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

   1 <?php
   2 // Own namespace
   3 namespace Org\Mxchange\CoreFramework\Stack\File;
   4
   5 // Import framework stuff
   6 use Org\Mxchange\CoreFramework\Factory\Stack\File\FileStackIndexFactory;
   7 use Org\Mxchange\CoreFramework\Factory\Object\ObjectFactory;
   8 use Org\Mxchange\CoreFramework\Filesystem\File\BaseBinaryFile;
   9 use Org\Mxchange\CoreFramework\Filesystem\File\BinaryFile;
  10 use Org\Mxchange\CoreFramework\Generic\UnsupportedOperationException;
  11 use Org\Mxchange\CoreFramework\Stack\BaseStacker;
  12 use Org\Mxchange\CoreFramework\Traits\Index\IndexableTrait;
  13 use Org\Mxchange\CoreFramework\Traits\Iterator\IteratorTrait;
  14 use Org\Mxchange\CoreFramework\Utils\Strings\StringUtils;
  15 use Org\Mxchange\CoreFramework\Utils\Arrays\ArrayUtils;
  16
  17 // Import SPL stuff
  18 use \InvalidArgumentException;
  19 use \SplFileInfo;
  20 use \UnexpectedValueException;
  21
  22 /**
  23  * A general file-based stack class
  24  *
  25  * @author              Roland Haeder <webmaster@ship-simu.org>
  26  * @version             0.0.0
  27  * @copyright   Copyright (c) 2007, 2008 Roland Haeder, 2009 - 2021 Core Developer Team
  28  * @license             GNU GPL 3.0 or any newer version
  29  * @link                http://www.ship-simu.org
  30  *
  31  * This program is free software: you can redistribute it and/or modify
  32  * it under the terms of the GNU General Public License as published by
  33  * the Free Software Foundation, either version 3 of the License, or
  34  * (at your option) any later version.
  35  *
  36  * This program is distributed in the hope that it will be useful,
  37  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  38  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  39  * GNU General Public License for more details.
  40  *
  41  * You should have received a copy of the GNU General Public License
  42  * along with this program.  If not, see <http://www.gnu.org/licenses/>.
  43  */
  44 abstract class BaseFileStack extends BaseStacker {
  45         // Load traits
  46         use IndexableTrait;
  47         use IteratorTrait;
  48
  49         // Exception codes
  50         const EXCEPTION_BAD_MAGIC = 0xe100;
  51
  52         /**
  53          * Minimum block length
  54          */
  55         private static $minimumBlockLength = 0;
  56
  57         /**
  58          * Protected constructor
  59          *
  60          * @param       $className      Name of the class
  61          * @return      void
  62          */
  63         protected function __construct (string $className) {
  64                 // Call parent constructor
  65                 parent::__construct($className);
  66         }
  67
  68         /**
  69          * Reads the file header
  70          *
  71          * @return      void
  72          * @todo        To hard assertions here, better rewrite them to exceptions
  73          * @throws      UnexpectedValueException        If header is not proper length
  74          * @throws      InvalidMagicException   If a bad magic was found
  75          */
  76         public function readStackHeader () {
  77                 // First rewind to beginning as the header sits at the beginning ...
  78                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: CALLED!');
  79                 $this->getIteratorInstance()->rewind();
  80
  81                 // Get header size
  82                 $headerSize = $this->getIteratorInstance()->getBinaryFileInstance()->getHeaderSize();
  83
  84                 // Then read it (see constructor for calculation)
  85                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: headerSize=%d', $headerSize));
  86                 $data = $this->getIteratorInstance()->getBinaryFileInstance()->read($headerSize);
  87
  88                 // Have all requested bytes been read?
