library/BasicLibrary.java

   1 package be.nikiroo.fanfix.library;
   2
   3 import java.io.File;
   4 import java.io.IOException;
   5 import java.net.URL;
   6 import java.net.UnknownHostException;
   7 import java.util.ArrayList;
   8 import java.util.Collections;
   9 import java.util.List;
  10 import java.util.Map;
  11 import java.util.TreeMap;
  12
  13 import be.nikiroo.fanfix.Instance;
  14 import be.nikiroo.fanfix.data.MetaData;
  15 import be.nikiroo.fanfix.data.Story;
  16 import be.nikiroo.fanfix.output.BasicOutput;
  17 import be.nikiroo.fanfix.output.BasicOutput.OutputType;
  18 import be.nikiroo.fanfix.supported.BasicSupport;
  19 import be.nikiroo.fanfix.supported.SupportType;
  20 import be.nikiroo.utils.Image;
  21 import be.nikiroo.utils.Progress;
  22 import be.nikiroo.utils.StringUtils;
  23
  24 /**
  25  * Manage a library of Stories: import, export, list, modify.
  26  * <p>
  27  * Each {@link Story} object will be associated with a (local to the library)
  28  * unique ID, the LUID, which will be used to identify the {@link Story}.
  29  * <p>
  30  * Most of the {@link BasicLibrary} functions work on a partial (cover
  31  * <b>MAY</b> not be included) {@link MetaData} object.
  32  *
  33  * @author niki
  34  */
  35 abstract public class BasicLibrary {
  36         /**
  37          * A {@link BasicLibrary} status.
  38          *
  39          * @author niki
  40          */
  41         public enum Status {
  42                 /** The library is ready and r/w. */
  43                 READ_WRITE,
  44                 /** The library is ready, but read-only. */
  45                 READ_ONLY,
  46                 /** The library is invalid (not correctly set up). */
  47                 INVALID,
  48                 /** You are not allowed to access this library. */
  49                 UNAUTHORIZED,
  50                 /** The library is currently out of commission. */
  51                 UNAVAILABLE;
  52
  53                 /**
  54                  * The library is available (you can query it).
  55                  * <p>
  56                  * It does <b>not</b> specify if it is read-only or not.
  57                  *
  58                  * @return TRUE if it is
  59                  */
  60                 public boolean isReady() {
  61                         return (this == READ_WRITE || this == READ_ONLY);
  62                 }
  63
  64                 /**
  65                  * This library can be modified (= you are allowed to modify it).
  66                  *
  67                  * @return TRUE if it is
  68                  */
  69                 public boolean isWritable() {
  70                         return (this == READ_WRITE);
  71                 }
  72         }
  73
  74         /**
  75          * Return a name for this library (the UI may display this).
  76          * <p>
  77          * Must not be NULL.
  78          *
  79          * @return the name, or an empty {@link String} if none
  80          */
  81         public String getLibraryName() {
  82                 return "";
  83         }
  84
  85         /**
  86          * The library status.
  87          *
  88          * @return the current status
  89          */
  90         public Status getStatus() {
  91                 return Status.READ_WRITE;
  92         }
  93
  94         /**
  95          * Retrieve the main {@link File} corresponding to the given {@link Story},
  96          * which can be passed to an external reader or instance.
  97          * <p>
  98          * Do <b>NOT</b> alter this file.
  99          *
 100          * @param luid
 101          *            the Library UID of the story
 102          * @param pg
 103          *            the optional {@link Progress}
 104          *
 105          * @return the corresponding {@link Story}
 106          *
 107          * @throws IOException
 108          *             in case of IOException
 109          */
 110         public abstract File getFile(String luid, Progress pg) throws IOException;
 111
 112         /**
 113          * Return the cover image associated to this story.
 114          *
 115          * @param luid
 116          *            the Library UID of the story
 117          *
 118          * @return the cover image
 119          *
 120          * @throws IOException
 121          *             in case of IOException
 122          */
 123         public abstract Image getCover(String luid) throws IOException;
 124
 125         // TODO: ensure it is the main used interface
 126         public synchronized MetaResultList getList(Progress pg) throws IOException {
 127                 return new MetaResultList(getMetas(pg));
 128         }
 129
 130         //TODO: make something for (normal and custom) not-story covers
 131
 132         /**
 133          * Return the cover image associated to this source.
