using System;
using System.Collections.Generic;
using System.IO;
using System.Linq;
using System.Net;
using System.Net.Http;
using System.Net.Http.Headers;
using System.Text;
using System.Web;
using System.Web.Http;

namespace ExportMap.cs
{
    public class WebUtils
    {
        #region LFData
        private static string _lfData;

        public static string LFData
        {
            get
            {
                if (string.IsNullOrEmpty(_lfData))
                {
                    _lfData = Tools.GetSetting("lfData");
                }

                return _lfData;
            }
        }
        #endregion

        /// <summary>
        /// 获取地形图层文件
        /// </summary>
        public static HttpResponseMessage GetLayerJson(HttpRequestMessage Request, string path)
        {
            string basePath = Path.Combine(LFData, path);
            if (!Directory.Exists(basePath))
            {
                throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.BadRequest, "路径不存在！"));
            }

            string file = basePath + "\\layer.json";
            if (!File.Exists(file))
            {
                throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.NotFound, "文件不存在！"));
            }

            return DownloadFile(file, "layer.json");
        }

        /// <summary>
        /// 获取地形文件
        /// </summary>
        public static HttpResponseMessage GetTerrain(HttpRequestMessage Request, string path, int z, int x, int y)
        {
            string basePath = Path.Combine(LFData, path);
            if (!Directory.Exists(basePath))
            {
                throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.BadRequest, "路径不存在！"));
            }

            string file = basePath + "\\" + z + "\\" + x + "\\" + y + ".terrain";
            if (!File.Exists(file))
            {
                throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.NotFound, "文件不存在！"));
            }

            return DownloadFile(file, y + ".terrain");
        }

        /// <summary>
        /// 获取地形文件，不存在返回空文件
        /// </summary>
        public static HttpResponseMessage GetTerrain0(HttpRequestMessage Request, string path, int z, int x, int y)
        {
            string basePath = Path.Combine(LFData, path);
            if (!Directory.Exists(basePath))
            {
                throw new HttpResponseException(Request.CreateResponse(HttpStatusCode.BadRequest, "路径不存在！"));
            }

            string file = basePath + "\\" + z + "\\" + x + "\\" + y + ".terrain";
            if (!File.Exists(file))
            {
                return DownloadFile(Tools.BaseDir + "\\Sources\\empty.terrain", y + ".terrain");
            }

            return DownloadFile(file, y + ".terrain");
        }

        /// <summary>
        /// 下载文件
        /// </summary>
        public static HttpResponseMessage DownloadFile(string file, string fileName)
        {
            //string fileName = Path.GetFileName(file);
            //FileStream stream = new FileStream(file, FileMode.Open);
            FileStream stream = File.OpenRead(file);

            HttpResponseMessage response = new HttpResponseMessage(HttpStatusCode.OK);
            response.Content = new StreamContent(stream);
            response.Content.Headers.ContentDisposition = new ContentDispositionHeaderValue("attachment");
            response.Content.Headers.ContentDisposition.FileName = HttpUtility.UrlEncode(fileName);
            response.Content.Headers.ContentType = new MediaTypeHeaderValue("application/octet-stream");

            //response.Content.Headers.Add("Cache-Control", "max-age=2592000"); // 缓存1个月
            response.Content.Headers.Expires = DateTimeOffset.Now.AddMonths(1); // new DateTimeOffset(DateTime.Now.AddMonths(1));

            return response;
        }

        /// <summary>
        /// Get请求
        /// </summary>
        public static string GetData(string url)
        {
            /*WebClient wc = new WebClient();
            Byte[] pageData = wc.DownloadData(url);

            Encoding coding = Encoding.GetEncoding("UTF-8");
            string str = coding.GetString(pageData);

            return str;*/

            Uri uri = new Uri(url);
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
            request.Method = "GET";
            request.ContentType = "application/x-www-form-urlencoded";

            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.UTF8);
            string str = reader.ReadToEnd();
            reader.Close();

            return str;
        }

        /// <summary>
        /// Post请求
        /// string data = string.Format("token={0}&f=json&where={1}", Token, "");
        /// </summary>
        public static string PostData(string url, string data)
        {
            Uri uri = new Uri(url);
            HttpWebRequest request = (HttpWebRequest)WebRequest.Create(uri);
            request.Method = "POST";
            request.ContentType = "application/x-www-form-urlencoded";

            if (data != null)
            {
                byte[] bytes = Encoding.UTF8.GetBytes(data);
                request.ContentLength = bytes.Length;
                Stream outstream = request.GetRequestStream();
                outstream.Write(bytes, 0, bytes.Length);
                outstream.Flush();
                outstream.Close();
            }

            HttpWebResponse response = (HttpWebResponse)request.GetResponse();
            StreamReader reader = new StreamReader(response.GetResponseStream(), Encoding.UTF8);
            string result = reader.ReadToEnd();
            reader.Close();

            return result;
        }
    }
}