package dk.thoerup.androidutils;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.IOException;
import java.io.InputStream;
import java.io.RandomAccessFile;
import java.net.URL;
import java.net.URLConnection;

import android.app.AlertDialog;
import android.app.Notification;
import android.app.NotificationManager;
import android.app.PendingIntent;
import android.content.Context;
import android.content.DialogInterface;
import android.content.Intent;
import android.content.SharedPreferences;
import android.content.DialogInterface.OnClickListener;
import android.content.SharedPreferences.Editor;
import android.content.pm.PackageInfo;
import android.content.pm.PackageManager;
import android.content.pm.PackageManager.NameNotFoundException;
import android.net.Uri;
import android.os.AsyncTask;
import android.os.Environment;
import android.util.Log;

public class CheckUpdates {
	final static long TIMESPAN_DAY = 24*60*60*1000; // one day
 	
	final static String CHECKUPDATES = "CheckUpdates";
	final static String LASTCHECK = "lastcheck";
	
	int versionCode;
	String versionName;
	String packageName;
	String phone_model;
	String androidVersion;
	
	String title;
	
	
	Context context;

	public void checkForUpdates(Context context, String url, String title,  String apkUrl) {
		checkForUpdates(context, url, title,  apkUrl, false);
	}

	public void checkForUpdates(Context context, String url, String title,  String apkUrl, boolean forced) {
		this.context = context;
		this.title = title;
		
		SharedPreferences prefs = context.getSharedPreferences(CHECKUPDATES, Context.MODE_PRIVATE);
			
		long lastCheck = prefs.getLong(LASTCHECK, 0);		

		long now = System.currentTimeMillis(); //should i use  android.os.SystemClock.elapsedRealtime() instead ?
		Log.i(CHECKUPDATES, "Now=" + now + ",  lastCheck=" + lastCheck + ", lastCheck+timespan=" + (lastCheck + TIMESPAN_DAY) );
		
		if ( now > (lastCheck+TIMESPAN_DAY) ){

			PackageManager pm = context.getPackageManager();
			try {
				PackageInfo pi;

				pi = pm.getPackageInfo(context.getPackageName(), 0);

				versionCode = pi.versionCode;
				versionName = pi.versionName;
				packageName = pi.packageName;
				phone_model = android.os.Build.MODEL;
				androidVersion = android.os.Build.VERSION.RELEASE;
				
	
				UpdateTask task = new UpdateTask(forced);
				task.execute(url, apkUrl);
				

			} catch (NameNotFoundException e) {
				Log.e(CHECKUPDATES, "NamingException", e);
			}

		}
	}
	
	
	class UpdateTask extends AsyncTask<String,Void,Void> {
		boolean result = false;
		int newestVersion = 0;
		
		String apkUrl;
		
		boolean forced = false;
		
		public UpdateTask(boolean forced) {
			this.forced = forced;
		}

		@Override
		protected Void doInBackground(String... arg0) {			
			String requestUrl = arg0[0] + "?version=" + encode(versionName) + "&phone=" + encode(phone_model) + "&android=" + encode(androidVersion);
			apkUrl = arg0[1];
			
			try {
				URL url = new URL(requestUrl);
				URLConnection conn = url.openConnection();
				conn.setConnectTimeout(2500);
								
				String resultStr = readIOStream( conn.getInputStream() );
				resultStr = resultStr.trim();
				newestVersion = Integer.parseInt(resultStr);
				
				result = true;
				
			} catch (Exception e) {
				Log.e(CHECKUPDATES, "Check for " + packageName + " failed!", e);
			}
						
			return null;
		}
		
		private String encode(String data) {
			try {
				return java.net.URLEncoder.encode(data, "UTF-8");
			} catch (Exception e) {
				return data; //if encoding fails, return original and hope all goes well
			}
		}
		
		private String readIOStream(InputStream in) throws IOException {
			ByteArrayOutputStream baos = new ByteArrayOutputStream();
			
			byte buf[] = new byte[1024];
			int len;
			
			while ( (len=in.read(buf)) != -1) {
				baos.write(buf, 0, len);
			}
			
			return baos.toString(); 
		}

		@Override
		protected void onPostExecute(Void r) {
			super.onPostExecute(r);
			
