smalot /
pdfparser
| Total Complexity | 213 |
| Total Lines | 929 |
| Duplicated Lines | 0 % |
| Changes | 12 | ||
| Bugs | 2 | Features | 1 |
Complex classes like RawDataParser often do a lot of different things. To break such a class down, we need to identify a cohesive component within that class. A common approach to find such a component is to look for fields/methods that share the same prefixes, or suffixes.
Once you have determined the fields that belong together, you can apply the Extract Class refactoring. If the component makes sense as a sub-class, Extract Subclass is also a candidate, and is often faster.
While breaking up the class, it is a good idea to analyze how other classes use RawDataParser, and based on these observations, apply Extract Interface, too.
| 1 | <?php |
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| 49 | class RawDataParser |
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| 50 | { |
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| 51 | /** |
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| 52 | * @var Config |
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| 53 | */ |
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| 54 | private $config; |
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| 55 | |||
| 56 | /** |
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| 57 | * Configuration array. |
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| 58 | * |
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| 59 | * @var array<string,bool> |
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| 60 | */ |
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| 61 | protected $cfg = [ |
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| 62 | // if `true` ignore filter decoding errors |
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| 63 | 'ignore_filter_decoding_errors' => true, |
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| 64 | // if `true` ignore missing filter decoding errors |
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| 65 | 'ignore_missing_filter_decoders' => true, |
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| 66 | ]; |
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| 67 | |||
| 68 | protected $filterHelper; |
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| 69 | protected $objects; |
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| 70 | |||
| 71 | /** |
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| 72 | * @param array $cfg Configuration array, default is [] |
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| 73 | */ |
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| 74 | public function __construct($cfg = [], ?Config $config = null) |
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| 75 | { |
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| 76 | // merge given array with default values |
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| 77 | $this->cfg = array_merge($this->cfg, $cfg); |
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| 78 | |||
| 79 | $this->filterHelper = new FilterHelper(); |
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| 80 | $this->config = $config ?: new Config(); |
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| 81 | } |
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| 82 | |||
| 83 | /** |
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| 84 | * Decode the specified stream. |
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| 85 | * |
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| 86 | * @param string $pdfData PDF data |
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| 87 | * @param array $sdic Stream's dictionary array |
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| 88 | * @param string $stream Stream to decode |
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| 89 | * |
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| 90 | * @return array containing decoded stream data and remaining filters |
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| 91 | * |
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| 92 | * @throws \Exception |
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| 93 | */ |
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| 94 | protected function decodeStream(string $pdfData, array $xref, array $sdic, string $stream): array |
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| 95 | { |
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| 96 | // get stream length and filters |
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| 97 | $slength = \strlen($stream); |
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| 98 | if ($slength <= 0) { |
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| 99 | return ['', []]; |
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| 100 | } |
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| 101 | $filters = []; |
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| 102 | foreach ($sdic as $k => $v) { |
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| 103 | if ('/' == $v[0]) { |
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| 104 | if (('Length' == $v[1]) && (isset($sdic[$k + 1])) && ('numeric' == $sdic[$k + 1][0])) { |
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| 105 | // get declared stream length |
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| 106 | $declength = (int) $sdic[$k + 1][1]; |
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| 107 | if ($declength < $slength) { |
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| 108 | $stream = substr($stream, 0, $declength); |
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| 109 | $slength = $declength; |
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| 110 | } |
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| 111 | } elseif (('Filter' == $v[1]) && (isset($sdic[$k + 1]))) { |
