From 5ba44a03ea93b0e00bcf6632da1645dcf067f355 Mon Sep 17 00:00:00 2001
From: XavierGR <xavier.guiboud-ribaud@combodo.com>
Date: Fri, 18 Apr 2025 08:04:38 +0200
Subject: [PATCH] Add computed tag for attribute computation from OQL
 Expression

---
 core/attributedef.class.inc.php | 25 +++++++++++++++++++++++--
 core/dbobject.class.php         | 20 ++++++++++++++++++++
 core/metamodel.class.php        |  1 -
 setup/compiler.class.inc.php    | 15 +++++++++++++++
 4 files changed, 58 insertions(+), 3 deletions(-)

diff --git a/core/attributedef.class.inc.php b/core/attributedef.class.inc.php
index 9fc7b0105..43bd99394 100644
--- a/core/attributedef.class.inc.php
+++ b/core/attributedef.class.inc.php
@@ -181,6 +181,23 @@ abstract class AttributeDefinition
 		return $this->GetSearchType() != static::SEARCH_WIDGET_TYPE_RAW;
 	}
 
+	/**
+	 * @return bool
+	 */
+	public function IsComputed()
+	{
+		return $this->IsParam('expression');
+	}
+
+	/**
+	 * @return array
+	 * @throws \OQLException
+	 */
+	protected function GetComputedPrerequisiteAttributes(): array {
+		$oExpression = Expression::FromOQL($this->m_aParams['expression']);
+		return $oExpression->ListRequiredFields();
+	}
+
 	/** @var string */
 	protected $m_sCode;
 	/** @var array */
@@ -2717,7 +2734,11 @@ class AttributeDBFieldVoid extends AttributeDefinition
 
 	public function GetPrerequisiteAttributes($sClass = null)
 	{
-		return $this->Get("depends_on");
+		$aPrerequisiteAttributes = $this->Get("depends_on");
+		if($this->HasParam('expression')) {
+			$aPrerequisiteAttributes = array_merge($aPrerequisiteAttributes, $this->GetComputedPrerequisiteAttributes());
+		}
+		return $aPrerequisiteAttributes;
 	}
 
 	public static function IsBasedOnDBColumns()
@@ -2732,7 +2753,7 @@ class AttributeDBFieldVoid extends AttributeDefinition
 
 	public function IsWritable()
 	{
-		return !$this->IsMagic();
+		return !$this->IsMagic() && !$this->IsComputed();
 	}
 
 	public function GetSQLExpr()
diff --git a/core/dbobject.class.php b/core/dbobject.class.php
index 4068819e8..0c7cd86e9 100644
--- a/core/dbobject.class.php
+++ b/core/dbobject.class.php
@@ -708,6 +708,8 @@ abstract class DBObject implements iDisplay
 
 		$this->UpdateMetaAttributes(array($sAttCode));
 
+		$this->UpdateDependentComputedAttributes($sAttCode);
+
 		// The object has changed, reset caches
 		$this->m_bCheckStatus = null;
 
@@ -6992,5 +6994,23 @@ abstract class DBObject implements iDisplay
 	{
 		return array_key_exists($sSection, $this->aContext);
 	}
+
+	/**
+	 * @param string $sAttCode
+	 *
+	 * @return void
+	 * @throws CoreException
+	 * @throws OQLException
+	 */
+	private function UpdateDependentComputedAttributes(string $sAttCode): void
+	{
+		foreach (MetaModel::GetDependentAttributes(get_class($this), $sAttCode) as $sCode) {
+			$oAttDef = MetaModel::GetAttributeDef(get_class($this), $sCode);
+			if ($oAttDef->IsComputed()) {
+				$oExpression = Expression::FromOQL($oAttDef->GetParams()['expression']);
+				$this->_Set($sCode, $this->EvaluateExpression($oExpression));
+			}
+		}
+	}
 }
 
diff --git a/core/metamodel.class.php b/core/metamodel.class.php
index af9301bdf..41aecd2cd 100644
--- a/core/metamodel.class.php
+++ b/core/metamodel.class.php
@@ -2661,7 +2661,6 @@ abstract class MetaModel
 	 */
 	public static function GetAttributeFlags($sClass, $sState, $sAttCode)
 	{
-		$iFlags = 0; // By default (if no life cycle) no flag at all
 		if (self::HasLifecycle($sClass)) {
 			$aStates = MetaModel::EnumStates($sClass);
 			if (!array_key_exists($sState, $aStates)) {
diff --git a/setup/compiler.class.inc.php b/setup/compiler.class.inc.php
index a9394931a..915d30ea5 100644
--- a/setup/compiler.class.inc.php
+++ b/setup/compiler.class.inc.php
@@ -2134,6 +2134,7 @@ EOF
 			$this->CompileCommonProperty('default_value', $oField, $aParameters, $sModuleRelativeDir, '');
 			$this->CompileCommonProperty('is_null_allowed', $oField, $aParameters, $sModuleRelativeDir, false);
 			$this->CompileCommonProperty('allowed_values', $oField, $aParameters, $sModuleRelativeDir);
+			$this->CompileCommonProperty('computed', $oField, $aParameters, $sModuleRelativeDir, false);
 			$aParameters['depends_on'] = $sDependencies;
 		} elseif ($sAttType == 'AttributeEnum') {
 			$this->CompileAttributeEnumValues($sModuleRelativeDir, $sClass, $sAttCode, $oField, $aParameters, $sCss);
@@ -2141,6 +2142,7 @@ EOF
 			$this->CompileCommonProperty('sql', $oField, $aParameters, $sModuleRelativeDir);
 			$this->CompileCommonProperty('default_value', $oField, $aParameters, $sModuleRelativeDir, '');
 			$this->CompileCommonProperty('is_null_allowed', $oField, $aParameters, $sModuleRelativeDir, false);
+			$this->CompileCommonProperty('computed', $oField, $aParameters, $sModuleRelativeDir, false);
 			$aParameters['depends_on'] = $sDependencies;
 		} elseif ($sAttType == 'AttributeMetaEnum') {
 			$this->CompileAttributeEnumValues($sModuleRelativeDir, $sClass, $sAttCode, $oField, $aParameters, $sCss);
@@ -2269,6 +2271,7 @@ EOF
 			$this->CompileCommonProperty('is_null_allowed', $oField, $aParameters, $sModuleRelativeDir, false);
 			$this->CompileCommonProperty('default_value', $oField, $aParameters, $sModuleRelativeDir, '');
 			$this->CompileCommonProperty('allowed_values', $oField, $aParameters, $sModuleRelativeDir);
+			$this->CompileCommonProperty('computed', $oField, $aParameters, $sModuleRelativeDir, false);
 			$aParameters['depends_on'] = $sDependencies;
 		}
 
@@ -2413,7 +2416,19 @@ EOF
 					}
 					$aParameters['thresholds'] = 'array('.implode(', ', $aThresholds).')';
 					break;
+				case 'computed':
+					$oComputed = $oField->GetOptionalElement('computed');
+					if(is_null($oComputed)) {
+						break;
+					}
 
+					$sExpression = self::QuoteForPHP($oComputed->GetChildText('expression'));
+					if(is_null($sExpression) || $sExpression === '') {
+						throw new DOMFormatException("missing (or empty) mandatory tag expression under the tag '".$oField->nodeName."'");
+					}
+
+					$aParameters['expression'] = $sExpression;
+					break;
 				default:
 					return false;
 			}