static string FormatEntry(Z0rEntry entry)
{
var ret = new StringBuilder();
ret.AppendFormat(CultureInfo.InvariantCulture, "z0r #{0}", entry.Z0rID);
if (entry.Artist != null || entry.Song != null || entry.Image != null)
{
ret.Append(" (");
if (entry.Artist != null && entry.Song != null)
{
ret.AppendFormat("{0} - {1}", entry.Artist, entry.Song);
}
else if (entry.Song != null)
{
ret.AppendFormat("{0}", entry.Song);
}
else if (entry.Artist != null)
{
ret.AppendFormat("{0} - ?", entry.Artist);
}
else
{
ret.Append("?");
}
ret.Append(" // ");
ret.Append(entry.Image != null ? entry.Image : "?");
ret.Append(")");
}
return(ret.ToString());
}
void LoadFromPage(long page)
{
var pageUri = new Uri(string.Format(CultureInfo.InvariantCulture, Z0rIndexUriFormat, page));
byte[] indexPageBytes;
using (var client = new HttpClient())
using (var request = new HttpRequestMessage(HttpMethod.Get, pageUri))
{
client.Timeout = TimeSpan.FromSeconds(LinkInfoConfig.TimeoutSeconds);
request.Headers.UserAgent.TryParseAdd(LinkInfoConfig.FakeUserAgent);
using (var response = client.SendAsync(request, HttpCompletionOption.ResponseHeadersRead).SyncWait())
{
indexPageBytes = response.Content.ReadAsByteArrayAsync().SyncWait();
}
}
string indexPageString = EncodingGuesser.GuessEncodingAndDecode(indexPageBytes, null);
var htmlDoc = new HtmlDocument();
htmlDoc.LoadHtml(indexPageString);
HtmlNode indexTable = htmlDoc.GetElementbyId("zebra");
IEnumerable <HtmlNode> foundRows = indexTable
.SelectNodes(".//tr")
.OfType <HtmlNode>();
foreach (HtmlNode foundRow in foundRows)
{
List <HtmlNode> cells = foundRow
.ChildNodes
.OfType <HtmlNode>()
.Where(n => n.Name == "th")
.ToList();
if (cells.Count != 5)
{
continue;
}
string idString = TrimmedInnerTextOrNull(cells[0]);
long id;
if (!long.TryParse(idString, NumberStyles.None, CultureInfo.InvariantCulture, out id))
{
continue;
}
string artist = TrimmedInnerTextOrNull(cells[1]);
string song = TrimmedInnerTextOrNull(cells[2]);
string image = TrimmedInnerTextOrNull(cells[3]);
string tag = TrimmedInnerTextOrNull(cells[4]);
EntryCache[id] = new Z0rEntry(id, artist, song, image, tag);
}
}
public LinkAndInfo ResolveLink(LinkToResolve link)
{
string absoluteUri = link.Link.AbsoluteUri;
Match z0rMatch = Z0rUrlPattern.Match(absoluteUri);
if (!z0rMatch.Success)
{
// can't handle this
return(null);
}
// obtain the ID
long z0rID;
if (!long.TryParse(z0rMatch.Groups["id"].Value, NumberStyles.None, CultureInfo.InvariantCulture, out z0rID))
{
// unparseable ID, probably too many digits
return(null);
}
Z0rEntry entry;
if (EntryCache.TryGetValue(z0rID, out entry))
{
// fast-path
return(link.ToResult(FetchErrorLevel.Success, FormatEntry(entry)));
}
Z0rRange range = RangeForID(z0rID);
if (!MaxPage.HasValue)
{
MaxPage = ObtainMaxPageValue();
}
if (!MaxPage.HasValue)
{
// bad
return(link.ToResult(
FetchErrorLevel.TransientError,
string.Format(CultureInfo.InvariantCulture, "z0r #{0}; fetching index page list failed", z0rID)
));
}
if (range.Page > MaxPage)
{
// the index does not contain this page
entry = new Z0rEntry(z0rID, null, null, null, null);
return(link.ToResult(FetchErrorLevel.Success, FormatEntry(entry)));
}
LoadFromPage(range.Page);
if (EntryCache.TryGetValue(z0rID, out entry))
{
return(link.ToResult(FetchErrorLevel.Success, FormatEntry(entry)));
}
return(link.ToResult(
FetchErrorLevel.TransientError,
string.Format(CultureInfo.InvariantCulture, "z0r #{0}; fetching failed", z0rID)
));
}