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| 112 | // resolve indirect object |
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| 113 | $objval = $this->getObjectVal($pdfData, $xref, $sdic[$k + 1]); |
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| 114 | if ('/' == $objval[0]) { |
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| 115 | // single filter |
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| 116 | $filters[] = $objval[1]; |
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| 117 | } elseif ('[' == $objval[0]) { |
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| 118 | // array of filters |
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| 119 | foreach ($objval[1] as $flt) { |
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| 120 | if ('/' == $flt[0]) { |
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| 121 | $filters[] = $flt[1]; |
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| 122 | } |
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| 123 | } |
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| 124 | } |
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| 125 | } |
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| 126 | } |
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| 127 | } |
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| 128 | |||
| 129 | // decode the stream |
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| 130 | $remaining_filters = []; |
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| 131 | foreach ($filters as $filter) { |
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| 132 | if (\in_array($filter, $this->filterHelper->getAvailableFilters(), true)) { |
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| 133 | try { |
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| 134 | $stream = $this->filterHelper->decodeFilter($filter, $stream, $this->config->getDecodeMemoryLimit()); |
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| 135 | } catch (\Exception $e) { |
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| 136 | $emsg = $e->getMessage(); |
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| 137 | if ((('~' == $emsg[0]) && !$this->cfg['ignore_missing_filter_decoders']) |
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| 138 | || (('~' != $emsg[0]) && !$this->cfg['ignore_filter_decoding_errors']) |
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| 139 | ) { |
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| 140 | throw new \Exception($e->getMessage()); |
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| 141 | } |
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| 142 | } |
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| 143 | } else { |
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| 144 | // add missing filter to array |
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| 145 | $remaining_filters[] = $filter; |
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| 146 | } |
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| 147 | } |
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| 148 | |||
| 149 | return [$stream, $remaining_filters]; |
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| 150 | } |
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| 151 | |||
| 152 | /** |
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| 153 | * Decode the Cross-Reference section |
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| 154 | * |
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| 155 | * @param string $pdfData PDF data |
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| 156 | * @param int $startxref Offset at which the xref section starts (position of the 'xref' keyword) |
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| 157 | * @param array $xref Previous xref array (if any) |
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| 158 | * |
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| 159 | * @return array containing xref and trailer data |
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| 160 | * |
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| 161 | * @throws \Exception |
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| 162 | */ |
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| 163 | protected function decodeXref(string $pdfData, int $startxref, array $xref = []): array |
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| 164 | { |
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| 165 | $startxref += 4; // 4 is the length of the word 'xref' |
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| 166 | // skip initial white space chars |
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| 167 | $offset = $startxref + strspn($pdfData, $this->config->getPdfWhitespaces(), $startxref); |
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| 168 | // initialize object number |
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| 169 | $obj_num = 0; |
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| 170 | // search for cross-reference entries or subsection |
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| 171 | while (preg_match('/([0-9]+)[\x20]([0-9]+)[\x20]?([nf]?)(\r\n|[\x20]?[\r\n])/', $pdfData, $matches, \PREG_OFFSET_CAPTURE, $offset) > 0) { |
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| 172 | if ($matches[0][1] != $offset) { |
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| 173 | // we are on another section |
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| 174 | break; |
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| 175 | } |
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| 176 | $offset += \strlen($matches[0][0]); |
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| 177 | if ('n' == $matches[3][0]) { |
