using AutoMapper;
using MagicCarpetContracts.DataModels;
using MagicCarpetContracts.Exceptions;
using MagicCarpetContracts.StoragesContracts;
using MagicCarpetDatabase.Models;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Text;
using System.Threading.Tasks;

namespace MagicCarpetDatabase.Implementations;

internal class EmployeeStorageContract : IEmployeeStorageContract
{
    private readonly MagicCarpetDbContext _dbContext;
    private readonly Mapper _mapper;

    public EmployeeStorageContract(MagicCarpetDbContext dbContext)
    {
        _dbContext = dbContext;
        var config = new MapperConfiguration(cfg =>
        {
            cfg.CreateMap<Employee, EmployeeDataModel>();
            cfg.CreateMap<EmployeeDataModel, Employee>();
        });
        _mapper = new Mapper(config);
    }

    public List<EmployeeDataModel> GetList(bool onlyActive = true, string? postId = null, DateTime? fromBirthDate = null, DateTime? toBirthDate = null,
        DateTime? fromEmploymentDate = null, DateTime? toEmploymentDate = null)
    {
        try
        {
            var query = _dbContext.Employees.AsQueryable();
            if (onlyActive)
            {
                query = query.Where(x => !x.IsDeleted);
            }
            if (postId is not null)
            {
                query = query.Where(x => x.PostId == postId);
            }
            if (fromBirthDate is not null && toBirthDate is not null)
            {
                query = query.Where(x => x.BirthDate >= fromBirthDate && x.BirthDate <= toBirthDate);
            }
            if (fromEmploymentDate is not null && toEmploymentDate is not null)
            {
                query = query.Where(x => x.EmploymentDate >= fromEmploymentDate && x.EmploymentDate <= toEmploymentDate);
            }
            return [.. query.Select(x => _mapper.Map<EmployeeDataModel>(x))];
        }
        catch (Exception ex)
        {
            _dbContext.ChangeTracker.Clear();
            throw new StorageException(ex);
        }
    }

    public EmployeeDataModel? GetElementById(string id)
    {
        try
        {
            return _mapper.Map<EmployeeDataModel>(GetEmployeeById(id));
        }
        catch (Exception ex)
        {
            _dbContext.ChangeTracker.Clear();
            throw new StorageException(ex);
        }
    }

    public EmployeeDataModel? GetElementByFIO(string fio)
    {
        try
        {
            return _mapper.Map<EmployeeDataModel>(_dbContext.Employees.FirstOrDefault(x => x.FIO == fio));
        }
        catch (Exception ex)
        {
            _dbContext.ChangeTracker.Clear();
            throw new StorageException(ex);
        }
    }
    public EmployeeDataModel? GetElementByEmail(string email)
    {
        try
        {
            return _mapper.Map<EmployeeDataModel>(_dbContext.Employees.FirstOrDefault(x => x.Email == email));
        }
        catch (Exception ex)
        {
            _dbContext.ChangeTracker.Clear();
            throw new StorageException(ex);
        }
    }

    public void AddElement(EmployeeDataModel workerDataModel)
    {
        try
        {
            _dbContext.Employees.Add(_mapper.Map<Employee>(workerDataModel));
            _dbContext.SaveChanges();
        }
        catch (InvalidOperationException ex) when (ex.TargetSite?.Name == "ThrowIdentityConflict")
        {
            _dbContext.ChangeTracker.Clear();
            throw new ElementExistsException("Id", workerDataModel.Id);
        }
        catch (Exception ex)
        {
            _dbContext.ChangeTracker.Clear();
            throw new StorageException(ex);
        }
    }

    public void UpdElement(EmployeeDataModel workerDataModel)
    {
        try
        {
            var element = GetEmployeeById(workerDataModel.Id) ?? throw new ElementNotFoundException(workerDataModel.Id);
            _dbContext.Employees.Update(_mapper.Map(workerDataModel, element));
            _dbContext.SaveChanges();
        }
        catch (ElementNotFoundException)
        {
            _dbContext.ChangeTracker.Clear();
            throw;
        }
        catch (Exception ex)
        {
            _dbContext.ChangeTracker.Clear();
            throw new StorageException(ex);
        }
    }

    public void DelElement(string id)
    {
        try
        {
            var element = GetEmployeeById(id) ?? throw new ElementNotFoundException(id);
            element.IsDeleted = true;
            _dbContext.SaveChanges();
        }
        catch (ElementNotFoundException)
        {
            _dbContext.ChangeTracker.Clear();
            throw;
        }
        catch (Exception ex)
        {
            _dbContext.ChangeTracker.Clear();
            throw new StorageException(ex);
        }
    }

    private Employee? GetEmployeeById(string id) => _dbContext.Employees.FirstOrDefault(x => x.Id == id && !x.IsDeleted);

    
}