using AutoMapper;
using CatHasPawsContratcs.DataModels;
using CatHasPawsContratcs.Exceptions;
using CatHasPawsContratcs.Resources;
using CatHasPawsContratcs.StoragesContracts;
using CatHasPawsDatabase.Models;
using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Localization;
using Npgsql;

namespace CatHasPawsDatabase.Implementations;

internal class PostStorageContract : IPostStorageContract
{
	private readonly CatHasPawsDbContext _dbContext;
	private readonly Mapper _mapper;
	private readonly IStringLocalizer<Messages> _localizer;

	public PostStorageContract(CatHasPawsDbContext dbContext, IStringLocalizer<Messages> localizer)
	{
		_dbContext = dbContext;
		var config = new MapperConfiguration(cfg =>
		{
			cfg.CreateMap<Post, PostDataModel>()
				.ForMember(x => x.Id, x => x.MapFrom(src => src.PostId));
			cfg.CreateMap<PostDataModel, Post>()
				.ForMember(x => x.Id, x => x.Ignore())
				.ForMember(x => x.PostId, x => x.MapFrom(src => src.Id))
				.ForMember(x => x.IsActual, x => x.MapFrom(src => true))
				.ForMember(x => x.ChangeDate, x => x.MapFrom(src => DateTime.UtcNow))
				.ForMember(x => x.Configuration, x => x.MapFrom(src => src.ConfigurationModel));
		});
		_mapper = new Mapper(config);
		_localizer = localizer;
	}

	public List<PostDataModel> GetList()
	{
		try
		{
			return [.. _dbContext.Posts.Select(x => _mapper.Map<PostDataModel>(x))];
		}
		catch (Exception ex)
		{
			_dbContext.ChangeTracker.Clear();
			throw new StorageException(ex, _localizer);
		}
	}

	public List<PostDataModel> GetPostWithHistory(string postId)
	{
		try
		{
			return [.. _dbContext.Posts.Where(x => x.PostId == postId).Select(x => _mapper.Map<PostDataModel>(x))];
		}
		catch (Exception ex)
		{
			_dbContext.ChangeTracker.Clear();
			throw new StorageException(ex, _localizer);
		}
	}

	public PostDataModel? GetElementById(string id)
	{
		try
		{
			return _mapper.Map<PostDataModel>(_dbContext.Posts.FirstOrDefault(x => x.PostId == id && x.IsActual));
		}
		catch (Exception ex)
		{
			_dbContext.ChangeTracker.Clear();
			throw new StorageException(ex, _localizer);
		}
	}

	public PostDataModel? GetElementByName(string name)
	{
		try
		{
			return _mapper.Map<PostDataModel>(_dbContext.Posts.FirstOrDefault(x => x.PostName == name && x.IsActual));
		}
		catch (Exception ex)
		{
			_dbContext.ChangeTracker.Clear();
			throw new StorageException(ex, _localizer);
		}
	}

	public void AddElement(PostDataModel postDataModel)
	{
		try
		{
			_dbContext.Posts.Add(_mapper.Map<Post>(postDataModel));
			_dbContext.SaveChanges();
		}
		catch (DbUpdateException ex) when (ex.InnerException is PostgresException { ConstraintName: "IX_Posts_PostName_IsActual" })
		{
			_dbContext.ChangeTracker.Clear();
			throw new ElementExistsException("PostName", postDataModel.PostName, _localizer);
		}
		catch (DbUpdateException ex) when (ex.InnerException is PostgresException { ConstraintName: "IX_Posts_PostId_IsActual" })
		{
			_dbContext.ChangeTracker.Clear();
			throw new ElementExistsException("PostId", postDataModel.Id, _localizer);
		}
		catch (Exception ex)
		{
			_dbContext.ChangeTracker.Clear();
			throw new StorageException(ex, _localizer);
		}
	}

	public void UpdElement(PostDataModel postDataModel)
	{
		try
		{
			var transaction = _dbContext.Database.BeginTransaction();
			try
			{
				var element = GetPostById(postDataModel.Id) ?? throw new ElementNotFoundException(postDataModel.Id, _localizer);
				if (!element.IsActual)
				{
					throw new ElementDeletedException(postDataModel.Id, _localizer);
				}
				element.IsActual = false;
				_dbContext.SaveChanges();
				var newElement = _mapper.Map<Post>(postDataModel);
				_dbContext.Posts.Add(newElement);
				_dbContext.SaveChanges();
				transaction.Commit();
			}
			catch
			{
				transaction.Rollback();
				throw;
			}
		}
		catch (DbUpdateException ex) when (ex.InnerException is PostgresException { ConstraintName: "IX_Posts_PostName_IsActual" })
		{
			_dbContext.ChangeTracker.Clear();
			throw new ElementExistsException("PostName", postDataModel.PostName, _localizer);
		}
		catch (Exception ex) when (ex is ElementDeletedException || ex is ElementNotFoundException)
		{
			_dbContext.ChangeTracker.Clear();
			throw;
		}
		catch (Exception ex)
		{
			_dbContext.ChangeTracker.Clear();
			throw new StorageException(ex, _localizer);
		}
	}

	public void DelElement(string id)
	{
		try
		{
			var element = GetPostById(id) ?? throw new ElementNotFoundException(id, _localizer);
			if (!element.IsActual)
			{
				throw new ElementDeletedException(id, _localizer);
			}
			element.IsActual = false;
			_dbContext.SaveChanges();
		}
		catch
		{
			_dbContext.ChangeTracker.Clear();
			throw;
		}
	}

	public void ResElement(string id)
	{
		try
		{
			var element = GetPostById(id) ?? throw new ElementNotFoundException(id, _localizer);
			element.IsActual = true;
			_dbContext.SaveChanges();
		}
		catch
		{
			_dbContext.ChangeTracker.Clear();
			throw;
		}
	}

	private Post? GetPostById(string id) => _dbContext.Posts.Where(x => x.PostId == id).OrderByDescending(x => x.ChangeDate).FirstOrDefault();
}