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| 178 | // create unique object index: [object number]_[generation number] |
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| 179 | $index = $obj_num.'_'.(int) $matches[2][0]; |
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| 180 | // check if object already exist |
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| 181 | if (!isset($xref['xref'][$index])) { |
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| 182 | // store object offset position |
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| 183 | $xref['xref'][$index] = (int) $matches[1][0]; |
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| 184 | } |
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| 185 | ++$obj_num; |
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| 186 | } elseif ('f' == $matches[3][0]) { |
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| 187 | ++$obj_num; |
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| 188 | } else { |
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| 189 | // object number (index) |
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| 190 | $obj_num = (int) $matches[1][0]; |
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| 191 | } |
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| 192 | } |
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| 193 | // get trailer data |
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| 194 | if (preg_match('/trailer[\s]*<<(.*)>>/isU', $pdfData, $matches, \PREG_OFFSET_CAPTURE, $offset) > 0) { |
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| 195 | $trailer_data = $matches[1][0]; |
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| 196 | if (!isset($xref['trailer']) || empty($xref['trailer'])) { |
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| 197 | // get only the last updated version |
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| 198 | $xref['trailer'] = []; |
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| 199 | // parse trailer_data |
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| 200 | if (preg_match('/Size[\s]+([0-9]+)/i', $trailer_data, $matches) > 0) { |
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| 201 | $xref['trailer']['size'] = (int) $matches[1]; |
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| 202 | } |
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| 203 | if (preg_match('/Root[\s]+([0-9]+)[\s]+([0-9]+)[\s]+R/i', $trailer_data, $matches) > 0) { |
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| 204 | $xref['trailer']['root'] = (int) $matches[1].'_'.(int) $matches[2]; |
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| 205 | } |
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| 206 | if (preg_match('/Encrypt[\s]+([0-9]+)[\s]+([0-9]+)[\s]+R/i', $trailer_data, $matches) > 0) { |
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| 207 | $xref['trailer']['encrypt'] = (int) $matches[1].'_'.(int) $matches[2]; |
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| 208 | } |
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| 209 | if (preg_match('/Info[\s]+([0-9]+)[\s]+([0-9]+)[\s]+R/i', $trailer_data, $matches) > 0) { |
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| 210 | $xref['trailer']['info'] = (int) $matches[1].'_'.(int) $matches[2]; |
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| 211 | } |
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| 212 | if (preg_match('/ID[\s]*[\[][\s]*[<]([^>]*)[>][\s]*[<]([^>]*)[>]/i', $trailer_data, $matches) > 0) { |
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| 213 | $xref['trailer']['id'] = []; |
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| 214 | $xref['trailer']['id'][0] = $matches[1]; |
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| 215 | $xref['trailer']['id'][1] = $matches[2]; |
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| 216 | } |
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| 217 | } |
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| 218 | if (preg_match('/Prev[\s]+([0-9]+)/i', $trailer_data, $matches) > 0) { |
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| 219 | $offset = (int) $matches[1]; |
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| 220 | if (0 != $offset) { |
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| 221 | // get previous xref |
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| 222 | $xref = $this->getXrefData($pdfData, $offset, $xref); |
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| 223 | } |
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| 224 | } |
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| 225 | } else { |
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| 226 | throw new \Exception('Unable to find trailer'); |
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| 227 | } |
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| 228 | |||
| 229 | return $xref; |
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| 230 | } |
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| 231 | |||
| 232 | /** |
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| 233 | * Decode the Cross-Reference Stream section |
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| 234 | * |
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| 235 | * @param string $pdfData PDF data |
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| 236 | * @param int $startxref Offset at which the xref section starts |
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| 237 | * @param array $xref Previous xref array (if any) |
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| 238 | * |
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| 239 | * @return array containing xref and trailer data |
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| 240 | * |
