using Laservall.Solidworks.Model;
using Laservall.Solidworks.Server.Dto;
using Newtonsoft.Json;
using System;
using System.Collections.Generic;
using System.Linq;
using System.Net;
using System.Text;
using System.Threading;
using System.Threading.Tasks;

namespace Laservall.Solidworks.Server.Handlers
{
    internal sealed class BomDataHandler
    {
        private readonly IBomDataProvider _dataProvider;
        private BomLoadResult _lastLoadResult;

        public BomDataHandler(IBomDataProvider dataProvider)
        {
            _dataProvider = dataProvider;
        }

        public BomLoadResult LastLoadResult => _lastLoadResult;

        public async Task HandleGetData(HttpListenerContext context, CancellationToken ct)
        {
            try
            {
                var result = await _dataProvider.LoadBomAsync(null, ct);
                _lastLoadResult = result;

                var response = new BomStreamResponse
                {
                    Items = result.Items.Select(ToDto).ToList(),
                    DynamicKeys = result.DynamicKeys,
                    Settings = ToSettingsDto(result.Settings)
                };

                string json = JsonConvert.SerializeObject(response);
                byte[] bytes = Encoding.UTF8.GetBytes(json);

                context.Response.StatusCode = 200;
                context.Response.ContentType = "application/json; charset=utf-8";
                context.Response.ContentLength64 = bytes.Length;
                await context.Response.OutputStream.WriteAsync(bytes, 0, bytes.Length, ct);
                context.Response.Close();
            }
            catch (OperationCanceledException)
            {
                try { context.Response.Close(); } catch { }
            }
            catch (Exception ex)
            {
                try
                {
                    var errorResponse = new { error = ex.Message };
                    string errorJson = JsonConvert.SerializeObject(errorResponse);
                    byte[] errorBytes = Encoding.UTF8.GetBytes(errorJson);

                    context.Response.StatusCode = 500;
                    context.Response.ContentType = "application/json; charset=utf-8";
                    context.Response.ContentLength64 = errorBytes.Length;
                    await context.Response.OutputStream.WriteAsync(errorBytes, 0, errorBytes.Length, ct);
                    context.Response.Close();
                }
                catch { }
            }
        }

        private static BomItemDto ToDto(BomItemModel item)
        {
            return new BomItemDto
            {
                Level = item.Level,
                LevelDisplay = item.LevelDisplay,
                DrawingNo = item.DrawingNo,
                ConfigName = item.ConfigName,
                PartName = item.PartName,
                MaterialProp = item.MaterialProp,
                Material = item.Material,
                Classification = item.Classification,
                Quantity = item.Quantity,
                IsAssembly = item.IsAssembly,
                IsOutSourcing = item.IsOutSourcing,
                DocPath = item.DocPath,
                Props = item.Props ?? new Dictionary<string, string>(),
                HasChildren = item.HasChildren,
                NodeId = item.NodeId,
                ParentNodeId = item.ParentNodeId
            };
        }

        private static SettingsDto ToSettingsDto(BomSettings settings)
        {
            return new SettingsDto
            {
                Columns = settings.Columns.Select(c => new ColumnConfigDto
                {
                    Name = c.Name,
                    IsVisible = c.IsVisible,
                    IsExport = c.IsExport,
                    IsFixed = c.IsFixed,
                    IsUserAdded = c.IsUserAdded
                }).ToList(),
                RemovedKeys = settings.RemovedKeys?.ToList() ?? new List<string>()
            };
        }
    }
}