From 2d3f41da6f08e001f70cfeb2c172693c1e51eedf Mon Sep 17 00:00:00 2001
From: Jonas Kvinge <jonas@jkvinge.net>
Date: Fri, 2 Aug 2019 22:58:30 +0200
Subject: [PATCH] Automatically remove devices with old schemas when upgrading

---
 data/schema/device-schema.sql        |  2 +-
 src/core/database.cpp                |  5 ++++-
 src/device/devicedatabasebackend.cpp | 21 ++++++++++++++++-----
 3 files changed, 21 insertions(+), 7 deletions(-)

diff --git a/data/schema/device-schema.sql b/data/schema/device-schema.sql
index 6d7740a8a..c4edc08ed 100644
--- a/data/schema/device-schema.sql
+++ b/data/schema/device-schema.sql
@@ -75,4 +75,4 @@ CREATE VIRTUAL TABLE device_%deviceid_fts USING fts5(
   tokenize = "unicode61 remove_diacritics 0"
 );
 
-UPDATE devices SET schema_version=0 WHERE ROWID=%deviceid;
+UPDATE devices SET schema_version=1 WHERE ROWID=%deviceid;
diff --git a/src/core/database.cpp b/src/core/database.cpp
index cea845089..87febd775 100644
--- a/src/core/database.cpp
+++ b/src/core/database.cpp
@@ -147,7 +147,10 @@ QSqlDatabase Database::Connect() {
     UpdateDatabaseSchema(0, db);
   }
 
-  else if (SchemaVersion(&db) <= 8) { //  Register unicode from unicode61 tokenizer to drop old FTS3 tables.
+  {
+    //  Register unicode from unicode61 tokenizer to drop old FTS3 tables.
+    //  We need it also to drop old devices later when loading devices.
+    //  And that's done in a different thread after schemas are upgraded, so register it anyway.
 #ifdef SQLITE_DBCONFIG_ENABLE_FTS3_TOKENIZER
     QVariant v = db.driver()->handle();
     if (v.isValid() && qstrcmp(v.typeName(), "sqlite3*") == 0) {
diff --git a/src/device/devicedatabasebackend.cpp b/src/device/devicedatabasebackend.cpp
index 31c1cb242..5c52914ed 100644
--- a/src/device/devicedatabasebackend.cpp
+++ b/src/device/devicedatabasebackend.cpp
@@ -40,7 +40,7 @@
 #include "core/logging.h"
 #include "devicedatabasebackend.h"
 
-const int DeviceDatabaseBackend::kDeviceSchemaVersion = 0;
+const int DeviceDatabaseBackend::kDeviceSchemaVersion = 1;
 
 DeviceDatabaseBackend::DeviceDatabaseBackend(QObject *parent) :
     QObject(parent),
@@ -81,12 +81,13 @@ void DeviceDatabaseBackend::Exit() {
 DeviceDatabaseBackend::DeviceList DeviceDatabaseBackend::GetAllDevices() {
 
   DeviceList ret;
+  DeviceList old_devices;
 
   {
     QMutexLocker l(db_->Mutex());
     QSqlDatabase db(db_->Connect());
     QSqlQuery q(db);
-    q.prepare("SELECT ROWID, unique_id, friendly_name, size, icon, transcode_mode, transcode_format FROM devices");
+    q.prepare("SELECT ROWID, unique_id, friendly_name, size, icon, schema_version, transcode_mode, transcode_format FROM devices");
     q.exec();
     if (db_->CheckErrors(q)) return ret;
 
@@ -97,12 +98,22 @@ DeviceDatabaseBackend::DeviceList DeviceDatabaseBackend::GetAllDevices() {
       dev.friendly_name_ = q.value(2).toString();
       dev.size_ = q.value(3).toLongLong();
       dev.icon_name_ = q.value(4).toString();
-      dev.transcode_mode_ = MusicStorage::TranscodeMode(q.value(5).toInt());
-      dev.transcode_format_ = Song::FileType(q.value(6).toInt());
-      ret << dev;
+      int schema_version = q.value(5).toInt();
+      dev.transcode_mode_ = MusicStorage::TranscodeMode(q.value(6).toInt());
+      dev.transcode_format_ = Song::FileType(q.value(7).toInt());
+      if (schema_version < kDeviceSchemaVersion) { // Device is using old schema, drop it.
+        old_devices << dev;
+      }
+      else {
+        ret << dev;
+      }
     }
   }
 
+  for (Device dev : old_devices) {
+    RemoveDevice(dev.id_);
+  }
+
   Close();
 
   return ret;