fix CategoryMetaTable reference to CategoryTable (#473)

server/src/main/kotlin/suwayomi/tachidesk/server/database/migration/M0023_CategoryMetaRefFix.kt

@@ -0,0 +1,35 @@
+package suwayomi.tachidesk.server.database.migration
+
+/*
+ * Copyright (C) Contributors to the Suwayomi project
+ *
+ * This Source Code Form is subject to the terms of the Mozilla Public
+ * License, v. 2.0. If a copy of the MPL was not distributed with this
+ * file, You can obtain one at https://mozilla.org/MPL/2.0/. */
+
+import de.neonew.exposed.migrations.helpers.SQLMigration
+import org.jetbrains.exposed.sql.transactions.TransactionManager
+
+@Suppress("ClassName", "unused")
+class M0023_CategoryMetaRefFix : SQLMigration() {
+    fun String.toSqlName(): String =
+        TransactionManager.defaultDatabase!!.identifierManager.let {
+            it.quoteIfNecessary(
+                it.inProperCase(this)
+            )
+        }
+
+    private val CategoryMetaTable by lazy { "CategoryMeta".toSqlName() }
+    private val CategoryRefColumn by lazy { "category_ref".toSqlName() }
+    private val CategoryTable by lazy { "Category".toSqlName() }
+
+    override val sql by lazy {
+        // Incorrectly referenced in M0021
+        """
+        ALTER TABLE $CategoryMetaTable DROP COLUMN $CategoryRefColumn;
+        ALTER TABLE $CategoryMetaTable ADD COLUMN $CategoryRefColumn INT DEFAULT 0;   
+        ALTER TABLE $CategoryMetaTable ADD FOREIGN KEY ($CategoryRefColumn) 
+                                    REFERENCES $CategoryTable(ID) ON DELETE CASCADE;
+        """
+    }
+}