Adds initial progress

source/Database/DatabaseConnection.ts

@@ -0,0 +1,44 @@
+import {DatabaseEnvironment, Environment} from "../Environment";
+import Sqlite3 from "better-sqlite3";
+import Database from "better-sqlite3";
+import {Container} from "../Container/Container";
+import {Logger} from "log4js";
+
+export class DatabaseConnection {
+    private static connection: DatabaseConnection;
+    
+    private database: Sqlite3.Database;
+    
+    constructor(private readonly env: DatabaseEnvironment) {
+        this.database = new Database(env.path, {
+            nativeBinding: "node_modules/better-sqlite3/build/Release/better_sqlite3.node",
+        })
+        this.database.pragma('journal_mode = WAL');
+    }
+    
+    public execute(query: string, ...args: any[]): Sqlite3.RunResult {
+        try {
+            const preparedQuery = this.database.prepare(query);
+            return preparedQuery.run(args);
+        } catch (error) {
+            Container.get<Logger>("logger").error("Failed to execute database connection", error, query, args);
+            throw error;
+        }
+    }
+
+    public fetch<BindParameters extends unknown[] | {} = unknown[], Result = unknown>(query: string, ...args: any[]): Result|undefined {
+        const preparedQuery = this.database.prepare<BindParameters, Result>(query);
+        return preparedQuery.get(args);
+    }
+    public fetchAll<BindParameters extends unknown[] | {} = unknown[], Result = unknown>(query: string, ...args: any[]): Result[] {
+        const preparedQuery = this.database.prepare<BindParameters, Result>(query);
+        return preparedQuery.all(args);
+    }
+    
+    public hasTable(tableName: string): boolean {
+        const sql = "SELECT COUNT(*) as tableCount FROM sqlite_master WHERE type='table' AND name=? LIMIT 1;";
+        
+        const result = this.fetch<string[], {tableCount: number}>(sql,  tableName);
+        return result != undefined && result.tableCount > 0;
+    }
+}