Uses the sync API v1 fro syncing.

For the syncing, the app no longer calls the weird-homemade-frankenstein-looking xml tha called before, but the sync API v1. As of now, it updates the versions of the different database sections, but it doesn't use them as reference (still uses the old preference value). Also, the actual sync data is received, but it still needs to be parsed and inserted into the database.

app/src/main/java/com/ivalentin/margolariak/GM.java

@@ -17,12 +17,29 @@ import java.util.Locale;
  *
  */
 final class GM {
-	
+
+	static final String CLIENT = "com.ivalentin.margolariak";
+
 	/**
 	 * Address where the web server is
 	 */
 	static final String SERVER = "http://margolariak.com";
 
+	static final String SERVER_SYNC = "/API/v1/sync.php";
+
+	static final String SERVER_SYNC_KEY_CLIENT = "client";
+	static final String SERVER_SYNC_KEY_USER = "user";
+	static final String SERVER_SYNC_KEY_ACTION = "action";
+	static final String SERVER_SYNC_KEY_SECTION = "section";
+	static final String SERVER_SYNC_KEY_VERSION = "version";
+	static final String SERVER_SYNC_KEY_FOREGROUND = "foreground";
+	static final String SERVER_SYNC_KEY_FORMAT = "format";
+	static final String SERVER_SYNC_KEY_LANG = "lang";
+
+	static final String SERVER_SYNC_VALUE_ACTION = "sync";
+	static final String SERVER_SYNC_VALUE_SECTION = "all";
+	static final String SERVER_SYNC_VALUE_FORMAT = "json";
+
 	/**
 	 * Code for the location permission request
 	 */

app/src/main/java/com/ivalentin/margolariak/MainActivity.java

@@ -597,6 +597,7 @@ public class MainActivity extends Activity{
 			db.execSQL("CREATE TABLE IF NOT EXISTS post_image (id INT, post INT, image VARCHAR, idx INT);");
 			db.execSQL("CREATE TABLE IF NOT EXISTS post_tag (post INT, tag VARCHAR);");
 			db.execSQL("CREATE TABLE IF NOT EXISTS settings (name VARCHAR, value VARCHAR);");
+			db.execSQL("CREATE TABLE IF NOT EXISTS version (section VARCHAR, version INT);");
 			db.close();
     	}
     	catch (Exception ex){

app/src/main/java/com/ivalentin/margolariak/Sync.java

@@ -1,5 +1,14 @@
 package com.ivalentin.margolariak;
 
+import java.io.BufferedInputStream;
+import java.io.BufferedReader;
+import java.io.IOException;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.net.HttpURLConnection;
+import java.net.MalformedURLException;
+import java.net.URL;
+import java.net.URLEncoder;
 import java.util.ArrayList;
 import java.util.List;
 
@@ -18,6 +27,8 @@ import android.widget.ImageView;
 import android.widget.ProgressBar;
 import android.widget.TextView;
 
+import org.json.*;
+
 /**
  * AsyncTask that synchronizes the online database to the device.
  * Is run every time the app is started, and periodically in the background.
@@ -171,7 +182,6 @@ class Sync extends AsyncTask<Void, Void, Void> {
 	/**
 	 * Called when the AsyncTask is updated.
 	 * Used to change text in the sync window.
-	 *
 	 */
 	protected void onProgressUpdate(Void...progress) {
 		if (doProgress){
@@ -183,15 +193,177 @@ class Sync extends AsyncTask<Void, Void, Void> {
 		}
 	}
 
