app/src/main/java/net/ktnx/mobileledger/ui/new_transaction/NewTransactionModel.java

   1 /*
   2  * Copyright © 2021 Damyan Ivanov.
   3  * This file is part of MoLe.
   4  * MoLe 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  * MoLe 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 MoLe. If not, see <https://www.gnu.org/licenses/>.
  16  */
  17
  18 package net.ktnx.mobileledger.ui.new_transaction;
  19
  20 import android.annotation.SuppressLint;
  21 import android.text.TextUtils;
  22
  23 import androidx.annotation.NonNull;
  24 import androidx.annotation.Nullable;
  25 import androidx.lifecycle.LifecycleOwner;
  26 import androidx.lifecycle.LiveData;
  27 import androidx.lifecycle.MutableLiveData;
  28 import androidx.lifecycle.Observer;
  29 import androidx.lifecycle.ViewModel;
  30
  31 import net.ktnx.mobileledger.BuildConfig;
  32 import net.ktnx.mobileledger.db.Currency;
  33 import net.ktnx.mobileledger.db.DB;
  34 import net.ktnx.mobileledger.db.Profile;
  35 import net.ktnx.mobileledger.db.TemplateAccount;
  36 import net.ktnx.mobileledger.db.TemplateHeader;
  37 import net.ktnx.mobileledger.db.TransactionWithAccounts;
  38 import net.ktnx.mobileledger.model.Data;
  39 import net.ktnx.mobileledger.model.InertMutableLiveData;
  40 import net.ktnx.mobileledger.model.LedgerTransaction;
  41 import net.ktnx.mobileledger.model.LedgerTransactionAccount;
  42 import net.ktnx.mobileledger.model.MatchedTemplate;
  43 import net.ktnx.mobileledger.utils.Globals;
  44 import net.ktnx.mobileledger.utils.Logger;
  45 import net.ktnx.mobileledger.utils.Misc;
  46 import net.ktnx.mobileledger.utils.SimpleDate;
  47
  48 import org.jetbrains.annotations.NotNull;
  49
  50 import java.text.ParseException;
  51 import java.util.ArrayList;
  52 import java.util.Calendar;
  53 import java.util.GregorianCalendar;
  54 import java.util.HashMap;
  55 import java.util.List;
  56 import java.util.Locale;
  57 import java.util.Objects;
  58 import java.util.Set;
  59 import java.util.concurrent.atomic.AtomicInteger;
  60 import java.util.regex.MatchResult;
  61
  62 enum ItemType {generalData, transactionRow}
  63
  64 enum FocusedElement {Account, Comment, Amount, Description, TransactionComment}
  65
  66
  67 public class NewTransactionModel extends ViewModel {
  68     private static final int MIN_ITEMS = 3;
  69     private final MutableLiveData<Boolean> showCurrency = new MutableLiveData<>(false);
  70     private final MutableLiveData<Boolean> isSubmittable = new InertMutableLiveData<>(false);
  71     private final MutableLiveData<Boolean> showComments = new MutableLiveData<>(true);
  72     private final MutableLiveData<List<Item>> items = new MutableLiveData<>();
  73     private final MutableLiveData<Boolean> simulateSave = new InertMutableLiveData<>(false);
  74     private final AtomicInteger busyCounter = new AtomicInteger(0);
  75     private final MutableLiveData<Boolean> busyFlag = new InertMutableLiveData<>(false);
  76     private final Observer<Profile> profileObserver = profile -> {
  77         if (profile != null) {
  78             showCurrency.postValue(profile.getShowCommodityByDefault());
  79             showComments.postValue(profile.getShowCommentsByDefault());
  80         }
  81     };
  82     private final MutableLiveData<FocusInfo> focusInfo = new MutableLiveData<>();
  83     private boolean observingDataProfile;
  84     public NewTransactionModel() {
  85     }
  86     public LiveData<Boolean> getShowCurrency() {
  87         return showCurrency;
  88     }
  89     public LiveData<List<Item>> getItems() {
  90         return items;
  91     }
  92     private void setItems(@NonNull List<Item> newList) {
  93         checkTransactionSubmittable(newList);
  94         setItemsWithoutSubmittableChecks(newList);
  95     }
  96     private void replaceItems(@NonNull List<Item> newList) {
  97         renumberItems();
  98
  99         setItems(newList);
 100     }
 101     /**
 102      * make old items replaceable in-place. makes the new values visually blend in
 103      */
 104     private void renumberItems() {
 105         renumberItems(items.getValue());
 106     }
 107     private void renumberItems(List<Item> list) {
 108         if (list == null) {
 109             return;
 110         }
 111
 112         int id = 0;
 113         for (Item item : list)
 114             item.id = id++;
 115     }
 116     private void setItemsWithoutSubmittableChecks(@NonNull List<Item> list) {
 117         final int cnt = list.size();
 118         for (int i = 1; i < cnt - 1; i++) {
 119             final TransactionAccount item = list.get(i)
 120                                                 .toTransactionAccount();
 121             if (item.isLast) {
 122                 TransactionAccount replacement = new TransactionAccount(item);
 123                 replacement.isLast = false;
 124                 list.set(i, replacement);
 125             }
 126         }
 127         final TransactionAccount last = list.get(cnt - 1)
 128                                             .toTransactionAccount();
 129         if (!last.isLast) {
 130             TransactionAccount replacement = new TransactionAccount(last);
 131             replacement.isLast = true;
 132             list.set(cnt - 1, replacement);
 133         }
 134
 135         if (BuildConfig.DEBUG)
 136             dumpItemList("Before setValue()", list);
 137         items.setValue(list);
 138     }
 139     private List<Item> copyList() {
 140         List<Item> copy = new ArrayList<>();
 141         List<Item> oldList = items.getValue();
 142
 143         if (oldList != null)
 144             for (Item item : oldList) {
 145                 copy.add(Item.from(item));
 146             }
 147
 148         return copy;
 149     }
 150     private List<Item> copyListWithoutItem(int position) {
 151         List<Item> copy = new ArrayList<>();
 152         List<Item> oldList = items.getValue();
 153
 154         if (oldList != null) {
 155             int i = 0;
 156             for (Item item : oldList) {
 157                 if (i++ == position)
 158                     continue;
 159                 copy.add(Item.from(item));
 160             }
 161         }
 162
 163         return copy;
 164     }
 165     private List<Item> shallowCopyList() {
 166         return new ArrayList<>(Objects.requireNonNull(items.getValue()));
 167     }
 168     LiveData<Boolean> getShowComments() {
 169         return showComments;
 170     }
 171     void observeDataProfile(LifecycleOwner activity) {
 172         if (!observingDataProfile)
 173             Data.observeProfile(activity, profileObserver);
 174         observingDataProfile = true;
 175     }
 176     boolean getSimulateSaveFlag() {
 177         Boolean value = simulateSave.getValue();
 178         if (value == null)
 179             return false;
 180         return value;
 181     }
