framework/main/classes/stacker/file/class_BaseFileStack.php

   1 <?php
   2 // Own namespace
   3 namespace Org\Mxchange\CoreFramework\Stacker\Filesystem;
   4
   5 // Import framework stuff
   6 use Org\Mxchange\CoreFramework\Factory\Filesystem\Stack\FileStackIndexFactory;
   7 use Org\Mxchange\CoreFramework\Factory\ObjectFactory;
   8 use Org\Mxchange\CoreFramework\FileStack\InvalidMagicException;
   9 use Org\Mxchange\CoreFramework\Filesystem\File\BaseBinaryFile;
  10 use Org\Mxchange\CoreFramework\Generic\UnsupportedOperationException;
  11 use Org\Mxchange\CoreFramework\Index\Indexable;
  12 use Org\Mxchange\CoreFramework\Iterator\Filesystem\SeekableWritableFileIterator;
  13 use Org\Mxchange\CoreFramework\Stacker\BaseStacker;
  14 use Org\Mxchange\CoreFramework\Utils\String\StringUtils;
  15
  16 // Import SPL stuff
  17 use \SplFileInfo;
  18 use \UnexpectedValueException;
  19
  20 /**
  21  * A general file-based stack class
  22  *
  23  * @author              Roland Haeder <webmaster@ship-simu.org>
  24  * @version             0.0.0
  25  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2020 Core Developer Team
  26  * @license             GNU GPL 3.0 or any newer version
  27  * @link                http://www.ship-simu.org
  28  *
  29  * This program is free software: you can redistribute it and/or modify
  30  * it under the terms of the GNU General Public License as published by
  31  * the Free Software Foundation, either version 3 of the License, or
  32  * (at your option) any later version.
  33  *
  34  * This program is distributed in the hope that it will be useful,
  35  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  36  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  37  * GNU General Public License for more details.
  38  *
  39  * You should have received a copy of the GNU General Public License
  40  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  41  */
  42 abstract class BaseFileStack extends BaseStacker {
  43         // Exception codes
  44         const EXCEPTION_BAD_MAGIC = 0xe100;
  45
  46         /**
  47          * Magic for this stack
  48          */
  49         const STACK_MAGIC = 'STACKv0.1';
  50
  51         /**
  52          * Name of array index for gap position
  53          */
  54         const ARRAY_INDEX_GAP_POSITION = 'gap';
  55
  56         /**
  57          * Name of array index for hash
  58          */
  59         const ARRAY_INDEX_HASH = 'hash';
  60
  61         /**
  62          * Name of array index for length of raw data
  63          */
  64         const ARRAY_INDEX_DATA_LENGTH = 'length';
  65
  66         /**
  67          * An instance of an Indexable class
  68          */
  69         private $indexInstance = NULL;
  70
  71         /**
  72          * Protected constructor
  73          *
  74          * @param       $className      Name of the class
  75          * @return      void
  76          */
  77         protected function __construct (string $className) {
  78                 // Call parent constructor
  79                 parent::__construct($className);
  80         }
  81
  82         /**
  83          * Setter for Indexable instance
  84          *
  85          * @param       $indexInstance  An instance of an Indexable class
  86          * @return      void
  87          */
  88         protected final function setIndexInstance (Indexable $indexInstance) {
  89                 $this->indexInstance = $indexInstance;
  90         }
  91
  92         /**
  93          * Getter for Indexable instance
  94          *
  95          * @return      $indexInstance  An instance of an Indexable class
  96          */
  97         public final function getIndexInstance () {
  98                 return $this->indexInstance;
  99         }
 100
 101         /**
 102          * Reads the file header
 103          *
 104          * @return      void
 105          * @todo        To hard assertions here, better rewrite them to exceptions
 106          * @throws      UnexpectedValueException        If header is not proper length
 107          * @throws      InvalidMagicException   If a bad magic was found
 108          */
 109         public function readFileHeader () {
 110                 // First rewind to beginning as the header sits at the beginning ...