+	/**
+	 * Creates the URL required to performa a sync. Uses static data and data passed as arguments.
+	 *
+	 * @param user A unique user identifier.
+	 * @param version The db version of the client.
+	 * @param foreground 1 if the sync is done while the app is running, 0 otherwise.
+	 * @param lang Two letter language identifier.
+	 * @return The URL that will be used for syncing.
+	 */
+	private String buildUrl(String user, int version, int foreground, String lang){
+		String url = "";
+		try {
+			url = GM.SERVER + GM.SERVER_SYNC + "?" +
+					GM.SERVER_SYNC_KEY_CLIENT + "=" + URLEncoder.encode(GM.CLIENT, "UTF-8") + "&" +
+					GM.SERVER_SYNC_KEY_USER + "=" + URLEncoder.encode(user, "UTF-8") + "&" +
+					GM.SERVER_SYNC_KEY_ACTION + "=" + URLEncoder.encode(GM.SERVER_SYNC_VALUE_ACTION, "UTF-8") + "&" +
+					GM.SERVER_SYNC_KEY_SECTION + "=" + URLEncoder.encode(GM.SERVER_SYNC_VALUE_SECTION, "UTF-8") + "&" +
+					GM.SERVER_SYNC_KEY_VERSION + "=" + version + "&" +
+					GM.SERVER_SYNC_KEY_FOREGROUND + "=" + foreground + "&" +
+					GM.SERVER_SYNC_KEY_FORMAT + "=" + URLEncoder.encode(GM.SERVER_SYNC_VALUE_FORMAT, "UTF-8") + "&" +
+					GM.SERVER_SYNC_KEY_LANG + "=" + URLEncoder.encode(lang, "UTF-8");
+		}
+		catch (java.io.UnsupportedEncodingException ex){
+			Log.e("UTF-8", "Error encoding url for sync \"" + url + "\" - " + ex.toString());
+		}
+		return url;
+	}
+
+	/**
+	 * Stores version data for each section in the database.
+	 * Uses a custom JSON parser.
+	 *
+	 * @param db Database store the data.
+	 * @param versions List of strings with data about the versions.
+	 * @return False if there were errors, true otherwise.
+	 */
+	protected boolean saveVersions(SQLiteDatabase db, String versions){
+		String str = versions;
+		String key;
+		boolean error = false;
+		int value;
+		int totalVersions = 0;
+		int[] values = new int[99];
+		String[] keys = new String[99];
+		try {
+			while (str.indexOf("{") > 0){
+				key = str.substring(str.indexOf("{\"") + 2, str.indexOf("\":"));
+				str = str.substring(str.indexOf("\":\"") + 3);
+				value = Integer.parseInt(str.substring(0, str.indexOf("\"")));
+				str = str.substring(str.indexOf("}") + 1);
+				keys[totalVersions] = key;
+				values[totalVersions] = value;
+				totalVersions ++;
+			}
+			if (totalVersions > 0){
+				db.execSQL("CREATE TABLE IF NOT EXISTS version (section VARCHAR, version INT);");
+				db.execSQL("DELETE FROM version;");
+				for (int i = 0; i < totalVersions; i ++){
+					db.execSQL("INSERT INTO version VALUES ('" + keys[i] + "', " + values[i] + ");");
+				}
+			}
+
+		}
+		catch (Exception ex){
+			error = true;
+			Log.e("saveVersions", "Error saving the remote db versions: " + ex.toString());
+		}
+
+		return error;
+	}
+
+	/**
+	 * Stores version data for each section in the database.
+	 * Uses a custom JSON parser.
+	 *
+	 * @param db Database store the data.
+	 * @param data List of strings in json format with the tables.
+	 * @return False if there were errors, true otherwise.
+	 */
+	protected boolean saveData(SQLiteDatabase db, String data){
+
+		return true;
+	}
+
+
 	/**
 	 * The sweet stuff. Actually performs the sync. 
-	 * 
-	 * //@see android.os.AsyncTask#doInBackground(Params[])
 	 */
 	@Override
 	protected Void doInBackground(Void... params) {
 