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| 241 | * @throws \Exception if unknown PNG predictor detected |
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| 242 | */ |
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| 243 | protected function decodeXrefStream(string $pdfData, int $startxref, array $xref = []): array |
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| 244 | { |
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| 245 | // try to read Cross-Reference Stream |
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| 246 | $xrefobj = $this->getRawObject($pdfData, $startxref); |
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| 247 | $xrefcrs = $this->getIndirectObject($pdfData, $xref, $xrefobj[1], $startxref, true); |
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| 248 | if (!isset($xref['trailer']) || empty($xref['trailer'])) { |
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| 249 | // get only the last updated version |
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| 250 | $xref['trailer'] = []; |
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| 251 | $filltrailer = true; |
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| 252 | } else { |
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| 253 | $filltrailer = false; |
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| 254 | } |
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| 255 | if (!isset($xref['xref'])) { |
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| 256 | $xref['xref'] = []; |
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| 257 | } |
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| 258 | $valid_crs = false; |
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| 259 | $columns = 0; |
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| 260 | $predictor = null; |
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| 261 | $sarr = $xrefcrs[0][1]; |
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| 262 | if (!\is_array($sarr)) { |
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| 263 | $sarr = []; |
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| 264 | } |
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| 265 | |||
| 266 | $wb = []; |
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| 267 | |||
| 268 | foreach ($sarr as $k => $v) { |
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| 269 | if ( |
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| 270 | ('/' == $v[0]) |
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| 271 | && ('Type' == $v[1]) |
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| 272 | && ( |
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| 273 | isset($sarr[$k + 1]) |
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| 274 | && '/' == $sarr[$k + 1][0] |
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| 275 | && 'XRef' == $sarr[$k + 1][1] |
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| 276 | ) |
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| 277 | ) { |
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| 278 | $valid_crs = true; |
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| 279 | } elseif (('/' == $v[0]) && ('Index' == $v[1]) && (isset($sarr[$k + 1]))) { |
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| 280 | // initialize list for: first object number in the subsection / number of objects |
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| 281 | $index_blocks = []; |
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| 282 | for ($m = 0; $m < \count($sarr[$k + 1][1]); $m += 2) { |
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| 283 | $index_blocks[] = [$sarr[$k + 1][1][$m][1], $sarr[$k + 1][1][$m + 1][1]]; |
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| 284 | } |
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| 285 | } elseif (('/' == $v[0]) && ('Prev' == $v[1]) && (isset($sarr[$k + 1]) && ('numeric' == $sarr[$k + 1][0]))) { |
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| 286 | // get previous xref offset |
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| 287 | $prevxref = (int) $sarr[$k + 1][1]; |
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| 288 | } elseif (('/' == $v[0]) && ('W' == $v[1]) && (isset($sarr[$k + 1]))) { |
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| 289 | // number of bytes (in the decoded stream) of the corresponding field |
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| 290 | $wb[0] = (int) $sarr[$k + 1][1][0][1]; |
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| 291 | $wb[1] = (int) $sarr[$k + 1][1][1][1]; |
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| 292 | $wb[2] = (int) $sarr[$k + 1][1][2][1]; |
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| 293 | } elseif (('/' == $v[0]) && ('DecodeParms' == $v[1]) && (isset($sarr[$k + 1][1]))) { |
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| 294 | $decpar = $sarr[$k + 1][1]; |
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| 295 | foreach ($decpar as $kdc => $vdc) { |
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| 296 | if ( |
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| 297 | '/' == $vdc[0] |
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| 298 | && 'Columns' == $vdc[1] |
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| 299 | && ( |
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| 300 | isset($decpar[$kdc + 1]) |
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| 301 | && 'numeric' == $decpar[$kdc + 1][0] |
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| 302 | ) |
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| 303 | ) { |
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| 304 | $columns = (int) $decpar[$kdc + 1][1]; |
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| 305 | } elseif ( |