 134          * <p>
 135          * By default, return the custom cover if any, and if not, return the cover
 136          * of the first story with this source.
 137          *
 138          * @param source
 139          *            the source
 140          *
 141          * @return the cover image or NULL
 142          *
 143          * @throws IOException
 144          *             in case of IOException
 145          */
 146         public Image getSourceCover(String source) throws IOException {
 147                 Image custom = getCustomSourceCover(source);
 148                 if (custom != null) {
 149                         return custom;
 150                 }
 151
 152                 List<MetaData> metas = getList().filter(source, null, null);
 153                 if (metas.size() > 0) {
 154                         return getCover(metas.get(0).getLuid());
 155                 }
 156
 157                 return null;
 158         }
 159
 160         /**
 161          * Return the cover image associated to this author.
 162          * <p>
 163          * By default, return the custom cover if any, and if not, return the cover
 164          * of the first story with this author.
 165          *
 166          * @param author
 167          *            the author
 168          *
 169          * @return the cover image or NULL
 170          *
 171          * @throws IOException
 172          *             in case of IOException
 173          */
 174         public Image getAuthorCover(String author) throws IOException {
 175                 Image custom = getCustomAuthorCover(author);
 176                 if (custom != null) {
 177                         return custom;
 178                 }
 179
 180                 List<MetaData> metas = getList().filter(null, author, null);
 181                 if (metas.size() > 0) {
 182                         return getCover(metas.get(0).getLuid());
 183                 }
 184
 185                 return null;
 186         }
 187
 188         /**
 189          * Return the custom cover image associated to this source.
 190          * <p>
 191          * By default, return NULL.
 192          *
 193          * @param source
 194          *            the source to look for
 195          *
 196          * @return the custom cover or NULL if none
 197          *
 198          * @throws IOException
 199          *             in case of IOException
 200          */
 201         @SuppressWarnings("unused")
 202         public Image getCustomSourceCover(String source) throws IOException {
 203                 return null;
 204         }
 205
 206         /**
 207          * Return the custom cover image associated to this author.
 208          * <p>
 209          * By default, return NULL.
 210          *
 211          * @param author
 212          *            the author to look for
 213          *
 214          * @return the custom cover or NULL if none
 215          *
 216          * @throws IOException
 217          *             in case of IOException
 218          */
 219         @SuppressWarnings("unused")
 220         public Image getCustomAuthorCover(String author) throws IOException {
 221                 return null;
 222         }
 223
 224         /**
 225          * Set the source cover to the given story cover.
 226          *
 227          * @param source
 228          *            the source to change
 229          * @param luid
 230          *            the story LUID
 231          *
 232          * @throws IOException
 233          *             in case of IOException
 234          */
 235         public abstract void setSourceCover(String source, String luid)
 236                         throws IOException;
 237
 238         /**
 239          * Set the author cover to the given story cover.
 240          *
 241          * @param author
 242          *            the author to change
 243          * @param luid
 244          *            the story LUID
 245          *
 246          * @throws IOException
 247          *             in case of IOException
 248          */
 249         public abstract void setAuthorCover(String author, String luid)
 250                         throws IOException;
 251
 252         /**
 253          * Return the list of stories (represented by their {@link MetaData}, which
 254          * <b>MAY</b> not have the cover included).
 255          * <p>
 256          * The returned list <b>MUST</b> be a copy, not the original one.
 257          *
 258          * @param pg
 259          *            the optional {@link Progress}
 260          *
 261          * @return the list (can be empty but not NULL)
 262          *
 263          * @throws IOException
 264          *             in case of IOException
 265          */
 266         protected abstract List<MetaData> getMetas(Progress pg) throws IOException;
 267
 268         /**
 269          * Invalidate the {@link Story} cache (when the content should be re-read
 270          * because it was changed).
 271          */
 272         protected void invalidateInfo() {
 273                 invalidateInfo(null);
 274         }
 275
 276         /**
 277          * Invalidate the {@link Story} cache (when the content is removed).
 278          * <p>
 279          * All the cache can be deleted if NULL is passed as meta.