 111                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: CALLED!', __METHOD__, __LINE__));
 112                 $this->getIteratorInstance()->rewind();
 113
 114                 // Then read it (see constructor for calculation)
 115                 $data = $this->getIteratorInstance()->read($this->getIteratorInstance()->getHeaderSize());
 116                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: Read %d bytes (%d wanted).', strlen($data), $this->getIteratorInstance()->getHeaderSize()));
 117
 118                 // Have all requested bytes been read?
 119                 if (strlen($data) != $this->getIteratorInstance()->getHeaderSize()) {
 120                         // Bad data length
 121                         throw new UnexpectedValueException(sprintf('data(%d)=%s does not match iteratorInstance->headerSize=%d',
 122                                 strlen($data),
 123                                 $data,
 124                                 $this->getIteratorInstance()->getHeaderSize()
 125                         ));
 126                 }
 127
 128                 // Last character must be the separator
 129                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: data(-1)=%s', dechex(ord(substr($data, -1, 1)))));
 130                 if (substr($data, -1, 1) !== chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES)) {
 131                         // Not valid separator
 132                         throw new UnexpectedValueException(sprintf('data=%s does not have separator=%s at the end.',
 133                                 $data,
 134                                 BaseBinaryFile::SEPARATOR_HEADER_ENTRIES
 135                         ));
 136                 }
 137
 138                 // Okay, then remove it
 139                 $data = substr($data, 0, -1);
 140
 141                 // And update seek position
 142                 $this->getIteratorInstance()->updateSeekPosition();
 143
 144                 /*
 145                  * Now split it:
 146                  *
 147                  * 0 => magic
 148                  * 1 => total entries
 149                  * 2 => current seek position
 150                  */
 151                 $header = explode(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA), $data);
 152
 153                 // Set header here
 154                 $this->getIteratorInstance()->setHeader($header);
 155
 156                 // Check if the array has only 3 elements
 157                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: header(%d)=%s', count($header), print_r($header, true)));
 158                 if (count($header) != 3) {
 159                         // Header array count is not expected
 160                         throw new UnexpectedValueException(sprintf('data=%s has %d elements, expected 3',
 161                                 $data,
 162                                 count($header)
 163                         ));
 164                 } elseif ($header[0] != self::STACK_MAGIC) {
 165                         // Bad magic
 166                         throw new InvalidMagicException($data, self::EXCEPTION_BAD_MAGIC);
 167                 }
 168
 169                 // Check length of count and seek position
 170                 if (strlen($header[1]) != BaseBinaryFile::LENGTH_COUNT) {
 171                         // Count length not valid
 172                         throw new UnexpectedValueException(sprintf('header[1](%d)=%s is not expected %d length',
 173                                 strlen($header[1]),
 174                                 $header[1],
 175                                 BaseBinaryFile::LENGTH_COUNT
 176                         ));
 177                 } elseif (strlen($header[1]) != BaseBinaryFile::LENGTH_POSITION) {
 178                         // Position length not valid
 179                         throw new UnexpectedValueException(sprintf('header[2](%d)=%s is not expected %d length',
 180                                 strlen($header[1]),
 181                                 $header[1],
 182                                 BaseBinaryFile::LENGTH_POSITION
 183                         ));
 184                 }
 185
 186                 // Decode count and seek position
 187                 $header[1] = hex2bin($header[1]);
 188                 $header[2] = hex2bin($header[2]);
 189
 190                 // Trace message
 191                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: EXIT!', __METHOD__, __LINE__));
 192         }
 193
 194         /**
 195          * Flushes the file header
 196          *
 197          * @return      void
 198          */
 199         public function flushFileHeader () {
 200                 // Put all informations together
 201                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: CALLED!', __METHOD__, __LINE__));
 202                 $header = sprintf('%s%s%s%s%s%s',
 203                         // Magic
 204                         self::STACK_MAGIC,
 205
 206                         // Separator magic<->count
 207                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 208
 209                         // Total entries (will be zero) and pad it to 20 chars
 210                         str_pad(StringUtils::dec2hex($this->getIteratorInstance()->getCounter()), BaseBinaryFile::LENGTH_COUNT, '0', STR_PAD_LEFT),
 211
 212                         // Separator count<->seek position
 213                         chr(BaseBinaryFile::SEPARATOR_HEADER_DATA),
 214
 215                         // Position (will be zero)
 216                         str_pad(StringUtils::dec2hex($this->getIteratorInstance()->getSeekPosition(), 2), BaseBinaryFile::LENGTH_POSITION, '0', STR_PAD_LEFT),
 217
 218                         // Separator position<->entries
 219                         chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES)
 220                 );
 221
 222                 // Write it to disk (header is always at seek position 0)
 223                 $this->getIteratorInstance()->writeData(0, $header, false);
 224
 225                 // Trace message
 226                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: EXIT!', __METHOD__, __LINE__));
 227         }
 228
 229         /**
 230          * Initializes this file-based stack.
