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

namespace Laservall.Solidworks.Server.Handlers
{
    internal sealed class MatchMaterialHandler
    {
        private const string PlmApiUrl = "http://10.0.0.155:9991/api/PLM/FindPartsCode";
        private static readonly HttpClient _httpClient = new HttpClient { Timeout = TimeSpan.FromSeconds(30) };

        public async Task HandleMatch(HttpListenerContext context, CancellationToken ct)
        {
            string body;
            using (var reader = new StreamReader(context.Request.InputStream, Encoding.UTF8))
            {
                body = await reader.ReadToEndAsync();
            }

            var request = JsonConvert.DeserializeObject<MatchMaterialRequest>(body);
            if (request?.Items == null || request.Items.Count == 0)
            {
                await WriteJson(context.Response, new MatchMaterialResponse
                {
                    Success = true,
                    Results = new List<MatchMaterialResultDto>()
                }, ct);
                return;
            }

            try
            {
                var plmRequestBody = request.Items
                    .Select(i => new PlmFindPartsCodeRequest { model = i.DrawingNo })
                    .ToList();

                var plmJson = JsonConvert.SerializeObject(plmRequestBody);
                var httpContent = new StringContent(plmJson, Encoding.UTF8, "application/json-patch+json");
                var httpResponse = await _httpClient.PostAsync(PlmApiUrl, httpContent, ct);
                var responseText = await httpResponse.Content.ReadAsStringAsync();

                if (!httpResponse.IsSuccessStatusCode)
                {
                    await WriteJson(context.Response, new MatchMaterialResponse
                    {
                        Success = false,
                        Results = new List<MatchMaterialResultDto>(),
                        Error = $"PLM API 返回 {(int)httpResponse.StatusCode}: {responseText}"
                    }, ct);
                    return;
                }

                var plmResults = JsonConvert.DeserializeObject<List<PlmFindPartsCodeResponse>>(responseText)
                    ?? new List<PlmFindPartsCodeResponse>();

                var plmLookup = plmResults
                    .Where(r => !string.IsNullOrEmpty(r.part_code))
                    .ToDictionary(r => r.model ?? "", r => r, StringComparer.OrdinalIgnoreCase);

                var results = new List<MatchMaterialResultDto>();
                foreach (var item in request.Items)
                {
                    PlmFindPartsCodeResponse plmMatch;
                    if (plmLookup.TryGetValue(item.DrawingNo ?? "", out plmMatch))
                    {
                        results.Add(new MatchMaterialResultDto
                        {
                            DrawingNo = item.DrawingNo,
                            DocPath = item.DocPath,
                            PartCode = plmMatch.part_code,
                            PartName = plmMatch.part_name,
                            Matched = true
                        });
                    }
                    else
                    {
                        results.Add(new MatchMaterialResultDto
                        {
                            DrawingNo = item.DrawingNo,
                            DocPath = item.DocPath,
                            PartCode = "",
                            PartName = "",
                            Matched = false
                        });
                    }
                }

                await WriteJson(context.Response, new MatchMaterialResponse
                {
                    Success = true,
                    Results = results
                }, ct);
            }
            catch (Exception ex)
            {
                await WriteJson(context.Response, new MatchMaterialResponse
                {
                    Success = false,
                    Results = new List<MatchMaterialResultDto>(),
                    Error = $"匹配失败: {ex.Message}"
                }, ct);
            }
        }

        private static async Task WriteJson(HttpListenerResponse response, object data, CancellationToken ct)
        {
            response.ContentType = "application/json; charset=utf-8";
            string json = JsonConvert.SerializeObject(data);
            byte[] bytes = Encoding.UTF8.GetBytes(json);
            response.ContentLength64 = bytes.Length;
            await response.OutputStream.WriteAsync(bytes, 0, bytes.Length, ct);
            response.Close();
        }
    }
}