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.SharedPreferences;
  22 import android.database.sqlite.SQLiteDatabase;
  23 import android.os.AsyncTask;
  24 import android.util.Log;
  25
  26 import net.ktnx.mobileledger.R;
  27 import net.ktnx.mobileledger.TransactionListActivity;
  28 import net.ktnx.mobileledger.model.LedgerTransaction;
  29 import net.ktnx.mobileledger.model.LedgerTransactionItem;
  30 import net.ktnx.mobileledger.utils.MLDB;
  31 import net.ktnx.mobileledger.utils.NetworkUtil;
  32
  33 import java.io.BufferedReader;
  34 import java.io.FileNotFoundException;
  35 import java.io.IOException;
  36 import java.io.InputStream;
  37 import java.io.InputStreamReader;
  38 import java.lang.ref.WeakReference;
  39 import java.net.HttpURLConnection;
  40 import java.net.MalformedURLException;
  41 import java.util.regex.Matcher;
  42 import java.util.regex.Pattern;
  43
  44
  45 public class RetrieveTransactionsTask extends
  46         AsyncTask<RetrieveTransactionsTask.Params, RetrieveTransactionsTask.Progress, Void> {
  47     private static final Pattern transactionStartPattern = Pattern.compile("<tr class=\"title\" " +
  48                                                                            "id=\"transaction-(\\d+)\"><td class=\"date\"[^\\\"]*>([\\d.-]+)</td>");
  49     private static final Pattern transactionDescriptionPattern =
  50             Pattern.compile("<tr class=\"posting\" title=\"(\\S+)\\s(.+)");
  51     private static final Pattern transactionDetailsPattern =
  52             Pattern.compile("^\\s+" + "(\\S[\\S\\s]+\\S)\\s\\s+([-+]?\\d[\\d,.]*)");
  53     private static final Pattern endPattern = Pattern.compile("\\bid=\"addmodal\"");
  54     protected WeakReference<TransactionListActivity> contextRef;
  55     protected int error;
  56     private boolean success;
  57     public RetrieveTransactionsTask(WeakReference<TransactionListActivity> contextRef) {
  58         this.contextRef = contextRef;
  59     }
  60     private static final void L(String msg) {
  61         Log.d("transaction-parser", msg);
  62     }
  63     @Override
  64     protected void onProgressUpdate(Progress... values) {
  65         super.onProgressUpdate(values);
  66         TransactionListActivity context = getContext();
  67         if (context == null) return;
  68         context.onRetrieveProgress(values[0]);
  69     }
  70     @Override
  71     protected void onPreExecute() {
  72         super.onPreExecute();
  73         TransactionListActivity context = getContext();
  74         if (context == null) return;
  75         context.onRetrieveStart();
  76     }
  77     @Override
  78     protected void onPostExecute(Void aVoid) {
  79         super.onPostExecute(aVoid);
  80         TransactionListActivity context = getContext();
  81         if (context == null) return;
  82         context.onRetrieveDone(success);
  83     }
  84     @SuppressLint("DefaultLocale")
  85     @Override
  86     protected Void doInBackground(Params... params) {
  87         Progress progress = new Progress();
  88         success = false;
  89         try {
  90             HttpURLConnection http =
  91                     NetworkUtil.prepare_connection(params[0].getBackendPref(), "journal");
  92             http.setAllowUserInteraction(false);
  93             publishProgress(progress);
  94             TransactionListActivity ctx = contextRef.get();
  95             if (ctx == null) return null;
  96             try (SQLiteDatabase db = MLDB.getWritableDatabase(ctx)) {
  97                 try (InputStream resp = http.getInputStream()) {
  98                     if (http.getResponseCode() != 200) throw new IOException(
  99                             String.format("HTTP error %d", http.getResponseCode()));
 100                     db.beginTransaction();
 101                     try {
 102                         db.execSQL("DELETE FROM transactions;");
 103                         db.execSQL("DELETE FROM transaction_accounts");
 104
 105                         int state = ParserState.EXPECTING_JOURNAL;
 106                         String line;
 107                         BufferedReader buf =
 108                                 new BufferedReader(new InputStreamReader(resp, "UTF-8"));
 109
 110                         int transactionCount = 0;
 111                         int transactionId = 0;
 112                         LedgerTransaction transaction = null;
 113                         LINES:
 114                         while ((line = buf.readLine()) != null) {
 115                             if (isCancelled()) break;
 116                             Matcher m;
 117                             //L(String.format("State is %d", state));
 118                             switch (state) {
 119                                 case ParserState.EXPECTING_JOURNAL:
 120                                     if (!line.isEmpty() && (line.charAt(0) == ' ')) continue;
 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                                     if (!line.isEmpty() && (line.charAt(0) == ' ')) continue;
 128                                     m = transactionStartPattern.matcher(line);
 129                                     if (m.find()) {
 130                                         transactionId = Integer.valueOf(m.group(1));
 131                                         state = ParserState.EXPECTING_TRANSACTION_DESCRIPTION;
 132                                         L(String.format(
 133                                                 "found transaction %d → expecting " + "description",
 134                                                 transactionId));
 135                                         progress.setProgress(++transactionCount);
 136                                         if (progress.getTotal() == Progress.INDETERMINATE)
 137                                             progress.setTotal(transactionId);
 138                                         publishProgress(progress);
 139                                     }
 140                                     m = endPattern.matcher(line);
 141                                     if (m.find()) {
 142                                         L("--- transaction list complete ---");
 143                                         success = true;
 144                                         break LINES;
 145                                     }
 146                                     break;
 147                                 case ParserState.EXPECTING_TRANSACTION_DESCRIPTION:
 148                                     if (!line.isEmpty() && (line.charAt(0) == ' ')) continue;
 149                                     m = transactionDescriptionPattern.matcher(line);
 150                                     if (m.find()) {
 151                                         if (transactionId == 0)