 231          *
 232          * @param       $fileInfoInstance       An instance of a SplFileInfo class
 233          * @param       $type           Type of this stack (e.g. url_source for URL sources)
 234          * @return      void
 235          * @todo        Currently the stack file is not cached, please implement a memory-handling class and if enough RAM is found, cache the whole stack file.
 236          */
 237         protected function initFileStack (SplFileInfo $fileInfoInstance, string $type) {
 238                 // Get a stack file instance
 239                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: fileInfoInstance=%s,type=%s - CALLED!', $fileInfoInstance, $type));
 240                 $fileInstance = ObjectFactory::createObjectByConfiguredName('stack_file_class', array($fileInfoInstance, $this));
 241
 242                 // Get iterator instance
 243                 $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_iterator_class', array($fileInstance));
 244
 245                 // Set iterator here
 246                 $this->setIteratorInstance($iteratorInstance);
 247
 248                 // Calculate header size
 249                 $this->getIteratorInstance()->setHeaderSize(
 250                         strlen(self::STACK_MAGIC) +
 251                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 252                         BaseBinaryFile::LENGTH_COUNT +
 253                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_DATA)) +
 254                         BaseBinaryFile::LENGTH_POSITION +
 255                         strlen(chr(BaseBinaryFile::SEPARATOR_HEADER_ENTRIES))
 256                 );
 257
 258                 // Init counters and gaps array
 259                 $this->getIteratorInstance()->initCountersGapsArray();
 260
 261                 // Is the file's header initialized?
 262                 if (!$this->getIteratorInstance()->isFileHeaderInitialized()) {
 263                         // No, then create it (which may pre-allocate the stack)
 264                         $this->getIteratorInstance()->createFileHeader();
 265
 266                         // And pre-allocate a bit
 267                         $this->getIteratorInstance()->preAllocateFile('file_stack');
 268                 }
 269
 270                 // Load the file header
 271                 $this->readFileHeader();
 272
 273                 // Count all entries in file
 274                 $this->getIteratorInstance()->analyzeFile();
 275
 276                 /*
 277                  * Get stack index instance. This can be used for faster
 278                  * "defragmentation" and startup.
 279                  */
 280                 $indexInstance = FileStackIndexFactory::createFileStackIndexInstance($fileInfoInstance, $type);
 281
 282                 // And set it here
 283                 $this->setIndexInstance($indexInstance);
 284         }
 285
 286         /**
 287          * Adds a value to given stack
 288          *
 289          * @param       $stackerName    Name of the stack
 290          * @param       $value                  Value to add to this stacker
 291          * @return      void
 292          * @throws      FullStackerException    If the stack is full
 293          * @throws      InvalidArgumentException        Not all variable types are wanted here
 294          */
 295         protected function addValue (string $stackerName, $value) {
 296                 // Do some tests
 297                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('stackerName=%s,value[%s]=%s - CALLED!', $stackerName, gettype($value), print_r($value, true)));
 298                 if ($this->isStackFull($stackerName)) {
 299                         // Stacker is full
 300                         throw new FullStackerException(array($this, $stackerName, $value), self::EXCEPTION_STACKER_IS_FULL);
 301                 } elseif (is_resource($value) || is_object($value)) {
 302                         // Not wanted type
 303                         throw new InvalidArgumentException(sprintf('value[]=%s is not supported', gettype($value)));
 304                 }
 305
 306                 /*
 307                  * Now add the value to the file stack which returns gap position, a
 308                  * hash and length of the raw data.
