First external release

src/Spout/Writer/Helper/XLSX/SharedStringsHelper.php

@@ -0,0 +1,99 @@
+<?php
+
+namespace Box\Spout\Writer\Helper\XLSX;
+
+use Box\Spout\Common\Exception\IOException;
+
+/**
+ * Class SharedStringsHelper
+ * This class provides helper functions to write shared strings
+ *
+ * @package Box\Spout\Writer\Helper\XLSX
+ */
+class SharedStringsHelper
+{
+    const SHARED_STRINGS_FILE_NAME = 'sharedStrings.xml';
+
+    const SHARED_STRINGS_XML_FILE_FIRST_PART_HEADER = <<<EOD
+<?xml version="1.0" encoding="UTF-8" standalone="yes"?>
+<sst xmlns="http://schemas.openxmlformats.org/spreadsheetml/2006/main"
+EOD;
+
+    /**
+     * This number must be really big so that the no generated file will have more strings than that.
+     * If the strings number goes above, characters will be overwritten in an unwanted way and will corrupt the file.
+     */
+    const DEFAULT_STRINGS_COUNT_PART = 'count="9999999999999" uniqueCount="9999999999999"';
+
+    /** @var int Number of shared strings already written */
+    protected $numSharedStrings = 0;
+
+    /** @var \Box\Spout\Common\Escaper\XLSX Strings escaper */
+    protected $stringsEscaper;
+
+    /**
+     * @param string $xlFolder Path to the "xl" folder
+     */
+    public function __construct($xlFolder)
+    {
+        $sharedStringsFilePath = $xlFolder . DIRECTORY_SEPARATOR . self::SHARED_STRINGS_FILE_NAME;
+        $this->sharedStringsFilePointer = fopen($sharedStringsFilePath, 'w');
+
+        $this->throwIfSharedStringsFilePointerIsNotAvailable();
+
+        // the headers is split into different parts so that we can fseek and put in the correct count and uniqueCount later
+        $header = self::SHARED_STRINGS_XML_FILE_FIRST_PART_HEADER . ' ' . self::DEFAULT_STRINGS_COUNT_PART . '>' . PHP_EOL;
+        fwrite($this->sharedStringsFilePointer, $header);
+
+        $this->stringsEscaper = new \Box\Spout\Common\Escaper\XLSX();
+    }
+
+    /**
+     * Checks if the book has been created. Throws an exception if not created yet.
+     *
+     * @return void
+     * @throws \Box\Spout\Common\Exception\IOException If the sheet data file cannot be opened for writing
+     */
+    protected function throwIfSharedStringsFilePointerIsNotAvailable()
+    {
+        if (!$this->sharedStringsFilePointer) {
+            throw new IOException('Unable to open shared strings file for writing.');
+        }
+    }
+
+    /**
+     * Writes the given string into the sharedStrings.xml file.
+     * Starting and ending whitespaces are preserved.
+     *
+     * @param string $string
+     * @return int ID of the written shared string
+     */
+    public function writeString($string)
+    {
+        fwrite($this->sharedStringsFilePointer, '    <si><t xml:space="preserve">' . $this->stringsEscaper->escape($string) . '</t></si>' . PHP_EOL);
+        $this->numSharedStrings++;
+
+        // Shared string ID is zero-based
+        return ($this->numSharedStrings - 1);
+    }
+
+    /**
+     * Finishes writing the data in the sharedStrings.xml file and closes the file.
+     *
+     * @return void
+     */
+    public function close()
+    {
+        fwrite($this->sharedStringsFilePointer, '</sst>');
+
+        // Replace the default strings count with the actual number of shared strings in the file header
+        $firstPartHeaderLength = strlen(self::SHARED_STRINGS_XML_FILE_FIRST_PART_HEADER);
+        $defaultStringsCountPartLength = strlen(self::DEFAULT_STRINGS_COUNT_PART);
+
+        // Adding 1 to take into account the space between the last xml attribute and "count"
+        fseek($this->sharedStringsFilePointer, $firstPartHeaderLength + 1);
+        fwrite($this->sharedStringsFilePointer, sprintf("%-{$defaultStringsCountPartLength}s", 'count="' . $this->numSharedStrings . '" uniqueCount="' . $this->numSharedStrings . '"'));
+
+        fclose($this->sharedStringsFilePointer);
+    }
+}