 280          *
 281          * @param luid
 282          *            the LUID of the {@link Story} to clear from the cache, or NULL
 283          *            for all stories
 284          */
 285         protected abstract void invalidateInfo(String luid);
 286
 287         /**
 288          * Invalidate the {@link Story} cache (when the content has changed, but we
 289          * already have it) with the new given meta.
 290          *
 291          * @param meta
 292          *            the {@link Story} to clear from the cache
 293          *
 294          * @throws IOException
 295          *             in case of IOException
 296          */
 297         protected abstract void updateInfo(MetaData meta) throws IOException;
 298
 299         /**
 300          * Return the next LUID that can be used.
 301          *
 302          * @return the next luid
 303          */
 304         protected abstract int getNextId();
 305
 306         /**
 307          * Delete the target {@link Story}.
 308          *
 309          * @param luid
 310          *            the LUID of the {@link Story}
 311          *
 312          * @throws IOException
 313          *             in case of I/O error or if the {@link Story} wa not found
 314          */
 315         protected abstract void doDelete(String luid) throws IOException;
 316
 317         /**
 318          * Actually save the story to the back-end.
 319          *
 320          * @param story
 321          *            the {@link Story} to save
 322          * @param pg
 323          *            the optional {@link Progress}
 324          *
 325          * @return the saved {@link Story} (which may have changed, especially
 326          *         regarding the {@link MetaData})
 327          *
 328          * @throws IOException
 329          *             in case of I/O error
 330          */
 331         protected abstract Story doSave(Story story, Progress pg)
 332                         throws IOException;
 333
 334         /**
 335          * Refresh the {@link BasicLibrary}, that is, make sure all metas are
 336          * loaded.
 337          *
 338          * @param pg
 339          *            the optional progress reporter
 340          */
 341         public synchronized void refresh(Progress pg) {
 342                 try {
 343                         getMetas(pg);
 344                 } catch (IOException e) {
 345                         // We will let it fail later
 346                 }
 347         }
 348
 349         /**
 350          * Check if the {@link Story} denoted by this Library UID is present in the
 351          * cache (if we have no cache, we default to </t>true</tt>).
 352          *
 353          * @param luid
 354          *            the Library UID
 355          *
 356          * @return TRUE if it is
 357          */
 358         public boolean isCached(String luid) {
 359                 // By default, everything is cached
 360                 return true;
 361         }
 362
 363         /**
 364          * Clear the {@link Story} from the cache, if needed.
 365          * <p>
 366          * The next time we try to retrieve the {@link Story}, it may be required to
 367          * cache it again.
 368          *
 369          * @param luid
 370          *            the story to clear
 371          *
 372          * @throws IOException
 373          *             in case of I/O error
 374          */
 375         public void clearFromCache(String luid) throws IOException {
 376                 // By default, this is a noop.
 377         }
 378
 379         /**
 380          * List all the known types (sources) of stories.
 381          *
 382          * @return the sources
 383          *
 384          * @throws IOException
 385          *             in case of IOException
 386          */
 387         public synchronized List<String> getSources() throws IOException {
 388                 List<String> list = new ArrayList<String>();
 389                 for (MetaData meta : getMetas(null)) {
 390                         String storySource = meta.getSource();
 391                         if (!list.contains(storySource)) {
 392                                 list.add(storySource);
 393                         }
 394                 }
 395
 396                 Collections.sort(list);
 397                 return list;
 398         }
 399
 400         /**
 401          * List all the known types (sources) of stories, grouped by directory
 402          * ("Source_1/a" and "Source_1/b" will be grouped into "Source_1").
 403          * <p>
 404          * Note that an empty item in the list means a non-grouped source (type) --
 405          * e.g., you could have for Source_1:
 406          * <ul>
 407          * <li><tt></tt>: empty, so source is "Source_1"</li>
 408          * <li><tt>a</tt>: empty, so source is "Source_1/a"</li>
 409          * <li><tt>b</tt>: empty, so source is "Source_1/b"</li>
 410          * </ul>
 411          *
 412          * @return the grouped list
 413          *
 414          * @throws IOException
 415          *             in case of IOException
 416          */
 417         public synchronized Map<String, List<String>> getSourcesGrouped()
 418                         throws IOException {
 419                 Map<String, List<String>> map = new TreeMap<String, List<String>>();
 420                 for (String source : getSources()) {
 421                         String name;
 422                         String subname;
 423
 424                         int pos = source.indexOf('/');
 425                         if (pos > 0 && pos < source.length() - 1) {
 426                                 name = source.substring(0, pos);
 427                                 subname = source.substring(pos + 1);
 428
 429                         } else {
 430                                 name = source;
 431                                 subname = "";
 432                         }
 433
 434                         List<String> list = map.get(name);
 435                         if (list == null) {
 436                                 list = new ArrayList<String>();
 437                                 map.put(name, list);
 438                         }
 439                         list.add(subname);
 440                 }
 441
 442                 return map;
 443         }
 444
 445         /**
 446          * List all the known authors of stories.
