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.content.Context;
  21 import android.content.SharedPreferences;
  22 import android.database.sqlite.SQLiteDatabase;
  23 import android.os.AsyncTask;
  24
  25 import net.ktnx.mobileledger.R;
  26 import net.ktnx.mobileledger.model.LedgerTransaction;
  27 import net.ktnx.mobileledger.model.LedgerTransactionItem;
  28 import net.ktnx.mobileledger.utils.MobileLedgerDatabase;
  29 import net.ktnx.mobileledger.utils.NetworkUtil;
  30
  31 import java.io.BufferedReader;
  32 import java.io.FileNotFoundException;
  33 import java.io.IOException;
  34 import java.io.InputStream;
  35 import java.io.InputStreamReader;
  36 import java.lang.ref.WeakReference;
  37 import java.net.HttpURLConnection;
  38 import java.net.MalformedURLException;
  39 import java.util.regex.Matcher;
  40 import java.util.regex.Pattern;
  41
  42
  43 class RetrieveTransactionsTask extends AsyncTask<RetrieveTransactionsTask.Params, Integer, Void> {
  44     class Params {
  45         static final int DEFAULT_LIMIT = 100;
  46         private SharedPreferences backendPref;
  47         private String accountsRoot;
  48         private int limit;
  49
  50         Params(SharedPreferences backendPref) {
  51             this.backendPref = backendPref;
  52             this.accountsRoot = null;
  53             this.limit = DEFAULT_LIMIT;
  54         }
  55         Params(SharedPreferences backendPref, String accountsRoot) {
  56             this(backendPref, accountsRoot, DEFAULT_LIMIT);
  57         }
  58         Params(SharedPreferences backendPref, String accountsRoot, int limit) {
  59             this.backendPref = backendPref;
  60             this.accountsRoot = accountsRoot;
  61             this.limit = limit;
  62         }
  63         String getAccountsRoot() {
  64             return accountsRoot;
  65         }
  66         SharedPreferences getBackendPref() {
  67             return backendPref;
  68         }
  69         int getLimit() {
  70             return limit;
  71         }
  72     }
  73     private static final Pattern transactionStartPattern = Pattern.compile("<tr class=\"title\" "
  74             + "id=\"transaction-(\\d+)\"><td class=\"date\"[^\\\"]*>([\\d.-]+)</td>");
  75     private static final Pattern transactionDescriptionPattern =
  76             Pattern.compile("<tr class=\"posting\" title=\"(\\S+)\\s(.+)");
  77     private static final Pattern transactionDetailsPattern =
  78             Pattern.compile("^\\s+" + "(\\S[\\S\\s]+\\S)\\s\\s+([-+]?\\d[\\d,.]*)");
  79     protected WeakReference<Context> contextRef;
  80     protected int error;
  81     @Override
  82     protected Void doInBackground(Params... params) {
  83         try {
  84             HttpURLConnection http =
  85                     NetworkUtil.prepare_connection(params[0].getBackendPref(), "journal");
  86             http.setAllowUserInteraction(false);
  87             publishProgress(0);
  88             Context ctx = contextRef.get();
  89             if (ctx == null) return null;
  90             try (MobileLedgerDatabase dbh = new MobileLedgerDatabase(ctx)) {
  91                 try (SQLiteDatabase db = dbh.getWritableDatabase()) {
  92                     try (InputStream resp = http.getInputStream()) {
  93                         if (http.getResponseCode() != 200) throw new IOException(
  94                                 String.format("HTTP error %d", http.getResponseCode()));
  95                         db.beginTransaction();
  96                         try {
  97                             String root = params[0].getAccountsRoot();
  98                             if (root == null) db.execSQL("DELETE FROM transaction_history;");
  99                             else {
 100                                 StringBuilder sql = new StringBuilder();
 101                                 sql.append("DELETE FROM transaction_history ");
 102                                 sql.append(
 103                                         "where id in (select transactions.id from transactions ");
 104                                 sql.append("join transaction_accounts ");
 105                                 sql.append(
 106                                         "on transactions.id=transaction_accounts.transaction_id ");
 107                                 sql.append("where transaction_accounts.account_name like ?||'%'");
 108                                 db.execSQL(sql.toString(), new String[]{root});
 109                             }
 110
 111                             int state = ParserState.EXPECTING_JOURNAL;
 112                             String line;
 113                             BufferedReader buf =
 114                                     new BufferedReader(new InputStreamReader(resp, "UTF-8"));
 115
 116                             int transactionCount = 0;
 117                             String transactionId = null;
 118                             LedgerTransaction transaction = null;
 119                             while ((line = buf.readLine()) != null) {
 120                                 switch (state) {
 121                                     case ParserState.EXPECTING_JOURNAL: {
 122                                         if (line.equals("<h2>General Journal</h2>"))
