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/* -*- Mode: Java; c-basic-offset: 4; tab-width: 20; indent-tabs-mode: nil; -*-
* This Source Code Form is subject to the terms of the Mozilla Public
* License, v. 2.0. If a copy of the MPL was not distributed with this
package org.mozilla.focus.search;
import android.content.res.AssetManager;
import android.graphics.BitmapFactory;
import android.net.Uri;
import androidx.annotation.VisibleForTesting;
import android.util.Base64;
import org.xmlpull.v1.XmlPullParser;
import org.xmlpull.v1.XmlPullParserException;
import org.xmlpull.v1.XmlPullParserFactory;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.nio.charset.StandardCharsets;
/**
* A very simple parser for search plugins.
*/
/* package */ class SearchEngineParser {
private static final String URLTYPE_SEARCH_HTML = "text/html";
private static final String URL_REL_MOBILE = "mobile";
private static final String IMAGE_URI_PREFIX = "data:image/png;base64,";
public static SearchEngine load(AssetManager assetManager, String identifier, String path) throws IOException {
try (final InputStream stream = assetManager.open(path)) {
return load(identifier, stream);
} catch (XmlPullParserException e) {
throw new AssertionError("Parser exception while reading " + path, e);
}
}
/* package */ @VisibleForTesting static SearchEngine load(String identifier, InputStream stream) throws IOException, XmlPullParserException {
final SearchEngine searchEngine = new SearchEngine(identifier);
XmlPullParser parser = XmlPullParserFactory.newInstance().newPullParser();
parser.setInput(new InputStreamReader(stream, StandardCharsets.UTF_8));
parser.next();
readSearchPlugin(parser, searchEngine);
return searchEngine;
}
private static void readSearchPlugin(XmlPullParser parser, SearchEngine searchEngine) throws XmlPullParserException, IOException {
if (XmlPullParser.START_TAG != parser.getEventType()) {
throw new XmlPullParserException("Expected start tag: " + parser.getPositionDescription());
}
final String name = parser.getName();
if (!"SearchPlugin".equals(name) && !"OpenSearchDescription".equals(name)) {
throw new XmlPullParserException("Expected <SearchPlugin> or <OpenSearchDescription> as root tag: "
+ parser.getPositionDescription());
}
while (parser.next() != XmlPullParser.END_TAG) {
if (parser.getEventType() != XmlPullParser.START_TAG) {
continue;
}
final String tag = parser.getName();
if (tag.equals("ShortName")) {
readShortName(parser, searchEngine);
} else if (tag.equals("Url")) {
readUrl(parser, searchEngine);
} else if (tag.equals("Image")) {
readImage(parser, searchEngine);
} else {
skip(parser);
}
}
}
private static void readUrl(XmlPullParser parser, SearchEngine searchEngine) throws XmlPullParserException, IOException {
parser.require(XmlPullParser.START_TAG, null, "Url");
final String type = parser.getAttributeValue(null, "type");
final String template = parser.getAttributeValue(null, "template");
final String rel = parser.getAttributeValue(null, "rel");
Uri uri = Uri.parse(template);
while (parser.next() != XmlPullParser.END_TAG) {
if (parser.getEventType() != XmlPullParser.START_TAG) {
continue;
}
final String tag = parser.getName();
if (tag.equals("Param")) {
final String name = parser.getAttributeValue(null, "name");
final String value = parser.getAttributeValue(null, "value");
uri = uri.buildUpon().appendQueryParameter(name, value).build();
parser.nextTag();
} else {
skip(parser);
}
}
if (type.equals(URLTYPE_SEARCH_HTML)) {
// Prefer mobile URIs.
if (rel != null && rel.equals(URL_REL_MOBILE)) {
searchEngine.resultsUris.add(0, uri);
} else {
searchEngine.resultsUris.add(uri);
}
}
}
private static void skip(XmlPullParser parser) throws XmlPullParserException, IOException {
if (parser.getEventType() != XmlPullParser.START_TAG) {
throw new IllegalStateException();
}
int depth = 1;
while (depth != 0) {
switch (parser.next()) {
case XmlPullParser.END_TAG:
depth--;
break;
case XmlPullParser.START_TAG:
depth++;
break;
default:
// Do nothing - we're skipping content
}
}
}
private static void readShortName(XmlPullParser parser, SearchEngine searchEngine) throws IOException, XmlPullParserException {
parser.require(XmlPullParser.START_TAG, null, "ShortName");
if (parser.next() == XmlPullParser.TEXT) {
searchEngine.name = parser.getText();
parser.nextTag();
}
}
private static void readImage(XmlPullParser parser, SearchEngine searchEngine) throws IOException, XmlPullParserException {
parser.require(XmlPullParser.START_TAG, null, "Image");
if (parser.next() != XmlPullParser.TEXT) {
return;
}
final String uri = parser.getText();
if (!uri.startsWith(IMAGE_URI_PREFIX)) {
return;
}
final byte[] raw = Base64.decode(uri.substring(IMAGE_URI_PREFIX.length()), Base64.DEFAULT);
searchEngine.icon = BitmapFactory.decodeByteArray(raw, 0, raw.length);
parser.nextTag();
}
}