  89                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: Read %d bytes (%d wanted).', strlen($data), $this->getIteratorInstance()->getBinaryFileInstance()->getHeaderSize()));
  90                 if (strlen($data) != $this->getIteratorInstance()->getBinaryFileInstance()->getHeaderSize()) {
  91                         // Bad data length
  92                         throw new UnexpectedValueException(sprintf('data(%d)=%s does not match iteratorInstance->headerSize=%d',
  93                                 strlen($data),
  94                                 $data,
  95                                 $this->getIteratorInstance()->getBinaryFileInstance()->getHeaderSize()
  96                         ));
  97                 } elseif (empty(trim($data, chr(0)))) {
  98                         // Empty header, file is freshly pre-allocated
  99                         /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: Empty file header detected - EXIT!');
 100                         return;
 101                 }
 102
 103                 // Last character must be the separator
 104                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: data(-1)=%s', dechex(ord(substr($data, -1, 1)))));
 105                 if (substr($data, -1, 1) !== chr(BinaryFile::SEPARATOR_HEADER_ENTRIES)) {
 106                         // Not valid separator
 107                         throw new UnexpectedValueException(sprintf('data=%s does not have separator=%s at the end.',
 108                                 $data,
 109                                 BinaryFile::SEPARATOR_HEADER_ENTRIES
 110                         ));
 111                 }
 112
 113                 // Okay, then remove it
 114                 $data = substr($data, 0, -1);
 115
 116                 // And update seek position
 117                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: Calling this->iteratorInstance->updateSeekPosition() ...');
 118                 $this->getIteratorInstance()->getBinaryFileInstance()->updateSeekPosition();
 119
 120                 /*
 121                  * Now split it:
 122                  *
 123                  * 0 => magic
 124                  * 1 => total entries
 125                  * 2 => current seek position
 126                  */
 127                 $header = explode(chr(BinaryFile::SEPARATOR_HEADER_DATA), $data);
 128
 129                 // Map numeric indexes to associative indexes
 130                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: header()=%d', count($header)));
 131                 $header = ArrayUtils::mapNumericKeysToAssociative($header, [
 132                         BinaryFile::HEADER_NAME_MAGIC,
 133                         BinaryFile::HEADER_NAME_TOTAL_ENTRIES,
 134                         BinaryFile::HEADER_NAME_SEEK_POSITION,
 135                 ]);
 136
 137                 // Check if the array has only 3 elements
 138                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: HEADER_ELEMENT_COUNT=%d,header(%d)=%s', BinaryFile::HEADER_ELEMENT_COUNT, count($header), print_r($header, true)));
 139                 if (count($header) != BinaryFile::HEADER_ELEMENT_COUNT) {
 140                         // Header array count is not expected
 141                         throw new UnexpectedValueException(sprintf('data=%s has %d elements, but expected is %d',
 142                                 $data,
 143                                 count($header),
 144                                 BinaryFile::HEADER_ELEMENT_COUNT
 145                         ));
 146                 } elseif ($header[BinaryFile::HEADER_NAME_MAGIC] != StackableFile::STACK_MAGIC) {
 147                         // Bad magic
 148                         throw new InvalidMagicException($data, self::EXCEPTION_BAD_MAGIC);
 149                 }
 150
 151                 // Check length of count and seek position
 152                 if (strlen($header[BinaryFile::HEADER_NAME_TOTAL_ENTRIES]) != BinaryFile::LENGTH_COUNT) {
 153                         // Count length not valid
 154                         throw new UnexpectedValueException(sprintf('header[%s](%d)=%s is not expected %d length',
 155                                 BinaryFile::HEADER_NAME_TOTAL_ENTRIES,
 156                                 strlen($header[BinaryFile::HEADER_NAME_TOTAL_ENTRIES]),
 157                                 $header[BinaryFile::HEADER_NAME_TOTAL_ENTRIES],
 158                                 BinaryFile::LENGTH_COUNT
 159                         ));
 160                 } elseif (strlen($header[BinaryFile::HEADER_NAME_SEEK_POSITION]) != BinaryFile::LENGTH_POSITION) {
 161                         // Position length not valid
 162                         throw new UnexpectedValueException(sprintf('header[%s](%d)=%s is not expected %d length',
 163                                 BinaryFile::HEADER_NAME_SEEK_POSITION,
 164                                 strlen($header[BinaryFile::HEADER_NAME_SEEK_POSITION]),
 165                                 $header[BinaryFile::HEADER_NAME_SEEK_POSITION],
 166                                 BinaryFile::LENGTH_POSITION
 167                         ));
