From 5c01063bbfbe0f22d6942a36568aee3d2279819f Mon Sep 17 00:00:00 2001
From: Florindo <florindo@toomba.nl>
Date: Tue, 28 Mar 2017 16:01:14 +0200
Subject: [PATCH] new function ChangeField into the manager to change a column
 without drop the existing content, you must update the schema xml changing
 the field befor call this function

---
 core/xpdo/om/mysql/xpdomanager.class.php  | 33 +++++++++++++++++++++++
 core/xpdo/om/sqlite/xpdomanager.class.php |  8 ++++++
 core/xpdo/om/sqlsrv/xpdomanager.class.php | 33 +++++++++++++++++++++++
 core/xpdo/om/xpdomanager.class.php        | 11 ++++++++
 4 files changed, 85 insertions(+)

diff --git a/core/xpdo/om/mysql/xpdomanager.class.php b/core/xpdo/om/mysql/xpdomanager.class.php
index fb2ba886ad0..266b541dcc4 100644
--- a/core/xpdo/om/mysql/xpdomanager.class.php
+++ b/core/xpdo/om/mysql/xpdomanager.class.php
@@ -375,6 +375,39 @@ public function alterField($class, $name, array $options = array()) {
         return $result;
     }
 
+    public function changeField($class, $oldName, $newName, array $options = array()) {
+        $result = false;
+        if ($this->xpdo->getConnection(array(xPDO::OPT_CONN_MUTABLE => true))) {
+            $className = $this->xpdo->loadClass($class);
+            if ($className) {
+                $meta = $this->xpdo->getFieldMeta($className, true);
+                if (is_array($meta) && array_key_exists($newName, $meta)) {
+                    $colDef = $this->getColumnDef($className, $newName, $meta[$newName]);
+                    if (!empty($colDef)) {
+                        $sql = "ALTER TABLE {$this->xpdo->getTableName($className)} CHANGE COLUMN {$oldName} {$colDef}";
+                        if (isset($options['first']) && !empty($options['first'])) {
+                            $sql .= " FIRST";
+                        } elseif (isset($options['after']) && array_key_exists($options['after'], $meta)) {
+                            $sql .= " AFTER {$this->xpdo->escape($options['after'])}";
+                        }
+                        if ($this->xpdo->exec($sql) !== false) {
+                            $result = true;
+                        } else {
+                            $this->xpdo->log(xPDO::LOG_LEVEL_ERROR, "Error altering field {$class}->{$newName}: " . print_r($this->xpdo->errorInfo(), true), '', __METHOD__, __FILE__, __LINE__);
+                        }
+                    } else {
+                        $this->xpdo->log(xPDO::LOG_LEVEL_ERROR, "Error altering field {$class}->{$newName}: Could not get column definition");
+                    }
+                } else {
+                    $this->xpdo->log(xPDO::LOG_LEVEL_ERROR, "Error altering field {$class}->{$newName}: No metadata defined");
+                }
+            }
+        } else {
+            $this->xpdo->log(xPDO::LOG_LEVEL_ERROR, "Could not get writable connection", '', __METHOD__, __FILE__, __LINE__);
+        }
+        return $result;
+    }
+
     public function removeConstraint($class, $name, array $options = array()) {
         if ($this->xpdo->getConnection(array(xPDO::OPT_CONN_MUTABLE => true))) {
             // TODO: Implement removeConstraint() method.
diff --git a/core/xpdo/om/sqlite/xpdomanager.class.php b/core/xpdo/om/sqlite/xpdomanager.class.php
index ecf013a416a..573fc5f3341 100644
--- a/core/xpdo/om/sqlite/xpdomanager.class.php
+++ b/core/xpdo/om/sqlite/xpdomanager.class.php
@@ -254,6 +254,14 @@ public function alterField($class, $name, array $options = array()) {
         return $result;
     }
 
