using System;
using System.Linq;
using System.Threading;
using System.Threading.Tasks;
using Microsoft.EntityFrameworkCore;
using Models.Entities;
using Configurations;

public class ApplicationDbContext : DbContext
{
    public ApplicationDbContext(DbContextOptions<ApplicationDbContext> options)
        : base(options)
    {
    }

    public DbSet<Department> Departments => Set<Department>();
    public DbSet<Role> Roles => Set<Role>();
    public DbSet<Account> Accounts => Set<Account>();

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

        // ®M¥Î©Ò¦³ EntityTypeConfiguration
        modelBuilder.ApplyConfiguration(new DepartmentConfiguration());
        modelBuilder.ApplyConfiguration(new RoleConfiguration());
        modelBuilder.ApplyConfiguration(new AccountConfiguration());
    }

    public override int SaveChanges()
    {
        ApplyTimestamps();
        return base.SaveChanges();
    }

    public override Task<int> SaveChangesAsync(CancellationToken cancellationToken = default)
    {
        ApplyTimestamps();
        return base.SaveChangesAsync(cancellationToken);
    }

    private void ApplyTimestamps()
    {
        var utcNow = DateTime.UtcNow;

        foreach (var entry in ChangeTracker.Entries<BaseEntity>())
        {
            switch (entry.State)
            {
                case EntityState.Added:
                    entry.Entity.CreatedAt = utcNow;
                    entry.Entity.UpdatedAt = null;
                    break;

                case EntityState.Modified:
                    // ÁקK­×§ï CreatedAt
                    entry.Property(e => e.CreatedAt).IsModified = false;
                    entry.Entity.UpdatedAt = utcNow;
                    break;
            }
        }
    }
}