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| 306 | '/' == $vdc[0] |
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| 307 | && 'Predictor' == $vdc[1] |
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| 308 | && ( |
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| 309 | isset($decpar[$kdc + 1]) |
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| 310 | && 'numeric' == $decpar[$kdc + 1][0] |
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| 311 | ) |
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| 312 | ) { |
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| 313 | $predictor = (int) $decpar[$kdc + 1][1]; |
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| 314 | } |
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| 315 | } |
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| 316 | } elseif ($filltrailer) { |
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| 317 | if (('/' == $v[0]) && ('Size' == $v[1]) && (isset($sarr[$k + 1]) && ('numeric' == $sarr[$k + 1][0]))) { |
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| 318 | $xref['trailer']['size'] = $sarr[$k + 1][1]; |
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| 319 | } elseif (('/' == $v[0]) && ('Root' == $v[1]) && (isset($sarr[$k + 1]) && ('objref' == $sarr[$k + 1][0]))) { |
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| 320 | $xref['trailer']['root'] = $sarr[$k + 1][1]; |
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| 321 | } elseif (('/' == $v[0]) && ('Info' == $v[1]) && (isset($sarr[$k + 1]) && ('objref' == $sarr[$k + 1][0]))) { |
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| 322 | $xref['trailer']['info'] = $sarr[$k + 1][1]; |
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| 323 | } elseif (('/' == $v[0]) && ('Encrypt' == $v[1]) && (isset($sarr[$k + 1]) && ('objref' == $sarr[$k + 1][0]))) { |
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| 324 | $xref['trailer']['encrypt'] = $sarr[$k + 1][1]; |
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| 325 | } elseif (('/' == $v[0]) && ('ID' == $v[1]) && (isset($sarr[$k + 1]))) { |
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| 326 | $xref['trailer']['id'] = []; |
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| 327 | $xref['trailer']['id'][0] = $sarr[$k + 1][1][0][1]; |
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| 328 | $xref['trailer']['id'][1] = $sarr[$k + 1][1][1][1]; |
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| 329 | } |
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| 330 | } |
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| 331 | } |
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| 332 | |||
| 333 | // decode data |
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| 334 | if ($valid_crs && isset($xrefcrs[1][3][0])) { |
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| 335 | if (null !== $predictor) { |
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| 336 | // number of bytes in a row |
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| 337 | $rowlen = ($columns + 1); |
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| 338 | // convert the stream into an array of integers |
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| 339 | /** @var array<int> */ |
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| 340 | $sdata = unpack('C*', $xrefcrs[1][3][0]); |
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| 341 | // TODO: Handle the case when unpack returns false |
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| 342 | |||
| 343 | // split the rows |
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| 344 | $sdata = array_chunk($sdata, $rowlen); |
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| 345 | |||
| 346 | // initialize decoded array |
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| 347 | $ddata = []; |
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| 348 | // initialize first row with zeros |
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| 349 | $prev_row = array_fill(0, $rowlen, 0); |
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| 350 | // for each row apply PNG unpredictor |
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| 351 | foreach ($sdata as $k => $row) { |
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| 352 | // initialize new row |
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| 353 | $ddata[$k] = []; |
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| 354 | // get PNG predictor value |
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| 355 | $predictor = (10 + $row[0]); |
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| 356 | // for each byte on the row |
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| 357 | for ($i = 1; $i <= $columns; ++$i) { |
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| 358 | // new index |
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| 359 | $j = ($i - 1); |
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| 360 | $row_up = $prev_row[$j]; |
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| 361 | if (1 == $i) { |
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| 362 | $row_left = 0; |
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| 363 | $row_upleft = 0; |
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| 364 | } else { |
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| 365 | $row_left = $row[$i - 1]; |
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| 366 | $row_upleft = $prev_row[$j - 1]; |
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| 367 | } |
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| 368 | switch ($predictor) { |
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| 369 | case 10: // PNG prediction (on encoding, PNG None on all rows) |
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| 370 | $ddata[$k][$j] = $row[$i]; |
