using FluentValidation;
using Microsoft.EntityFrameworkCore;
using Somnia.GuestLog.Enums.Services;
using Somnia.GuestLog.Infrastructure;
using Somnia.GuestLog.Models;
using Somnia.GuestLog.Models.DTOs;
using Somnia.GuestLog.Models.Entities;
using Somnia.GuestLog.Utils;

namespace Somnia.GuestLog.Services.Entity;

public class StayExportFileEntityService(
    ILogger<StayExportFileEntityService> logger,
    IDbContextFactory<GuestLogContext> contextFactory
) : IStayExportFileEntityService
{
    public async Task<Result> CreateStayExportAsync(StayExportFileDTO dto)
    {
        ArgumentNullException.ThrowIfNull(dto, nameof(dto));

        //Check for null values in the DTO.
        if (dto.ExportFormat == null || dto.ExportResult == null || dto.ExportTime == null)
        {
            throw new InvalidOperationException("StayExportFile dto contains null fields");
        }

        if (dto.ExportParams == null)
        {
            throw new InvalidOperationException("StayExportFile dto contains null ExportParams");
        }

        StayExportParams exportParams = GetExportParamsFromDTO(dto.ExportParams);
        StayExportFile dbItem = new()
        {
            ExportFormat = dto.ExportFormat.Value,
            ExportParams = exportParams,
            ExportResult = dto.ExportResult.Value,
            ExportedPath = dto.ExportedPath,
            ExportTime = dto.ExportTime?.ToUniversalTime() ?? DateTime.UtcNow,
        };

        try
        {
            using var dbContext = contextFactory.CreateDbContext();
            await dbContext.AddAsync(dbItem);
            await dbContext.SaveChangesAsync();

            logger.LogInformation("StayExportFileService - CreateStayExportAsync: GuestDocument Created: '{id}'", dbItem.GetFullKey());
            return Result.Ok();
        }
        catch (Exception ex)
        {
            logger.LogError(ex, "StayExportFileService - CreateStayExportAsync: Error creating GuestDocument");
            return Result.FailUnknownError();
        }
    }

    public Task<Result> UpdateStayExportAsync(StayExportFileDTO dto)
    {
        throw new NotImplementedException();
    }

    public async Task<Result> DeleteStayExportAsync(StayExportFileDTO dto)
    {
        try
        {
            using var dbContext = contextFactory.CreateDbContext();

            int deletedCount = await dbContext.StayExportFiles
                .Where(e => e.Id == dto.Id)
                .ExecuteDeleteAsync();

            if (deletedCount == 0)
            {
                logger.LogWarning("StayExportFileService - DeleteStayExportAsync: Error deleting StayExport. Entity not found with ID: '{ID}'", dto.Id);
                return Result.Fail(ResultCode.NotFound);
            }

            logger.LogInformation(
                "StayExportFileService - DeleteStayExportAsync: StayExport deleted with Id: '{id}'.", dto.Id);
            return Result.Ok();
        }
        catch (Exception ex)
        {
            logger.LogError(ex, "StayExportFileService - DeleteStayExportAsync: Error creating GuestDocument");
            return Result.FailUnknownError();
        }
    }


    public async Task<StayExportFileDTO?> GetDtoByIdAsync(long id)
    {
        using var dbContext = contextFactory.CreateDbContext();
        StayExportFile? dbItem = await dbContext.StayExportFiles
            .Where(e => e.Id == id)
            .FirstOrDefaultAsync();

        return dbItem is not null ? GetDtoFromDb(dbItem) : null;
    }

    public async Task<IEnumerable<StayExportFileDTO>> GetDtoListAsync(int limit = 0)
    {
        using var dbContext = contextFactory.CreateDbContext();

        IQueryable<StayExportFile> query = dbContext.StayExportFiles
            .OrderByDescending(e => e.ExportTime)
            .WithLimit(limit);

        var dbList = await query.ToListAsync();

        return dbList.Select(e => GetDtoFromDb(e));
    }


    #region Internal Methods

    private static StayExportFileDTO GetDtoFromDb(StayExportFile dbItem)
    {
        return EntityMapping.MapStayExportFileEntityToDTO(dbItem);
    }

    private static StayExportParams GetExportParamsFromDTO(StayExportParamsDTO dto)
    {
        if (dto.ExportType == null)
        {
            throw new InvalidOperationException("Dto with invalid data");
        }

        return new()
        {
            ExportType = dto.ExportType.Value,
            ExportPeriodStart = dto.ExportPeriodStart?.ToUniversalTime(),
            ExportPeriodEnd = dto.ExportPeriodEnd?.ToUniversalTime()
        };
    }

    #endregion
}