 152                                             throw new TransactionParserException(
 153                                                     "Transaction Id is 0 while expecting " +
 154                                                     "description");
 155
 156                                         transaction =
 157                                                 new LedgerTransaction(transactionId, m.group(1),
 158                                                         m.group(2));
 159                                         state = ParserState.EXPECTING_TRANSACTION_DETAILS;
 160                                         L(String.format("transaction %d created for %s (%s) →" +
 161                                                         " expecting details", transactionId,
 162                                                 m.group(1), m.group(2)));
 163                                     }
 164                                     break;
 165                                 case ParserState.EXPECTING_TRANSACTION_DETAILS:
 166                                     if (line.isEmpty()) {
 167                                         // transaction data collected
 168                                         transaction.insertInto(db);
 169
 170                                         state = ParserState.EXPECTING_TRANSACTION;
 171                                         L(String.format(
 172                                                 "transaction %s saved → expecting " + "transaction",
 173                                                 transaction.getId()));
 174
 175 // sounds like a good idea, but transaction-1 may not be the first one chronologically
 176 // for example, when you add the initial seeding transaction after entering some others
 177 //                                            if (transactionId == 1) {
 178 //                                                L("This was the initial transaction. Terminating " +
 179 //                                                  "parser");
 180 //                                                break LINES;
 181 //                                            }
 182                                     }
 183                                     else {
 184                                         m = transactionDetailsPattern.matcher(line);
 185                                         if (m.find()) {
 186                                             String acc_name = m.group(1);
 187                                             String amount = m.group(2);
 188                                             amount = amount.replace(',', '.');
 189                                             transaction.add_item(new LedgerTransactionItem(acc_name,
 190                                                     Float.valueOf(amount)));
 191                                             L(String.format("%s = %s", acc_name, amount));
 192                                         }
 193                                         else throw new IllegalStateException(
 194                                                 String.format("Can't parse transaction details"));
 195                                     }
 196                                     break;
 197                                 default:
 198                                     throw new RuntimeException(
 199                                             String.format("Unknown " + "parser state %d", state));
 200                             }
 201                         }
 202                         if (!isCancelled()) db.setTransactionSuccessful();
 203                     }
 204                     finally {
 205                         db.endTransaction();
 206                     }
 207                 }
 208             }
 209
 210             if (success && !isCancelled()) ctx.model.reloadTransactions(ctx);
 211         }
 212         catch (MalformedURLException e) {
 213             error = R.string.err_bad_backend_url;
 214             e.printStackTrace();
 215         }
 216         catch (FileNotFoundException e) {
 217             error = R.string.err_bad_auth;
 218             e.printStackTrace();
 219         }
 220         catch (IOException e) {
 221             error = R.string.err_net_io_error;
 222             e.printStackTrace();
 223         }
 224         return null;
 225     }
 226     TransactionListActivity getContext() {
 227         return contextRef.get();
 228     }
 229
 230     public static class Params {
 231         static final int DEFAULT_LIMIT = 100;
 232         private SharedPreferences backendPref;
 233         private String accountsRoot;
 234         private int limit;
 235
 236         public Params(SharedPreferences backendPref) {
 237             this.backendPref = backendPref;
 238             this.accountsRoot = null;
 239             this.limit = DEFAULT_LIMIT;
 240         }
 241         Params(SharedPreferences backendPref, String accountsRoot) {
 242             this(backendPref, accountsRoot, DEFAULT_LIMIT);
 243         }
 244         Params(SharedPreferences backendPref, String accountsRoot, int limit) {
 245             this.backendPref = backendPref;
 246             this.accountsRoot = accountsRoot;
 247             this.limit = limit;
 248         }
 249         String getAccountsRoot() {
 250             return accountsRoot;
 251         }
 252         SharedPreferences getBackendPref() {
 253             return backendPref;
 254         }
 255         int getLimit() {
 256             return limit;
 257         }
 258     }
 259
 260     public class Progress {
 261         public static final int INDETERMINATE = -1;
 262         private int progress;
 263         private int total;
 264         Progress() {
 265             this(INDETERMINATE, INDETERMINATE);
 266         }
 267         Progress(int progress, int total) {
 268             this.progress = progress;
 269             this.total = total;
 270         }
 271         public int getProgress() {
 272             return progress;
 273         }
 274         protected void setProgress(int progress) {
 275             this.progress = progress;
 276         }
 277         public int getTotal() {
 278             return total;
 279         }
 280         protected void setTotal(int total) {
 281             this.total = total;
 282         }
 283     }
 284
 285     private class TransactionParserException extends IllegalStateException {
 286         TransactionParserException(String message) {
 287             super(message);
 288         }
 289     }
 290
 291     private class ParserState {
 292         static final int EXPECTING_JOURNAL = 0;
 293         static final int EXPECTING_TRANSACTION = 1;
 294         static final int EXPECTING_TRANSACTION_DESCRIPTION = 2;
 295         static final int EXPECTING_TRANSACTION_DETAILS = 3;
 296     }
 297 }