 123                                             state = ParserState.EXPECTING_TRANSACTION;
 124                                         continue;
 125                                     }
 126                                     case ParserState.EXPECTING_TRANSACTION: {
 127                                         Matcher m = transactionStartPattern.matcher(line);
 128                                         if (m.find()) {
 129                                             transactionId = m.group(1);
 130                                             state = ParserState.EXPECTING_TRANSACTION_DESCRIPTION;
 131                                         }
 132                                     }
 133                                     case ParserState.EXPECTING_TRANSACTION_DESCRIPTION: {
 134                                         Matcher m = transactionDescriptionPattern.matcher(line);
 135                                         if (m.find()) {
 136                                             if (transactionId == null)
 137                                                 throw new TransactionParserException(
 138                                                         "Transaction Id is null while expecting description");
 139
 140                                             transaction =
 141                                                     new LedgerTransaction(transactionId, m.group(1),
 142                                                             m.group(2));
 143                                             state = ParserState.EXPECTING_TRANSACTION_DETAILS;
 144                                         }
 145                                     }
 146                                     case ParserState.EXPECTING_TRANSACTION_DETAILS: {
 147                                         if (transaction == null)
 148                                             throw new TransactionParserException(
 149                                                     "Transaction is null while expecting details");
 150                                         if (line.isEmpty()) {
 151                                             // transaction data collected
 152                                             transaction.insertInto(db);
 153
 154                                             state = ParserState.EXPECTING_TRANSACTION;
 155                                             publishProgress(++transactionCount);
 156                                         }
 157                                         else {
 158                                             Matcher m = transactionDetailsPattern.matcher(line);
 159                                             if (m.find()) {
 160                                                 String acc_name = m.group(1);
 161                                                 String amount = m.group(2);
 162                                                 amount = amount.replace(',', '.');
 163                                                 transaction.add_item(
 164                                                         new LedgerTransactionItem(acc_name,
 165                                                                 Float.valueOf(amount)));
 166                                             }
 167                                             else throw new IllegalStateException(String.format(
 168                                                     "Can't" + " parse transaction details"));
 169                                         }
 170                                     }
 171                                     default:
 172                                         throw new RuntimeException(
 173                                                 String.format("Unknown " + "parser state %d",
 174                                                         state));
 175                                 }
 176                             }
 177                             db.setTransactionSuccessful();
 178                         }
 179                         finally {
 180                             db.endTransaction();
 181                         }
 182                     }
 183                 }
 184             }
 185         }
 186         catch (MalformedURLException e) {
 187             error = R.string.err_bad_backend_url;
 188             e.printStackTrace();
 189         }
 190         catch (FileNotFoundException e) {
 191             error = R.string.err_bad_auth;
 192             e.printStackTrace();
 193         }
 194         catch (IOException e) {
 195             error = R.string.err_net_io_error;
 196             e.printStackTrace();
 197         }
 198         return null;
 199     }
 200     WeakReference<Context> getContextRef() {
 201         return contextRef;
 202     }
 203
 204     private class TransactionParserException extends IllegalStateException {
 205         TransactionParserException(String message) {
 206             super(message);
 207         }
 208     }
 209
 210     private class ParserState {
 211         static final int EXPECTING_JOURNAL = 0;
 212         static final int EXPECTING_TRANSACTION = 1;
 213         static final int EXPECTING_TRANSACTION_DESCRIPTION = 2;
 214         static final int EXPECTING_TRANSACTION_DETAILS = 3;
 215     }
 216 }