			Log.i(CHECKUPDATES, "result=" + result + ", newestVersion" + newestVersion + ", versionCode=" + versionCode);
			
			if (result == true) {
				
				long now = System.currentTimeMillis();
				SharedPreferences prefs = context.getSharedPreferences(CHECKUPDATES, Context.MODE_PRIVATE);
				//when done write 
				
				Editor edit = prefs.edit();
				edit.putLong(LASTCHECK, now );
				edit.commit();
				
				
				if (newestVersion > versionCode) {			
					String launchUrl = (apkUrl == null) ? "market://search?q=pname:" + packageName : apkUrl;
					
					if (forced == true) { 
						forcedUpdate(launchUrl);
					} else {
						//showUpdateDialog(launchUrl);
						showNotification(launchUrl);
					}
				}
				
			}
			
		}
		
		private void forcedUpdate(String apkUrl) {
			Log.e(CHECKUPDATES, "Forced update started");
			try {
				byte[] apkData = HttpUtil.getContent(apkUrl, 5000);
				File tempFile = new File( Environment.getExternalStorageDirectory() + "/"  + HttpUtil.getLastPart(apkUrl) );
				
				if (tempFile.exists()) {
					tempFile.delete();
				}
				
				RandomAccessFile raf = new RandomAccessFile(tempFile,"rw");
				raf.write(apkData);
				
				Log.e(CHECKUPDATES, "File:" + tempFile.getPath());
				
				
				
				Intent i =new Intent();
				i.setAction(Intent.ACTION_VIEW);
				i.setDataAndType( Uri.fromFile(tempFile), "application/vnd.android.package-archive");
				i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK );


				try {
					context.startActivity(i);
				} catch (Exception e) {
					Log.e(CHECKUPDATES, "Activity launch failed", e); 
				}
				context = null;
				 
			} catch (Exception e) {
				Log.e(CHECKUPDATES, "forcedUpdate failed", e);
			}
		}
		
		private void showNotification(String launchUrl) {
			NotificationManager nm = (NotificationManager) context.getSystemService(Context.NOTIFICATION_SERVICE);
			//int icon = android.R.drawable.sym_action_email; //TODO: find a better icon
			int icon = R.drawable.searchicon;
			
			
			Notification notification = new Notification(icon, "Update available", System.currentTimeMillis() );
			notification.flags |= Notification.FLAG_AUTO_CANCEL ;
			
			CharSequence contentTitle = title;
			CharSequence contentText = "New version available.";
			Intent notificationIntent = new Intent(Intent.ACTION_VIEW, Uri.parse(launchUrl) );
			notificationIntent.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK );
			PendingIntent contentIntent = PendingIntent.getActivity(context, 0, notificationIntent, 0);

			notification.setLatestEventInfo(context, contentTitle, contentText, contentIntent);
			
			nm.notify(1, notification);
			
		}

		private void showUpdateDialog(final String launchUrl) {
			AlertDialog.Builder builder = new AlertDialog.Builder(context);
			builder.setTitle(title);
			builder.setMessage("This application has an a newer version available. Update now?");
			
			builder.setPositiveButton("Yes", new OnClickListener() {						
				public void onClick(DialogInterface dialog, int which) {

					
					Intent i = new Intent(Intent.ACTION_VIEW, Uri.parse(launchUrl) );
					i.setFlags(Intent.FLAG_ACTIVITY_NEW_TASK );
					try {
						context.startActivity(i);
					} catch (Exception e) {
						Log.e(CHECKUPDATES, "Activity launch failed", e);
					}
					context = null;
					
				}
			});
			builder.setNegativeButton("No", new OnClickListener() {
				public void onClick(DialogInterface dialog, int which) {
					context = null;
				}
			});
			
			try {
				builder.show();
			} catch (Exception e) {
				Log.e(CHECKUPDATES, "Builder.show failed", e);
			}
		}
		
	}
	
	
}