using Complex.Application;
using Complex.Domain.Commons;
using Complex.Domain.Entities;
using Complex.Infrastructure.Extensions;
using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.ChangeTracking;
using Microsoft.EntityFrameworkCore.Metadata;
using Microsoft.EntityFrameworkCore.Metadata.Internal;
using Microsoft.EntityFrameworkCore.Storage.ValueConversion;
using System;
using System.Collections.Generic;
using System.ComponentModel.DataAnnotations;
using System.Linq;
using System.Linq.Expressions;
using System.Reflection.Emit;
using System.Reflection.Metadata;
using System.Text;
using System.Threading.Tasks;

namespace Complex.Infrastructure
{
    public partial class ComplexDBContext : DbContext, IComplexDBContext
    {
        public ComplexDBContext()
        {

        }
        public object? Find(Type entityType, object keyId)
        {
            return base.Find(entityType, keyId);
        }
        public override EntityEntry Add(object entity)
        {
            return base.Add(entity);
        }
        public ComplexDBContext(DbContextOptions<ComplexDBContext> options)
            : base(options)
        {
        }
        protected override void OnModelCreating(ModelBuilder builder)
        {
            foreach (var entityType in builder.Model.GetEntityTypes())
            {
                if (entityType.ClrType.GetCustomAttributes(typeof(AuditableAttribute), true).Length > 0)
                {
                    builder.Entity(entityType.Name).Property<DateTime>("InsertTime").HasDefaultValue(DateTime.Now);
                    builder.Entity(entityType.Name).Property<DateTime?>("UpdateTime");
                    builder.Entity(entityType.Name).Property<DateTime?>("RemoveTime");
                    builder.Entity(entityType.Name).Property<bool>("IsRemoved").HasDefaultValue(false);
                }
            }
            builder.Entity<ComplexEntity>().HasQueryFilter(b => EF.Property<bool>(b, "IsRemoved") == false);
            builder.Entity<Unit>().HasQueryFilter(b => EF.Property<bool>(b, "IsRemoved") == false);
            builder.Entity<UnitCost>().HasQueryFilter(b => EF.Property<bool>(b, "IsRemoved") == false);
            builder.Entity<CostCycle>().HasQueryFilter(b => EF.Property<bool>(b, "IsRemoved") == false);

            // Configure many-to-many between CostCycle and Unit
            // SQL Server does not allow multiple cascade paths, so one side must use NoAction
            builder.Entity<CostCycle>()
                .HasMany(cc => cc.Units)
                .WithMany(u => u.CostCycles)
                .UsingEntity<Dictionary<string, object>>(
                    "CostCycleUnit",
                    j => j.HasOne<Unit>().WithMany().HasForeignKey("UnitsId").OnDelete(DeleteBehavior.NoAction),
                    j => j.HasOne<CostCycle>().WithMany().HasForeignKey("CostCyclesId").OnDelete(DeleteBehavior.Cascade));

            // Configure UnitCost relationships to avoid multiple cascade paths
            // UnitCost -> CostCycle (Cascade) and UnitCost -> Unit (NoAction)
            builder.Entity<UnitCost>()
                .HasOne(uc => uc.CostCycle)
                .WithMany()
                .HasForeignKey(uc => uc.CostCycleId)
                .OnDelete(DeleteBehavior.Cascade);

            builder.Entity<UnitCost>()
                .HasOne(uc => uc.Unit)
                .WithMany()
                .HasForeignKey(uc => uc.UnitId)
                .OnDelete(DeleteBehavior.NoAction);

            // ============================================================
            // Reference/Lookup tables: These have fixed, meaningful IDs
            // that are explicitly set in seed data and cross-referenced
            // by other entities. Identity auto-generation must be disabled.
            // ============================================================

            // Province: ProvinceId (1-31) are stable identifiers
            builder.Entity<Province>()
                .Property(p => p.ProvinceId)
                .ValueGeneratedNever();

            // City: CityId (101, 102, ...) are meaningful (provinceId * 100 + index)
            builder.Entity<City>()
                .Property(c => c.CityId)
                .ValueGeneratedNever();

            // BasicTable (base for TransactionType): Id (1,2) are fixed reference data
            builder.Entity<BasicTable>()
                .Property(b => b.Id)
                .ValueGeneratedNever();

            // IncomeCostTitle: Id (1-12) are fixed reference data
            builder.Entity<IncomeCostTitle>()
                .Property(i => i.Id)
                .ValueGeneratedNever();

            // UnitState: Id (1-5) are fixed reference data
            builder.Entity<UnitState>()
                .Property(u => u.Id)
                .ValueGeneratedNever();

