PeerConnectiveChat/PCC2.Gui/Data/Pcc2DbContext.cs

using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
using PCC2.Data.Entity;

namespace PCC2.Data
{
    public class Pcc2DbContext : DbContext
    {
        private const string DbFileName = "PCC2.DB3";

        public DbSet<Setting> Settings { get; set; } = null!;
        public DbSet<LocalPeer> LocalPeers { get; set; } = null!;
        public DbSet<RemotePeer> RemotePeers { get; set; } = null!;
        public DbSet<ChatRecord> ChatRecords { get; set; } = null!;

        protected override void OnConfiguring(DbContextOptionsBuilder optionsBuilder)
        {
            optionsBuilder.UseSqlite($"Data Source={DbFileName}");
        }

        protected override void OnModelCreating(ModelBuilder modelBuilder)
        {
            base.OnModelCreating(modelBuilder);

            // 创建 ValueConverter：将 DateTimeOffset 转换为 UTC 的 yyyyMMddHHmmssfff 格式
            var dateTimeOffsetToBigIntConverter = new ValueConverter<DateTimeOffset, long>(
                v => long.Parse(v.UtcDateTime.ToString("yyyyMMddHHmmssfff")),
                v => DateTimeOffset.ParseExact(v.ToString(), "yyyyMMddHHmmssfff", null, System.Globalization.DateTimeStyles.AssumeUniversal)
            );

            var nullableDateTimeOffsetToBigIntConverter = new ValueConverter<DateTimeOffset?, long?>(
                v => v.HasValue ? long.Parse(v.Value.UtcDateTime.ToString("yyyyMMddHHmmssfff")) : (long?)null,
                v => v.HasValue ? DateTimeOffset.ParseExact(v.Value.ToString(), "yyyyMMddHHmmssfff", null, System.Globalization.DateTimeStyles.AssumeUniversal) : (DateTimeOffset?)null
            );

            // 应用于所有 DateTimeOffset 字段
            foreach (var entityType in modelBuilder.Model.GetEntityTypes())
            {
                foreach (var property in entityType.GetProperties())
                {
                    if (property.ClrType == typeof(DateTimeOffset))
                    {
                        property.SetValueConverter(dateTimeOffsetToBigIntConverter);
                    }
                    else if (Nullable.GetUnderlyingType(property.ClrType) == typeof(DateTimeOffset))
                    {
                        property.SetValueConverter(nullableDateTimeOffsetToBigIntConverter);
                    }
                }
            }
        }
    }
}