/*
 * Copyright 2013 MovingBlocks
 *
 * 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 org.terasology.version;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;

/**
 */
public final class TerasologyVersion {

    private static final Logger logger = LoggerFactory.getLogger(TerasologyVersion.class);

    private static TerasologyVersion instance;

    private static final String VERSION_INFO_FILE = "versionInfo.properties";

    private static final String BUILD_NUMBER = "buildNumber";
    private static final String BUILD_ID = "buildId";
    private static final String BUILD_TAG = "buildTag";
    private static final String BUILD_URL = "buildUrl";
    private static final String GIT_BRANCH = "gitBranch";
    private static final String GIT_COMMIT = "gitCommit";
    private static final String DATE_TIME = "dateTime";
    private static final String DISPLAY_VERSION = "displayVersion";
    private static final String ENGINE_VERSION = "engineVersion";

    private static final String DEFAULT_VALUE = "";

    private final String buildNumber;
    private final String buildId;
    private final String buildTag;
    private final String buildUrl;
    private final String gitBranch;
    private final String gitCommit;
    private final String dateTime;
    private final String toString;
    private final String displayVersion;
    private final String engineVersion;

    private TerasologyVersion() {
        final Properties properties = new Properties();
        try (InputStream inStream = this.getClass().getResourceAsStream(VERSION_INFO_FILE)) {
            if (inStream != null) {
                properties.load(inStream);
            }
        } catch (final IOException e) {
            logger.error("Loading {} failed", VERSION_INFO_FILE, e);
        }

        buildNumber = properties.getProperty(BUILD_NUMBER, DEFAULT_VALUE);
        buildId = properties.getProperty(BUILD_ID, DEFAULT_VALUE);
        buildTag = properties.getProperty(BUILD_TAG, DEFAULT_VALUE);
        buildUrl = properties.getProperty(BUILD_URL, DEFAULT_VALUE);
        gitBranch = properties.getProperty(GIT_BRANCH, DEFAULT_VALUE);
        gitCommit = properties.getProperty(GIT_COMMIT, DEFAULT_VALUE);
        dateTime = properties.getProperty(DATE_TIME, DEFAULT_VALUE);
        displayVersion = properties.getProperty(DISPLAY_VERSION, DEFAULT_VALUE);
        engineVersion = properties.getProperty(ENGINE_VERSION, DEFAULT_VALUE);

        final StringBuilder toStringBuilder = new StringBuilder();
        toStringBuilder.append("[");
        toStringBuilder.append(BUILD_NUMBER);
        toStringBuilder.append("=");
        toStringBuilder.append(buildNumber);
        toStringBuilder.append(", ");
        toStringBuilder.append(BUILD_ID);
        toStringBuilder.append("=");
        toStringBuilder.append(buildId);
        toStringBuilder.append(", ");
        toStringBuilder.append(BUILD_TAG);
        toStringBuilder.append("=");
        toStringBuilder.append(buildTag);
        toStringBuilder.append(", ");
        toStringBuilder.append(BUILD_URL);
        toStringBuilder.append("=");
        toStringBuilder.append(buildUrl);
        toStringBuilder.append(", ");
        toStringBuilder.append(GIT_BRANCH);
        toStringBuilder.append("=");
        toStringBuilder.append(gitBranch);
        toStringBuilder.append(", ");
        toStringBuilder.append(GIT_COMMIT);
        toStringBuilder.append("=");
        toStringBuilder.append(gitCommit);
        toStringBuilder.append(", ");
        toStringBuilder.append(DATE_TIME);
        toStringBuilder.append("=");
        toStringBuilder.append(dateTime);
        toStringBuilder.append(", ");
        toStringBuilder.append(DISPLAY_VERSION);
        toStringBuilder.append("=");
        toStringBuilder.append(displayVersion);
        toStringBuilder.append(", ");
        toStringBuilder.append(ENGINE_VERSION);
        toStringBuilder.append("=");
        toStringBuilder.append(engineVersion);
        toStringBuilder.append("]");
        toString = toStringBuilder.toString();
    }

    public static TerasologyVersion getInstance() {
        if (instance == null) {
            instance = new TerasologyVersion();
        }
        return instance;
    }

    public String getBuildNumber() {
        return buildNumber;
    }

    public String getBuildId() {
        return buildId;
    }

    public String getBuildTag() {
        return buildTag;
    }

    public String getBuildUrl() {
        return buildUrl;
    }

    public String getGitBranch() {
        return gitBranch;
    }

    public String getGitCommit() {
        return gitCommit;
    }

    public String getDateTime() {
        return dateTime;
    }

    public String getDisplayVersion() {
        return displayVersion;
    }

    public String getengineVersion() {
        return engineVersion;
    }

    /**
     * Makes a pretty version string for displaying to human users
     * @return prettified version String
     */
    public String getHumanVersion() {
        // TODO replace with a nicer version later with full version numbering in place
        String humanVersion = "";
        TerasologyVersion ver = getInstance();

        // MOAR CAPS!
        if (!ver.getDisplayVersion().trim().equals("")) {
            humanVersion = displayVersion.toUpperCase();
        }

        // Expect tag to start with "jenkins-" and remove that
        if (ver.getBuildTag().trim().length() > 8) {
            humanVersion += " " + ver.getBuildTag().substring(8);
        }

        // Expect a date string but ignore time of day
        if (ver.getDateTime().trim().length() > 10) {
            humanVersion += " " + ver.getDateTime().substring(0, 10);
        }

        return humanVersion;
    }

    @Override
    public String toString() {
        return toString;
    }

}