app/src/main/java/net/ktnx/mobileledger/async/RetrieveTransactionsTask.java

   1 /*
   2  * Copyright © 2018 Damyan Ivanov.
   3  * This file is part of Mobile-Ledger.
   4  * Mobile-Ledger is free software: you can distribute it and/or modify it
   5  * under the term of the GNU General Public License as published by
   6  * the Free Software Foundation, either version 3 of the License, or
   7  * (at your opinion), any later version.
   8  *
   9  * Mobile-Ledger is distributed in the hope that it will be useful,
  10  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  11  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
  12  * GNU General Public License terms for details.
  13  *
  14  * You should have received a copy of the GNU General Public License
  15  * along with Mobile-Ledger. If not, see <https://www.gnu.org/licenses/>.
  16  */
  17
  18 package net.ktnx.mobileledger.async;
  19
  20 import android.annotation.SuppressLint;
  21 import android.content.Context;
  22 import android.content.SharedPreferences;
  23 import android.database.sqlite.SQLiteDatabase;
  24 import android.os.AsyncTask;
  25 import android.util.Log;
  26
  27 import net.ktnx.mobileledger.R;
  28 import net.ktnx.mobileledger.TransactionListActivity;
  29 import net.ktnx.mobileledger.model.LedgerTransaction;
  30 import net.ktnx.mobileledger.model.LedgerTransactionItem;
  31 import net.ktnx.mobileledger.utils.MobileLedgerDatabase;
  32 import net.ktnx.mobileledger.utils.NetworkUtil;
  33
  34 import java.io.BufferedReader;
  35 import java.io.FileNotFoundException;
  36 import java.io.IOException;
  37 import java.io.InputStream;
  38 import java.io.InputStreamReader;
  39 import java.lang.ref.WeakReference;
  40 import java.net.HttpURLConnection;
  41 import java.net.MalformedURLException;
  42 import java.util.regex.Matcher;
  43 import java.util.regex.Pattern;
  44
  45
  46 public class RetrieveTransactionsTask extends
  47         AsyncTask<RetrieveTransactionsTask.Params, RetrieveTransactionsTask.Progress, Void> {
  48     private static final Pattern transactionStartPattern = Pattern.compile("<tr class=\"title\" " +
  49                                                                            "id=\"transaction-(\\d+)\"><td class=\"date\"[^\\\"]*>([\\d.-]+)</td>");
  50     private static final Pattern transactionDescriptionPattern =
  51             Pattern.compile("<tr class=\"posting\" title=\"(\\S+)\\s(.+)");
  52     private static final Pattern transactionDetailsPattern =
  53             Pattern.compile("^\\s+" + "(\\S[\\S\\s]+\\S)\\s\\s+([-+]?\\d[\\d,.]*)");
  54     private static final Pattern endPattern = Pattern.compile("\\bid=\"addmodal\"");
  55     protected WeakReference<TransactionListActivity> contextRef;
  56     protected int error;
  57     private boolean success;
  58     public RetrieveTransactionsTask(WeakReference<TransactionListActivity> contextRef) {
  59         this.contextRef = contextRef;
  60     }
  61     private static final void L(String msg) {
  62         Log.d("transaction-parser", msg);
  63     }
  64     @Override
  65     protected void onProgressUpdate(Progress... values) {
  66         super.onProgressUpdate(values);
  67         TransactionListActivity context = getContext();
  68         if (context == null) return;
  69         context.onRetrieveProgress(values[0]);
  70     }
  71     @Override
  72     protected void onPreExecute() {
  73         super.onPreExecute();
  74         TransactionListActivity context = getContext();
  75         if (context == null) return;
  76         context.onRetrieveStart();
  77     }
  78     @Override
  79     protected void onPostExecute(Void aVoid) {
  80         super.onPostExecute(aVoid);
  81         TransactionListActivity context = getContext();
  82         if (context == null) return;
  83         context.onRetrieveDone(success);
  84     }
  85     @SuppressLint("DefaultLocale")
  86     @Override
  87     protected Void doInBackground(Params... params) {
  88         Progress progress = new Progress();
  89         success = false;
  90         try {
  91             HttpURLConnection http =
  92                     NetworkUtil.prepare_connection(params[0].getBackendPref(), "journal");
  93             http.setAllowUserInteraction(false);
  94             publishProgress(progress);
  95             Context ctx = contextRef.get();
  96             if (ctx == null) return null;
  97             try (MobileLedgerDatabase dbh = new MobileLedgerDatabase(ctx)) {
  98                 try (SQLiteDatabase db = dbh.getWritableDatabase()) {
  99                     try (InputStream resp = http.getInputStream()) {
 100                         if (http.getResponseCode() != 200) throw new IOException(
 101                                 String.format("HTTP error %d", http.getResponseCode()));
 102                         db.beginTransaction();
 103                         try {
 104                             db.execSQL("DELETE FROM transactions;");
 105                             db.execSQL("DELETE FROM transaction_accounts");
 106
 107                             int state = ParserState.EXPECTING_JOURNAL;
 108                             String line;
 109                             BufferedReader buf =
 110                                     new BufferedReader(new InputStreamReader(resp, "UTF-8"));
 111
 112                             int transactionCount = 0;
 113                             int transactionId = 0;
 114                             LedgerTransaction transaction = null;
 115                             LINES:
 116                             while ((line = buf.readLine()) != null) {
 117                                 Matcher m;
 118                                 L(String.format("State is %d", state));
 119                                 switch (state) {
 120                                     case ParserState.EXPECTING_JOURNAL:
 121                                         if (line.equals("<h2>General Journal</h2>")) {
 122                                             state = ParserState.EXPECTING_TRANSACTION;
 123                                             L("→ expecting transaction");
 124                                         }
 125                                         break;
 126                                     case ParserState.EXPECTING_TRANSACTION:
 127                                         m = transactionStartPattern.matcher(line);
 128                                         if (m.find()) {
 129                                             transactionId = Integer.valueOf(m.group(1));
 130                                             state = ParserState.EXPECTING_TRANSACTION_DESCRIPTION;
 131                                             L(String.format("found transaction %d → expecting " +
 132                                                             "description", transactionId));
 133                                             progress.setProgress(++transactionCount);
 134                                             if (progress.getTotal() == Progress.INDETERMINATE)
 135                                                 progress.setTotal(transactionId);
 136                                             publishProgress(progress);
