1 files changed, 124 insertions, 0 deletions
diff --git a/partner_support/src/com/google/android/tv/partner/support/TunerSetupUtils.java b/partner_support/src/com/google/android/tv/partner/support/TunerSetupUtils.java
new file mode 100644
index 00000000..e25d5836
--- /dev/null
+++ b/partner_support/src/com/google/android/tv/partner/support/TunerSetupUtils.java
@@ -0,0 +1,124 @@
+/*
+ * Copyright (C) 2017 The Android Open Source Project
+ *
+ * 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.android.tv.partner.support;
+
+import android.support.annotation.VisibleForTesting;
+import android.text.TextUtils;
+import android.util.Log;
+import android.util.Pair;
+import java.util.ArrayList;
+import java.util.Arrays;
+import java.util.Collections;
+import java.util.Comparator;
+import java.util.List;
+import java.util.regex.Pattern;
+
+/** Utility class for providing tuner setup. */
+public class TunerSetupUtils {
+    private static final String TAG = "TunerSetupUtils";
+
+    private static final Pattern CHANNEL_NUMBER_DELIMITER = Pattern.compile("([ .-])");
+
+    public static List<Pair<Lineup, Integer>> lineupChannelMatchCount(
+            List<Lineup> lineups, List<String> localChannels) {
+        List<Pair<Lineup, Integer>> result = new ArrayList<>();
+        List<List<String>> parsedLocalChannels = parseChannelNumbers(localChannels);
+        for (Lineup lineup : lineups) {
+            result.add(
+                    new Pair<>(lineup, getMatchCount(lineup.getChannels(), parsedLocalChannels)));
+        }
+        // sort in decreasing order
+        Collections.sort(
+                result,
+                new Comparator<Pair<Lineup, Integer>>() {
+                    @Override
+                    public int compare(Pair<Lineup, Integer> pair, Pair<Lineup, Integer> other) {
+                        return Integer.compare(other.second, pair.second);
+                    }
+                });
+        return result;
+    }
+
+    @VisibleForTesting
+    static int getMatchCount(List<String> lineupChannels, List<List<String>> parsedLocalChannels) {
+        int count = 0;
+        List<List<String>> parsedLineupChannels = parseChannelNumbers(lineupChannels);
+        for (List<String> parsedLineupChannel : parsedLineupChannels) {
+            for (List<String> parsedLocalChannel : parsedLocalChannels) {
+                if (matchChannelNumber(parsedLineupChannel, parsedLocalChannel)) {
+                    count++;
+                    break;
+                }
+            }
+        }
+        return count;
+    }
+
+    /**
+     * Parses the channel number string to a list of numbers (major number, minor number, etc.).
+     *
+     * @param channelNumber the display number of the channel
+     * @return a list of numbers
+     */
+    @VisibleForTesting
+    static List<String> parseChannelNumber(String channelNumber) {
+        List<String> numbers =
+                new ArrayList<>(
+                        Arrays.asList(TextUtils.split(channelNumber, CHANNEL_NUMBER_DELIMITER)));
+        numbers.removeAll(Collections.singleton(""));
+        if (numbers.size() < 1 || numbers.size() > 2) {
+            Log.w(TAG, "unsupported channel number format: " + channelNumber);
+            return new ArrayList<>();
+        }
+        return numbers;
+    }
+
+    /**
+     * Parses a list of channel numbers. See {@link #parseChannelNumber(String)}.
+     *
+     * @param channelNumbers a list of channel display numbers
+     */
+    @VisibleForTesting
+    static List<List<String>> parseChannelNumbers(List<String> channelNumbers) {
+        List<List<String>> numbers = new ArrayList<>(channelNumbers.size());
+        for (String channelNumber : channelNumbers) {
+            if (!TextUtils.isEmpty(channelNumber)) {
+                numbers.add(parseChannelNumber(channelNumber));
+            }
+        }
+        return numbers;
+    }
+
+    /**
+     * Checks whether two lists of channel numbers match or not. If the sizes are different,
+     * additional elements are ignore.
+     */
+    @VisibleForTesting
+    static boolean matchChannelNumber(List<String> numbers, List<String> other) {
+        if (numbers.isEmpty() || other.isEmpty()) {
+            return false;
+        }
+        int i = 0;
+        int j = 0;
+        while (i < numbers.size() && j < other.size()) {
+            if (!numbers.get(i++).equals(other.get(j++))) {
+                return false;
+            }
+        }
+        return true;
+    }
+}