 168                 }
 169
 170                 // Decode count and seek position
 171                 $header[BinaryFile::HEADER_NAME_TOTAL_ENTRIES] = hex2bin($header[BinaryFile::HEADER_NAME_TOTAL_ENTRIES]);
 172                 $header[BinaryFile::HEADER_NAME_SEEK_POSITION] = hex2bin($header[BinaryFile::HEADER_NAME_SEEK_POSITION]);
 173
 174                 // Set header here
 175                 $this->getIteratorInstance()->getBinaryFileInstance()->setHeader($header);
 176
 177                 // Trace message
 178                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: EXIT!');
 179         }
 180
 181         /**
 182          * Flushes the file header
 183          *
 184          * @return      void
 185          */
 186         public function flushFileHeader () {
 187                 // Put all informations together
 188                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: CALLED!');
 189                 $header = sprintf('%s%s%s%s%s%s',
 190                         // Magic
 191                         StackableFile::STACK_MAGIC,
 192
 193                         // Separator magic<->count
 194                         chr(BinaryFile::SEPARATOR_HEADER_DATA),
 195
 196                         // Padded total entries
 197                         str_pad(StringUtils::dec2hex($this->getIteratorInstance()->getBinaryFileInstance()->getCounter()), BinaryFile::LENGTH_COUNT, '0', STR_PAD_LEFT),
 198
 199                         // Separator count<->seek position
 200                         chr(BinaryFile::SEPARATOR_HEADER_DATA),
 201
 202                         // Padded seek position
 203                         str_pad(StringUtils::dec2hex($this->getIteratorInstance()->getBinaryFileInstance()->getSeekPosition(), 2), BinaryFile::LENGTH_POSITION, '0', STR_PAD_LEFT),
 204
 205                         // Separator position<->entries
 206                         chr(BinaryFile::SEPARATOR_HEADER_ENTRIES)
 207                 );
 208
 209                 // Write it to disk (header is always at seek position 0)
 210                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: Calling this->iteratorInstance->writeAtPosition(0, header=%s) ...', $header));
 211                 $this->getIteratorInstance()->getBinaryFileInstance()->writeAtPosition(0, $header);
 212
 213                 // Trace message
 214                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: EXIT!');
 215         }
 216
 217         /**
 218          * Initializes this file-based stack.
 219          *
 220          * @param       $fileInfoInstance       An instance of a SplFileInfo class
 221          * @param       $type           Type of this stack (e.g. url_source for URL sources)
 222          * @return      void
 223          * @throws      InvalidArgumentException        If a parameter is invalid
 224          * @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.
 225          */
 226         protected function initFileStack (SplFileInfo $fileInfoInstance, string $type) {
 227                 // Validate parameter
 228                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: fileInfoInstance[%s]=%s,type=%s - CALLED!', get_class($fileInfoInstance), $fileInfoInstance, $type));
 229                 if (empty($type)) {
 230                         // Invalid parameter
 231                         throw new InvalidArgumentException('Parameter "type" is empty');
 232                 }
 233
 234                 // Get a stack file instance
 235                 $stackInstance = ObjectFactory::createObjectByConfiguredName('stack_file_class', array($fileInfoInstance, $this));
 236
 237                 // Get iterator instance
 238                 $iteratorInstance = ObjectFactory::createObjectByConfiguredName('file_iterator_class', array($stackInstance));
 239
 240                 // Set iterator here
 241                 $this->setIteratorInstance($iteratorInstance);
 242
 243                 // Calculate header size
 244                 $headerSize = (
 245                         strlen(StackableFile::STACK_MAGIC) +
 246                         strlen(chr(BinaryFile::SEPARATOR_HEADER_DATA)) +
 247                         BinaryFile::LENGTH_COUNT +
 248                         strlen(chr(BinaryFile::SEPARATOR_HEADER_DATA)) +
 249                         BinaryFile::LENGTH_POSITION +
 250                         strlen(chr(BinaryFile::SEPARATOR_HEADER_ENTRIES))
 251                 );
 252
 253                 // Setting it
 254                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: Setting headerSize=%d ...', $headerSize));
 255                 $this->getIteratorInstance()->getBinaryFileInstance()->setHeaderSize($headerSize);
 256
 257                 // Init counters and gaps array
 258                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: Calling this->iteratorInstance->initCountersGapsArray() ...');
 259                 $this->getIteratorInstance()->getBinaryFileInstance()->initCountersGapsArray();
 260
 261                 /*
 262                  * Get stack index instance. This can be used for faster
 263                  * "defragmentation" and startup.
