Add new Fieldtype::saveFieldReady(Field $field) hook that is called right before a Field object is about to be saved. For newly created fields, the given $field will have $field->id==0

wire/core/Fields.php

@@ -5,7 +5,7 @@
  *
  * Manages collection of ALL Field instances, not specific to any particular Fieldgroup
  * 
- * ProcessWire 3.x, Copyright 2022 by Ryan Cramer
+ * ProcessWire 3.x, Copyright 2023 by Ryan Cramer
  * https://processwire.com
  * 
  * #pw-summary Manages all custom fields in ProcessWire, independently of any Fieldgroup. 
@@ -357,6 +357,7 @@ class Fields extends WireSaveableItems {
 		}
 
 		if(!$item->type) throw new WireException("Can't save a Field that doesn't have it's 'type' property set to a Fieldtype"); 
+		$item->type->saveFieldReady($item);
 		if(!parent::___save($item)) return false;
 		if($isNew) $item->type->createField($item); 
 
@@ -773,7 +774,7 @@ class Fields extends WireSaveableItems {
 			// so use verbose/slow method to delete the field from pages
 			
 			$ids = $this->getNumPages($field, array('template' => $template, 'getPageIDs' => true)); 
-			$items = $this->wire('pages')->getById($ids, $template); 
+			$items = $this->wire()->pages->getById($ids, $template); 
 			
 			foreach($items as $page) {
 				try {
@@ -791,7 +792,7 @@ class Fields extends WireSaveableItems {
 			
 			// large number of pages to operate on: use fast method
 			
-			$database = $this->wire('database');
+			$database = $this->wire()->database;
 			$table = $database->escapeTable($field->getTable());
 			$sql = 	"DELETE $table FROM $table " .
 					"INNER JOIN pages ON pages.id=$table.pages_id " .

wire/core/Fieldtype.php

@@ -47,6 +47,7 @@
  * @method Field cloneField(Field $field)
  * @method void renamedField(Field $field, $prevName) 
  * @method void savedField(Field $field)
+ * @method void saveFieldReady(Field $field)
  * @method void install()
  * @method void uninstall()
  * 
@@ -992,8 +993,9 @@ abstract class Fieldtype extends WireData implements Module {
 					if($a == 'CHARSET') $info['charset'] = $b;
 				}
 			}
-			if(!$info['engine']) $info['engine'] = $this->wire('config')->dbEngine;
+			$config = $this->wire()->config;
-			if(!$info['charset']) $info['charset'] = $this->wire('config')->dbCharset;
+			if(!$info['engine']) $info['engine'] = $config->dbEngine;
+			if(!$info['charset']) $info['charset'] = $config->dbCharset;
 			if($info['engine']) $info['engine'] = str_replace(array('MYISAM', 'INNODB'), array('MyISAM', 'InnoDB'), $info['engine']);
 			$info['transactions'] = $info['engine'] == 'InnoDB';
 		}
@@ -1505,6 +1507,7 @@ abstract class Fieldtype extends WireData implements Module {
 	 * Most Fieldtypes don't need to do anything here, but this exists just in case.
 	 * 
 	 * #pw-internal
+	 * #pw-hooker
 	 * 
 	 * @param Field $field
 	 * @param string $prevName Previous name (current name can be found in $field->name)
@@ -1513,12 +1516,30 @@ abstract class Fieldtype extends WireData implements Module {
 	public function ___renamedField(Field $field, $prevName) {
 	}
 
+	/**
+	 * Hook called by Fields::save() when a field is about to be saved
+	 * 
+	 * If field is a new field it will not yet have an id. 
+	 *
+	 * #pw-internal
+	 * #pw-hooker
+	 *
+	 * @param Field $field
+	 * @since 3.0.212
+	 *
+	 */
+	public function ___saveFieldReady(Field $field) {
+	}
+
 	/**
 	 * Called when Field using this Fieldtype has been saved 
 	 * 
 	 * This is primarily so that Fieldtype modules can identify when their fields are 
 	 * saved without having to add a hook to the $fields API var. 
 	 * 
+	 * #pw-internal
+	 * #pw-hooker
+	 * 
 	 * @param Field $field
 	 * @since 3.0.171
 	 *