 447          *
 448          * @return the authors
 449          *
 450          * @throws IOException
 451          *             in case of IOException
 452          */
 453         public synchronized List<String> getAuthors() throws IOException {
 454                 List<String> list = new ArrayList<String>();
 455                 for (MetaData meta : getMetas(null)) {
 456                         String storyAuthor = meta.getAuthor();
 457                         if (!list.contains(storyAuthor)) {
 458                                 list.add(storyAuthor);
 459                         }
 460                 }
 461
 462                 Collections.sort(list);
 463                 return list;
 464         }
 465
 466         /**
 467          * Return the list of authors, grouped by starting letter(s) if needed.
 468          * <p>
 469          * If the number of author is not too high, only one group with an empty
 470          * name and all the authors will be returned.
 471          * <p>
 472          * If not, the authors will be separated into groups:
 473          * <ul>
 474          * <li><tt>*</tt>: any author whose name doesn't contain letters nor numbers
 475          * </li>
 476          * <li><tt>0-9</tt>: any authors whose name starts with a number</li>
 477          * <li><tt>A-C</tt> (for instance): any author whose name starts with
 478          * <tt>A</tt>, <tt>B</tt> or <tt>C</tt></li>
 479          * </ul>
 480          * Note that the letters used in the groups can vary (except <tt>*</tt> and
 481          * <tt>0-9</tt>, which may only be present or not).
 482          *
 483          * @return the authors' names, grouped by letter(s)
 484          *
 485          * @throws IOException
 486          *             in case of IOException
 487          */
 488         public Map<String, List<String>> getAuthorsGrouped() throws IOException {
 489                 int MAX = 20;
 490
 491                 Map<String, List<String>> groups = new TreeMap<String, List<String>>();
 492                 List<String> authors = getAuthors();
 493
 494                 // If all authors fit the max, just report them as is
 495                 if (authors.size() <= MAX) {
 496                         groups.put("", authors);
 497                         return groups;
 498                 }
 499
 500                 // Create groups A to Z, which can be empty here
 501                 for (char car = 'A'; car <= 'Z'; car++) {
 502                         groups.put(Character.toString(car), getAuthorsGroup(authors, car));
 503                 }
 504
 505                 // Collapse them
 506                 List<String> keys = new ArrayList<String>(groups.keySet());
 507                 for (int i = 0; i + 1 < keys.size(); i++) {
 508                         String keyNow = keys.get(i);
 509                         String keyNext = keys.get(i + 1);
 510
 511                         List<String> now = groups.get(keyNow);
 512                         List<String> next = groups.get(keyNext);
 513
 514                         int currentTotal = now.size() + next.size();
 515                         if (currentTotal <= MAX) {
 516                                 String key = keyNow.charAt(0) + "-"
 517                                                 + keyNext.charAt(keyNext.length() - 1);
 518
 519                                 List<String> all = new ArrayList<String>();
 520                                 all.addAll(now);
 521                                 all.addAll(next);
 522
 523                                 groups.remove(keyNow);
 524                                 groups.remove(keyNext);
 525                                 groups.put(key, all);
 526
 527                                 keys.set(i, key); // set the new key instead of key(i)
 528                                 keys.remove(i + 1); // remove the next, consumed key
 529                                 i--; // restart at key(i)
 530                         }
 531                 }
 532
 533                 // Add "special" groups
 534                 groups.put("*", getAuthorsGroup(authors, '*'));
 535                 groups.put("0-9", getAuthorsGroup(authors, '0'));
 536
 537                 // Prune empty groups
 538                 keys = new ArrayList<String>(groups.keySet());
 539                 for (String key : keys) {
 540                         if (groups.get(key).isEmpty()) {
 541                                 groups.remove(key);
 542                         }
 543                 }
 544
 545                 return groups;
 546         }
 547
 548         /**
 549          * Get all the authors that start with the given character:
 550          * <ul>