            // Transaction: Seeder uses explicit IDs (1,2,3) that are
            // cross-referenced by UnitCost.TransactionId
            builder.Entity<Transaction>()
                .Property(t => t.Id)
                .ValueGeneratedNever();
        }


        public override int SaveChanges()
        {
            var modifiedEntries = ChangeTracker.Entries()
                .Where(p => p.State == EntityState.Modified ||
                p.State == EntityState.Added ||
                p.State == EntityState.Deleted
                );
            foreach (var item in modifiedEntries)
            {
                var entityType = item.Context.Model.FindEntityType(item.Entity.GetType());
                if (entityType != null)
                {
                    if (entityType.ClrType.GetCustomAttributes(typeof(AuditableAttribute), true).Length == 0)
                        continue;
                    var inserted = entityType.FindProperty("InsertTime");
                    var updated = entityType.FindProperty("UpdateTime");
                    var RemoveTime = entityType.FindProperty("RemoveTime");
                    var IsRemoved = entityType.FindProperty("IsRemoved");
                    if (item.State == EntityState.Added && inserted != null)
                    {
                        item.Property("InsertTime").CurrentValue = DateTime.Now;
                    }
                    if (item.State == EntityState.Modified && updated != null)
                    {
                        item.Property("UpdateTime").CurrentValue = DateTime.Now;
                    }

                    if (item.State == EntityState.Deleted && RemoveTime != null && IsRemoved != null)
                    {
                        item.Property("RemoveTime").CurrentValue = DateTime.Now;
                        item.Property("IsRemoved").CurrentValue = true;
                        item.State = EntityState.Modified;
                    }
                }

            }
            return base.SaveChanges();
        }

        //{
        //    var entries = ChangeTracker
        //        .Entries()
        //        .Where(e =>
        //                e.State == EntityState.Added
        //                || e.State == EntityState.Modified);

        //    foreach (var entityEntry in entries)
        //    {
        //        entityEntry.Property("UpdateTime").CurrentValue = DateTime.Now;

        //        if (entityEntry.State == EntityState.Added)
        //        {
        //            entityEntry.Property("InsertTime").CurrentValue = DateTime.Now;
        //        }
        //    }
        //    entries = ChangeTracker
        //        .Entries()
        //        .Where(e =>
        //                e.State == EntityState.Deleted);

        //    foreach (var entityEntry in entries)
        //    {
        //        entityEntry.State = EntityState.Modified;
        //        entityEntry.Property("RemoveTime").CurrentValue = DateTime.Now;
        //        entityEntry.Property("IsRemoved").CurrentValue = true;
        //    }

        //    return base.SaveChanges();
        //}
        public virtual DbSet<UnitState> UnitStates { get; set; }
        public virtual DbSet<Person> Persons { get; set; }
        public virtual DbSet<ComplexPerson> ComplexPersons { get; set; }
        public virtual DbSet<BasicTable> BasicTables { get; set; }
        public virtual DbSet<Chat> Chats { get; set; }
        public virtual DbSet<ComplexEntity> ComplexEntities { get; set; }
        public virtual DbSet<ComplexManager> ComplexManagers { get; set; }
        public virtual DbSet<ComplexUnitEvent> ComplexUnitEvents { get; set; }
        public virtual DbSet<Poster> Posters { get; set; }
        public virtual DbSet<Transaction> Transactions { get; set; }
        public virtual DbSet<IncomeCostTitle> IncomeCostTitles { get; set; }
        public virtual DbSet<TransactionType> TransactionTypes { get; set; }
        public virtual DbSet<Unit> Units { get; set; }
        public virtual DbSet<CostCycle> CostCycles { get; set; }
        public virtual DbSet<UnitCost> UnitCosts { get; set; }
        public virtual DbSet<UserToken> UserTokens { get; set; }
        public virtual DbSet<SmsCode> SmsCodes { get; set; }
        public virtual DbSet<Province> Provinces { get; set; }
        public virtual DbSet<City> Cities { get; set; }

        protected override void ConfigureConventions(ModelConfigurationBuilder builder)
        {

            builder.Properties<DateOnly>()
                .HaveConversion<DateOnlyConverter>()
                .HaveColumnType("date");

            base.ConfigureConventions(builder);

        }
    }
    public class DateOnlyConverter : ValueConverter<DateOnly, DateTime>
    {
        public DateOnlyConverter()
            : base(dateOnly =>
                    dateOnly.ToDateTime(TimeOnly.MinValue),
                dateTime => DateOnly.FromDateTime(dateTime))
        { }
    }
}