 182     LiveData<Boolean> getSimulateSave() {
 183         return simulateSave;
 184     }
 185     void toggleSimulateSave() {
 186         simulateSave.setValue(!getSimulateSaveFlag());
 187     }
 188     LiveData<Boolean> isSubmittable() {
 189         return this.isSubmittable;
 190     }
 191     void reset() {
 192         Logger.debug("new-trans", "Resetting model");
 193         List<Item> list = new ArrayList<>();
 194         Item.resetIdDispenser();
 195         list.add(new TransactionHead(""));
 196         final String defaultCurrency = Objects.requireNonNull(Data.getProfile())
 197                                               .getDefaultCommodity();
 198         list.add(new TransactionAccount("", defaultCurrency));
 199         list.add(new TransactionAccount("", defaultCurrency));
 200         noteFocusChanged(0, FocusedElement.Description);
 201         renumberItems();
 202         isSubmittable.setValue(false);
 203         setItemsWithoutSubmittableChecks(list);
 204     }
 205     boolean accountsInInitialState() {
 206         final List<Item> list = items.getValue();
 207
 208         if (list == null)
 209             return true;
 210
 211         for (Item item : list) {
 212             if (!(item instanceof TransactionAccount))
 213                 continue;
 214
 215             TransactionAccount accRow = (TransactionAccount) item;
 216             if (!accRow.isEmpty())
 217                 return false;
 218         }
 219
 220         return true;
 221     }
 222     void applyTemplate(MatchedTemplate matchedTemplate, String text) {
 223         SimpleDate transactionDate = null;
 224         final MatchResult matchResult = matchedTemplate.matchResult;
 225         final TemplateHeader templateHead = matchedTemplate.templateHead;
 226         {
 227             int day = extractIntFromMatches(matchResult, templateHead.getDateDayMatchGroup(),
 228                     templateHead.getDateDay());
 229             int month = extractIntFromMatches(matchResult, templateHead.getDateMonthMatchGroup(),
 230                     templateHead.getDateMonth());
 231             int year = extractIntFromMatches(matchResult, templateHead.getDateYearMatchGroup(),
 232                     templateHead.getDateYear());
 233
 234             if (year > 0 || month > 0 || day > 0) {
 235                 SimpleDate today = SimpleDate.today();
 236                 if (year <= 0)
 237                     year = today.year;
 238                 if (month <= 0)
 239                     month = today.month;
 240                 if (day <= 0)
 241                     day = today.day;
 242
 243                 transactionDate = new SimpleDate(year, month, day);
 244
 245                 Logger.debug("pattern", "setting transaction date to " + transactionDate);
 246             }
 247         }
 248
 249         List<Item> present = copyList();
 250
 251         TransactionHead head = new TransactionHead(present.get(0)
 252                                                           .toTransactionHead());
 253         if (transactionDate != null)
 254             head.setDate(transactionDate);
 255
 256         final String transactionDescription = extractStringFromMatches(matchResult,
 257                 templateHead.getTransactionDescriptionMatchGroup(),
 258                 templateHead.getTransactionDescription());
 259         if (Misc.emptyIsNull(transactionDescription) != null)
 260             head.setDescription(transactionDescription);
 261
 262         final String transactionComment = extractStringFromMatches(matchResult,
 263                 templateHead.getTransactionCommentMatchGroup(),
 264                 templateHead.getTransactionComment());
 265         if (Misc.emptyIsNull(transactionComment) != null)
 266             head.setComment(transactionComment);
 267
 268         List<Item> newItems = new ArrayList<>();
 269
 270         newItems.add(head);
 271
 272         for (int i = 1; i < present.size(); i++) {
 273             final TransactionAccount row = present.get(i)
 274                                                   .toTransactionAccount();
 275             if (!row.isEmpty())
 276                 newItems.add(new TransactionAccount(row));
 277         }
 278
 279         DB.get()
 280           .getTemplateDAO()
 281           .getTemplateWithAccountsAsync(templateHead.getId(), entry -> {
 282               int rowIndex = 0;
 283               final boolean accountsInInitialState = accountsInInitialState();
 284               for (TemplateAccount acc : entry.accounts) {
 285                   rowIndex++;
 286
 287                   String accountName =
 288                           extractStringFromMatches(matchResult, acc.getAccountNameMatchGroup(),
 289                                   acc.getAccountName());
 290                   String accountComment =
 291                           extractStringFromMatches(matchResult, acc.getAccountCommentMatchGroup(),
 292                                   acc.getAccountComment());
 293                   Float amount = extractFloatFromMatches(matchResult, acc.getAmountMatchGroup(),
 294                           acc.getAmount());
 295                   if (amount != null && acc.getNegateAmount() != null && acc.getNegateAmount())
 296                       amount = -amount;
 297
 298                   TransactionAccount accRow = new TransactionAccount(accountName);
 299                   accRow.setComment(accountComment);
 300                   if (amount != null)
 301                       accRow.setAmount(amount);
 302                   accRow.setCurrency(
 303                           extractCurrencyFromMatches(matchResult, acc.getCurrencyMatchGroup(),
 304                                   acc.getCurrencyObject()));
 305
 306                   newItems.add(accRow);
 307               }
 308
 309               renumberItems(newItems);
 310               Misc.onMainThread(() -> replaceItems(newItems));
 311           });
 312     }
 313     @NonNull
 314     private String extractCurrencyFromMatches(MatchResult m, Integer group, Currency literal) {
 315         return Misc.nullIsEmpty(
 316                 extractStringFromMatches(m, group, (literal == null) ? "" : literal.getName()));
 317     }
 318     private int extractIntFromMatches(MatchResult m, Integer group, Integer literal) {
 319         if (literal != null)
 320             return literal;
 321
 322         if (group != null) {
 323             int grp = group;
 324             if (grp > 0 && grp <= m.groupCount())
 325                 try {
 326                     return Integer.parseInt(m.group(grp));
 327                 }
 328                 catch (NumberFormatException e) {
 329                     Logger.debug("new-trans", "Error extracting matched number", e);
 330                 }
 331         }
 332
 333         return 0;
 334     }
 335     @Nullable