 264                  */
 265                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: Creating index instance for fileInfoInstance[%s]=%s,type=%s ...', get_class($fileInfoInstance), $fileInfoInstance, $type));
 266                 $indexInstance = FileStackIndexFactory::createFileStackIndexInstance($fileInfoInstance, $type);
 267
 268                 // And set it here
 269                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: indexInstance=%s', $indexInstance->__toString()));
 270                 $this->setIndexInstance($indexInstance);
 271
 272                 // Is the file's header initialized?
 273                 if (!$this->getIteratorInstance()->getBinaryFileInstance()->isFileHeaderInitialized()) {
 274                         // First pre-allocate a bit
 275                         /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: Calling this->iteratorInstance->preAllocateFile(file_stack) ...');
 276                         $this->getIteratorInstance()->getBinaryFileInstance()->preAllocateFile('file_stack');
 277
 278                         // Then create file header
 279                         /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: this->iteratorInstance->createFileHeader() ...');
 280                         $this->getIteratorInstance()->getBinaryFileInstance()->createFileHeader();
 281                 }
 282
 283                 // Load the file header
 284                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: Calling this->readStackHeader() ...');
 285                 $this->readStackHeader();
 286
 287                 // Is the index loaded correctly and the stack file is just created?
 288                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: Calling this->indexInstance->isIndexLoaded() ...');
 289                 if (!$this->getIndexInstance()->isIndexLoaded()) {
 290                         /*
 291                          * Something horrible has happened to the index as it should be
 292                          * loaded at this point. The stack's file structure then needs to
 293                          * be analyzed and the index rebuild.
 294                          */
 295                         /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: Calling this->iteratorInstance->analyzeFileStructure() ...');
 296                         $this->getIteratorInstance()->getBinaryFileInstance()->analyzeFileStructure();
 297
 298                         // Rebuild index from file
 299                         /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: Calling this->iteratorInstance->rebuildIndexFromStack(%s) ...', $this->__toString()));
 300                         $this->getIndexInstance()->rebuildIndexFromStack($this);
 301                 }
 302
 303                 // Trace message
 304                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: EXIT!');
 305         }
 306
 307         /**
 308          * Adds a value to given stack
 309          *
 310          * @param       $stackerName    Name of the stack
 311          * @param       $value                  Value to add to this stacker
 312          * @return      void
 313          * @throws      FullStackerException    If the stack is full
 314          * @throws      InvalidArgumentException        If a parameter is not valid
 315          * @throws      InvalidArgumentException        Not all variable types are wanted here
 316          */
 317         protected function addValueToStack (string $stackerName, $value) {
 318                 // Validate parameter
 319                 /* PRINTR-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s,value[]=%s - CALLED!', $stackerName, gettype($value)));
 320                 //* PRINTR-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s,value[%s]=%s', $stackerName, gettype($value), print_r($value, true)));
 321                 if (empty($stackerName)) {
 322                         // No empty stack name
 323                         throw new InvalidArgumentException('Parameter "stackerName" is empty');
 324                 } elseif ($this->isStackFull($stackerName)) {
 325                         // Stacker is full
 326                         throw new FullStackerException([$this, $stackerName, $value], self::EXCEPTION_STACKER_IS_FULL);
 327                 } elseif (is_resource($value) || is_object($value)) {
 328                         // Not wanted type
 329                         throw new InvalidArgumentException(sprintf('value[]=%s is not supported', gettype($value)));
 330                 }
 331
 332                 /*
 333                  * Now add the value to the file stack which returns gap position, a
 334                  * hash and length of the raw data.
