From 19c91f1f70c34e0ab366c90f80a2238eb2c0f837 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Jos=C3=A9=20Lorenzo=20Rodr=C3=ADguez?= <jose.zap@gmail.com>
Date: Tue, 10 Nov 2009 01:08:07 -0430
Subject: [PATCH] Initial implementation of model virtual fields

---
 cake/libs/model/datasources/dbo_source.php    | 43 ++++++++++++++++++-
 .../cases/libs/model/model_read.test.php      | 16 +++++++
 2 files changed, 58 insertions(+), 1 deletion(-)

diff --git a/cake/libs/model/datasources/dbo_source.php b/cake/libs/model/datasources/dbo_source.php
index dcaf899809b..1c49445b650 100644
--- a/cake/libs/model/datasources/dbo_source.php
+++ b/cake/libs/model/datasources/dbo_source.php
@@ -366,9 +366,11 @@ function fetchAll($sql, $cache = true, $modelName = null) {
 
 			$first = $this->fetchRow();
 			if ($first != null) {
+				$this->fetchVirtualField($first);
 				$out[] = $first;
 			}
 			while ($this->hasResult() && $item = $this->fetchResult()) {
+				$this->fetchVirtualField($item);
 				$out[] = $item;
 			}
 
@@ -386,6 +388,29 @@ function fetchAll($sql, $cache = true, $modelName = null) {
 		}
 	}
 
+	function fetchVirtualField(&$result) {
+		if (isset($result[0]) && is_array($result[0])) {
+			foreach ($result[0] as $field => $value) {
+				if (strpos($field,'__') === false) {
+					continue;
+				}
+				list($alias,$virtual) = explode('__',$field);
+
+				if (!ClassRegistry::isKeySet($alias)) {
+					retrun;
+				}
+				$model = ClassRegistry::getObject($alias);
+				if (isset($model->virtualFields[$virtual])) {
+					$result[$alias][$virtual] = $value;
+					unset($result[0][$field]);
+				}
+			}
+			if (empty($result[0])) {
+				unset($result[0]);
+			}
+		}
+	}
+
 /**
  * Returns a single field of the first of query results for a given SQL query, or false if empty.
  *
@@ -1733,6 +1758,14 @@ function __scrubQueryData($data) {
 		return $data;
 	}
 
+	function _constructVirtualFields(&$model,$fields) {
+		$virtual = array();
+		foreach ($fields as $name => $expression) {
+			$virtual[] = $expression . " {$this->alias} {$model->alias}__{$name}";
+		}
+		return $virtual;
+	}
+
 /**
  * Generates the fields list of an SQL query.
  *
@@ -1746,7 +1779,8 @@ function fields(&$model, $alias = null, $fields = array(), $quote = true) {
 		if (empty($alias)) {
 			$alias = $model->alias;
 		}
-		if (empty($fields)) {
+		$allFields = empty($fields);
+		if ($allFields) {
 			$fields = array_keys($model->schema());
 		} elseif (!is_array($fields)) {
 			$fields = String::tokenize($fields);
@@ -1813,6 +1847,13 @@ function fields(&$model, $alias = null, $fields = array(), $quote = true) {
 				}
 			}
 		}
+		
+		if (!empty($model->virtualFields)) {
+			if ($allFields) {
+				$fields = array_merge($fields,$this->_constructVirtualFields($model,$model->virtualFields));
+			} else {
+			}
+		}
 		return array_unique($fields);
 	}
 
diff --git a/cake/tests/cases/libs/model/model_read.test.php b/cake/tests/cases/libs/model/model_read.test.php
index 86b855900ac..2fd4978a716 100644
--- a/cake/tests/cases/libs/model/model_read.test.php
+++ b/cake/tests/cases/libs/model/model_read.test.php
@@ -26,6 +26,22 @@
  */
 class ModelReadTest extends BaseModelTest {
 
+	function testVirtualFields() {
+		$this->loadFixtures('Post');
+		$Post = ClassRegistry::init('Post');
+		$Post->virtualFields = array('two' => "1 + 1");
+		$expected = array(
+			'author_id' => 1,
+			'title' => 'First Post',
+			'body' => 'First Post Body',
+			'published' => 'Y',
+			'created' => '2007-03-18 10:39:23',
+			'updated' => '2007-03-18 10:41:31'
+		);
+		debug($Post->find('first'));
+		exit;
+	}
+
 /**
  * testFetchingNonUniqueFKJoinTableRecords()
  *