Utils.java

/*
 * Copyright (C) 2009 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.android.settings.fuelgauge;

import android.content.Context;

import com.android.settings.R;

/**
 * Contains utility functions for formatting elapsed time and consumed bytes
 */
public class Utils {
    private static final int SECONDS_PER_MINUTE = 60;
    private static final int SECONDS_PER_HOUR = 60 * 60;
    private static final int SECONDS_PER_DAY = 24 * 60 * 60;

    /**
     * Returns elapsed time for the given millis, in the following format:
     * 2d 5h 40m 29s
     * @param context the application context
     * @param millis the elapsed time in milli seconds
     * @return the formatted elapsed time
     */
    public static String formatElapsedTime(Context context, double millis) {
        StringBuilder sb = new StringBuilder();
        int seconds = (int) Math.floor(millis / 1000);

        int days = 0, hours = 0, minutes = 0;
        if (seconds > SECONDS_PER_DAY) {
            days = seconds / SECONDS_PER_DAY;
            seconds -= days * SECONDS_PER_DAY;
        }
        if (seconds > SECONDS_PER_HOUR) {
            hours = seconds / SECONDS_PER_HOUR;
            seconds -= hours * SECONDS_PER_HOUR;
        }
        if (seconds > SECONDS_PER_MINUTE) {
            minutes = seconds / SECONDS_PER_MINUTE;
            seconds -= minutes * SECONDS_PER_MINUTE;
        }
        if (days > 0) {
            sb.append(context.getString(R.string.battery_history_days,
                    days, hours, minutes, seconds));
        } else if (hours > 0) {
            sb.append(context.getString(R.string.battery_history_hours, hours, minutes, seconds));
        } else if (minutes > 0) {
            sb.append(context.getString(R.string.battery_history_minutes, minutes, seconds));
        } else {
            sb.append(context.getString(R.string.battery_history_seconds, seconds));
        }
        return sb.toString();
    }

    /**
     * Formats data size in KB, MB, from the given bytes.
     * @param context the application context
     * @param bytes data size in bytes
     * @return the formatted size such as 4.52 MB or 245 KB or 332 bytes
     */
    public static String formatBytes(Context context, double bytes) {
        // TODO: I18N
        if (bytes > 1000 * 1000) {
            return String.format("%.2f MB", ((int) (bytes / 1000)) / 1000f);
        } else if (bytes > 1024) {
            return String.format("%.2f KB", ((int) (bytes / 10)) / 100f);
        } else {
            return String.format("%d bytes", (int) bytes);
        }
    }
}