 336     private String extractStringFromMatches(MatchResult m, Integer group, String literal) {
 337         if (literal != null)
 338             return literal;
 339
 340         if (group != null) {
 341             int grp = group;
 342             if (grp > 0 && grp <= m.groupCount())
 343                 return m.group(grp);
 344         }
 345
 346         return null;
 347     }
 348     private Float extractFloatFromMatches(MatchResult m, Integer group, Float literal) {
 349         if (literal != null)
 350             return literal;
 351
 352         if (group != null) {
 353             int grp = group;
 354             if (grp > 0 && grp <= m.groupCount())
 355                 try {
 356                     return Float.valueOf(m.group(grp));
 357                 }
 358                 catch (NumberFormatException e) {
 359                     Logger.debug("new-trans", "Error extracting matched number", e);
 360                 }
 361         }
 362
 363         return null;
 364     }
 365     void removeItem(int pos) {
 366         Logger.debug("new-trans", String.format(Locale.US, "Removing item at position %d", pos));
 367         List<Item> newList = copyListWithoutItem(pos);
 368         final FocusInfo fi = focusInfo.getValue();
 369         if ((fi != null) && (pos < fi.position))
 370             noteFocusChanged(fi.position - 1, fi.element);
 371         setItems(newList);
 372     }
 373     void noteFocusChanged(int position, @Nullable FocusedElement element) {
 374         FocusInfo present = focusInfo.getValue();
 375         if (present == null || present.position != position || present.element != element)
 376             focusInfo.setValue(new FocusInfo(position, element));
 377     }
 378     public LiveData<FocusInfo> getFocusInfo() {
 379         return focusInfo;
 380     }
 381     void moveItem(int fromIndex, int toIndex) {
 382         List<Item> newList = shallowCopyList();
 383         Item item = newList.remove(fromIndex);
 384         newList.add(toIndex, item);
 385
 386         FocusInfo fi = focusInfo.getValue();
 387         if (fi != null && fi.position == fromIndex)
 388             noteFocusChanged(toIndex, fi.element);
 389
 390         items.setValue(newList); // same count, same submittable state
 391     }
 392     void moveItemLast(List<Item> list, int index) {
 393         /*   0
 394              1   <-- index
 395              2
 396              3   <-- desired position
 397                  (no bottom filler)
 398          */
 399         int itemCount = list.size();
 400
 401         if (index < itemCount - 1)
 402             list.add(list.remove(index));
 403     }
 404     void toggleCurrencyVisible() {
 405         final boolean newValue = !Objects.requireNonNull(showCurrency.getValue());
 406
 407         // remove currency from all items, or reset currency to the default
 408         // no need to clone the list, because the removal of the currency won't lead to
 409         // visual changes -- the currency fields will be hidden or reset to default anyway
 410         // still, there may be changes in the submittable state
 411         final List<Item> list = Objects.requireNonNull(this.items.getValue());
 412         final Profile profile = Objects.requireNonNull(Data.getProfile());
 413         for (int i = 1; i < list.size(); i++) {
 414             ((TransactionAccount) list.get(i)).setCurrency(
 415                     newValue ? profile.getDefaultCommodity() : "");
 416         }
 417         checkTransactionSubmittable(null);
 418         showCurrency.setValue(newValue);
 419     }
 420     void stopObservingBusyFlag(Observer<Boolean> observer) {
 421         busyFlag.removeObserver(observer);
 422     }
 423     void incrementBusyCounter() {
 424         int newValue = busyCounter.incrementAndGet();
 425         if (newValue == 1)
 426             busyFlag.postValue(true);
 427     }
 428     void decrementBusyCounter() {
 429         int newValue = busyCounter.decrementAndGet();
 430         if (newValue == 0)
 431             busyFlag.postValue(false);
 432     }
 433     public LiveData<Boolean> getBusyFlag() {
 434         return busyFlag;
 435     }
 436     public void toggleShowComments() {
 437         showComments.setValue(!Objects.requireNonNull(showComments.getValue()));
 438     }
 439     public LedgerTransaction constructLedgerTransaction() {
 440         List<Item> list = Objects.requireNonNull(items.getValue());
 441         TransactionHead head = list.get(0)
 442                                    .toTransactionHead();
 443         LedgerTransaction tr = head.asLedgerTransaction();
 444
 445         tr.setComment(head.getComment());
 446         LedgerTransactionAccount emptyAmountAccount = null;
 447         float emptyAmountAccountBalance = 0;
 448         for (int i = 1; i < list.size(); i++) {
 449             TransactionAccount item = list.get(i)
 450                                           .toTransactionAccount();
 451             LedgerTransactionAccount acc = new LedgerTransactionAccount(item.getAccountName()
 452                                                                             .trim(),
 453                     item.getCurrency());
 454             if (acc.getAccountName()
 455                    .isEmpty())
 456                 continue;
 457
 458             acc.setComment(item.getComment());
 459
 460             if (item.isAmountSet()) {
 461                 acc.setAmount(item.getAmount());
 462                 emptyAmountAccountBalance += item.getAmount();
 463             }
 464             else {
 465                 emptyAmountAccount = acc;
 466             }
 467
 468             tr.addAccount(acc);
 469         }
 470
 471         if (emptyAmountAccount != null)
 472             emptyAmountAccount.setAmount(-emptyAmountAccountBalance);
 473
 474         return tr;
 475     }
 476     void loadTransactionIntoModel(@NonNull TransactionWithAccounts tr) {
 477         List<Item> newList = new ArrayList<>();
 478         Item.resetIdDispenser();
 479
 480         Item currentHead = Objects.requireNonNull(items.getValue())
 481                                   .get(0);
 482         TransactionHead head = new TransactionHead(tr.transaction.getDescription());
 483         head.setComment(tr.transaction.getComment());
 484         if (currentHead instanceof TransactionHead)
 485             head.setDate(((TransactionHead) currentHead).date);
 486
 487         newList.add(head);
 488
 489         List<LedgerTransactionAccount> accounts = new ArrayList<>();
 490         for (net.ktnx.mobileledger.db.TransactionAccount acc : tr.accounts) {
 491             accounts.add(new LedgerTransactionAccount(acc));
 492         }
 493
 494         TransactionAccount firstNegative = null;
 495         TransactionAccount firstPositive = null;
 496         int singleNegativeIndex = -1;
 497         int singlePositiveIndex = -1;
 498         int negativeCount = 0;