 309                  */
 310                 $data = $this->getIteratorInstance()->writeValueToFile($stackerName, $value);
 311
 312                 // Add the hash and gap position to the index
 313                 $this->getIndexInstance()->addHashToIndex($stackerName, $data);
 314         }
 315
 316         /**
 317          * Get last value from named stacker
 318          *
 319          * @param       $stackerName    Name of the stack
 320          * @return      $value                  Value of last added value
 321          * @throws      EmptyStackerException   If the stack is empty
 322          */
 323         protected function getLastValue (string $stackerName) {
 324                 // Is the stack not yet initialized or full?
 325                 if ($this->isStackEmpty($stackerName)) {
 326                         // Throw an exception
 327                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 328                 } // END - if
 329
 330                 // Now get the last value
 331                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 332                 $value = NULL;
 333
 334                 // Return it
 335                 return $value;
 336         }
 337
 338         /**
 339          * Get first value from named stacker
 340          *
 341          * @param       $stackerName    Name of the stack
 342          * @return      $value                  Value of last added value
 343          * @throws      EmptyStackerException   If the stack is empty
 344          */
 345         protected function getFirstValue (string $stackerName) {
 346                 // Is the stack not yet initialized or full?
 347                 if ($this->isStackEmpty($stackerName)) {
 348                         // Throw an exception
 349                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 350                 } // END - if
 351
 352                 // Now get the first value
 353                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 354                 $value = NULL;
 355
 356                 // Return it
 357                 return $value;
 358         }
 359
 360         /**
 361          * "Pops" last entry from stack
 362          *
 363          * @param       $stackerName    Name of the stack
 364          * @return      $value                  Value "poped" from array
 365          * @throws      EmptyStackerException   If the stack is empty
 366          */
 367         protected function popLast (string $stackerName) {
 368                 // Is the stack not yet initialized or full?
 369                 if ($this->isStackEmpty($stackerName)) {
 370                         // Throw an exception
 371                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 372                 } // END - if
 373
 374                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 375                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 376                 return NULL;
 377         }
 378
 379         /**
 380          * "Pops" first entry from stack
 381          *
 382          * @param       $stackerName    Name of the stack
 383          * @return      $value                  Value "shifted" from array
 384          * @throws      EmptyStackerException   If the named stacker is empty
 385          */
 386         protected function popFirst (string $stackerName) {
 387                 // Is the stack not yet initialized or full?
 388                 if ($this->isStackEmpty($stackerName)) {
 389                         // Throw an exception
 390                         throw new EmptyStackerException(array($this, $stackerName), self::EXCEPTION_STACKER_IS_EMPTY);
 391                 } // END - if
 392
 393                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 394                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 395                 return NULL;
 396         }
 397
 398         /**
 399          * Checks whether the given stack is full
 400          *
 401          * @param       $stackerName    Name of the stack
 402          * @return      $isFull                 Whether the stack is full
 403          */
 404         protected function isStackFull (string $stackerName) {
 405                 // File-based stacks will only run full if the disk space is low.
 406                 // @TODO Please implement this, returning false
 407                 $isFull = false;
 408
 409                 // Return result
 410                 return $isFull;
 411         }
 412
 413         /**
 414          * Checks whether the given stack is empty
 415          *
 416          * @param       $stackerName            Name of the stack
 417          * @return      $isEmpty                        Whether the stack is empty
 418          * @throws      NoStackerException      If given stack is missing
 419          */
 420         public function isStackEmpty (string $stackerName) {
 421                 // So, is the stack empty?