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| 371 | break; |
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| 372 | |||
| 373 | case 11: // PNG prediction (on encoding, PNG Sub on all rows) |
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| 374 | $ddata[$k][$j] = (($row[$i] + $row_left) & 0xFF); |
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| 375 | break; |
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| 376 | |||
| 377 | case 12: // PNG prediction (on encoding, PNG Up on all rows) |
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| 378 | $ddata[$k][$j] = (($row[$i] + $row_up) & 0xFF); |
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| 379 | break; |
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| 380 | |||
| 381 | case 13: // PNG prediction (on encoding, PNG Average on all rows) |
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| 382 | $ddata[$k][$j] = (($row[$i] + (($row_left + $row_up) / 2)) & 0xFF); |
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| 383 | break; |
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| 384 | |||
| 385 | case 14: // PNG prediction (on encoding, PNG Paeth on all rows) |
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| 386 | // initial estimate |
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| 387 | $p = ($row_left + $row_up - $row_upleft); |
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| 388 | // distances |
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| 389 | $pa = abs($p - $row_left); |
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| 390 | $pb = abs($p - $row_up); |
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| 391 | $pc = abs($p - $row_upleft); |
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| 392 | $pmin = min($pa, $pb, $pc); |
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| 393 | // return minimum distance |
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| 394 | switch ($pmin) { |
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| 395 | case $pa: |
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| 396 | $ddata[$k][$j] = (($row[$i] + $row_left) & 0xFF); |
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| 397 | break; |
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| 398 | |||
| 399 | case $pb: |
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| 400 | $ddata[$k][$j] = (($row[$i] + $row_up) & 0xFF); |
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| 401 | break; |
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| 402 | |||
| 403 | case $pc: |
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| 404 | $ddata[$k][$j] = (($row[$i] + $row_upleft) & 0xFF); |
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| 405 | break; |
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| 406 | } |
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| 407 | break; |
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| 408 | |||
| 409 | default: // PNG prediction (on encoding, PNG optimum) |
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| 410 | throw new \Exception('Unknown PNG predictor: '.$predictor); |
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| 411 | } |
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| 412 | } |
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| 413 | $prev_row = $ddata[$k]; |
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| 414 | } // end for each row |
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| 415 | // complete decoding |
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| 416 | } else { |
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| 417 | // number of bytes in a row |
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| 418 | $rowlen = array_sum($wb); |
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| 419 | if (0 < $rowlen) { |
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| 420 | // convert the stream into an array of integers |
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| 421 | $sdata = unpack('C*', $xrefcrs[1][3][0]); |
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| 422 | // split the rows |
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| 423 | $ddata = array_chunk($sdata, $rowlen); |
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| 424 | } else { |
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| 425 | // if the row length is zero, $ddata should be an empty array as well |
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| 426 | $ddata = []; |
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| 427 | } |
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| 428 | } |
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| 429 | |||
| 430 | $sdata = []; |
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| 431 | |||
| 432 | // for every row |
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| 433 | foreach ($ddata as $k => $row) { |
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| 434 | // initialize new row |
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| 435 | $sdata[$k] = [0, 0, 0]; |
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| 436 | if (0 == $wb[0]) { |
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| 437 | // default type field |
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| 438 | $sdata[$k][0] = 1; |
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| 439 | } |
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| 440 | $i = 0; // count bytes in the row |
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| 441 | // for every column |
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| 442 | for ($c = 0; $c < 3; ++$c) { |
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| 443 | // for every byte on the column |
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| 444 | for ($b = 0; $b < $wb[$c]; ++$b) { |