+    public function changeField($class, $name, array $options = array()) {
+        $result = false;
+        if ($this->xpdo->getConnection(array(xPDO::OPT_CONN_MUTABLE => true))) {
+            // TODO: Implement changeField() method somehow, no support in sqlite for altering existing columns
+        }
+        return $result;
+    }
+
     public function removeConstraint($class, $name, array $options = array()) {
         $result = false;
         if ($this->xpdo->getConnection(array(xPDO::OPT_CONN_MUTABLE => true))) {
diff --git a/core/xpdo/om/sqlsrv/xpdomanager.class.php b/core/xpdo/om/sqlsrv/xpdomanager.class.php
index a7181a40e8e..0895084f388 100644
--- a/core/xpdo/om/sqlsrv/xpdomanager.class.php
+++ b/core/xpdo/om/sqlsrv/xpdomanager.class.php
@@ -301,6 +301,39 @@ public function alterField($class, $name, array $options = array()) {
         return $result;
     }
 
+    public function changeField($class, $oldName, $newName, array $options = array()) {
+        $result = false;
+        if ($this->xpdo->getConnection(array(xPDO::OPT_CONN_MUTABLE => true))) {
+            $className = $this->xpdo->loadClass($class);
+            if ($className) {
+                $meta = $this->xpdo->getFieldMeta($className, true);
+                if (is_array($meta) && array_key_exists($newName, $meta)) {
+                    $colDef = $this->getColumnDef($className, $newName, $meta[$newName]);
+                    if (!empty($colDef)) {
+                        $sql = "ALTER TABLE {$this->xpdo->getTableName($className)} CHANGE COLUMN {$oldName} {$colDef}";
+                        if (isset($options['first']) && !empty($options['first'])) {
+                            $sql .= " FIRST";
+                        } elseif (isset($options['after']) && array_key_exists($options['after'], $meta)) {
+                            $sql .= " AFTER {$this->xpdo->escape($options['after'])}";
+                        }
+                        if ($this->xpdo->exec($sql) !== false) {
+                            $result = true;
+                        } else {
+                            $this->xpdo->log(xPDO::LOG_LEVEL_ERROR, "Error altering field {$class}->{$newName}: " . print_r($this->xpdo->errorInfo(), true), '', __METHOD__, __FILE__, __LINE__);
+                        }
+                    } else {
+                        $this->xpdo->log(xPDO::LOG_LEVEL_ERROR, "Error altering field {$class}->{$newName}: Could not get column definition");
+                    }
+                } else {
+                    $this->xpdo->log(xPDO::LOG_LEVEL_ERROR, "Error altering field {$class}->{$newName}: No metadata defined");
+                }
+            }
+        } else {
+            $this->xpdo->log(xPDO::LOG_LEVEL_ERROR, "Could not get writable connection", '', __METHOD__, __FILE__, __LINE__);
+        }
+        return $result;
+    }
+
     public function removeConstraint($class, $name, array $options = array()) {
         $result = false;
         if ($this->xpdo->getConnection(array(xPDO::OPT_CONN_MUTABLE => true))) {
diff --git a/core/xpdo/om/xpdomanager.class.php b/core/xpdo/om/xpdomanager.class.php
index 82787a0f4d4..e78b7b81874 100644
--- a/core/xpdo/om/xpdomanager.class.php
+++ b/core/xpdo/om/xpdomanager.class.php
@@ -132,6 +132,17 @@ abstract public function addField($class, $name, array $options = array());
      */
     abstract public function alterField($class, $name, array $options = array());
 
+    /**
+     * Change an existing field of an object container, e.g. CHANGE COLUMN.
+     *
+     * @param string $class The object class to alter the field of.
+     * @param string $oldName The name of the old field you want change.
+     * @param string $newName The name of the new field you want set.
+     * @param array $options An array of options for the process for the new field.
+     * @return boolean True if the column is altered successfully, otherwise false.
+     */
+    abstract public function changeField($class, $oldName, $newName, array $options = array());
+
     /**
      * Remove a field from an object container, e.g. DROP COLUMN.
      *