-		//Open the database. f its locked, exit.
+		//Get preferences
+		SharedPreferences preferences = myContextRef.getSharedPreferences(GM.PREF, Context.MODE_PRIVATE);
+		SharedPreferences.Editor prefEditor;
+		prefEditor = preferences.edit();
+
+		//Get usefull data for the uri
+		String userCode = preferences.getString(GM.USER_CODE, "");
+		int dbVersion = preferences.getInt(GM.PREF_DB_VERSION, GM.DEFAULT_PREF_DB_VERSION);
+
+		//Get database. Stop if it's locked
+		SQLiteDatabase db = myContextRef.openOrCreateDatabase(GM.DB_NAME, Activity.MODE_PRIVATE, null);
+		if (db.isReadOnly()){
+			Log.e("Db ro", "Database is locked and in read only mode. Skipping sync.");
+			return null;
+		}
+
+		URL url;
+		String uri = buildUrl(userCode, dbVersion, fg, GM.getLang());
+		try {
+			url = new URL(uri);
+
+			HttpURLConnection urlConnection = (HttpURLConnection) url.openConnection();
+
+			int httpCode = urlConnection.getResponseCode();
+			switch (httpCode){
+				case 400:	//Client error: Bad request
+					Log.e("Sync error", "The server returned a 400 code (Client Error: Bad request) for the url \"" + uri + "\"");
+					break;
+				case 403:	//Client error: Forbidden
+					Log.e("Sync error", "The server returned a 403 code (Client Error: Forbidden) for the url \"" + uri + "\"");
+					break;
+				case 204:	//Success: No content
+					Log.d("Sync success", "The server returned a 204 code (Success: No content) for the url \"" + uri + "\". Stoping sync process...");
+					break;
+				case 200:	//Success: OK
+					Log.d("Sync", "The server returned a 200 code (Success: OK) for the url \"" + uri + "\". Now syncing...");
+					InputStream in = new BufferedInputStream(urlConnection.getInputStream());
+					BufferedReader br = new BufferedReader(new InputStreamReader(urlConnection.getInputStream()));
+					StringBuilder sb = new StringBuilder();
+					String o;
+					while ((o = br.readLine()) != null)
+						sb.append(o);
+
+					//Get the string with the sync json. (The whole page)
+					String strSync = sb.toString();
+
+					//Get the JSON object from the string.
+					JSONObject jsonSync = new JSONObject(strSync);
+					jsonSync = new JSONObject(jsonSync.get("sync").toString().substring(1, jsonSync.get("sync").toString().length() - 1));
+
+					//Get the string wit the versions in JSON format.
+					String strVersion = jsonSync.get("version").toString();
+
+					//Get the string with the data in JSON format,
+					saveVersions(db, strVersion);
+					//saveData(db, data);
+
+					break;
+				default:
+					Log.e("Sync error", "The server returned an unexpected code (" + httpCode + ") for the url \"" + uri + "\"");
+			}
+			urlConnection.disconnect();
+			return null;
+
+		}
+		catch (MalformedURLException e) {
+			Log.e("Sync error", "Malformed URL (" + uri + "): " + e.toString());
+			e.printStackTrace();
+		}
+		catch (IOException e) {
+			Log.e("Sync error", "IOException for URL (" + uri + "): " + e.toString());
+			e.printStackTrace();
+		}
+		catch (org.json.JSONException e) {
+			Log.e("Sync error", "JSONException for URL (" + uri + "): " + e.toString());
+			e.printStackTrace();
+		}
+
+
+		/*//Open the database. f its locked, exit.
 		SQLiteDatabase db = myContextRef.openOrCreateDatabase(GM.DB_NAME, Activity.MODE_PRIVATE, null);
 		if (db.isReadOnly()){
 			Log.e("Db ro", "Database is locked and in read only mode. Skipping sync.");
@@ -379,7 +551,7 @@ class Sync extends AsyncTask<Void, Void, Void> {
 		}
 		catch(Exception ex){
 			Log.e("Sync error", "Error updating info: " + ex.toString());
-		}
+		}*/
 		return null;
     	
 	}