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| 445 | if (isset($row[$i])) { |
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| 446 | $sdata[$k][$c] += ($row[$i] << (($wb[$c] - 1 - $b) * 8)); |
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| 447 | } |
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| 448 | ++$i; |
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| 449 | } |
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| 450 | } |
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| 451 | } |
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| 452 | |||
| 453 | // fill xref |
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| 454 | if (isset($index_blocks)) { |
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| 455 | // load the first object number of the first /Index entry |
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| 456 | $obj_num = $index_blocks[0][0]; |
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| 457 | } else { |
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| 458 | $obj_num = 0; |
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| 459 | } |
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| 460 | foreach ($sdata as $k => $row) { |
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| 461 | switch ($row[0]) { |
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| 462 | case 0: // (f) linked list of free objects |
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| 463 | break; |
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| 464 | |||
| 465 | case 1: // (n) objects that are in use but are not compressed |
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| 466 | // create unique object index: [object number]_[generation number] |
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| 467 | $index = $obj_num.'_'.$row[2]; |
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| 468 | // check if object already exist |
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| 469 | if (!isset($xref['xref'][$index])) { |
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| 470 | // store object offset position |
||
| 471 | $xref['xref'][$index] = $row[1]; |
||
| 472 | } |
||
| 473 | break; |
||
| 474 | |||
| 475 | case 2: // compressed objects |
||
| 476 | // $row[1] = object number of the object stream in which this object is stored |
||
| 477 | // $row[2] = index of this object within the object stream |
||
| 478 | $index = $row[1].'_0_'.$row[2]; |
||
| 479 | $xref['xref'][$index] = -1; |
||
| 480 | break; |
||
| 481 | |||
| 482 | default: // null objects |
||
| 483 | break; |
||
| 484 | } |
||
| 485 | ++$obj_num; |
||
| 486 | if (isset($index_blocks)) { |
||
| 487 | // reduce the number of remaining objects |
||
| 488 | --$index_blocks[0][1]; |
||
| 489 | if (0 == $index_blocks[0][1]) { |
||
| 490 | // remove the actual used /Index entry |
||
| 491 | array_shift($index_blocks); |
||
| 492 | if (0 < \count($index_blocks)) { |
||
| 493 | // load the first object number of the following /Index entry |
||
| 494 | $obj_num = $index_blocks[0][0]; |
||
| 495 | } else { |
||
| 496 | // if there are no more entries, remove $index_blocks to avoid actions on an empty array |
||
| 497 | unset($index_blocks); |
||
| 498 | } |
||
| 499 | } |
||
| 500 | } |
||
| 501 | } |
||
| 502 | } // end decoding data |
||
| 503 | if (isset($prevxref)) { |
||
| 504 | // get previous xref |
||
| 505 | $xref = $this->getXrefData($pdfData, $prevxref, $xref); |
||
| 506 | } |
||
| 507 | |||
| 508 | return $xref; |
||
| 509 | } |
||
| 510 | |||
| 511 | protected function getObjectHeaderPattern(array $objRefs): string |
||
| 512 | { |
||
| 513 | // consider all whitespace character (PDF specifications) |
||
| 514 | return '/'.$objRefs[0].$this->config->getPdfWhitespacesRegex().$objRefs[1].$this->config->getPdfWhitespacesRegex().'obj/'; |
||
| 515 | } |
||
| 516 | |||
| 517 | protected function getObjectHeaderLen(array $objRefs): int |
||
| 522 | } |
||
| 523 | |||
| 524 | /** |
||
| 525 | * Get content of indirect object. |
||
| 526 | * |
||
| 527 | * @param string $pdfData PDF data |
||
| 528 | * @param string $objRef Object number and generation number separated by underscore character |
||
| 529 | * @param int $offset Object offset |
||
| 530 | * @param bool $decoding If true decode streams |
||
| 531 | * |
||
| 532 | * @return array containing object data |
||
| 533 | * |
||
| 534 | * @throws \Exception if invalid object reference found |
||
| 535 | */ |
||
| 536 | protected function getIndirectObject(string $pdfData, array $xref, string $objRef, int $offset = 0, bool $decoding = true): array |
||
| 537 | { |
||
| 538 | /* |
||
| 539 | * build indirect object header |
||
| 540 | */ |
||
| 541 | // $objHeader = "[object number] [generation number] obj" |
||
| 542 | $objRefArr = explode('_', $objRef); |
||
| 543 | if (2 !== \count($objRefArr)) { |
||
| 544 | throw new \Exception('Invalid object reference for $obj.'); |
||
| 545 | } |
||
| 546 | |||
| 547 | $objHeaderLen = $this->getObjectHeaderLen($objRefArr); |
||
| 548 | |||
| 549 | /* |
||
| 550 | * check if we are in position |
||
| 551 | */ |
||
| 552 | // ignore whitespace characters at offset |
||
| 553 | $offset += strspn($pdfData, $this->config->getPdfWhitespaces(), $offset); |
||
| 554 | // ignore leading zeros for object number |
||
| 555 | $offset += strspn($pdfData, '0', $offset); |
||
| 556 | if (0 == preg_match($this->getObjectHeaderPattern($objRefArr), substr($pdfData, $offset, $objHeaderLen))) { |
||
| 557 | // an indirect reference to an undefined object shall be considered a reference to the null object |
||
| 558 | return ['null', 'null', $offset]; |
||
| 559 | } |
||
| 560 | |||
| 561 | /* |
||
| 562 | * get content |
||
| 563 | */ |
||
| 564 | // starting position of object content |
||
