Move text extraction code out of document parsing namespaces

src/Document/ContentStream/ContentStream.php

@@ -5,18 +5,14 @@
 
 use PrinsFrank\PdfParser\Document\ContentStream\Command\ContentStreamCommand;
 use PrinsFrank\PdfParser\Document\ContentStream\Command\Operator\State\GraphicsStateOperator;
-use PrinsFrank\PdfParser\Document\ContentStream\Command\Operator\State\Interaction\InteractsWithTransformationMatrix;
 use PrinsFrank\PdfParser\Document\ContentStream\Command\Operator\State\Interaction\InteractsWithTextState;
+use PrinsFrank\PdfParser\Document\ContentStream\Command\Operator\State\Interaction\InteractsWithTransformationMatrix;
 use PrinsFrank\PdfParser\Document\ContentStream\Command\Operator\State\Interaction\ProducesPositionedTextElements;
 use PrinsFrank\PdfParser\Document\ContentStream\Object\TextObject;
-use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\LineGroupingStrategy\LineGroupingStrategy;
 use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\PositionedTextElement;
 use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\TextState;
 use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\TransformationMatrix;
-use PrinsFrank\PdfParser\Document\Document;
-use PrinsFrank\PdfParser\Document\Object\Decorator\Page;
 use PrinsFrank\PdfParser\Exception\ParseFailureException;
-use PrinsFrank\PdfParser\Exception\PdfParserException;
 
 /** @api */
 readonly class ContentStream {
@@ -76,51 +72,4 @@ public function getPositionedTextElements(): array {
 
         return $positionedTextElements;
     }
-
-    /** @throws PdfParserException */
-    public function getText(Document $document, Page $page, LineGroupingStrategy $lineGroupingStrategy): string {
-        $text = '';
-        foreach ($lineGroupingStrategy->group($this->getPositionedTextElements()) as $i => $positionedTextElementsForLine) {
-            if ($i !== 0) {
-                $text .= "\n";
-            }
-
-            $previousTextElementOnLine = null;
-            foreach ($positionedTextElementsForLine as $positionedTextElement) {
-                $elementText = $positionedTextElement->getText($document, $page);
-                if ($elementText === '') {
-                    $previousTextElementOnLine = $positionedTextElement;
-                    continue;
-                }
-
-                if ($previousTextElementOnLine !== null) {
-                    // The gap between two elements is what remains of the horizontal distance once the previous
-                    // element's own advance is subtracted. That advance is reconstructed by getAdvanceWidth() because
-                    // Tj/TJ do not move the text matrix here; ignoring it (as the old next-element-font width did) left
-                    // the TJ kerning term in the gap and forced a slack threshold.
-                    $gap = $positionedTextElement->absoluteMatrix->offsetX
-                        - $previousTextElementOnLine->absoluteMatrix->offsetX
-                        - $previousTextElementOnLine->getAdvanceWidth($document, $page);
-
-                    $wordBreakThreshold = $previousTextElementOnLine->textState->getFontSize()
-                        * $previousTextElementOnLine->absoluteMatrix->scaleX
-                        * ($previousTextElementOnLine->textState->scale / 100)
-                        * PositionedTextElement::WORD_BREAK_THRESHOLD_EM;
-
-                    if (
-                        $gap >= $wordBreakThreshold
-                        && str_ends_with($text, ' ') === false
-                        && str_starts_with($elementText, ' ') === false
-                    ) {
-                        $text .= ' ';
-                    }
-                }
-
-                $text .= $elementText;
-                $previousTextElementOnLine = $positionedTextElement;
-            }
-        }
-
-        return $text;
-    }
 }

src/Document/Object/Decorator/Page.php

@@ -2,17 +2,18 @@
 
 namespace PrinsFrank\PdfParser\Document\Object\Decorator;
 
-use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\LineGroupingStrategy\TextOverlapStrategy;
+use PrinsFrank\PdfParser\Document\ContentStream\ContentStream;
+use PrinsFrank\PdfParser\Document\ContentStream\ContentStreamParser;
 use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\PositionedTextElement;
 use PrinsFrank\PdfParser\Document\Dictionary\Dictionary;
 use PrinsFrank\PdfParser\Document\Dictionary\DictionaryKey\DictionaryKey;
-use PrinsFrank\PdfParser\Document\ContentStream\ContentStream;
-use PrinsFrank\PdfParser\Document\ContentStream\ContentStreamParser;
 use PrinsFrank\PdfParser\Document\Dictionary\DictionaryValue\Rectangle\Rectangle;
 use PrinsFrank\PdfParser\Document\Dictionary\DictionaryValue\Reference\ReferenceValue;
 use PrinsFrank\PdfParser\Exception\InvalidArgumentException;
 use PrinsFrank\PdfParser\Exception\ParseFailureException;
 use PrinsFrank\PdfParser\Exception\PdfParserException;
+use PrinsFrank\PdfParser\Extraction\Text\TextExtractor;
+use PrinsFrank\PdfParser\Extraction\Text\TextGrouping\LineGrouping\TextOverlapStrategy;
 
 class Page extends DecoratedObject {
     /**
@@ -26,8 +27,7 @@ public function getPositionedTextElements(): array {
 
     /** @throws PdfParserException */
     public function getText(): string {
-        return $this->getContentStream()
-            ?->getText($this->document, $this, new TextOverlapStrategy()) ?? '';
+        return TextExtractor::extractText($this->getPositionedTextElements(), $this->document, $this, new TextOverlapStrategy());
     }
 