 551          * <li><tt>*</tt>: any author whose name doesn't contain letters nor numbers
 552          * </li>
 553          * <li><tt>0</tt>: any authors whose name starts with a number</li>
 554          * <li><tt>A</tt> (any capital latin letter): any author whose name starts
 555          * with <tt>A</tt></li>
 556          * </ul>
 557          *
 558          * @param authors
 559          *            the full list of authors
 560          * @param car
 561          *            the starting character, <tt>*</tt>, <tt>0</tt> or a capital
 562          *            letter
 563          *
 564          * @return the authors that fulfil the starting letter
 565          */
 566         private List<String> getAuthorsGroup(List<String> authors, char car) {
 567                 List<String> accepted = new ArrayList<String>();
 568                 for (String author : authors) {
 569                         char first = '*';
 570                         for (int i = 0; first == '*' && i < author.length(); i++) {
 571                                 String san = StringUtils.sanitize(author, true, true);
 572                                 char c = san.charAt(i);
 573                                 if (c >= '0' && c <= '9') {
 574                                         first = '0';
 575                                 } else if (c >= 'a' && c <= 'z') {
 576                                         first = (char) (c - 'a' + 'A');
 577                                 } else if (c >= 'A' && c <= 'Z') {
 578                                         first = c;
 579                                 }
 580                         }
 581
 582                         if (first == car) {
 583                                 accepted.add(author);
 584                         }
 585                 }
 586
 587                 return accepted;
 588         }
 589
 590         /**
 591          * List all the stories in the {@link BasicLibrary}.
 592          * <p>
 593          * Cover images <b>MAYBE</b> not included.
 594          *
 595          * @return the stories
 596          *
 597          * @throws IOException
 598          *             in case of IOException
 599          */
 600         public MetaResultList getList() throws IOException {
 601                 return getList(null);
 602         }
 603
 604         /**
 605          * Retrieve a {@link MetaData} corresponding to the given {@link Story},
 606          * cover image <b>MAY</b> not be included.
 607          *
 608          * @param luid
 609          *            the Library UID of the story
 610          *
 611          * @return the corresponding {@link Story}
 612          *
 613          * @throws IOException
 614          *             in case of IOException
 615          */
 616         public synchronized MetaData getInfo(String luid) throws IOException {
 617                 if (luid != null) {
 618                         for (MetaData meta : getMetas(null)) {
 619                                 if (luid.equals(meta.getLuid())) {
 620                                         return meta;
 621                                 }
 622                         }
 623                 }
 624
 625                 return null;
 626         }
 627
 628         /**
 629          * Retrieve a specific {@link Story}.
 630          *
 631          * @param luid
 632          *            the Library UID of the story
 633          * @param pg
 634          *            the optional progress reporter
 635          *
 636          * @return the corresponding {@link Story} or NULL if not found
 637          *
 638          * @throws IOException
 639          *             in case of IOException
 640          */
 641         public synchronized Story getStory(String luid, Progress pg)
 642                         throws IOException {
 643                 Progress pgMetas = new Progress();
 644                 Progress pgStory = new Progress();
 645                 if (pg != null) {
 646                         pg.setMinMax(0, 100);
 647                         pg.addProgress(pgMetas, 10);
 648                         pg.addProgress(pgStory, 90);
 649                 }
 650
 651                 MetaData meta = null;
 652                 for (MetaData oneMeta : getMetas(pgMetas)) {
 653                         if (oneMeta.getLuid().equals(luid)) {
 654                                 meta = oneMeta;
 655                                 break;
 656                         }
 657                 }
 658
 659                 pgMetas.done();
 660
 661                 Story story = getStory(luid, meta, pgStory);
 662                 pgStory.done();
 663
 664                 return story;
 665         }
 666
 667         /**
 668          * Retrieve a specific {@link Story}.