 335                  */
 336                 $data = $this->getIteratorInstance()->getBinaryFileInstance()->writeValueToFile($stackerName, $value);
 337
 338                 // Add the hash and gap position to the index
 339                 //* PRINTR-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: data=%s', print_r($data, true));
 340                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: Calling this->indexInstance->addHashedDataToIndex(%s,data()=%d) ...', $stackerName, count($data)));
 341                 $this->getIndexInstance()->addHashedDataToIndex($stackerName, $data);
 342
 343                 // Trace message
 344                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: EXIT!');
 345         }
 346
 347         /**
 348          * Get last value from named stacker
 349          *
 350          * @param       $stackerName    Name of the stack
 351          * @return      $value                  Value of last added value
 352          * @throws      InvalidArgumentException        If a parameter is not valid
 353          * @throws      BadMethodCallException  If the stack is empty
 354          */
 355         protected function getLastValue (string $stackerName) {
 356                 // Validate parameter
 357                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
 358                 if (empty($stackerName)) {
 359                         // No empty stack name
 360                         throw new InvalidArgumentException('Parameter "stackerName" is empty');
 361                 } elseif ($this->isStackEmpty($stackerName)) {
 362                         // Throw an exception
 363                         throw new BadMethodCallException([$this, $stackerName], self::EXCEPTION_STACKER_IS_EMPTY);
 364                 }
 365
 366                 // Now get the last value
 367                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 368                 $value = NULL;
 369
 370                 // Return it
 371                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: value[]=%s - EXIT!', gettype($value)));
 372                 return $value;
 373         }
 374
 375         /**
 376          * Get first value from named stacker
 377          *
 378          * @param       $stackerName    Name of the stack
 379          * @return      $value                  Value of last added value
 380          * @throws      InvalidArgumentException        If a parameter is not valid
 381          * @throws      BadMethodCallException  If the stack is empty
 382          */
 383         protected function getFirstValue (string $stackerName) {
 384                 // Validate parameter
 385                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
 386                 if (empty($stackerName)) {
 387                         // No empty stack name
 388                         throw new InvalidArgumentException('Parameter "stackerName" is empty');
 389                 } elseif ($this->isStackEmpty($stackerName)) {
 390                         // Throw an exception
 391                         throw new BadMethodCallException([$this, $stackerName], self::EXCEPTION_STACKER_IS_EMPTY);
 392                 }
 393
 394                 // Now get the first value
 395                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 396                 $value = NULL;
 397
 398                 // Return it
 399                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: value[]=%s - EXIT!', gettype($value)));
 400                 return $value;
 401         }
 402
 403         /**
 404          * "Pops" last entry from stack
 405          *
 406          * @param       $stackerName    Name of the stack
 407          * @return      $value                  Value "poped" from array
 408          * @throws      InvalidArgumentException        If a parameter is not valid
 409          * @throws      BadMethodCallException  If the stack is empty
 410          */
 411         protected function popLast (string $stackerName) {
 412                 // Validate parameter
 413                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
 414                 if (empty($stackerName)) {
 415                         // No empty stack name
 416                         throw new InvalidArgumentException('Parameter "stackerName" is empty');
 417                 } elseif ($this->isStackEmpty($stackerName)) {
 418                         // Throw an exception
 419                         throw new BadMethodCallException([$this, $stackerName], self::EXCEPTION_STACKER_IS_EMPTY);
 420                 }
 421
 422                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 423                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 424                 return NULL;
 425         }
 426
 427         /**
 428          * "Pops" first entry from stack
 429          *
 430          * @param       $stackerName    Name of the stack
 431          * @return      $value                  Value "shifted" from array
 432          * @throws      InvalidArgumentException        If a parameter is not valid
 433          * @throws      BadMethodCallException  If the named stacker is empty
 434          */
 435         protected function popFirst (string $stackerName) {
 436                 // Validate parameter
