using Swashbuckle.Swagger;
using System.Collections.Concurrent;
using System.Collections.Generic;
using System.IO;
using System.Web.Http.Description;
using System.Xml;

namespace UFIDA.U8.Framework.Api
{
    /// <inheritdoc />
    public class SwaggerCacheProvider : ISwaggerProvider
    {
        private readonly ISwaggerProvider _swaggerProvider;
        private static readonly ConcurrentDictionary<string, SwaggerDocument> _cache = new ConcurrentDictionary<string, SwaggerDocument>();
        private readonly string _xmlPath;

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

        /// <inheritdoc />
        public SwaggerDocument GetSwagger(string rootUrl, string apiVersion)
        {
            var cacheKey = $"{rootUrl}_{apiVersion}";
            //只读取一次
            if (!_cache.TryGetValue(cacheKey, out var srcDoc))
            {
                srcDoc = _swaggerProvider.GetSwagger(rootUrl, apiVersion);

                srcDoc.vendorExtensions = new Dictionary<string, object>
            {
                { "ControllerDesc", GetControllerDesc() }
            };
                _cache.TryAdd(cacheKey, srcDoc);
            }
            return srcDoc;
        }

        /// <summary>
        /// 从API文档中读取控制器描述
        /// </summary>
        /// <returns>所有控制器描述</returns>
        public ConcurrentDictionary<string, string> GetControllerDesc()
        {
            var controllerDescDict = new ConcurrentDictionary<string, string>();
            if (File.Exists(_xmlPath))
            {
                var xmldoc = new XmlDocument();
                xmldoc.Load(_xmlPath);

                var cCount = "Controller".Length;
                var nodes = xmldoc.SelectNodes("//member");
                if (nodes == null || nodes.Count <= 0)
                    return null;

                foreach (XmlNode node in nodes)
                {
                    var type = node.Attributes?["name"].Value;
                    if (type != null && !type.StartsWith("T:")) continue;
                    var arrPath = type?.Split('.');
                    var controllerName = arrPath?[arrPath.Length - 1];
                    if (controllerName != null && controllerName.EndsWith("Controller"))  //控制器
                    {
                        //获取控制器注释
                        var summaryNode = node.SelectSingleNode("summary");
                        var key = controllerName.Remove(controllerName.Length - cCount, cCount);
                        if (summaryNode != null && !string.IsNullOrEmpty(summaryNode.InnerText) && !controllerDescDict.ContainsKey(key))
                        {
                            controllerDescDict.TryAdd(key, summaryNode.InnerText.Trim());
                        }
                    }
                }
            }
            return controllerDescDict;
        }
    }

    /// <inheritdoc />
    public class TokenRequiredHeaderParameter : IOperationFilter
    {
        /// <summary>
        /// 参数名称
        /// </summary>
        public static string HeaderKey { get; set; }
        /// <summary>
        /// 参数说明
        /// </summary>
        public static string Description { get; set; }

        /// <inheritdoc />
        public void Apply(Operation operation, SchemaRegistry schemaRegistry, ApiDescription apiDescription)
        {
            if (operation.parameters == null)
                operation.parameters = new List<Parameter>();
            operation.parameters.Add(new Parameter
            {
                name = HeaderKey,
                required = false,
                description = Description,
                type = "string",
                @in = "header"
            });
        }
    }
}