 137                                         }
 138                                         m = endPattern.matcher(line);
 139                                         if (m.find()) {
 140                                             L("--- transaction list complete ---");
 141                                             success = true;
 142                                             break LINES;
 143                                         }
 144                                         break;
 145                                     case ParserState.EXPECTING_TRANSACTION_DESCRIPTION:
 146                                         m = transactionDescriptionPattern.matcher(line);
 147                                         if (m.find()) {
 148                                             if (transactionId == 0)
 149                                                 throw new TransactionParserException(
 150                                                         "Transaction Id is 0 while expecting " +
 151                                                         "description");
 152
 153                                             transaction =
 154                                                     new LedgerTransaction(transactionId, m.group(1),
 155                                                             m.group(2));
 156                                             state = ParserState.EXPECTING_TRANSACTION_DETAILS;
 157                                             L(String.format("transaction %d created for %s (%s) →" +
 158                                                             " expecting details", transactionId,
 159                                                     m.group(1), m.group(2)));
 160                                         }
 161                                         break;
 162                                     case ParserState.EXPECTING_TRANSACTION_DETAILS:
 163                                         if (line.isEmpty()) {
 164                                             // transaction data collected
 165                                             transaction.insertInto(db);
 166
 167                                             state = ParserState.EXPECTING_TRANSACTION;
 168                                             L(String.format("transaction %s saved → expecting " +
 169                                                             "transaction", transaction.getId()));
 170                                         }
 171                                         else {
 172                                             m = transactionDetailsPattern.matcher(line);
 173                                             if (m.find()) {
 174                                                 String acc_name = m.group(1);
 175                                                 String amount = m.group(2);
 176                                                 amount = amount.replace(',', '.');
 177                                                 transaction.add_item(
 178                                                         new LedgerTransactionItem(acc_name,
 179                                                                 Float.valueOf(amount)));
 180                                                 L(String.format("%s = %s", acc_name, amount));
 181                                             }
 182                                             else throw new IllegalStateException(String.format(
 183                                                     "Can't parse transaction details"));
 184                                         }
 185                                         break;
 186                                     default:
 187                                         throw new RuntimeException(
 188                                                 String.format("Unknown " + "parser state %d",
 189                                                         state));
 190                                 }
 191                             }
 192                             db.setTransactionSuccessful();
 193                         }
 194                         finally {
 195                             db.endTransaction();
 196                         }
 197                     }
 198                 }
 199             }
 200         }
 201         catch (MalformedURLException e) {
 202             error = R.string.err_bad_backend_url;
 203             e.printStackTrace();
 204         }
 205         catch (FileNotFoundException e) {
 206             error = R.string.err_bad_auth;
 207             e.printStackTrace();
 208         }
 209         catch (IOException e) {
 210             error = R.string.err_net_io_error;
 211             e.printStackTrace();
 212         }
 213         return null;
 214     }
 215     TransactionListActivity getContext() {
 216         return contextRef.get();
 217     }
 218
 219     public static class Params {
 220         static final int DEFAULT_LIMIT = 100;
 221         private SharedPreferences backendPref;
 222         private String accountsRoot;
 223         private int limit;
 224
 225         public Params(SharedPreferences backendPref) {
 226             this.backendPref = backendPref;
 227             this.accountsRoot = null;
 228             this.limit = DEFAULT_LIMIT;
 229         }
 230         Params(SharedPreferences backendPref, String accountsRoot) {
 231             this(backendPref, accountsRoot, DEFAULT_LIMIT);
 232         }
 233         Params(SharedPreferences backendPref, String accountsRoot, int limit) {
 234             this.backendPref = backendPref;
 235             this.accountsRoot = accountsRoot;
 236             this.limit = limit;
 237         }
 238         String getAccountsRoot() {
 239             return accountsRoot;
 240         }
 241         SharedPreferences getBackendPref() {
 242             return backendPref;
 243         }
 244         int getLimit() {
 245             return limit;
 246         }
 247     }
 248
 249     public class Progress {
 250         public static final int INDETERMINATE = -1;
 251         private int progress;
 252         private int total;
 253         Progress() {
 254             this(INDETERMINATE, INDETERMINATE);
 255         }
 256         Progress(int progress, int total) {
 257             this.progress = progress;
 258             this.total = total;
 259         }
 260         public int getProgress() {
 261             return progress;
 262         }
 263         protected void setProgress(int progress) {
 264             this.progress = progress;
 265         }
 266         public int getTotal() {
 267             return total;
 268         }
 269         protected void setTotal(int total) {
 270             this.total = total;
 271         }
 272     }
 273
 274     private class TransactionParserException extends IllegalStateException {
 275         TransactionParserException(String message) {
 276             super(message);
 277         }
 278     }
 279
 280     private class ParserState {
 281         static final int EXPECTING_JOURNAL = 0;
 282         static final int EXPECTING_TRANSACTION = 1;
 283         static final int EXPECTING_TRANSACTION_DESCRIPTION = 2;
 284         static final int EXPECTING_TRANSACTION_DETAILS = 3;
 285     }
 286 }