 437                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
 438                 if (empty($stackerName)) {
 439                         // No empty stack name
 440                         throw new InvalidArgumentException('Parameter "stackerName" is empty');
 441                 } elseif ($this->isStackEmpty($stackerName)) {
 442                         // Throw an exception
 443                         throw new BadMethodCallException([$this, $stackerName], self::EXCEPTION_STACKER_IS_EMPTY);
 444                 }
 445
 446                 // Now, remove the last entry, we don't care about the return value here, see elseif() block above
 447                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 448                 return NULL;
 449         }
 450
 451         /**
 452          * Checks whether the given stack is full
 453          *
 454          * @param       $stackerName    Name of the stack
 455          * @return      $isFull                 Whether the stack is full
 456          * @throws      InvalidArgumentException        If a parameter is not valid
 457          */
 458         protected function isStackFull (string $stackerName) {
 459                 // Validate parameter
 460                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
 461                 if (empty($stackerName)) {
 462                         // No empty stack name
 463                         throw new InvalidArgumentException('Parameter "stackerName" is empty');
 464                 }
 465
 466                 // @TODO Please implement this, returning false
 467                 /* NOISY-DEBUG: */ $this->partialStub('[' . __METHOD__ . ':' . __LINE__ . '] stackerName=' . $stackerName);
 468                 $isFull = false;
 469
 470                 // Return result
 471                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: isFull=%d - EXIT!', intval($isFull)));
 472                 return $isFull;
 473         }
 474
 475         /**
 476          * Checks whether the given stack is empty
 477          *
 478          * @param       $stackerName            Name of the stack
 479          * @return      $isEmpty                        Whether the stack is empty
 480          * @throws      InvalidArgumentException        If a parameter is not valid
 481          * @throws      BadMethodCallException  If given stack is missing
 482          */
 483         public function isStackEmpty (string $stackerName) {
 484                 // Validate parameter
 485                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
 486                 if (empty($stackerName)) {
 487                         // No empty stack name
 488                         throw new InvalidArgumentException('Parameter "stackerName" is empty');
 489                 }
 490
 491                 // So, is the stack empty?
 492                 $isEmpty = (($this->getStackCount($stackerName)) == 0);
 493
 494                 // Return result
 495                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: isEmpty=%d - EXIT!', intval($isEmpty)));
 496                 return $isEmpty;
 497         }
 498
 499         /**
 500          * Checks whether the given stack is initialized (set in array $stackers)
 501          *
 502          * @param       $stackerName    Name of the stack
 503          * @return      $isInitialized  Whether the stack is initialized
 504          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 505          */
 506         public function isStackInitialized (string $stackerName) {
 507                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getBinaryFileInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 508         }
 509
 510         /**
 511          * Determines whether the EOF has been reached
 512          *
 513          * @return      $isEndOfFileReached             Whether the EOF has been reached
 514          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 515          */
 516         public function isEndOfFileReached () {
 517                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getBinaryFileInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 518         }
 519
 520         /**
 521          * Getter for size of given stack (array count)
 522          *
 523          * @param       $stackerName    Name of the stack
 524          * @return      $count                  Size of stack (array count)
 525          */
 526         public function getStackCount (string $stackerName) {
 527                 // Now, simply return the found count value, this must be up-to-date then!
 528                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackerName=%s - CALLED!', $stackerName));
 529                 $count = $this->getIteratorInstance()->getBinaryFileInstance()->getCounter();
 530
 531                 // Return count
 532                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: count=%d - EXIT!', $count));
 533                 return $count;
 534         }
 535
 536         /**
 537          * Calculates minimum length for one entry/block
 538          *
 539          * @return      $length         Minimum length for one entry/block
 540          */
 541         public function calculateMinimumBlockLength () {
 542                 // Is the value "cached"?
