[UPDATE] initialization of fields and handling of expressions

src/Field.php

@@ -9,6 +9,7 @@
 use atk4\core\TrackableTrait;
 use atk4\dsql\Expression;
 use atk4\dsql\Expressionable;
+use atk4\core\InitializerTrait;
 
 /**
  * Class description?
@@ -18,6 +19,9 @@ class Field implements Expressionable
     use TrackableTrait;
     use DIContainerTrait;
     use ReadableCaptionTrait;
+    use InitializerTrait {
+        init as _init;
+    }
 
     // {{{ Properties
 
@@ -244,6 +248,14 @@ public function __construct($defaults = [])
             }
         }
     }
+
+    /**
+     * Initialization.
+     */
+    public function init()
+    {
+        $this->_init();
+    }
 
     /**
      * Validate and normalize value.
@@ -261,73 +273,20 @@ public function __construct($defaults = [])
      */
     public function normalize($value)
     {
-        // SQL fields are allowed to have expressions inside of them.
-        if ($value instanceof Expression ||
-            $value instanceof Expressionable) {
-            return $value;
-        }
-
         // NULL value is always fine if it is allowed
-        if ($value === null) {
+        if ($value === null || $value === '') {
             if ($this->required) {
-                throw new ValidationException([$this->name => 'Must not be null']);
+                throw new ValidationException([$this->name => 'Must not be null or empty']);
             }
-
-            return;
-        }
-
-        $f = $this;
-
-        // only string type fields can use empty string as legit value, for all
-        // other field types empty value is the same as no-value, nothing or null
-        if ($f->type && $f->type != 'string' && $value === '') {
-            if ($this->required) {
-                throw new ValidationException([$this->name => 'Must not be empty']);
-            }
-
-            return;
-        }
-
-        // validate scalar values
-        if (in_array($f->type, ['string', 'text', 'integer', 'money', 'float']) && !is_scalar($value)) {
-            throw new ValidationException([$this->name => 'Must use scalar value']);
-        }
-
-        // normalize
-        // @TODO remove this block in future - it's useless
-        switch ($f->type) {
-        case null: // loose comparison, but is OK here
-            // NOTE - this is not always the same as type=string. Need to review what else it can be and how type=null is used at all
-            if ($this->required && empty($value)) {
-                throw new ValidationException([$this->name => 'Must not be empty']);
-            }
-            break;
-        case 'string':
-            throw new Exception(['Use Field\Line for type=string', 'this'=>$this]);
-        case 'text':
-            throw new Exception(['Use Field\Text for type=text', 'this'=>$this]);
-        case 'integer':
-            throw new Exception(['Use Field\Integer for type=integer', 'this'=>$this]);
-        case 'float':
-            throw new Exception(['Use Field\Numeric for type=float', 'this'=>$this]);
-        case 'money':
-            throw new Exception(['Use Field\Money for type=money', 'this'=>$this]);
-        case 'boolean':
-            throw new Exception(['Use Field\Boolean for type=boolean', 'this'=>$this]);
-        case 'date':
-            throw new Exception(['Use Field\Date for type=date', 'this'=>$this]);
-        case 'datetime':
-            throw new Exception(['Use Field\DateTime for type=datetime', 'this'=>$this]);
-        case 'time':
-            throw new Exception(['Use Field\Time for type=time', 'this'=>$this]);
-        case 'array':
-            throw new Exception(['Use Field\Array_ for type=array', 'this'=>$this]);
-        case 'object':
-            throw new Exception(['Use Field\Object_ for type=object', 'this'=>$this]);
         }
 
         return $value;
     }
+
+    public static function isExpression($value)
+    {
+        return $value instanceof Expression || $value instanceof Expressionable;
+    }
 
     /**
      * Return array of seed properties of this Field object.
@@ -511,22 +470,48 @@ public function getCaption(): string
 
     /**
      * Returns typecasting callback if defined.
-     *
+     * 
+     * Typecasting can be defined as (in order of precedence)
+     * 
+     * * affects all typecasting for the field
+     * $user->addField('dob', ['Date', 'typecast'=>[$encode_fx, $decode_fx]]);
+     *  
+     * * affects typecasting for specific persistence class
+     * $user->addField('dob', ['Date', 'persistence'=>['atk4\data\Persistence\SQL'=>['typecast'=>[$encode_fx, $decode_fx]]]]);
+     * 
+     * * affects typecasting for all persistences
+     * $user->addField('dob', ['Date', 'persistence'=>['typecast'=>[$encode_fx, $decode_fx]]]);
+     * 
+     * * default typecasting (if none of above set) will be used for all fields of the class defined in field methods
+     * typecastSave / typecastLoad based on the $mode
+     * 
      * @param string $mode - load|save
-     *
+     * 
      * @return callable|false
      */
     public function getTypecaster($mode)
     {
         // map for backward compatibility with definition
         // [typecast_save_callback, typecast_load_callback]
         $map = [
-            'save' => 0,
-            'load' => 1,
+                'save' => 0,
+                'load' => 1
         ];
-
-        $fx = $this->typecast[$mode] ?? $this->typecast[$map[$mode]] ?? false;
-
+
+        $persistence = $this->getPersistence();
+
+        // persistence specific typecast
+        $specific = $persistence ? ($this->persistence[get_class($persistence)]['typecast'] ?? null) : null;
+
+        // get the typecast definition to be applied
+        // field specific or persistence specific or persistence general
+        $typecast = $this->typecast ?? $specific ?? $this->persistence['typecast'] ?? [];
+
+        // default typecaster is method in the field named typecastSave or typecastLoad if such method exists
+        $default = method_exists($this, 'typecast' . ucfirst($mode)) ? [$this, 'typecast' . ucfirst($mode)] : false;
+
+        $fx = $typecast[$mode] ?? $typecast[$map[$mode]] ?? $default;
+
         return is_callable($fx) ? $fx : false;
     }
 