 669          *
 670          * @param luid
 671          *            the meta of the story
 672          * @param pg
 673          *            the optional progress reporter
 674          *
 675          * @return the corresponding {@link Story} or NULL if not found
 676          *
 677          * @throws IOException
 678          *             in case of IOException
 679          */
 680         public synchronized Story getStory(String luid,
 681                         @SuppressWarnings("javadoc") MetaData meta, Progress pg)
 682                         throws IOException {
 683
 684                 if (pg == null) {
 685                         pg = new Progress();
 686                 }
 687
 688                 Progress pgGet = new Progress();
 689                 Progress pgProcess = new Progress();
 690
 691                 pg.setMinMax(0, 2);
 692                 pg.addProgress(pgGet, 1);
 693                 pg.addProgress(pgProcess, 1);
 694
 695                 Story story = null;
 696                 File file = getFile(luid, pgGet);
 697                 pgGet.done();
 698                 try {
 699                         SupportType type = SupportType.valueOfAllOkUC(meta.getType());
 700                         URL url = file.toURI().toURL();
 701                         if (type != null) {
 702                                 story = BasicSupport.getSupport(type, url) //
 703                                                 .process(pgProcess);
 704
 705                                 // Because we do not want to clear the meta cache:
 706                                 meta.setCover(story.getMeta().getCover());
 707                                 meta.setResume(story.getMeta().getResume());
 708                                 story.setMeta(meta);
 709                                 //
 710                         } else {
 711                                 throw new IOException("Unknown type: " + meta.getType());
 712                         }
 713                 } catch (IOException e) {
 714                         // We should not have not-supported files in the
 715                         // library
 716                         Instance.getInstance().getTraceHandler().error(new IOException(
 717                                         String.format("Cannot load file of type '%s' from library: %s", meta.getType(), file), e));
 718                 } finally {
 719                         pgProcess.done();
 720                         pg.done();
 721                 }
 722
 723                 return story;
 724         }
 725
 726         /**
 727          * Import the {@link Story} at the given {@link URL} into the
 728          * {@link BasicLibrary}.
 729          *
 730          * @param url
 731          *            the {@link URL} to import
 732          * @param pg
 733          *            the optional progress reporter
 734          *
 735          * @return the imported Story {@link MetaData}
 736          *
 737          * @throws UnknownHostException
 738          *             if the host is not supported
 739          * @throws IOException
 740          *             in case of I/O error
 741          */
 742         public MetaData imprt(URL url, Progress pg) throws IOException {
 743                 if (pg == null)
 744                         pg = new Progress();
 745
 746                 pg.setMinMax(0, 1000);
 747                 Progress pgProcess = new Progress();
 748                 Progress pgSave = new Progress();
 749                 pg.addProgress(pgProcess, 800);
 750                 pg.addProgress(pgSave, 200);
 751
 752                 BasicSupport support = BasicSupport.getSupport(url);
 753                 if (support == null) {
 754                         throw new UnknownHostException("" + url);
 755                 }
 756
 757                 Story story = save(support.process(pgProcess), pgSave);
 758                 pg.done();
 759
 760                 return story.getMeta();
 761         }
 762
 763         /**
 764          * Import the story from one library to another, and keep the same LUID.
 765          *
 766          * @param other
 767          *            the other library to import from
 768          * @param luid
 769          *            the Library UID
 770          * @param pg
 771          *            the optional progress reporter
 772          *
 773          * @throws IOException
 774          *             in case of I/O error
 775          */
 776         public void imprt(BasicLibrary other, String luid, Progress pg)
 777                         throws IOException {
 778                 Progress pgGetStory = new Progress();
 779                 Progress pgSave = new Progress();
 780                 if (pg == null) {
 781                         pg = new Progress();
 782                 }
 783
 784                 pg.setMinMax(0, 2);
 785                 pg.addProgress(pgGetStory, 1);
 786                 pg.addProgress(pgSave, 1);
 787
 788                 Story story = other.getStory(luid, pgGetStory);
 789                 if (story != null) {
 790                         story = this.save(story, luid, pgSave);
 791                         pg.done();
 792                 } else {
 793                         pg.done();
 794                         throw new IOException("Cannot find story in Library: " + luid);
 795                 }
 796         }
 797
 798         /**
 799          * Export the {@link Story} to the given target in the given format.
