using AutoMapper;
using DMS.Application.DTOs;
using DMS.Application.Interfaces;
using DMS.Application.Interfaces.Database;
using DMS.Core.Enums;
using DMS.Core.Interfaces;
using DMS.Core.Models;

namespace DMS.Application.Services.Database
{
    /// <summary>
    /// 变量表应用服务，负责处理变量表相关的业务逻辑。
    /// 实现 <see cref="IVariableTableAppService"/> 接口。
    /// </summary>
    public class VariableTableAppService : IVariableTableAppService
    {
        private readonly IRepositoryManager _repositoryManager;
        private readonly IAppDataService _appDataService;
        private readonly IMapper _mapper;

        /// <summary>
        /// 构造函数，注入仓储管理器和AutoMapper。
        /// </summary>
        /// <param name="repositoryManager">仓储管理器实例。</param>
        /// <param name="mapper">AutoMapper 实例。</param>
        public VariableTableAppService(IRepositoryManager repositoryManager, IAppDataService appDataService, IMapper mapper)
        {
            _repositoryManager = repositoryManager;
            _appDataService = appDataService;
            _mapper = mapper;
        }

        /// <summary>
        /// 异步根据ID获取变量表。
        /// </summary>
        /// <param name="id">变量表ID。</param>
        /// <returns>变量表数据传输对象。</returns>
        public async Task<VariableTable> GetVariableTableByIdAsync(int id)
        {
            var variableTable = await _repositoryManager.VariableTables.GetByIdAsync(id);
            return _mapper.Map<VariableTable>(variableTable);
        }

        /// <summary>
        /// 异步获取所有变量表。
        /// </summary>
        /// <returns>变量表数据传输对象列表。</returns>
        public async Task<List<VariableTable>> GetAllVariableTablesAsync()
        {
            var variableTables = await _repositoryManager.VariableTables.GetAllAsync();
            return _mapper.Map<List<VariableTable>>(variableTables);
        }

        /// <summary>
        /// 异步创建变量表，并可选择性地创建关联菜单。
        /// </summary>
        /// <param name="createDto">包含变量表和菜单信息的创建数据传输对象。</param>
        /// <returns>创建后的变量表数据传输对象。</returns>
        /// <exception cref="ApplicationException">如果添加变量表失败或找不到设备菜单。</exception>
        public async Task<CreateVariableTableWithMenuDto> AddAsync(CreateVariableTableWithMenuDto createDto)
        {
            await _repositoryManager.BeginTranAsync();
            try
            {

                createDto.VariableTable = await _repositoryManager.VariableTables.AddAsync(createDto.VariableTable);
                if (createDto.VariableTable.Id == 0)
                {
                    throw new ApplicationException($"添加变量表失败，设备ID:{createDto.VariableTable.DeviceId},请检查。");
                }

                if (createDto.Menu is not null)
                {
                    createDto.Menu.TargetId = createDto.VariableTable.Id;
                    //映射菜单实体并设置关联信息
                    createDto.Menu = await _repositoryManager.Menus.AddAsync(createDto.Menu);
                }

                await _repositoryManager.CommitAsync();

                return createDto;
            }
            catch
            {
                await _repositoryManager.RollbackAsync();
                throw;
            }
        }

        /// <summary>
        /// 异步更新变量表。
        /// </summary>
        /// <param name="variableTable">要更新的变量表数据传输对象。</param>
        /// <returns>受影响的行数。</returns>
        /// <exception cref="ApplicationException">如果找不到变量表。</exception>
        public async Task<int> UpdateAsync(VariableTable variableTable)
        {

            int res = await _repositoryManager.VariableTables.UpdateAsync(variableTable);

            // 更新关联的菜单树
            var menu = _appDataService.Menus.Values.FirstOrDefault(m => m.MenuType == MenuType.VariableTableMenu && m.TargetId == variableTable.Id);
            if (menu is not null && variableTable.Name!= menu.Header)
            {
                menu.Header = variableTable.Name;
                // 更新关联的菜单树
                await _repositoryManager.Menus.UpdateAsync(menu);
            }

            return res;
        }

        /// <summary>
        /// 异步根据ID删除变量表，包括其关联的变量、MQTT别名和菜单（事务性操作）。
        /// </summary>
        /// <param name="id">要删除的变量表ID。</param>
        /// <returns>如果删除成功则为 true，否则为 false。</returns>
        /// <exception cref="InvalidOperationException">如果删除变量表失败。</exception>
        /// <exception cref="ApplicationException">如果删除变量表时发生其他错误。</exception>
        public async Task<bool> DeleteAsync(VariableTable variableTable)
        {
            try
            {
                await _repositoryManager.BeginTranAsync();
                var delRes = await _repositoryManager.VariableTables.DeleteAsync(variableTable);

                // 删除关联的菜单树
                var menu = _appDataService.Menus.Values.FirstOrDefault(m => m.MenuType == MenuType.VariableTableMenu && m.TargetId == variableTable.Id);
                if (menu is not null)
                {
                    // 删除关联的菜单树
                    await _repositoryManager.Menus.DeleteAsync(menu);
                }

                await _repositoryManager.CommitAsync();
                return true;
            }
            catch (Exception ex)
            {
                await _repositoryManager.RollbackAsync();
                // 可以在此记录日志
                throw new ApplicationException($"删除变量表时发生错误，操作已回滚,错误信息:{ex.Message}", ex);
            }
        }
    }
}