 422                 $isEmpty = (($this->getStackCount($stackerName)) == 0);
 423
 424                 // Return result
 425                 return $isEmpty;
 426         }
 427
 428         /**
 429          * Initializes given stacker
 430          *
 431          * @param       $stackerName    Name of the stack
 432          * @param       $forceReInit    Force re-initialization
 433          * @return      void
 434          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 435          */
 436         public function initStack (string $stackerName, bool $forceReInit = false) {
 437                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 438         }
 439
 440         /**
 441          * Initializes all stacks
 442          *
 443          * @return      void
 444          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 445          */
 446         public function initStacks (array $stacks, bool $forceReInit = false) {
 447                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 448         }
 449
 450         /**
 451          * Checks whether the given stack is initialized (set in array $stackers)
 452          *
 453          * @param       $stackerName    Name of the stack
 454          * @return      $isInitialized  Whether the stack is initialized
 455          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 456          */
 457         public function isStackInitialized (string $stackerName) {
 458                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 459         }
 460
 461         /**
 462          * Determines whether the EOF has been reached
 463          *
 464          * @return      $isEndOfFileReached             Whether the EOF has been reached
 465          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 466          */
 467         public function isEndOfFileReached () {
 468                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 469         }
 470
 471         /**
 472          * Getter for size of given stack (array count)
 473          *
 474          * @param       $stackerName    Name of the stack
 475          * @return      $count                  Size of stack (array count)
 476          */
 477         public function getStackCount (string $stackerName) {
 478                 // Now, simply return the found count value, this must be up-to-date then!
 479                 return $this->getIteratorInstance()->getCounter();
 480         }
 481
 482         /**
 483          * Calculates minimum length for one entry/block
 484          *
 485          * @return      $length         Minimum length for one entry/block
 486          */
 487         public function calculateMinimumBlockLength () {
 488                 // Calulcate it
 489                 $length =
 490                         // Length of entry group
 491                         BaseBinaryFile::LENGTH_GROUP + strlen(chr(BaseBinaryFile::SEPARATOR_GROUP_HASH)) +
 492                         // Hash + value
 493                         self::getHashLength() + strlen(chr(BaseBinaryFile::SEPARATOR_HASH_VALUE)) + 1 +
 494                         // Final separator
 495                         strlen(chr(BaseBinaryFile::SEPARATOR_ENTRIES));
 496
 497                 // Return it
 498                 return $length;
 499         }
 500
 501         /**
 502          * Initializes counter for valid entries, arrays for damaged entries and
 503          * an array for gap seek positions. If you call this method on your own,
 504          * please re-analyze the file structure. So you are better to call
 505          * analyzeFile() instead of this method.
 506          *
 507          * @return      void
 508          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 509          */
 510         public function initCountersGapsArray () {
 511                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 512         }
 513
 514         /**
 515          * Getter for header size
 516          *
 517          * @return      $totalEntries   Size of file header
 518          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 519          */
 520         public final function getHeaderSize () {
 521                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 522         }
 523
 524         /**
 525          * Setter for header size
 526          *
 527          * @param       $headerSize             Size of file header
 528          * @return      void
 529          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 530          */
 531         public final function setHeaderSize (int $headerSize) {
 532                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 533         }
 534
 535         /**
 536          * Getter for header array
 537          *
 538          * @return      $totalEntries   Size of file header
 539          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 540          */
 541         public final function getHeader () {
 542                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 543         }
 544
 545         /**
 546          * Setter for header
 547          *
 548          * @param       $header         Array for a file header
 549          * @return      void
 550          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 551          */
 552         public final function setHeader (array $header) {
 553                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 554         }
 555
 556         /**
 557          * Updates seekPosition attribute from file to avoid to much access on file.