 800          *
 801          * @param luid
 802          *            the {@link Story} ID
 803          * @param type
 804          *            the {@link OutputType} to transform it to
 805          * @param target
 806          *            the target to save to
 807          * @param pg
 808          *            the optional progress reporter
 809          *
 810          * @return the saved resource (the main saved {@link File})
 811          *
 812          * @throws IOException
 813          *             in case of I/O error
 814          */
 815         public File export(String luid, OutputType type, String target, Progress pg)
 816                         throws IOException {
 817                 Progress pgGetStory = new Progress();
 818                 Progress pgOut = new Progress();
 819                 if (pg != null) {
 820                         pg.setMax(2);
 821                         pg.addProgress(pgGetStory, 1);
 822                         pg.addProgress(pgOut, 1);
 823                 }
 824
 825                 BasicOutput out = BasicOutput.getOutput(type, false, false);
 826                 if (out == null) {
 827                         throw new IOException("Output type not supported: " + type);
 828                 }
 829
 830                 Story story = getStory(luid, pgGetStory);
 831                 if (story == null) {
 832                         throw new IOException("Cannot find story to export: " + luid);
 833                 }
 834
 835                 return out.process(story, target, pgOut);
 836         }
 837
 838         /**
 839          * Save a {@link Story} to the {@link BasicLibrary}.
 840          *
 841          * @param story
 842          *            the {@link Story} to save
 843          * @param pg
 844          *            the optional progress reporter
 845          *
 846          * @return the same {@link Story}, whose LUID may have changed
 847          *
 848          * @throws IOException
 849          *             in case of I/O error
 850          */
 851         public Story save(Story story, Progress pg) throws IOException {
 852                 return save(story, null, pg);
 853         }
 854
 855         /**
 856          * Save a {@link Story} to the {@link BasicLibrary} -- the LUID <b>must</b>
 857          * be correct, or NULL to get the next free one.
 858          * <p>
 859          * Will override any previous {@link Story} with the same LUID.
 860          *
 861          * @param story
 862          *            the {@link Story} to save
 863          * @param luid
 864          *            the <b>correct</b> LUID or NULL to get the next free one
 865          * @param pg
 866          *            the optional progress reporter
 867          *
 868          * @return the same {@link Story}, whose LUID may have changed
 869          *
 870          * @throws IOException
 871          *             in case of I/O error
 872          */
 873         public synchronized Story save(Story story, String luid, Progress pg)
 874                         throws IOException {
 875
 876                 Instance.getInstance().getTraceHandler().trace(this.getClass().getSimpleName() + ": saving story " + luid);
 877
 878                 // Do not change the original metadata, but change the original story
 879                 MetaData meta = story.getMeta().clone();
 880                 story.setMeta(meta);
 881
 882                 if (luid == null || luid.isEmpty()) {
 883                         meta.setLuid(String.format("%03d", getNextId()));
 884                 } else {
 885                         meta.setLuid(luid);
 886                 }
 887
 888                 if (luid != null && getInfo(luid) != null) {
 889                         delete(luid);
 890                 }
 891
 892                 story = doSave(story, pg);
 893
 894                 updateInfo(story.getMeta());
 895
 896                 Instance.getInstance().getTraceHandler()
 897                                 .trace(this.getClass().getSimpleName() + ": story saved (" + luid + ")");
 898
 899                 return story;
 900         }
 901
 902         /**
 903          * Delete the given {@link Story} from this {@link BasicLibrary}.
 904          *
 905          * @param luid
 906          *            the LUID of the target {@link Story}
 907          *
 908          * @throws IOException
 909          *             in case of I/O error
 910          */
 911         public synchronized void delete(String luid) throws IOException {
 912                 Instance.getInstance().getTraceHandler().trace(this.getClass().getSimpleName() + ": deleting story " + luid);
 913
 914                 doDelete(luid);
 915                 invalidateInfo(luid);
 916
 917                 Instance.getInstance().getTraceHandler()
 918                                 .trace(this.getClass().getSimpleName() + ": story deleted (" + luid
 919                                                 + ")");
 920         }
 921
 922         /**
 923          * Change the type (source) of the given {@link Story}.
 924          *
 925          * @param luid
 926          *            the {@link Story} LUID
 927          * @param newSource
 928          *            the new source
 929          * @param pg
 930          *            the optional progress reporter
 931          *
 932          * @throws IOException
 933          *             in case of I/O error or if the {@link Story} was not found
 934          */
 935         public synchronized void changeSource(String luid, String newSource,
 936                         Progress pg) throws IOException {
 937                 MetaData meta = getInfo(luid);
 938                 if (meta == null) {
 939                         throw new IOException("Story not found: " + luid);
 940                 }
 941
 942                 changeSTA(luid, newSource, meta.getTitle(), meta.getAuthor(), pg);
 943         }
 944
 945         /**
 946          * Change the title (name) of the given {@link Story}.
