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