 558          *
 559          * @return      void
 560          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 561          */
 562         public function updateSeekPosition () {
 563                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 564         }
 565
 566         /**
 567          * Getter for total entries
 568          *
 569          * @return      $totalEntries   Total entries in this file
 570          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 571          */
 572         public final function getCounter () {
 573                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 574         }
 575
 576         /**
 577          * Writes data at given position
 578          *
 579          * @param       $seekPosition   Seek position
 580          * @param       $data                   Data to be written
 581          * @param       $flushHeader    Whether to flush the header (default: flush)
 582          * @return      void
 583          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 584          */
 585         public function writeData (int $seekPosition, string $data, bool $flushHeader = true) {
 586                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: seekPosition=%s,data[]=%s,flushHeader=%d', $seekPosition, gettype($data), intval($flushHeader)));
 587                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 588         }
 589
 590         /**
 591          * Writes given value to the file and returns a hash and gap position for it
 592          *
 593          * @param       $groupId        Group identifier
 594          * @param       $value          Value to be added to the stack
 595          * @return      $data           Hash and gap position
 596          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 597          */
 598         public function writeValueToFile (string $groupId, $value) {
 599                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,value[%s]=%s', $groupId, gettype($value), print_r($value, true)));
 600                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 601         }
 602
 603         /**
 604          * Searches for next suitable gap the given length of data can fit in
 605          * including padding bytes.
 606          *
 607          * @param       $length                 Length of raw data
 608          * @return      $seekPosition   Found next gap's seek position
 609          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 610          */
 611         public function searchNextGap (int $length) {
 612                 // Not supported here
 613                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: length=%d - CALLED!', $length));
 614                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getPointerInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 615         }
 616
 617         /**
 618          * "Getter" for file size
 619          *
 620          * @return      $fileSize       Size of currently loaded file
 621          */
 622         public function getFileSize () {
 623                 // Call iterator's method
 624                 return $this->getIteratorInstance()->getFileSize();
 625         }
 626
 627         /**
 628          * Writes given raw data to the file and returns a gap position and length
 629          *
 630          * @param       $groupId        Group identifier
 631          * @param       $hash           Hash from encoded value
 632          * @param       $encoded        Encoded value to be written to the file
 633          * @return      $data           Gap position and length of the raw data
 634          */
 635         public function writeDataToFreeGap (string $groupId, string $hash, string $encoded) {
 636                 // Raw data been written to the file
 637                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,hash=%s,encoded()=%d - CALLED!', $groupId, $hash, strlen($encoded)));
 638                 $rawData = sprintf('%s%s%s%s%s',
 639                         $groupId,
 640                         BaseBinaryFile::SEPARATOR_GROUP_HASH,
 641                         hex2bin($hash),
 642                         BaseBinaryFile::SEPARATOR_HASH_VALUE,
 643                         $encoded
 644                 );
 645
 646                 // Search for next free gap
 647                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,hash=%s,rawData()=%d', $groupId, $hash, strlen($rawData)));
 648                 $gapPosition = $this->getIteratorInstance()->searchNextGap(strlen($rawData));
 649
 650                 // Gap position cannot be smaller than header length + 1
 651                 if ($gapPosition <= $this->getIteratorInstance()->getHeaderSize()) {
 652                         // Improper gap position
 653                         throw new UnexpectedValueException(sprintf('gapPosition[%s]=%d is not larger than headerSize=%d',
 654                                 gettype($gapPosition),
 655                                 $gapPosition,
 656                                 $this->getIteratorInstance()->getHeaderSize()
 657                         ));
 658                 }
 659
 660                 // Then write the data at that gap
 661                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,hash=%s,gapPosition=%s', $groupId, $hash, $gapPosition));
 662                 $this->getIteratorInstance()->writeData($gapPosition, $rawData);
 663
 664                 // Return gap position, hash and length of raw data
 665                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: groupId=%s,hash=%s,rawData()=%d - EXIT!', $groupId, $hash, strlen($rawData)));
 666                 return [
 667                         self::ARRAY_INDEX_GAP_POSITION => $gapPosition,
 668                         self::ARRAY_INDEX_HASH         => $hash,
 669                         self::ARRAY_INDEX_DATA_LENGTH  => strlen($rawData),
 670                 ];
 671         }
 672
 673 }