app/src/main/java/net/ktnx/mobileledger/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;
  19
  20 import android.content.Context;
  21 import android.content.SharedPreferences;
  22 import android.database.sqlite.SQLiteDatabase;
  23 import android.os.AsyncTask;
  24
  25 import java.io.BufferedReader;
  26 import java.io.FileNotFoundException;
  27 import java.io.IOException;
  28 import java.io.InputStream;
  29 import java.io.InputStreamReader;
  30 import java.lang.ref.WeakReference;
  31 import java.net.HttpURLConnection;
  32 import java.net.MalformedURLException;
  33 import java.util.regex.Matcher;
  34 import java.util.regex.Pattern;
  35
  36 class Params {
  37     static final int DEFAULT_LIMIT = 100;
  38     private SharedPreferences backendPref;
  39     private String accountsRoot;
  40     private int limit;
  41
  42     Params(SharedPreferences backendPref) {
  43         this.backendPref = backendPref;
  44         this.accountsRoot = null;
  45         this.limit = DEFAULT_LIMIT;
  46     }
  47     Params(SharedPreferences backendPref, String accountsRoot) {
  48         this(backendPref, accountsRoot, DEFAULT_LIMIT);
  49     }
  50     Params(SharedPreferences backendPref, String accountsRoot, int limit) {
  51         this.backendPref = backendPref;
  52         this.accountsRoot = accountsRoot;
  53         this.limit = limit;
  54     }
  55     String getAccountsRoot() {
  56         return accountsRoot;
  57     }
  58     SharedPreferences getBackendPref() {
  59         return backendPref;
  60     }
  61     int getLimit() {
  62         return limit;
  63     }
  64 }
  65
  66 class RetrieveTransactionsTask extends AsyncTask<Params, Integer, Void> {
  67     private static final Pattern transactionStartPattern = Pattern.compile("<tr class=\"title\" "
  68             + "id=\"transaction-(\\d+)\"><td class=\"date\"[^\\\"]*>([\\d.-]+)</td>");
  69     private static final Pattern transactionDescriptionPattern =
  70             Pattern.compile("<tr class=\"posting\" title=\"(\\S+)\\s(.+)");
  71     private static final Pattern transactionDetailsPattern =
  72             Pattern.compile("^\\s+" + "(\\S[\\S\\s]+\\S)\\s\\s+([-+]?\\d[\\d,.]*)");
  73     protected WeakReference<Context> contextRef;
  74     protected int error;
  75     @Override
  76     protected Void doInBackground(Params... params) {
  77         try {
  78             HttpURLConnection http =
  79                     NetworkUtil.prepare_connection(params[0].getBackendPref(), "journal");
  80             http.setAllowUserInteraction(false);
  81             publishProgress(0);
  82             Context ctx = contextRef.get();
  83             if (ctx == null) return null;
  84             try (MobileLedgerDatabase dbh = new MobileLedgerDatabase(ctx)) {
  85                 try (SQLiteDatabase db = dbh.getWritableDatabase()) {
  86                     try (InputStream resp = http.getInputStream()) {
  87                         if (http.getResponseCode() != 200) throw new IOException(
  88                                 String.format("HTTP error %d", http.getResponseCode()));
  89                         db.beginTransaction();
  90                         try {
  91                             String root = params[0].getAccountsRoot();
  92                             if (root == null) db.execSQL("DELETE FROM transaction_history;");
  93                             else {
  94                                 StringBuilder sql = new StringBuilder();
  95                                 sql.append("DELETE FROM transaction_history ");
  96                                 sql.append(
  97                                         "where id in (select transactions.id from transactions ");
  98                                 sql.append("join transaction_accounts ");
  99                                 sql.append(
 100                                         "on transactions.id=transaction_accounts.transaction_id ");
 101                                 sql.append("where transaction_accounts.account_name like ?||'%'");
 102                                 db.execSQL(sql.toString(), new String[]{root});
 103                             }
 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                             String transactionId = null;
 112                             LedgerTransaction transaction = null;
 113                             while ((line = buf.readLine()) != null) {
 114                                 switch (state) {
 115                                     case ParserState.EXPECTING_JOURNAL: {
 116                                         if (line.equals("<h2>General Journal</h2>"))
 117                                             state = ParserState.EXPECTING_TRANSACTION;
 118                                         continue;
 119                                     }
 120                                     case ParserState.EXPECTING_TRANSACTION: {
 121                                         Matcher m = transactionStartPattern.matcher(line);
 122                                         if (m.find()) {
 123                                             transactionId = m.group(1);
 124                                             state = ParserState.EXPECTING_TRANSACTION_DESCRIPTION;
 125                                         }
 126                                     }
 127                                     case ParserState.EXPECTING_TRANSACTION_DESCRIPTION: {
 128                                         Matcher m = transactionDescriptionPattern.matcher(line);
 129                                         if (m.find()) {
 130                                             if (transactionId == null)
 131                                                 throw new TransactionParserException(
 132                                                         "Transaction Id is null while expecting description");
 133
 134                                             transaction =
 135                                                     new LedgerTransaction(transactionId, m.group(1),
 136                                                             m.group(2));
 137                                             state = ParserState.EXPECTING_TRANSACTION_DETAILS;
 138                                         }
 139                                     }
 140                                     case ParserState.EXPECTING_TRANSACTION_DETAILS: {
 141                                         if (transaction == null)
 142                                             throw new TransactionParserException(
 143                                                     "Transaction is null while expecting details");
 144                                         if (line.isEmpty()) {
 145                                             // transaction data collected
 146                                             transaction.insertInto(db);
 147
 148                                             state = ParserState.EXPECTING_TRANSACTION;
 149                                             publishProgress(++transactionCount);
 150                                         }
 151                                         else {
 152                                             Matcher m = transactionDetailsPattern.matcher(line);
 153                                             if (m.find()) {
 154                                                 String acc_name = m.group(1);
 155                                                 String amount = m.group(2);
 156                                                 amount = amount.replace(',', '.');
 157                                                 transaction.add_item(
 158                                                         new LedgerTransactionItem(acc_name,
 159                                                                 Float.valueOf(amount)));
 160                                             }
 161                                             else throw new IllegalStateException(String.format(
 162                                                     "Can't" + " parse transaction details"));
 163                                         }
 164                                     }
 165                                     default:
 166                                         throw new RuntimeException(
 167                                                 String.format("Unknown " + "parser state %d",
 168                                                         state));
 169                                 }
 170                             }
 171                             db.setTransactionSuccessful();
 172                         }
 173                         finally {
 174                             db.endTransaction();
 175                         }
 176                     }
 177                 }
 178             }
 179         }
 180         catch (MalformedURLException e) {
 181             error = R.string.err_bad_backend_url;
 182             e.printStackTrace();
 183         }
 184         catch (FileNotFoundException e) {
 185             error = R.string.err_bad_auth;
 186             e.printStackTrace();
 187         }
 188         catch (IOException e) {
 189             error = R.string.err_net_io_error;
 190             e.printStackTrace();
 191         }
 192         return null;
 193     }
 194     WeakReference<Context> getContextRef() {
 195         return contextRef;
 196     }
 197
 198     private class TransactionParserException extends IllegalStateException {
 199         TransactionParserException(String message) {
 200             super(message);
 201         }
 202     }
 203
 204     private class ParserState {
 205         static final int EXPECTING_JOURNAL = 0;
 206         static final int EXPECTING_TRANSACTION = 1;
 207         static final int EXPECTING_TRANSACTION_DESCRIPTION = 2;
 208         static final int EXPECTING_TRANSACTION_DETAILS = 3;
 209     }
 210 }