 543                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: CALLED!');
 544                 if (self::$minimumBlockLength == 0) {
 545                         // Calulcate it
 546                         //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: Calculating ...');
 547                         self::$minimumBlockLength =
 548                                 // Length of entry group
 549                                 BinaryFile::LENGTH_GROUP + strlen(chr(BinaryFile::SEPARATOR_GROUP_HASH)) +
 550                                 // Hash + value
 551                                 self::getHashLength() + strlen(chr(BinaryFile::SEPARATOR_HASH_VALUE)) + 1 +
 552                                 // Final separator
 553                                 strlen(chr(BinaryFile::SEPARATOR_ENTRIES));
 554                 }
 555
 556                 // Return it
 557                 //* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: self::minimumBlockLength=%d - EXIT!', self::$minimumBlockLength));
 558                 return self::$minimumBlockLength;
 559         }
 560
 561         /**
 562          * Initializes counter for valid entries, arrays for damaged entries and
 563          * an array for gap seek positions. If you call this method on your own,
 564          * please re-analyze the file structure. So you are better to call
 565          * analyzeFileStructure() instead of this method.
 566          *
 567          * @return      void
 568          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 569          */
 570         public function initCountersGapsArray () {
 571                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getBinaryFileInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 572         }
 573
 574         /**
 575          * Getter for header size
 576          *
 577          * @return      $totalEntries   Size of file header
 578          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 579          */
 580         public final function getHeaderSize () {
 581                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getBinaryFileInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 582         }
 583
 584         /**
 585          * Setter for header size
 586          *
 587          * @param       $headerSize             Size of file header
 588          * @return      void
 589          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 590          */
 591         public final function setHeaderSize (int $headerSize) {
 592                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getBinaryFileInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 593         }
 594
 595         /**
 596          * Getter for header array
 597          *
 598          * @return      $totalEntries   Size of file header
 599          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 600          */
 601         public final function getHeader () {
 602                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getBinaryFileInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 603         }
 604
 605         /**
 606          * Setter for header
 607          *
 608          * @param       $header         Array for a file header
 609          * @return      void
 610          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 611          */
 612         public final function setHeader (array $header) {
 613                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getBinaryFileInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 614         }
 615
 616         /**
 617          * Updates seekPosition attribute from file to avoid to much access on file.
 618          *
 619          * @return      void
 620          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 621          */
 622         public function updateSeekPosition () {
 623                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getBinaryFileInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 624         }
 625
 626         /**
 627          * Getter for total entries
 628          *
 629          * @return      $totalEntries   Total entries in this file
 630          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 631          */
 632         public final function getCounter () {
 633                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getBinaryFileInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 634         }
 635
 636         /**
 637          * Writes data at given position
 638          *
 639          * @param       $seekPosition   Seek position
 640          * @param       $data                   Data to be written
 641          * @param       $flushHeader    Whether to flush the header (default: flush)
 642          * @return      void
 643          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 644          */
 645         public function writeData (int $seekPosition, string $data, bool $flushHeader = true) {
 646                 // Not supported
 647                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getBinaryFileInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 648         }
 649
 650         /**
 651          * Writes at given position by seeking to it.
 652          *
 653          * @param       $seekPosition   Seek position in file
 654          * @param       $dataStream             Data to be written
 655          * @return      mixed                   Number of writes bytes or false on error
 656          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 657          */
 658         public function writeAtPosition (int $seekPosition, string $dataStream) {
 659                 // Not supported
 660                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getBinaryFileInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 661         }
 662
 663         /**
 664          * Writes given value to the file and returns a hash and gap position for it
 665          *
 666          * @param       $stackName      Group identifier
 667          * @param       $value          Value to be added to the stack
 668          * @return      $data           Hash and gap position
 669          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 670          */
 671         public function writeValueToFile (string $stackName, $value) {
 672                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getBinaryFileInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 673         }
 674
 675         /**
 676          * Searches for next suitable gap the given length of data can fit in
 677          * including padding bytes.