 499         for (int i = 0; i < accounts.size(); i++) {
 500             LedgerTransactionAccount acc = accounts.get(i);
 501             TransactionAccount item = new TransactionAccount(acc.getAccountName(),
 502                     Misc.nullIsEmpty(acc.getCurrency()));
 503             newList.add(item);
 504
 505             item.setAccountName(acc.getAccountName());
 506             item.setComment(acc.getComment());
 507             if (acc.isAmountSet()) {
 508                 item.setAmount(acc.getAmount());
 509                 if (acc.getAmount() < 0) {
 510                     if (firstNegative == null) {
 511                         firstNegative = item;
 512                         singleNegativeIndex = i + 1;
 513                     }
 514                     else
 515                         singleNegativeIndex = -1;
 516                 }
 517                 else {
 518                     if (firstPositive == null) {
 519                         firstPositive = item;
 520                         singlePositiveIndex = i + 1;
 521                     }
 522                     else
 523                         singlePositiveIndex = -1;
 524                 }
 525             }
 526             else
 527                 item.resetAmount();
 528         }
 529         if (BuildConfig.DEBUG)
 530             dumpItemList("Loaded previous transaction", newList);
 531
 532         if (singleNegativeIndex != -1) {
 533             firstNegative.resetAmount();
 534             moveItemLast(newList, singleNegativeIndex);
 535         }
 536         else if (singlePositiveIndex != -1) {
 537             firstPositive.resetAmount();
 538             moveItemLast(newList, singlePositiveIndex);
 539         }
 540
 541         Misc.onMainThread(() -> {
 542             setItems(newList);
 543             noteFocusChanged(1, FocusedElement.Amount);
 544         });
 545     }
 546     /**
 547      * A transaction is submittable if:
 548      * 0) has description
 549      * 1) has at least two account names
 550      * 2) each row with amount has account name
 551      * 3) for each commodity:
 552      * 3a) amounts must balance to 0, or
 553      * 3b) there must be exactly one empty amount (with account)
 554      * 4) empty accounts with empty amounts are ignored
 555      * Side effects:
 556      * 5) a row with an empty account name or empty amount is guaranteed to exist for each
 557      * commodity
 558      * 6) at least two rows need to be present in the ledger
 559      *
 560      * @param list - the item list to check. Can be the displayed list or a list that will be
 561      *             displayed soon
 562      */
 563     @SuppressLint("DefaultLocale")
 564     void checkTransactionSubmittable(@Nullable List<Item> list) {
 565         boolean workingWithLiveList = false;
 566         if (list == null) {
 567             list = copyList();
 568             workingWithLiveList = true;
 569         }
 570
 571         if (BuildConfig.DEBUG)
 572             dumpItemList(String.format("Before submittable checks (%s)",
 573                     workingWithLiveList ? "LIVE LIST" : "custom list"), list);
 574
 575         int accounts = 0;
 576         final BalanceForCurrency balance = new BalanceForCurrency();
 577         final String descriptionText = list.get(0)
 578                                            .toTransactionHead()
 579                                            .getDescription();
 580         boolean submittable = true;
 581         boolean listChanged = false;
 582         final ItemsForCurrency itemsForCurrency = new ItemsForCurrency();
 583         final ItemsForCurrency itemsWithEmptyAmountForCurrency = new ItemsForCurrency();
 584         final ItemsForCurrency itemsWithAccountAndEmptyAmountForCurrency = new ItemsForCurrency();
 585         final ItemsForCurrency itemsWithEmptyAccountForCurrency = new ItemsForCurrency();
 586         final ItemsForCurrency itemsWithAmountForCurrency = new ItemsForCurrency();
 587         final ItemsForCurrency itemsWithAccountForCurrency = new ItemsForCurrency();
 588         final ItemsForCurrency emptyRowsForCurrency = new ItemsForCurrency();
 589         final List<Item> emptyRows = new ArrayList<>();
 590
 591         try {
 592             if ((descriptionText == null) || descriptionText.trim()
 593                                                             .isEmpty())
 594             {
 595                 Logger.debug("submittable", "Transaction not submittable: missing description");
 596                 submittable = false;
 597             }
 598
 599             boolean hasInvalidAmount = false;
 600
 601             for (int i = 1; i < list.size(); i++) {
 602                 TransactionAccount item = list.get(i)
 603                                               .toTransactionAccount();
 604
 605                 String accName = item.getAccountName()
 606                                      .trim();
 607                 String currName = item.getCurrency();
 608
 609                 itemsForCurrency.add(currName, item);
 610
 611                 if (accName.isEmpty()) {
 612                     itemsWithEmptyAccountForCurrency.add(currName, item);
 613
 614                     if (item.isAmountSet()) {
 615                         // 2) each amount has account name
 616                         Logger.debug("submittable", String.format(
 617                                 "Transaction not submittable: row %d has no account name, but" +
 618                                 " has" + " amount %1.2f", i + 1, item.getAmount()));
 619                         submittable = false;
 620                     }
 621                     else {
 622                         emptyRowsForCurrency.add(currName, item);
 623                     }
 624                 }
 625                 else {
 626                     accounts++;
 627                     itemsWithAccountForCurrency.add(currName, item);
 628                 }
 629
 630                 if (item.isAmountSet() && item.isAmountValid()) {
 631                     itemsWithAmountForCurrency.add(currName, item);
 632                     balance.add(currName, item.getAmount());
 633                 }
 634                 else {
 635                     if (!item.isAmountValid()) {
 636                         Logger.debug("submittable",
 637                                 String.format("Not submittable: row %d has an invalid amount", i));
 638                         submittable = false;
 639                         hasInvalidAmount = true;
 640                     }
 641
 642                     itemsWithEmptyAmountForCurrency.add(currName, item);
 643
 644                     if (!accName.isEmpty())
 645                         itemsWithAccountAndEmptyAmountForCurrency.add(currName, item);
 646                 }
 647             }
 648
 649             // 1) has at least two account names
