/// <summary>
/// Gets the domains that match a specified uri, into a group of domains.
/// </summary>
/// <param name="domains">The group of domains.</param>
/// <param name="current">The uri, or null.</param>
/// <returns>The domains and their normalized uris, that match the specified uri.</returns>
internal static IEnumerable<DomainAndUri> DomainsForUri(Domain[] domains, Uri current)
{
var scheme = current == null ? Uri.UriSchemeHttp : current.Scheme;
return domains
.Where(d => !d.IsWildcard)
.Select(SanitizeForBackwardCompatibility)
.Select(d => new DomainAndUri(d, scheme))
.OrderByDescending(d => d.Uri.ToString());
}
/// <summary>
/// Finds the domain that best matches a specified uri, into a group of domains.
/// </summary>
/// <param name="domains">The group of domains.</param>
/// <param name="current">The uri, or null.</param>
/// <param name="filter">A function to filter the list of domains, if more than one applies, or <c>null</c>.</param>
/// <returns>The domain and its normalized uri, that best matches the specified uri.</returns>
/// <remarks>
/// <para>If more than one domain matches, then the <paramref name="filter"/> function is used to pick
/// the right one, unless it is <c>null</c>, in which case the method returns <c>null</c>.</para>
/// <para>The filter, if any, will be called only with a non-empty argument, and _must_ return something.</para>
/// </remarks>
internal static DomainAndUri DomainForUri(Domain[] domains, Uri current, Func<DomainAndUri[], DomainAndUri> filter = null)
{
// sanitize the list to have proper uris for comparison (scheme, path end with /)
// we need to end with / because example.com/foo cannot match example.com/foobar
// we need to order so example.com/foo matches before example.com/
var scheme = current == null ? Uri.UriSchemeHttp : current.Scheme;
var domainsAndUris = domains
.Where(d => !d.IsWildcard)
.Select(SanitizeForBackwardCompatibility)
.Select(d => new DomainAndUri(d, scheme))
.OrderByDescending(d => d.Uri.ToString())
.ToArray();
if (!domainsAndUris.Any())
return null;
DomainAndUri domainAndUri;
if (current == null)
{
// take the first one by default (what else can we do?)
domainAndUri = domainsAndUris.First(); // .First() protected by .Any() above
}
else
{
// look for the first domain that would be the base of the hint
var hintWithSlash = current.EndPathWithSlash();
domainAndUri = domainsAndUris
.FirstOrDefault(d => d.Uri.EndPathWithSlash().IsBaseOf(hintWithSlash));
// if none matches, then try to run the filter to pick a domain
if (domainAndUri == null && filter != null)
{
domainAndUri = filter(domainsAndUris);
// if still nothing, pick the first one?
// no: move that constraint to the filter, but check
if (domainAndUri == null)
throw new InvalidOperationException("The filter returned null.");
}
}
return domainAndUri;
}
