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