 650             if (accounts < 2) {
 651                 if (accounts == 0)
 652                     Logger.debug("submittable", "Transaction not submittable: no account names");
 653                 else if (accounts == 1)
 654                     Logger.debug("submittable",
 655                             "Transaction not submittable: only one account name");
 656                 else
 657                     Logger.debug("submittable",
 658                             String.format("Transaction not submittable: only %d account names",
 659                                     accounts));
 660                 submittable = false;
 661             }
 662
 663             // 3) for each commodity:
 664             // 3a) amount must balance to 0, or
 665             // 3b) there must be exactly one empty amount (with account)
 666             for (String balCurrency : itemsForCurrency.currencies()) {
 667                 float currencyBalance = balance.get(balCurrency);
 668                 if (Misc.isZero(currencyBalance)) {
 669                     // remove hints from all amount inputs in that currency
 670                     for (int i = 1; i < list.size(); i++) {
 671                         TransactionAccount acc = list.get(i)
 672                                                      .toTransactionAccount();
 673                         if (Misc.equalStrings(acc.getCurrency(), balCurrency)) {
 674                             if (BuildConfig.DEBUG)
 675                                 Logger.debug("submittable",
 676                                         String.format(Locale.US, "Resetting hint of %d:'%s' [%s]",
 677                                                 i, Misc.nullIsEmpty(acc.getAccountName()),
 678                                                 balCurrency));
 679                             // skip if the amount is set, in which case the hint is not
 680                             // important/visible
 681                             if (!acc.isAmountSet() && acc.amountHintIsSet &&
 682                                 !TextUtils.isEmpty(acc.getAmountHint()))
 683                             {
 684                                 acc.setAmountHint(null);
 685                                 listChanged = true;
 686                             }
 687                         }
 688                     }
 689                 }
 690                 else {
 691                     List<Item> tmpList =
 692                             itemsWithAccountAndEmptyAmountForCurrency.getList(balCurrency);
 693                     int balanceReceiversCount = tmpList.size();
 694                     if (balanceReceiversCount != 1) {
 695                         if (BuildConfig.DEBUG) {
 696                             if (balanceReceiversCount == 0)
 697                                 Logger.debug("submittable", String.format(
 698                                         "Transaction not submittable [curr:%s]: non-zero balance " +
 699                                         "with no empty amounts with accounts", balCurrency));
 700                             else
 701                                 Logger.debug("submittable", String.format(
 702                                         "Transaction not submittable [curr:%s]: non-zero balance " +
 703                                         "with multiple empty amounts with accounts", balCurrency));
 704                         }
 705                         submittable = false;
 706                     }
 707
 708                     List<Item> emptyAmountList =
 709                             itemsWithEmptyAmountForCurrency.getList(balCurrency);
 710
 711                     // suggest off-balance amount to a row and remove hints on other rows
 712                     Item receiver = null;
 713                     if (!tmpList.isEmpty())
 714                         receiver = tmpList.get(0);
 715                     else if (!emptyAmountList.isEmpty())
 716                         receiver = emptyAmountList.get(0);
 717
 718                     for (int i = 0; i < list.size(); i++) {
 719                         Item item = list.get(i);
 720                         if (!(item instanceof TransactionAccount))
 721                             continue;
 722
 723                         TransactionAccount acc = item.toTransactionAccount();
 724                         if (!Misc.equalStrings(acc.getCurrency(), balCurrency))
 725                             continue;
 726
 727                         if (item == receiver) {
 728                             final String hint = Data.formatNumber(-currencyBalance);
 729                             if (!acc.isAmountHintSet() ||
 730                                 !Misc.equalStrings(acc.getAmountHint(), hint))
 731                             {
 732                                 Logger.debug("submittable",
 733                                         String.format("Setting amount hint of {%s} to %s [%s]",
 734                                                 acc.toString(), hint, balCurrency));
 735                                 acc.setAmountHint(hint);
 736                                 listChanged = true;
 737                             }
 738                         }
 739                         else {
 740                             if (BuildConfig.DEBUG)
 741                                 Logger.debug("submittable",
 742                                         String.format("Resetting hint of '%s' [%s]",
 743                                                 Misc.nullIsEmpty(acc.getAccountName()),
 744                                                 balCurrency));
 745                             if (acc.amountHintIsSet && !TextUtils.isEmpty(acc.getAmountHint())) {
 746                                 acc.setAmountHint(null);
 747                                 listChanged = true;
 748                             }
 749                         }
 750                     }
 751                 }
 752             }
 753
 754             // 5) a row with an empty account name or empty amount is guaranteed to exist for
 755             // each commodity
 756             if (!hasInvalidAmount) {
 757                 for (String balCurrency : balance.currencies()) {
 758                     int currEmptyRows = itemsWithEmptyAccountForCurrency.size(balCurrency);
 759                     int currRows = itemsForCurrency.size(balCurrency);
 760                     int currAccounts = itemsWithAccountForCurrency.size(balCurrency);
 761                     int currAmounts = itemsWithAmountForCurrency.size(balCurrency);
 762                     if ((currEmptyRows == 0) &&
 763                         ((currRows == currAccounts) || (currRows == currAmounts)))
 764                     {
 765                         // perhaps there already is an unused empty row for another currency that
 766                         // is not used?