 947          *
 948          * @param luid
 949          *            the {@link Story} LUID
 950          * @param newTitle
 951          *            the new title
 952          * @param pg
 953          *            the optional progress reporter
 954          *
 955          * @throws IOException
 956          *             in case of I/O error or if the {@link Story} was not found
 957          */
 958         public synchronized void changeTitle(String luid, String newTitle,
 959                         Progress pg) throws IOException {
 960                 MetaData meta = getInfo(luid);
 961                 if (meta == null) {
 962                         throw new IOException("Story not found: " + luid);
 963                 }
 964
 965                 changeSTA(luid, meta.getSource(), newTitle, meta.getAuthor(), pg);
 966         }
 967
 968         /**
 969          * Change the author of the given {@link Story}.
 970          *
 971          * @param luid
 972          *            the {@link Story} LUID
 973          * @param newAuthor
 974          *            the new author
 975          * @param pg
 976          *            the optional progress reporter
 977          *
 978          * @throws IOException
 979          *             in case of I/O error or if the {@link Story} was not found
 980          */
 981         public synchronized void changeAuthor(String luid, String newAuthor,
 982                         Progress pg) throws IOException {
 983                 MetaData meta = getInfo(luid);
 984                 if (meta == null) {
 985                         throw new IOException("Story not found: " + luid);
 986                 }
 987
 988                 changeSTA(luid, meta.getSource(), meta.getTitle(), newAuthor, pg);
 989         }
 990
 991         /**
 992          * Change the Source, Title and Author of the {@link Story} in one single
 993          * go.
 994          *
 995          * @param luid
 996          *            the {@link Story} LUID
 997          * @param newSource
 998          *            the new source
 999          * @param newTitle
1000          *            the new title
1001          * @param newAuthor
1002          *            the new author
1003          * @param pg
1004          *            the optional progress reporter
1005          *
1006          * @throws IOException
1007          *             in case of I/O error or if the {@link Story} was not found
1008          */
1009         protected synchronized void changeSTA(String luid, String newSource,
1010                         String newTitle, String newAuthor, Progress pg) throws IOException {
1011                 MetaData meta = getInfo(luid);
1012                 if (meta == null) {
1013                         throw new IOException("Story not found: " + luid);
1014                 }
1015
1016                 meta.setSource(newSource);
1017                 meta.setTitle(newTitle);
1018                 meta.setAuthor(newAuthor);
1019                 saveMeta(meta, pg);
1020         }
1021
1022         /**
1023          * Save back the current state of the {@link MetaData} (LUID <b>MUST NOT</b>
1024          * change) for this {@link Story}.
1025          * <p>
1026          * By default, delete the old {@link Story} then recreate a new
1027          * {@link Story}.
1028          * <p>
1029          * Note that this behaviour can lead to data loss in case of problems!
1030          *
1031          * @param meta
1032          *            the new {@link MetaData} (LUID <b>MUST NOT</b> change)
1033          * @param pg
1034          *            the optional {@link Progress}
1035          *
1036          * @throws IOException
1037          *             in case of I/O error or if the {@link Story} was not found
1038          */
1039         protected synchronized void saveMeta(MetaData meta, Progress pg)
1040                         throws IOException {
1041                 if (pg == null) {
1042                         pg = new Progress();
1043                 }
1044
1045                 Progress pgGet = new Progress();
1046                 Progress pgSet = new Progress();
1047                 pg.addProgress(pgGet, 50);
1048                 pg.addProgress(pgSet, 50);
1049
1050                 Story story = getStory(meta.getLuid(), pgGet);
1051                 if (story == null) {
1052                         throw new IOException("Story not found: " + meta.getLuid());
1053                 }
1054
1055                 // TODO: this is not safe!
1056                 delete(meta.getLuid());
1057                 story.setMeta(meta);
1058                 save(story, meta.getLuid(), pgSet);
1059
1060                 pg.done();
1061         }
1062 }