From 156f63bce38a6b95d0f117eedbeb8819eb51d1b7 Mon Sep 17 00:00:00 2001
From: Christopher Joe <flamer.ohr@gmail.com>
Date: Mon, 6 Nov 2017 14:04:06 +1300
Subject: [PATCH] ENH shorten auto-generated table names

Fix add check for legacy long table name and rename to short version
---
 src/ORM/DataObject.php       | 21 +++++++++++++++++++++
 src/ORM/DataObjectSchema.php | 30 +++++++++++++++++++++++++++---
 2 files changed, 48 insertions(+), 3 deletions(-)

diff --git a/src/ORM/DataObject.php b/src/ORM/DataObject.php
index b236b253c96..ee7dd65ed41 100644
--- a/src/ORM/DataObject.php
+++ b/src/ORM/DataObject.php
@@ -3623,6 +3623,7 @@ public function requireTable()
         $fields = $schema->databaseFields(static::class, false);
         $indexes = $schema->databaseIndexes(static::class, false);
         $extensions = self::database_extensions(static::class);
+        $legacyTables = $schema->getLegacyTableNames(static::class);
 
         if (empty($table)) {
             throw new LogicException(
@@ -3630,6 +3631,26 @@ public function requireTable()
             );
         }
 
+        if ($legacyTables) {
+            $ignore = Config::inst()->get(static::class, 'ignored_legacy_tables') ?: [];
+            $renameTables = array_diff(
+                array_intersect($legacyTables, DB::table_list()),
+                $ignore
+            );
+            if (count($renameTables) > 1) {
+                $class = static::class;
+                $legacyList = implode(', ', $renameTables);
+                trigger_error(
+                    "Class $class has multiple legacy tables: $legacyList",
+                    E_USER_NOTICE
+                );
+            }
+            if (count($renameTables) === 1) {
+                $dbSchema = DB::get_schema();
+                $dbSchema->renameTable($renameTables[0], $table);
+            }
+        }
+
         if ($fields) {
             $hasAutoIncPK = get_parent_class($this ?? '') === self::class;
             DB::require_table(
diff --git a/src/ORM/DataObjectSchema.php b/src/ORM/DataObjectSchema.php
index dcd7ca17d7a..71aaaa430d1 100644
--- a/src/ORM/DataObjectSchema.php
+++ b/src/ORM/DataObjectSchema.php
@@ -318,18 +318,30 @@ protected function buildTableName($class)
     {
         $table = Config::inst()->get($class, 'table_name', Config::UNINHERITED);
 
-        // Generate default table name
+        // Return table name if configured
         if ($table) {
             return $table;
         }
 
+        // Use classname directly if not namespaced
         if (strpos($class ?? '', '\\') === false) {
             return $class;
         }
 
-        $separator = DataObjectSchema::config()->uninherited('table_namespace_separator');
-        $table = str_replace('\\', $separator ?? '', trim($class ?? '', '\\'));
+        // Attempt to generate a nice table name
+        $separator = DataObjectSchema::config()->uninherited('table_namespace_separator') ?? '';
+        $parts = explode('\\', trim($class ?? '', '\\'));
+        $vendor = array_slice($parts, 0, 1)[0];
+        $base = array_slice($parts, -1, 1)[0];
+        if ($vendor && $base && $vendor !== $base) {
+            $table = "{$vendor}{$separator}{$base}";
+        } elseif ($base) {
+            $table = $base;
+        } else {
+            throw new InvalidArgumentException("Unable to build a table name for class '$class'. Define a table_name for this class.");
+        }
 
+        // Display a warning about namespaced classes producing long table names
         if (!ClassInfo::classImplements($class, TestOnly::class) && $this->classHasTable($class)) {
             DBSchemaManager::showTableNameWarning($table, $class);
         }
@@ -337,6 +349,18 @@ protected function buildTableName($class)
         return $table;
     }
 
+    /**
+     * @param $class
+     * @return array
+     */
+    public function getLegacyTableNames($class)
+    {
+        $separator = DataObjectSchema::config()->uninherited('table_namespace_separator');
+        $names[] = str_replace('\\', $separator, trim($class, '\\'));
+
+        return $names;
+    }
+
     /**
      * Return the complete map of fields to specification on this object, including fixed_fields.
      * "ID" will be included on every table.