 767 //                        boolean foundIt = false;
 768 //                        for (Item item : emptyRows) {
 769 //                            Currency itemCurrency = item.getCurrency();
 770 //                            String itemCurrencyName =
 771 //                                    (itemCurrency == null) ? "" : itemCurrency.getName();
 772 //                            if (Misc.isZero(balance.get(itemCurrencyName))) {
 773 //                                item.setCurrency(Currency.loadByName(balCurrency));
 774 //                                item.setAmountHint(
 775 //                                        Data.formatNumber(-balance.get(balCurrency)));
 776 //                                foundIt = true;
 777 //                                break;
 778 //                            }
 779 //                        }
 780 //
 781 //                        if (!foundIt)
 782                         final TransactionAccount newAcc = new TransactionAccount("", balCurrency);
 783                         final float bal = balance.get(balCurrency);
 784                         if (!Misc.isZero(bal) && currAmounts == currRows)
 785                             newAcc.setAmountHint(Data.formatNumber(-bal));
 786                         Logger.debug("submittable",
 787                                 String.format("Adding new item with %s for currency %s",
 788                                         newAcc.getAmountHint(), balCurrency));
 789                         list.add(newAcc);
 790                         listChanged = true;
 791                     }
 792                 }
 793             }
 794
 795             // drop extra empty rows, not needed
 796             for (String currName : emptyRowsForCurrency.currencies()) {
 797                 List<Item> emptyItems = emptyRowsForCurrency.getList(currName);
 798                 while ((list.size() > MIN_ITEMS) && (emptyItems.size() > 1)) {
 799                     // the list is a copy, so the empty item is no longer present
 800                     Item itemToRemove = emptyItems.remove(1);
 801                     removeItemById(list, itemToRemove.id);
 802                     listChanged = true;
 803                 }
 804
 805                 // unused currency, remove last item (which is also an empty one)
 806                 if ((list.size() > MIN_ITEMS) && (emptyItems.size() == 1)) {
 807                     List<Item> currItems = itemsForCurrency.getList(currName);
 808
 809                     if (currItems.size() == 1) {
 810                         // the list is a copy, so the empty item is no longer present
 811                         removeItemById(list, emptyItems.get(0).id);
 812                         listChanged = true;
 813                     }
 814                 }
 815             }
 816
 817             // 6) at least two rows need to be present in the ledger
 818             //    (the list also contains header and trailer)
 819             while (list.size() < MIN_ITEMS) {
 820                 list.add(new TransactionAccount(""));
 821                 listChanged = true;
 822             }
 823
 824             Logger.debug("submittable", submittable ? "YES" : "NO");
 825             isSubmittable.setValue(submittable);
 826
 827             if (BuildConfig.DEBUG)
 828                 dumpItemList("After submittable checks", list);
 829         }
 830         catch (NumberFormatException e) {
 831             Logger.debug("submittable", "NO (because of NumberFormatException)");
 832             isSubmittable.setValue(false);
 833         }
 834         catch (Exception e) {
 835             e.printStackTrace();
 836             Logger.debug("submittable", "NO (because of an Exception)");
 837             isSubmittable.setValue(false);
 838         }
 839
 840         if (listChanged && workingWithLiveList) {
 841             setItemsWithoutSubmittableChecks(list);
 842         }
 843     }
 844     private void removeItemById(@NotNull List<Item> list, int id) {
 845         if (android.os.Build.VERSION.SDK_INT >= android.os.Build.VERSION_CODES.N) {
 846             list.removeIf(item -> item.id == id);
 847         }
 848         else {
 849             for (Item item : list) {
 850                 if (item.id == id) {
 851                     list.remove(item);
 852                     break;
 853                 }
 854             }
 855         }
 856     }
 857     @SuppressLint("DefaultLocale")
 858     private void dumpItemList(@NotNull String msg, @NotNull List<Item> list) {
 859         Logger.debug("submittable", "== Dump of all items " + msg);
 860         for (int i = 1; i < list.size(); i++) {
 861             TransactionAccount item = list.get(i)
 862                                           .toTransactionAccount();
 863             Logger.debug("submittable", String.format("%d:%s", i, item.toString()));
 864         }
 865     }
 866     public void setItemCurrency(int position, String newCurrency) {
 867         TransactionAccount item = Objects.requireNonNull(items.getValue())
 868                                          .get(position)
 869                                          .toTransactionAccount();
 870         final String oldCurrency = item.getCurrency();
 871
 872         if (Misc.equalStrings(oldCurrency, newCurrency))
 873             return;
 874
 875         List<Item> newList = copyList();
 876         newList.get(position)
 877                .toTransactionAccount()
 878                .setCurrency(newCurrency);
 879
 880         setItems(newList);
 881     }
 882     public boolean accountListIsEmpty() {
 883         List<Item> items = Objects.requireNonNull(this.items.getValue());
 884
 885         for (Item item : items) {
 886             if (!(item instanceof TransactionAccount))
 887                 continue;
 888
 889             if (!((TransactionAccount) item).isEmpty())
 890                 return false;
 891         }
 892
 893         return true;
 894     }
 895
 896     public static class FocusInfo {
 897         int position;
 898         FocusedElement element;
 899         public FocusInfo(int position, @Nullable FocusedElement element) {
 900             this.position = position;
 901             this.element = element;
 902         }
 903     }
 904
 905     static abstract class Item {
 906         private static int idDispenser = 0;
 907         protected int id;
 908         private Item() {
 909             if (this instanceof TransactionHead)
 910                 id = 0;
 911             else
 912                 synchronized (Item.class) {
 913                     id = ++idDispenser;
 914                 }
 915         }
 916         public Item(int id) {
 917             this.id = id;
 918         }
 919         public static Item from(Item origin) {
 920             if (origin instanceof TransactionHead)
 921                 return new TransactionHead((TransactionHead) origin);
 922             if (origin instanceof TransactionAccount)
 923                 return new TransactionAccount((TransactionAccount) origin);
 924             throw new RuntimeException("Don't know how to handle " + origin);
 925         }
 926         private static void resetIdDispenser() {
 927             idDispenser = 0;
 928         }
 929         public int getId() {
 930             return id;
 931         }
 932         public abstract ItemType getType();
 933         public TransactionHead toTransactionHead() {
 934             if (this instanceof TransactionHead)
 935                 return (TransactionHead) this;
 936
 937             throw new IllegalStateException("Wrong item type " + this);
 938         }
 939         public TransactionAccount toTransactionAccount() {
 940             if (this instanceof TransactionAccount)
