using System.Collections.Concurrent;
using System.Xml;

using Microsoft.OpenApi.Any;
using Microsoft.OpenApi.Interfaces;
using Microsoft.OpenApi.Models;

using Swashbuckle.AspNetCore.Swagger;

using VberZero;
using VberZero.Tools.StringModel;

namespace VberAdmin.Swagger
{
    /// <summary>
    /// swagger显示控制器的描述
    /// </summary>
    public class SwaggerControllerDescProvider : ISwaggerProvider
    {
        private readonly ISwaggerProvider _swaggerProvider;
        private static readonly ConcurrentDictionary<string, OpenApiDocument> _cache = new ConcurrentDictionary<string, OpenApiDocument>();
        private readonly string _xml;

        /// <summary>
        ///
        /// </summary>
        /// <param name="swaggerProvider"></param>
        /// <param name="xml">xml文档路径</param>
        public SwaggerControllerDescProvider(ISwaggerProvider swaggerProvider, string xml)
        {
            _swaggerProvider = swaggerProvider;
            _xml = xml;
        }

        public OpenApiDocument GetSwagger(string documentName, string host = null, string basePath = null)
        {
            var cacheKey = $"{documentName}";
            //只读取一次
            if (!_cache.TryGetValue(cacheKey, out var srcDoc))
            {
                srcDoc = _swaggerProvider.GetSwagger(documentName, host, basePath);

                srcDoc.ExternalDocs = GetControllerDoc();
                _cache.TryAdd(cacheKey, srcDoc);
            }
            return srcDoc;
        }

        public OpenApiExternalDocs GetControllerDoc()
        {
            string xmlPath = _xml;
            ConcurrentDictionary<string, IOpenApiExtension> controllerDescDict = new ConcurrentDictionary<string, IOpenApiExtension>();
            if (File.Exists(xmlPath))
            {
                XmlDocument xDoc = new XmlDocument();
                xDoc.Load(xmlPath);

                // ReSharper disable once PossibleNullReferenceException
                foreach (XmlNode node in xDoc.SelectNodes("//member"))
                {
                    if (node.Attributes != null)
                    {
                        var type = node.Attributes["name"]?.Value;
                        if (type != null && type.StartsWith("T:"))
                        {
                            //控制器
                            var arrPath = type.Split('.');
                            var length = arrPath.Length;
                            var controllerName = arrPath[length - 1];
                            string key = "";
                            var summaryNode = node.SelectSingleNode("summary");
                            if (controllerName.EndsWith("Controller"))
                            {
                                //获取控制器注释
                                int cCount = "Controller".Length;
                                key = controllerName.Remove(controllerName.Length - cCount, cCount);
                            }
                            else if (controllerName.EndsWith("AppService"))
                            {
                                //获取AppService注释
                                int cCount = "AppService".Length;
                                key = controllerName.Remove(controllerName.Length - cCount, cCount);
                            }
                            else if (controllerName.EndsWith("ApplicationService"))
                            {
                                //获取ApplicationService注释
                                int cCount = "ApplicationService".Length;
                                key = controllerName.Remove(controllerName.Length - cCount, cCount);
                            }

                            if (key.NotEmpty())
                            {
                                key = $"{VzConsts.AppApiName}95{key.Substring(0, 1).ToLowerInvariant() + key.Substring(1)}";
                                if (summaryNode != null && !string.IsNullOrEmpty(summaryNode.InnerText) && !controllerDescDict.ContainsKey(key))
                                {
                                    controllerDescDict.TryAdd(key, new OpenApiString(summaryNode.InnerText.Trim()));
                                }
                            }
                        }
                    }
                }
            }
            var doc = new OpenApiExternalDocs()
            {
                Extensions = controllerDescDict
            };

            return doc;
        }
    }
}