@@ -550,6 +535,11 @@ public function getSerializer($mode)
 
         return is_callable($fx) ? $fx : false;
     }
+
+    public function getPersistence()
+    {
+        return $this->owner ? $this->owner->persistence : null;
+    }
 
     // }}}
 

src/Field/Boolean.php

@@ -4,18 +4,13 @@
 
 namespace atk4\data\Field;
 
-use atk4\core\InitializerTrait;
 use atk4\data\ValidationException;
 
 /**
  * Your favorite nullable binary type.
  */
 class Boolean extends \atk4\data\Field
 {
-    use InitializerTrait {
-        init as _init;
-    }
-
     /** @var string Field type for backward compatibility. */
     public $type = 'boolean';
 
@@ -52,7 +47,7 @@ class Boolean extends \atk4\data\Field
      */
     public function init()
     {
-        $this->_init();
+        parent::init();
 
         // Backwards compatibility
         if ($this->enum) {

src/Field/Callback.php

@@ -4,17 +4,11 @@
 
 namespace atk4\data\Field;
 
-use atk4\core\InitializerTrait;
-
 /**
  * Evaluate php expression after load.
  */
 class Callback extends \atk4\data\Field
 {
-    use InitializerTrait {
-        init as _init;
-    }
-
     /**
      * Method to execute for evaluation.
      *
@@ -55,12 +49,12 @@ class Callback extends \atk4\data\Field
      */
     public function init()
     {
-        $this->_init();
+        parent::init();
 
         $this->ui['table']['sortable'] = false;
 
-        $this->owner->onHook('afterLoad', function ($m) {
-            $m->data[$this->short_name] = call_user_func($this->fx ?: $this->expr, $m);
+        $this->owner->onHook('afterLoad', function ($model) {
+            $model->data[$this->short_name] = call_user_func($this->fx ?: $this->expr, $model);
         });
     }
 }

src/Field/Line.php

@@ -37,11 +37,7 @@ class Line extends Text
      */
     public function normalize($value)
     {
-        $value = parent::normalize($value);
-
         // remove all line-ends
-        $value = trim(str_replace(["\r", "\n"], '', $value));
-
-        return $value;
+        return trim(str_replace(["\r", "\n"], '', parent::normalize($value)));
     }
 }

src/Field/Numeric.php

@@ -102,26 +102,26 @@ public function normalize($value)
     /**
      * Round up to the nearest number.
      *
-     * @param float $n Number
-     * @param int   $p Precision
+     * @param float $nunber Number
+     * @param int   $precision Precision
      *
      * @return float
      */
-    protected function roundUp(float $n, int $p): float
+    protected function roundUp(float $nunber, int $precision): float
     {
-        return $p ? ceil($n / $p) * $p : ceil($n);
+        return $precision ? ceil($nunber / $precision) * $precision : ceil($nunber);
     }
 
     /**
      * Round down to the nearest number.
      *
-     * @param float $n Number
-     * @param int   $p Precision
+     * @param float $number Number
+     * @param int   $precision Precision
      *
      * @return float
      */
-    protected function roundDown(float $n, int $p): float
+    protected function roundDown(float $number, int $precision): float
     {
-        return $p ? floor($n / $p) * $p : floor($n);
+        return $precision ? floor($number / $precision) * $precision : floor($number);
     }
 }

src/Field/Object_.php

@@ -28,7 +28,7 @@ public function normalize($value)
     {
         if ($value === null || $value === '') {
             if ($this->required) {
-                throw new ValidationException([$this->name => 'Must not be null']);
+                throw new ValidationException([$this->name => 'Must not be null or empty']);
             }
 
             return;

src/Model.php

@@ -795,7 +795,7 @@ public function set($field, $value = null)
                 && $this->hook('normalize', [$f, $value]) !== false
                 && $this->strict_types
             ) {
-                $value = $f->normalize($value);
+                $value = $f->isExpression($value) ? $value : $f->normalize($value);
             }
         } catch (Exception $e) {
             $e->addMoreInfo('field', $field);