 941                 return (TransactionAccount) this;
 942
 943             throw new IllegalStateException("Wrong item type " + this);
 944         }
 945         public boolean equalContents(@Nullable Object item) {
 946             if (item == null)
 947                 return false;
 948
 949             if (!getClass().equals(item.getClass()))
 950                 return false;
 951
 952             // shortcut - comparing same instance
 953             if (item == this)
 954                 return true;
 955
 956             if (this instanceof TransactionHead)
 957                 return ((TransactionHead) item).equalContents((TransactionHead) this);
 958             if (this instanceof TransactionAccount)
 959                 return ((TransactionAccount) item).equalContents((TransactionAccount) this);
 960
 961             throw new RuntimeException("Don't know how to handle " + this);
 962         }
 963     }
 964
 965
 966 //==========================================================================================
 967
 968     public static class TransactionHead extends Item {
 969         private SimpleDate date;
 970         private String description;
 971         private String comment;
 972         TransactionHead(String description) {
 973             super();
 974             this.description = description;
 975         }
 976         public TransactionHead(TransactionHead origin) {
 977             super(origin.id);
 978             date = origin.date;
 979             description = origin.description;
 980             comment = origin.comment;
 981         }
 982         public SimpleDate getDate() {
 983             return date;
 984         }
 985         public void setDate(SimpleDate date) {
 986             this.date = date;
 987         }
 988         public void setDate(String text) throws ParseException {
 989             if (Misc.emptyIsNull(text) == null) {
 990                 date = null;
 991                 return;
 992             }
 993
 994             date = Globals.parseLedgerDate(text);
 995         }
 996         /**
 997          * getFormattedDate()
 998          *
 999          * @return nicely formatted, shortest available date representation
1000          */
1001         String getFormattedDate() {
1002             if (date == null)
1003                 return null;
1004
1005             Calendar today = GregorianCalendar.getInstance();
1006
1007             if (today.get(Calendar.YEAR) != date.year) {
1008                 return String.format(Locale.US, "%d/%02d/%02d", date.year, date.month, date.day);
1009             }
1010
1011             if (today.get(Calendar.MONTH) + 1 != date.month) {
1012                 return String.format(Locale.US, "%d/%02d", date.month, date.day);
1013             }
1014
1015             return String.valueOf(date.day);
1016         }
1017         @NonNull
1018         @Override
1019         public String toString() {
1020             @SuppressLint("DefaultLocale") StringBuilder b = new StringBuilder(
1021                     String.format("id:%d/%s", id, Integer.toHexString(hashCode())));
1022
1023             if (TextUtils.isEmpty(description))
1024                 b.append(" «no description»");
1025             else
1026                 b.append(String.format(" '%s'", description));
1027
1028             if (date != null)
1029                 b.append(String.format("@%s", date.toString()));
1030
1031             if (!TextUtils.isEmpty(comment))
1032                 b.append(String.format(" /%s/", comment));
1033
1034             return b.toString();
1035         }
1036         public String getDescription() {
1037             return description;
1038         }
1039         public void setDescription(String description) {
1040             this.description = description;
1041         }
1042         public String getComment() {
1043             return comment;
1044         }
1045         public void setComment(String comment) {
1046             this.comment = comment;
1047         }
1048         @Override
1049         public ItemType getType() {
1050             return ItemType.generalData;
1051         }
1052         public LedgerTransaction asLedgerTransaction() {
1053             return new LedgerTransaction(0, (date == null) ? SimpleDate.today() : date, description,
1054                     Objects.requireNonNull(Data.getProfile()));
1055         }
1056         public boolean equalContents(TransactionHead other) {
1057             if (other == null)
1058                 return false;
1059
1060             return Objects.equals(date, other.date) &&
1061                    Misc.equalStrings(description, other.description) &&
1062                    Misc.equalStrings(comment, other.comment);
1063         }
1064     }
1065
1066     public static class TransactionAccount extends Item {
1067         private String accountName;
1068         private String amountHint;
1069         private String comment;
1070         @NotNull
1071         private String currency = "";
1072         private float amount;
1073         private boolean amountSet;
1074         private boolean amountValid = true;
1075         @NotNull
1076         private String amountText = "";
1077         private FocusedElement focusedElement = FocusedElement.Account;
1078         private boolean amountHintIsSet = false;
1079         private boolean isLast = false;
1080         private int accountNameCursorPosition;
1081         public TransactionAccount(TransactionAccount origin) {
1082             super(origin.id);
1083             accountName = origin.accountName;
1084             amount = origin.amount;
1085             amountSet = origin.amountSet;
1086             amountHint = origin.amountHint;
1087             amountHintIsSet = origin.amountHintIsSet;
1088             amountText = origin.amountText;
1089             comment = origin.comment;
1090             currency = origin.currency;
1091             amountValid = origin.amountValid;
1092             focusedElement = origin.focusedElement;
1093             isLast = origin.isLast;
1094             accountNameCursorPosition = origin.accountNameCursorPosition;
1095         }
1096         public TransactionAccount(String accountName) {
1097             super();
1098             this.accountName = accountName;
1099         }
1100         public TransactionAccount(String accountName, @NotNull String currency) {
1101             super();
1102             this.accountName = accountName;
1103             this.currency = currency;
1104         }
1105         public @NotNull String getAmountText() {
1106             return amountText;
1107         }
1108         public void setAmountText(@NotNull String amountText) {
1109             this.amountText = amountText;
1110         }
1111         public boolean setAndCheckAmountText(@NotNull String amountText) {
1112             String amtText = amountText.trim();
1113             this.amountText = amtText;
1114
1115             boolean significantChange = false;
1116
1117             if (amtText.isEmpty()) {
1118                 if (amountSet) {
1119                     significantChange = true;
1120                 }
1121                 resetAmount();
1122             }
1123             else {
1124                 try {
1125                     amtText = amtText.replace(Data.getDecimalSeparator(), Data.decimalDot);
1126                     final float parsedAmount = Float.parseFloat(amtText);
1127                     if (!amountSet || !amountValid || !Misc.equalFloats(parsedAmount, amount))
1128                         significantChange = true;
1129                     amount = parsedAmount;
1130                     amountSet = true;
1131                     amountValid = true;
1132                 }
1133                 catch (NumberFormatException e) {