 678          *
 679          * @param       $length                 Length of raw data
 680          * @return      $seekPosition   Found next gap's seek position
 681          * @throws      UnsupportedOperationException   This method is not (and maybe never will be) supported
 682          */
 683         public function searchNextGap (int $length) {
 684                 // Not supported here
 685                 throw new UnsupportedOperationException(array($this, __FUNCTION__, $this->getIteratorInstance()->getBinaryFileInstance()), self::EXCEPTION_UNSPPORTED_OPERATION);
 686         }
 687
 688         /**
 689          * "Getter" for file size
 690          *
 691          * @return      $fileSize       Size of currently loaded file
 692          */
 693         public function getFileSize () {
 694                 // Call iterator's method
 695                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput('BASE-FILE-STACK: CALLED!');
 696                 $size = $this->getIteratorInstance()->getBinaryFileInstance()->getFileSize();
 697
 698                 // Return size
 699                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: size=%d - EXIT!', $size));
 700                 return $size;
 701         }
 702
 703         /**
 704          * Writes given raw data to the file and returns a gap position and length
 705          *
 706          * @param       $stackName      Group identifier
 707          * @param       $hash           Hash from encoded value
 708          * @param       $encoded        Encoded value to be written to the file
 709          * @return      $data           Gap position and length of the raw data
 710          */
 711         public function writeDataToFreeGap (string $stackName, string $hash, string $encoded) {
 712                 // Raw data been written to the file
 713                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackName=%s,hash=%s,encoded()=%d - CALLED!', $stackName, $hash, strlen($encoded)));
 714                 $rawData = sprintf('%s%s%s%s%s',
 715                         $stackName,
 716                         BinaryFile::SEPARATOR_GROUP_HASH,
 717                         hex2bin($hash),
 718                         BinaryFile::SEPARATOR_HASH_VALUE,
 719                         $encoded
 720                 );
 721
 722                 // Search for next free gap
 723                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackName=%s,hash=%s,rawData()=%d', $stackName, $hash, strlen($rawData)));
 724                 $gapPosition = $this->getIteratorInstance()->getBinaryFileInstance()->searchNextGap(strlen($rawData));
 725
 726                 // Gap position cannot be smaller than header length + 1
 727                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: gapPosition=%d', $gapPosition));
 728                 if ($gapPosition <= $this->getIteratorInstance()->getBinaryFileInstance()->getHeaderSize()) {
 729                         // Improper gap position
 730                         throw new UnexpectedValueException(sprintf('gapPosition[%s]=%d is not larger than headerSize=%d',
 731                                 gettype($gapPosition),
 732                                 $gapPosition,
 733                                 $this->getIteratorInstance()->getBinaryFileInstance()->getHeaderSize()
 734                         ));
 735                 }
 736
 737                 // Then write the data at that gap
 738                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackName=%s,hash=%s,gapPosition=%s', $stackName, $hash, $gapPosition));
 739                 $this->getIteratorInstance()->getBinaryFileInstance()->writeData($gapPosition, $rawData);
 740
 741                 // Return gap position, hash and length of raw data
 742                 /* NOISY-DEBUG: */ self::createDebugInstance(__CLASS__, __LINE__)->debugOutput(sprintf('BASE-FILE-STACK: stackName=%s,hash=%s,rawData()=%d - EXIT!', $stackName, $hash, strlen($rawData)));
 743                 return [
 744                         StackableFile::ARRAY_NAME_GAP_POSITION => $gapPosition,
 745                         StackableFile::ARRAY_NAME_HASH         => $hash,
 746                         StackableFile::ARRAY_NAME_DATA_LENGTH  => strlen($rawData),
 747                 ];
 748         }
 749
 750 }