| 565 | $offset += $objHeaderLen; |
||
| 566 | $objContentArr = []; |
||
| 567 | $i = 0; // object main index |
||
| 568 | $header = null; |
||
| 569 | do { |
||
| 570 | $oldOffset = $offset; |
||
| 571 | // get element |
||
| 572 | $element = $this->getRawObject($pdfData, $offset, null != $header ? $header[1] : null); |
||
| 573 | $offset = $element[2]; |
||
| 574 | // decode stream using stream's dictionary information |
||
| 575 | if ($decoding && ('stream' === $element[0]) && null != $header) { |
||
| 576 | $element[3] = $this->decodeStream($pdfData, $xref, $header[1], $element[1]); |
||
| 577 | } |
||
| 578 | $objContentArr[$i] = $element; |
||
| 579 | $header = isset($element[0]) && '<<' === $element[0] ? $element : null; |
||
| 580 | ++$i; |
||
| 581 | } while (('endobj' !== $element[0]) && ($offset !== $oldOffset)); |
||
| 582 | // remove closing delimiter |
||
| 583 | array_pop($objContentArr); |
||
| 584 | |||
| 585 | /* |
||
| 586 | * return raw object content |
||
| 587 | */ |
||
| 588 | return $objContentArr; |
||
| 589 | } |
||
| 590 | |||
| 591 | /** |
||
| 592 | * Get the content of object, resolving indirect object reference if necessary. |
||
| 593 | * |
||
| 594 | * @param string $pdfData PDF data |
||
| 595 | * @param array $obj Object value |
||
| 596 | * |
||
| 597 | * @return array containing object data |
||
| 598 | * |
||
| 599 | * @throws \Exception |
||
| 600 | */ |
||
| 601 | protected function getObjectVal(string $pdfData, $xref, array $obj): array |
||
| 602 | { |
||
| 603 | if ('objref' == $obj[0]) { |
||
| 604 | // reference to indirect object |
||
| 605 | if (isset($this->objects[$obj[1]])) { |
||
| 606 | // this object has been already parsed |
||
| 607 | return $this->objects[$obj[1]]; |
||
| 608 | } elseif (isset($xref[$obj[1]])) { |
||
| 609 | // parse new object |
||
| 610 | $this->objects[$obj[1]] = $this->getIndirectObject($pdfData, $xref, $obj[1], $xref[$obj[1]], false); |
||
| 611 | |||
| 612 | return $this->objects[$obj[1]]; |
||
| 613 | } |
||
| 614 | } |
||
| 615 | |||
| 616 | return $obj; |
||
| 617 | } |
||
| 618 | |||
| 619 | /** |
||
| 620 | * Get object type, raw value and offset to next object |
||
| 621 | * |
||
| 622 | * @param int $offset Object offset |
||
| 623 | * @param array|null $headerDic obj header's dictionary, parsed by getRawObject. Used for stream parsing optimization |
||
| 624 | * |
||
| 625 | * @return array containing object type, raw value and offset to next object |
||
| 626 | */ |
||
| 627 | protected function getRawObject(string $pdfData, int $offset = 0, ?array $headerDic = null): array |
||
| 818 | } |
||
| 819 | |||
| 820 | /** |
||
| 821 | * Get value of an object header's section (obj << YYY >> part ). |
||
| 822 | * |
||
| 823 | * It is similar to Header::get('...')->getContent(), the only difference is it can be used during the parsing process, |
||
| 824 | * when no Smalot\PdfParser\Header objects are created yet. |
||
| 825 | * |
||
| 826 | * @param string $key header's section name |
||
| 827 | * @param string $type type of the section (i.e. 'numeric', '/', '<<', etc.) |
||
| 828 | * @param string|array|null $default default value for header's section |
||
| 829 | * |
||
| 830 | * @return string|array|null value of obj header's section, or default value if none found, or its type doesn't match $type param |
||
| 831 | */ |
||
| 832 | private function getHeaderValue(?array $headerDic, string $key, string $type, $default = '') |
||
| 833 | { |
||
| 834 | if (false === \is_array($headerDic)) { |
||
| 835 | return $default; |
||
| 836 | } |
||
| 837 | |||
| 838 | /* |
||
| 839 | * It recieves dictionary of header fields, as it is returned by RawDataParser::getRawObject, |
||
| 840 | * iterates over it, searching for section of type '/' whith requested key. |
||
| 841 | * If such a section is found, it tries to receive it's value (next object in dictionary), |
||
| 842 | * returning it, if it matches requested type, or default value otherwise. |
||
| 843 | */ |
||
| 844 | foreach ($headerDic as $i => $val) { |
||
| 845 | $isSectionName = \is_array($val) && 3 == \count($val) && '/' == $val[0]; |
||
| 846 | if ( |
||
| 847 | $isSectionName |
||
| 848 | && $val[1] == $key |
||
| 849 | && isset($headerDic[$i + 1]) |
||
| 850 | ) { |
||
| 851 | $isSectionValue = \is_array($headerDic[$i + 1]) && 1 < \count($headerDic[$i + 1]); |
||
| 852 | |||
| 853 | return $isSectionValue && $type == $headerDic[$i + 1][0] |
||
| 854 | ? $headerDic[$i + 1][1] |
||
| 855 | : $default; |
||
| 856 | } |
||
| 857 | } |
||
| 858 | |||
| 859 | return $default; |
||
| 860 | } |
||
| 861 | |||
| 862 | /** |
||
| 863 | * Get Cross-Reference (xref) table and trailer data from PDF document data. |
||
| 864 | * |
||
| 865 | * @param int $offset xref offset (if known) |
||
| 866 | * @param array $xref previous xref array (if any) |
||
| 867 | * |
||
| 868 | * @return array containing xref and trailer data |
||
| 869 | * |
||
| 870 | * @throws \Exception if it was unable to find startxref |
||
| 871 | * @throws \Exception if it was unable to find xref |
||
| 872 | */ |
||
| 873 | protected function getXrefData(string $pdfData, int $offset = 0, array $xref = []): array |
||
| 934 | } |
||
| 935 | |||
| 936 | /** |
||
| 937 | * Parses PDF data and returns extracted data as array. |
||
| 938 | * |
||
| 939 | * @param string $data PDF data to parse |
||
| 940 | * |
||
| 941 | * @return array array of parsed PDF document objects |
||
| 942 | * |
||
| 943 | * @throws EmptyPdfException if empty PDF data given |
||
| 944 | * @throws MissingPdfHeaderException if PDF data missing `%PDF-` header |
||
| 945 | */ |
||
| 946 | public function parseData(string $data): array |
||
| 978 | } |
||
| 979 | } |
||
| 980 |
Loading history...
If the size of the collection does not change during the iteration, it is generally a good practice to compute it beforehand, and not on each iteration: