Large refactor and project restructuring

PluralKit.Core/Utils/InitUtils.cs

@@ -0,0 +1,57 @@
+using System.IO;
+
+using Dapper;
+
+using Microsoft.Extensions.Configuration;
+
+using Newtonsoft.Json;
+
+using NodaTime;
+using NodaTime.Serialization.JsonNet;
+
+using Npgsql;
+
+namespace PluralKit.Core {
+    public static class InitUtils
+    {
+        public static IConfigurationBuilder BuildConfiguration(string[] args) => new ConfigurationBuilder()
+            .SetBasePath(Directory.GetCurrentDirectory())
+            .AddJsonFile("pluralkit.conf", true)
+            .AddEnvironmentVariables()
+            .AddCommandLine(args);
+
+        public static void Init()
+        {
+            InitDatabase();
+        }
+        
+        private static void InitDatabase()
+        {
+            // Dapper by default tries to pass ulongs to Npgsql, which rejects them since PostgreSQL technically
+            // doesn't support unsigned types on its own.
+            // Instead we add a custom mapper to encode them as signed integers instead, converting them back and forth.
+            SqlMapper.RemoveTypeMap(typeof(ulong));
+            SqlMapper.AddTypeHandler<ulong>(new UlongEncodeAsLongHandler());
+            Dapper.DefaultTypeMap.MatchNamesWithUnderscores = true;
+
+            // Also, use NodaTime. it's good.
+            NpgsqlConnection.GlobalTypeMapper.UseNodaTime();
+            // With the thing we add above, Npgsql already handles NodaTime integration
+            // This makes Dapper confused since it thinks it has to convert it anyway and doesn't understand the types
+            // So we add a custom type handler that literally just passes the type through to Npgsql
+            SqlMapper.AddTypeHandler(new PassthroughTypeHandler<Instant>());
+            SqlMapper.AddTypeHandler(new PassthroughTypeHandler<LocalDate>());
+
+            // Add global type mapper for ProxyTag compound type in Postgres
+            NpgsqlConnection.GlobalTypeMapper.MapComposite<ProxyTag>("proxy_tag");
+        }
+        
+        public static JsonSerializerSettings BuildSerializerSettings() => new JsonSerializerSettings().BuildSerializerSettings();
+
+        public static JsonSerializerSettings BuildSerializerSettings(this JsonSerializerSettings settings)
+        {
+            settings.ConfigureForNodaTime(DateTimeZoneProviders.Tzdb);
+            return settings;
+        }
+    }
+}