OpenTween/Thumbnail/Services/FoursquareCheckin.cs

   1 // OpenTween - Client of Twitter
   2 // Copyright (c) 2012 kim_upsilon (@kim_upsilon) <https://upsilo.net/~upsilon/>
   3 // All rights reserved.
   4 //
   5 // This file is part of OpenTween.
   6 //
   7 // This program is free software; you can redistribute it and/or modify it
   8 // under the terms of the GNU General Public License as published by the Free
   9 // Software Foundation; either version 3 of the License, or (at your option)
  10 // any later version.
  11 //
  12 // This program is distributed in the hope that it will be useful, but
  13 // WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
  14 // or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
  15 // for more details.
  16 //
  17 // You should have received a copy of the GNU General Public License along
  18 // with this program. If not, see <http://www.gnu.org/licenses/>, or write to
  19 // the Free Software Foundation, Inc., 51 Franklin Street - Fifth Floor,
  20 // Boston, MA 02110-1301, USA.
  21
  22 using System;
  23 using System.Net.Http;
  24 using System.Runtime.Serialization.Json;
  25 using System.Text.RegularExpressions;
  26 using System.Threading;
  27 using System.Threading.Tasks;
  28 using System.Web;
  29 using System.Xml;
  30 using System.Xml.Linq;
  31 using System.Xml.XPath;
  32
  33 namespace OpenTween.Thumbnail.Services
  34 {
  35     class FoursquareCheckin : IThumbnailService
  36     {
  37         public static readonly Regex UrlPatternRegex =
  38             new Regex(@"^https?://foursquare\.com/.+?/checkin/(?<checkin_id>[0-9a-z]+)(?:\?s=(?<signature>[^&]+))?");
  39
  40         public static readonly string ApiBase = "https://api.foursquare.com/v2";
  41
  42         protected readonly HttpClient http;
  43
  44         public FoursquareCheckin()
  45             : this(null)
  46         {
  47         }
  48
  49         public FoursquareCheckin(HttpClient http)
  50         {
  51             this.http = http ?? MyCommon.CreateHttpClient();
  52         }
  53
  54         public override async Task<ThumbnailInfo> GetThumbnailInfoAsync(string url, PostClass post, CancellationToken token)
  55         {
  56             if (!AppendSettingDialog.Instance.IsPreviewFoursquare)
  57                 return null;
  58
  59             // ツイートに位置情報が付与されている場合は何もしない
  60             if (post.PostGeo.Lat != 0 || post.PostGeo.Lng != 0)
  61                 return null;
  62
  63             var match = UrlPatternRegex.Match(url);
  64
  65             if (!match.Success)
  66                 return null;
  67
  68             var checkinIdGroup = match.Groups["checkin_id"];
  69             var signatureGroup = match.Groups["signature"];
  70
  71             try
  72             {
  73                 // Foursquare のベニュー情報を取得
  74                 // 参照: https://developer.foursquare.com/docs/venues/venues
  75
  76                 var query = HttpUtility.ParseQueryString(string.Empty);
  77                 query["client_id"] = ApplicationSettings.FoursquareClientId;
  78                 query["client_secret"] = ApplicationSettings.FoursquareClientSecret;
  79                 query["v"] = "20140419"; // https://developer.foursquare.com/overview/versioning
  80
  81                 if (signatureGroup.Success)
  82                     query["signature"] = signatureGroup.Value;
  83
  84                 var apiUrl = new Uri(ApiBase + "/checkins/" + checkinIdGroup.Value + "?" + query);
  85
  86                 using (var response = await this.http.GetAsync(apiUrl, token).ConfigureAwait(false))
  87                 {
  88                     response.EnsureSuccessStatusCode();
  89
  90                     var jsonBytes = await response.Content.ReadAsByteArrayAsync()
  91                         .ConfigureAwait(false);
  92
  93                     var location = ParseIntoLocation(jsonBytes);
  94                     if (location == null)
  95                         return null;
  96
  97                     var map = MapThumb.GetDefaultInstance();
  98
  99                     return new ThumbnailInfo(this.http)
 100                     {
 101                         ImageUrl = map.CreateMapLinkUrl(location.Latitude, location.Longitude),
 102                         ThumbnailUrl = map.CreateStaticMapUrl(location.Latitude, location.Longitude),
 103                         TooltipText = null,
 104                     };
 105                 }
 106             }
 107             catch (HttpRequestException) { }
 108
 109             return null;
 110         }
 111
 112         internal static GlobalLocation ParseIntoLocation(byte[] jsonBytes)
 113         {
 114             using (var jsonReader = JsonReaderWriterFactory.CreateJsonReader(jsonBytes, XmlDictionaryReaderQuotas.Max))
 115             {
 116                 var xElm = XElement.Load(jsonReader);
 117
 118                 var locationElm = xElm.XPathSelectElement("/response/checkin/venue/location");
 119
 120                 // 座標が得られなかった場合
 121                 if (locationElm == null)
 122                     return null;
 123
 124                 // 月など、地球以外の星の座標である場合
 125                 var planetElm = locationElm.Element("planet");
 126                 if (planetElm != null && planetElm.Value != "earth")
 127                     return null;
 128
 129                 return new GlobalLocation
 130                 {
 131                     Latitude = double.Parse(locationElm.Element("lat").Value),
 132                     Longitude = double.Parse(locationElm.Element("lng").Value),
 133                 };
 134             }
 135         }
 136     }
 137 }