     /** @throws PdfParserException */

src/Extraction/Text/TextExtractor.php

@@ -0,0 +1,57 @@
+<?php declare(strict_types=1);
+
+namespace PrinsFrank\PdfParser\Extraction\Text;
+
+use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\PositionedTextElement;
+use PrinsFrank\PdfParser\Document\Document;
+use PrinsFrank\PdfParser\Document\Object\Decorator\Page;
+use PrinsFrank\PdfParser\Exception\PdfParserException;
+use PrinsFrank\PdfParser\Extraction\Text\TextGrouping\LineGrouping\LineGroupingStrategy;
+
+class TextExtractor {
+    /**
+     * @param list<PositionedTextElement> $positionedTextElements
+     * @throws PdfParserException
+     */
+    public static function extractText(array $positionedTextElements, Document $document, Page $page, LineGroupingStrategy $lineGroupingStrategy): string {
+        $text = '';
+        foreach ($lineGroupingStrategy->group($positionedTextElements) as $i => $positionedTextElementsForLine) {
+            if ($i !== 0) {
+                $text .= "\n";
+            }
+
+            $previousTextElementOnLine = null;
+            foreach ($positionedTextElementsForLine as $positionedTextElement) {
+                $elementText = $positionedTextElement->getText($document, $page);
+                if ($elementText === '') {
+                    $previousTextElementOnLine = $positionedTextElement;
+                    continue;
+                }
+
+                if ($previousTextElementOnLine !== null) {
+                    $gap = $positionedTextElement->absoluteMatrix->offsetX
+                        - $previousTextElementOnLine->absoluteMatrix->offsetX
+                        - $previousTextElementOnLine->getAdvanceWidth($document, $page);
+
+                    $wordBreakThreshold = $previousTextElementOnLine->textState->getFontSize()
+                        * $previousTextElementOnLine->absoluteMatrix->scaleX
+                        * ($previousTextElementOnLine->textState->scale / 100)
+                        * PositionedTextElement::WORD_BREAK_THRESHOLD_EM;
+
+                    if (
+                        $gap >= $wordBreakThreshold
+                        && str_ends_with($text, ' ') === false
+                        && str_starts_with($elementText, ' ') === false
+                    ) {
+                        $text .= ' ';
+                    }
+                }
+
+                $text .= $elementText;
+                $previousTextElementOnLine = $positionedTextElement;
+            }
+        }
+
+        return $text;
+    }
+}

src/Document/ContentStream/PositionedText/LineGroupingStrategy/LineGroupingStrategy.php → src/Extraction/Text/TextGrouping/LineGrouping/LineGroupingStrategy.php

@@ -1,6 +1,6 @@
 <?php declare(strict_types=1);
 
-namespace PrinsFrank\PdfParser\Document\ContentStream\PositionedText\LineGroupingStrategy;
+namespace PrinsFrank\PdfParser\Extraction\Text\TextGrouping\LineGrouping;
 
 use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\PositionedTextElement;
 

src/Document/ContentStream/PositionedText/LineGroupingStrategy/StrictLineGrouping.php → src/Extraction/Text/TextGrouping/LineGrouping/StrictLineGrouping.php

@@ -1,6 +1,6 @@
 <?php declare(strict_types=1);
 
-namespace PrinsFrank\PdfParser\Document\ContentStream\PositionedText\LineGroupingStrategy;
+namespace PrinsFrank\PdfParser\Extraction\Text\TextGrouping\LineGrouping;
 
 use Override;
 use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\PositionedTextElement;

src/Document/ContentStream/PositionedText/LineGroupingStrategy/TextOverlapStrategy.php → src/Extraction/Text/TextGrouping/LineGrouping/TextOverlapStrategy.php

@@ -1,6 +1,6 @@
 <?php declare(strict_types=1);
 
-namespace PrinsFrank\PdfParser\Document\ContentStream\PositionedText\LineGroupingStrategy;
+namespace PrinsFrank\PdfParser\Extraction\Text\TextGrouping\LineGrouping;
 
 use Override;
 use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\PositionedTextElement;
@@ -25,9 +25,6 @@ public function __construct(
 
     #[Override]
     public function group(array $positionedTextElements): iterable {
-        // Order lines top to bottom by descending offsetY. Not abs(offsetY): a page whose MediaBox origin sits
-        // above its content (negative lower-left, e.g. [0 -792 612 0]) has all-negative offsetY with the topmost
-        // line the least negative, which abs() would reverse.
         usort(
             $positionedTextElements,
             fn(PositionedTextElement $a, PositionedTextElement $b): int => $b->absoluteMatrix->offsetY <=> $a->absoluteMatrix->offsetY,

tests/Unit/Document/ContentStream/PositionedText/LineGroupingStrategy/TextOverlapStrategyTest.php

@@ -4,12 +4,12 @@
 
 use PHPUnit\Framework\Attributes\CoversClass;
 use PHPUnit\Framework\TestCase;
-use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\LineGroupingStrategy\TextOverlapStrategy;
 use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\PositionedTextElement;
 use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\TextSegment\TextSegment;
 use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\TextState;
 use PrinsFrank\PdfParser\Document\ContentStream\PositionedText\TransformationMatrix;
 use PrinsFrank\PdfParser\Document\Dictionary\DictionaryValue\TextString\TextStringValue;
+use PrinsFrank\PdfParser\Extraction\Text\TextGrouping\LineGrouping\TextOverlapStrategy;
 
 #[CoversClass(TextOverlapStrategy::class)]
 class TextOverlapStrategyTest extends TestCase {