()) {
+            return $value;
+        }
+
+        if (is_null($value)) {
+            return array();
+        }
+
+        return array($value);
+    }
+
+    public function hasMultipleValues()
+    {
+        return $this->_hasMultipleValues;
+    }
+
+    public function setMultiplicity($max)
+    {
+        if ($max !== '*') {
+            if ((is_int($max) === false) or ($max < 1)) {
+                throw new \Exception('Only integer values > 1 or "*" allowed.');
+            }
+        }
+        $this->_multiplicity = $max;
+        $this->_hasMultipleValues = (($max > 1) or ($max === '*'));
+        return $this;
+    }
+
+    /**
+     * Return the name of model class if the field holds link model instances.
+     *
+     * @return string Class name or null if the value is not a model.
+     */
+    public function getLinkModelClass()
+    {
+        return $this->_linkModelClass;
+    }
+}