Initial commit

core/db/database_manager.cpp

@@ -0,0 +1,111 @@
+#include "database_manager.h"
+
+#include "config.h"
+#include "execute_sql_file.h"
+#include <QFile>
+#include <QSqlError>
+#include <qsqldatabase.h>
+
+DatabaseManager::~DatabaseManager() {
+  disconnectDefaultDatabase();
+
+  QString defaultConnectionName = QSqlDatabase::database().connectionName();
+  QSqlDatabase::removeDatabase(QSqlDatabase::database().connectionName());
+
+  qInfo() << "Database with default connection name:" << defaultConnectionName
+          << "was removed";
+}
+
+DatabaseManager::CreateDatabaseResult
+DatabaseManager::createDefaultDatabaseIfMissing(
+    const QString &databaseFileName) {
+  if (QFile::exists(databaseFileName)) {
+    qInfo()
+        << "Database file name already exists and will not be created again:"
+        << databaseFileName;
+    return CreateDatabaseResult::AlreadyExists;
+  }
+
+  if (!connectToDefaultDatabase(databaseFileName)) {
+    qWarning() << "Failed to create and connect to the database";
+    return CreateDatabaseResult::Error;
+  }
+
+  // Execute SQL files to initialize the database
+  QStringList sqlFiles = {":/sql/create_tables.sql", ":/sql/create_indexes.sql",
+                          ":/sql/create_views.sql", ":/sql/create_triggers.sql",
+                          ":/sql/insert_role.sql"};
+
+#ifndef NDEBUG
+  QStringList additionalSqlFiles = {
+      ":/sql/insert_genre.sql", ":/sql/insert_hall.sql",
+      ":/sql/insert_movie.sql", ":/sql/insert_user.sql"};
+  sqlFiles.append(additionalSqlFiles);
+#endif
+
+  QSqlDatabase defaultDatabase = QSqlDatabase::database();
+  bool success = executeSqlFiles(sqlFiles, defaultDatabase);
+  disconnectDefaultDatabase();
+
+  if (success) {
+    qInfo() << "Database created and initialized successfully";
+    return CreateDatabaseResult::Success;
+  }
+
+  qWarning() << "Failed to execute initialization SQL files";
+
+  if (QFile::remove(databaseFileName)) {
+    qInfo() << "Database file deleted due to initialization failure:"
+            << databaseFileName;
+  } else {
+    qWarning() << "Failed to delete database file:" << databaseFileName;
+  }
+
+  return CreateDatabaseResult::Error;
+}
+
+bool DatabaseManager::connectToDefaultDatabase(
+    const QString &databaseFileName) {
+  QSqlDatabase defaultDatabase = QSqlDatabase::database();
+
+  defaultDatabase.setDatabaseName(databaseFileName);
+  if (defaultDatabase.isValid() && defaultDatabase.isOpen()) {
+    qInfo() << "Database is already connected";
+    return true;
+  }
+
+  // Constructor does not open/close the connection
+  defaultDatabase = QSqlDatabase::addDatabase(DATABASE_DRIVER);
+  defaultDatabase.setDatabaseName(databaseFileName);
+
+  if (!defaultDatabase.open()) {
+    qWarning() << "Failed to connect to the database:" << databaseFileName;
+    return false;
+  }
+
+  qDebug() << "Database was connected successfully: Connection name:"
+           << defaultDatabase.connectionName();
+
+  return true;
+}
+
+void DatabaseManager::disconnectDefaultDatabase() {
+  QSqlDatabase defaultDatabase = QSqlDatabase::database();
+  if (defaultDatabase.isOpen()) {
+    defaultDatabase.close();
+    qInfo() << "Database disconnected";
+  }
+}
+
+bool DatabaseManager::executeSqlFiles(const QStringList &filePaths,
+                                      QSqlDatabase &database) {
+  ExecuteSqlFile executor(database);
+  for (const QString &filePath : filePaths) {
+    qInfo() << "Executing SQL file:" << filePath;
+    if (!executor(filePath)) {
+      qWarning() << "Failed to execute SQL file:" << filePath;
+      return false;
+    }
+  }
+  return true;
+}