using Microsoft.EntityFrameworkCore;
using Microsoft.EntityFrameworkCore.Infrastructure;
using Persistence.Models;
using System.Linq;

namespace Persistence.Repositories;
public abstract class AbstractChangeLogRepository<TEntity, TChangeLogDto, TDto> : IChangeLogRepository<TDto, TChangeLogDto>
    where TDto : class, new()
    where TEntity : class, IChangeLogAbstract
    where TChangeLogDto : ChangeLogDto<TDto>
{
    private readonly DbContext dbContext;

    protected AbstractChangeLogRepository(DbContext dbContext)
    {
        this.dbContext = dbContext;
    }

    public abstract TEntity Convert(TDto entity);
    public async Task<int> Clear(int idUser, TRequest request, CancellationToken token)
    {
        var updateTime = DateTimeOffset.UtcNow;

        //todo
        var query = BuildQuery(request);
        query = query.Where(e => e.Obsolete == null);

        var entitiesToDelete = await query.ToArrayAsync(token);

        foreach (var entity in entitiesToDelete)
        {
            entity.IdState = IChangeLogAbstract.IdCleared;
            entity.Obsolete = updateTime;
            entity.IdEditor = idUser;
        }

        var result = await SaveChangesWithExceptionHandling(token);
        return result;
    }

    public async Task<int> ClearAndInsertRange(int idUser, TRequest request, IEnumerable<TDto> dtos, CancellationToken token)
    {
        var result = 0;
        using var transaction = await dbContext.Database.BeginTransactionAsync(token);
        try
        {
            result += await Clear(idUser, request, token);
            result += await InsertRangeWithoutTransaction(idUser, dtos, token);

            await transaction.CommitAsync(token);
            return result;
        }
        catch
        {
            await transaction.RollbackAsync(token);
            throw;
        }
    }

    public Task<IEnumerable<TDto>> GetCurrent(TRequest request, CancellationToken token)
    {
        throw new NotImplementedException();
    }

    public Task<IEnumerable<DateOnly>> GetDatesChange(TRequest request, CancellationToken token)
    {
        throw new NotImplementedException();
    }

    public Task<IEnumerable<TDto>> GetGtDate(DateTimeOffset date, CancellationToken token)
    {
        throw new NotImplementedException();
    }

    public async Task<int> InsertRange(int idUser, IEnumerable<TDto> dtos, CancellationToken token)
    {
        this.dbContext.Set<TEntity>();
        var db = GetDataBase();
        using var transaction = db.BeginTransaction();
        try
        {
            var result = await InsertRangeWithoutTransaction(idUser, dtos, token);
            await transaction.CommitAsync(token);
            return result;
        }
        catch
        {
            await transaction.RollbackAsync(token);
            throw;
        }
    }

    protected abstract DatabaseFacade GetDataBase();

    public Task<int> MarkAsDeleted(int idUser, IEnumerable<int> ids, CancellationToken token)
    {
        throw new NotImplementedException();
    }

    public Task<int> UpdateOrInsertRange(int idUser, IEnumerable<TDto> dtos, CancellationToken token)
    {
        throw new NotImplementedException();
    }

    public Task<int> UpdateRange(int idUser, IEnumerable<TDto> dtos, CancellationToken token)
    {
        throw new NotImplementedException();
    }

    public Task<IEnumerable<TChangeLogDto>> GetChangeLogForDate(TRequest request, DateOnly? date, CancellationToken token)
    {
        throw new NotImplementedException();
    }

    private async Task<int> InsertRangeWithoutTransaction(int idUser, IEnumerable<TDto> dtos, CancellationToken token)
    {
        var result = 0;
        if (dtos.Any())
        {
            var entities = dtos.Select(Convert);
            var creation = DateTimeOffset.UtcNow;
            var dbSet = dbContext.Set<TEntity>();
            foreach (var entity in entities)
            {
                entity.Id = default;
                entity.IdAuthor = idUser;
                entity.Creation = creation;
                entity.IdState = IChangeLogAbstract.IdStateActual;
                entity.IdEditor = null;
                entity.IdPrevious = null;
                entity.Obsolete = null;
                dbSet.Add(entity);
            }

            result += await SaveChangesWithExceptionHandling(token);
        }

        return result;
    }

    private async Task<int> SaveChangesWithExceptionHandling(CancellationToken token)
    {
        var result = await dbContext.SaveChangesAsync(token);
        return result;
        //try
        //{
        //    var result = await dbContext.SaveChangesAsync(token);
        //    return result;
        //}
        //catch (DbUpdateException ex)
        //{
        //    if (ex.InnerException is PostgresException pgException)
        //        TryConvertPostgresExceptionToValidateException(pgException);
        //    throw;
        //}
    }



    //private static void TryConvertPostgresExceptionToValidateException(PostgresException pgException)
    //{
    //    if (pgException.SqlState == PostgresErrorCodes.ForeignKeyViolation)
    //        throw new ArgumentInvalidException("dtos", pgException.Message + "\r\n" + pgException.Detail);
    //}
}