package de.thedevstack.conversationsplus;

import android.Manifest;
import android.app.Application;
import android.content.Context;
import android.content.pm.PackageManager;
import android.os.Build;
import android.os.PowerManager;
import android.preference.PreferenceManager;

import java.io.File;
import java.security.SecureRandom;

import de.duenndns.ssl.MemorizingTrustManager;
import de.thedevstack.conversationsplus.http.HttpClient;
import de.thedevstack.conversationsplus.persistance.FileBackend;
import de.thedevstack.conversationsplus.services.filetransfer.FileTransferManager;
import de.thedevstack.conversationsplus.services.filetransfer.http.download.HttpDownloadFileTransferService;
import de.thedevstack.conversationsplus.services.filetransfer.http.upload.HttpUploadFileTransferService;
import de.thedevstack.conversationsplus.services.filetransfer.jingle.JingleFileTransferService;
import de.thedevstack.conversationsplus.utils.ImageUtil;
import de.thedevstack.conversationsplus.utils.SerialSingleThreadExecutor;

/**
 * This class is used to provide static access to the applicationcontext.
 */
public class ConversationsPlusApplication extends Application {
    /**
     * Application instance for static access
     */
    private static ConversationsPlusApplication instance;

    private final SerialSingleThreadExecutor mFileAddingExecutor = new SerialSingleThreadExecutor();
    private final SerialSingleThreadExecutor mDatabaseExecutor = new SerialSingleThreadExecutor();

    private MemorizingTrustManager memorizingTrustManager;
    private SecureRandom secureRandom;

    /**
     * Initializes the application and saves its instance.
     */
    public void onCreate(){
        super.onCreate();
        ConversationsPlusApplication.instance = this;
        ConversationsPlusPreferences.init(PreferenceManager.getDefaultSharedPreferences(getAppContext()));
        this.initializeSecurity();
        ImageUtil.initBitmapCache();
        FileBackend.init();
        FileTransferManager.init(new HttpUploadFileTransferService(), new JingleFileTransferService(), new HttpDownloadFileTransferService());
        HttpClient.init();
    }

    /**
     * Initializes security features.
     */
    private void initializeSecurity() {
        this.secureRandom = new SecureRandom();
        ConversationsPlusApplication.updateMemorizingTrustmanager();
    }

    /**
     * Returns the instance of the application
     * @return this application instance
     */
    public static ConversationsPlusApplication getInstance() {
        return ConversationsPlusApplication.instance;
    }

    public static void executeFileAdding(Runnable r) {
        getInstance().mFileAddingExecutor.execute(r);
    }

    public static void executeDatabaseOperation(Runnable r) {
        getInstance().mDatabaseExecutor.execute(r);
    }

    /**
     * Returns the application's context.
     * @return Context the application's context
     */
    public static Context getAppContext() {
        return ConversationsPlusApplication.instance.getApplicationContext();
    }

    /**
     * Returns the application's private data directory.
     * @return File the application's private data dir
     */
    public static File getPrivateFilesDir() {
        return ConversationsPlusApplication.instance.getFilesDir();
    }

    /**
     * Returns the version of the application.
     * @see android.content.pm.PackageInfo#versionName
     * @return a string representation of the version stored in packageInfo
     */
    public static String getVersion() {
        final String packageName = ConversationsPlusApplication.getAppContext().getPackageName();
        if (packageName != null) {
            try {
                return ConversationsPlusApplication.getAppContext().getPackageManager().getPackageInfo(packageName, 0).versionName;
            } catch (final PackageManager.NameNotFoundException e) {
                return "unknown";
            }
        } else {
            return "unknown";
        }
    }

    /**
     * Returns the application's name.
     * @return the name as it is defined in R.string.app_name
     */
    public static String getName() {
        return ConversationsPlusApplication.getAppContext().getString(R.string.app_name);
    }

    /**
     * Returns the name and the version of this application.
     * @see #getName() and #getVersion
     * @return a concatination of name and version with a whitespace in between
     */
    public static String getNameAndVersion() {
        return getName() + " " + getVersion();
    }

    public static PowerManager.WakeLock createPartialWakeLock(String name) {
        PowerManager powerManager = (PowerManager) getAppContext().getSystemService(Context.POWER_SERVICE);
        return powerManager.newWakeLock(PowerManager.PARTIAL_WAKE_LOCK, name);
    }

    public static boolean hasStoragePermission() {
        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.M) {
            return ConversationsPlusApplication.getAppContext().checkSelfPermission(Manifest.permission.WRITE_EXTERNAL_STORAGE) == PackageManager.PERMISSION_GRANTED;
        } else {
            return true;
        }
    }

    public static MemorizingTrustManager getMemorizingTrustManager() {
        return getInstance().memorizingTrustManager;
    }

    public void setMemorizingTrustManager(MemorizingTrustManager trustManager) {
        this.memorizingTrustManager = trustManager;
    }

    public static void updateMemorizingTrustmanager() {
        final MemorizingTrustManager tm;
        if (ConversationsPlusPreferences.dontTrustSystemCAs()) {
            tm = new MemorizingTrustManager(getAppContext(), null);
        } else {
            tm = new MemorizingTrustManager(getAppContext());
        }
        getInstance().setMemorizingTrustManager(tm);
    }

    public static SecureRandom getSecureRandom() {
        return getInstance().secureRandom;
    }
}