PeerConnectiveChat/PCC.Gui/IO/PccDbContext.cs

using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
using PCC.DbEntity;

namespace PCC.IO;

internal class PccDbContext : DbContext
{
    private const string DbFileName = "PCC.DB3";


    public DbSet<ChatRecord> ChatRecords { get; set; } = null!;

    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);
                }
            }
        }
    }

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