1134                     Logger.debug("new-trans", String.format(
1135                             "assuming amount is not set due to number format exception. " +
1136                             "input was '%s'", amtText));
1137                     if (amountValid) // it was valid and now it's not
1138                         significantChange = true;
1139                     amountValid = false;
1140                 }
1141             }
1142
1143             return significantChange;
1144         }
1145         public boolean isLast() {
1146             return isLast;
1147         }
1148         public boolean isAmountSet() {
1149             return amountSet;
1150         }
1151         public String getAccountName() {
1152             return accountName;
1153         }
1154         public void setAccountName(String accountName) {
1155             this.accountName = accountName;
1156         }
1157         public float getAmount() {
1158             if (!amountSet)
1159                 throw new IllegalStateException("Amount is not set");
1160             return amount;
1161         }
1162         public void setAmount(float amount) {
1163             this.amount = amount;
1164             amountSet = true;
1165             amountValid = true;
1166             amountText = Data.formatNumber(amount);
1167         }
1168         public void resetAmount() {
1169             amountSet = false;
1170             amountValid = true;
1171             amountText = "";
1172         }
1173         @Override
1174         public ItemType getType() {
1175             return ItemType.transactionRow;
1176         }
1177         public String getAmountHint() {
1178             return amountHint;
1179         }
1180         public void setAmountHint(String amountHint) {
1181             this.amountHint = amountHint;
1182             amountHintIsSet = !TextUtils.isEmpty(amountHint);
1183         }
1184         public String getComment() {
1185             return comment;
1186         }
1187         public void setComment(String comment) {
1188             this.comment = comment;
1189         }
1190         @NotNull
1191         public String getCurrency() {
1192             return currency;
1193         }
1194         public void setCurrency(@org.jetbrains.annotations.Nullable String currency) {
1195             this.currency = Misc.nullIsEmpty(currency);
1196         }
1197         public boolean isAmountValid() {
1198             return amountValid;
1199         }
1200         public void setAmountValid(boolean amountValid) {
1201             this.amountValid = amountValid;
1202         }
1203         public FocusedElement getFocusedElement() {
1204             return focusedElement;
1205         }
1206         public void setFocusedElement(FocusedElement focusedElement) {
1207             this.focusedElement = focusedElement;
1208         }
1209         public boolean isAmountHintSet() {
1210             return amountHintIsSet;
1211         }
1212         public void setAmountHintIsSet(boolean amountHintIsSet) {
1213             this.amountHintIsSet = amountHintIsSet;
1214         }
1215         public boolean isEmpty() {
1216             return !amountSet && Misc.emptyIsNull(accountName) == null &&
1217                    Misc.emptyIsNull(comment) == null;
1218         }
1219         @SuppressLint("DefaultLocale")
1220         @Override
1221         @NotNull
1222         public String toString() {
1223             StringBuilder b = new StringBuilder();
1224             b.append(String.format("id:%d/%s", id, Integer.toHexString(hashCode())));
1225             if (!TextUtils.isEmpty(accountName))
1226                 b.append(String.format(" acc'%s'", accountName));
1227
1228             if (amountSet)
1229                 b.append(amountText)
1230                  .append(" [")
1231                  .append(amountValid ? "valid" : "invalid")
1232                  .append("] ")
1233                  .append(String.format(Locale.ROOT, " {raw %4.2f}", amount));
1234             else if (amountHintIsSet)
1235                 b.append(String.format(" (hint %s)", amountHint));
1236
1237             if (!TextUtils.isEmpty(currency))
1238                 b.append(" ")
1239                  .append(currency);
1240
1241             if (!TextUtils.isEmpty(comment))
1242                 b.append(String.format(" /%s/", comment));
1243
1244             if (isLast)
1245                 b.append(" last");
1246
1247             return b.toString();
1248         }
1249         public boolean equalContents(TransactionAccount other) {
1250             if (other == null)
1251                 return false;
1252
1253             boolean equal = Misc.equalStrings(accountName, other.accountName);
1254             equal = equal && Misc.equalStrings(comment, other.comment) &&
1255                     (amountSet ? other.amountSet && amountValid == other.amountValid &&
1256                                  Misc.equalStrings(amountText, other.amountText)
1257                                : !other.amountSet);
1258
1259             // compare amount hint only if there is no amount
1260             if (!amountSet)
1261                 equal = equal && (amountHintIsSet ? other.amountHintIsSet &&
1262                                                     Misc.equalStrings(amountHint, other.amountHint)
1263                                                   : !other.amountHintIsSet);
1264             equal = equal && Misc.equalStrings(currency, other.currency) && isLast == other.isLast;
1265
1266             Logger.debug("new-trans",
1267                     String.format("Comparing {%s} and {%s}: %s", this.toString(), other.toString(),
1268                             equal));
1269             return equal;
1270         }
1271         public int getAccountNameCursorPosition() {
1272             return accountNameCursorPosition;
1273         }
1274         public void setAccountNameCursorPosition(int position) {
1275             this.accountNameCursorPosition = position;
1276         }
1277     }
1278
1279     private static class BalanceForCurrency {
1280         private final HashMap<String, Float> hashMap = new HashMap<>();
1281         float get(String currencyName) {
1282             Float f = hashMap.get(currencyName);
1283             if (f == null) {
1284                 f = 0f;
1285                 hashMap.put(currencyName, f);
1286             }
1287             return f;
1288         }
1289         void add(String currencyName, float amount) {
1290             hashMap.put(currencyName, get(currencyName) + amount);
1291         }
1292         Set<String> currencies() {
1293             return hashMap.keySet();
1294         }
1295         boolean containsCurrency(String currencyName) {
1296             return hashMap.containsKey(currencyName);
1297         }
1298     }
1299
1300     private static class ItemsForCurrency {
1301         private final HashMap<@NotNull String, List<Item>> hashMap = new HashMap<>();
1302         @NonNull
1303         List<NewTransactionModel.Item> getList(@NotNull String currencyName) {
1304             List<NewTransactionModel.Item> list = hashMap.get(currencyName);
1305             if (list == null) {
1306                 list = new ArrayList<>();
1307                 hashMap.put(currencyName, list);
1308             }
1309             return list;
1310         }
1311         void add(@NotNull String currencyName, @NonNull NewTransactionModel.Item item) {
1312             getList(Objects.requireNonNull(currencyName)).add(item);
1313         }
1314         int size(@NotNull String currencyName) {
1315             return this.getList(Objects.requireNonNull(currencyName))
1316                        .size();
1317         }
1318         Set<String> currencies() {
1319             return hashMap.keySet();
1320         }
1321     }
1322 }