// Copyright (C) 2010 Google Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
package com.google.caja.plugin;
import com.google.caja.lexer.ExternalReference;
import java.io.File;
import java.net.URI;
import java.net.URISyntaxException;
import java.util.Map;
final class FileSystemUriPolicy implements UriPolicy {
private final UriToFile uriToFile;
FileSystemUriPolicy(UriToFile uriToFile) { this.uriToFile = uriToFile; }
/** Return a new URI with a different fragment. */
private static URI refragUri(URI uri, String frag) throws URISyntaxException {
return new URI(uri.getScheme(), uri.getSchemeSpecificPart(), frag);
}
public String rewriteUri(
ExternalReference u, UriEffect effect, LoaderType loader,
Map<String, ?> hints) {
URI uri = u.getUri();
try {
URI fragless = refragUri(uri, null);
// allow uri references within the base directory
File f = uriToFile.apply(fragless);
if (f != null) {
URI base = new File(uriToFile.directory, ".").toURI();
URI rel = base.relativize(fragless);
return refragUri(rel, uri.getFragment()).toString();
}
// allow bare fragments
URI self = u.getReferencePosition().source().getUri();
String uristr = self.relativize(uri).toString();
if (uristr.startsWith("#")) { return uristr; }
} catch (URISyntaxException e) {
// return null below
}
// denied
return null;
}
}