Initial Commit

src/HeaderTagInterpreter.php

@@ -0,0 +1,32 @@
+<?php
+/**
+ * Created by PhpStorm.
+ * User: casey
+ * Date: 12/30/14
+ * Time: 12:32 PM
+ */
+
+namespace TOC;
+
+/**
+ * Interprets header tags
+ *
+ * @package TOC
+ */
+trait HeaderTagInterpreter
+{
+    /**
+     * Convert a topLevel and depth to H1..H6 tags array
+     *
+     * @param int $topLevel
+     * @param int $depth
+     * @return array  Array of header tags; ex: ['h1', 'h2', 'h3']
+     */
+    protected function determineHeaderTags($topLevel, $depth)
+    {
+        $desired = range((int) $topLevel, (int) $topLevel + ((int) $depth - 1));
+        $allowed = [1, 2, 3, 4, 5, 6];
+
+        return array_map(function($v) { return 'h'.$v; }, array_intersect($desired, $allowed));
+    }
+}

src/Sluggifier.php

@@ -0,0 +1,67 @@
+<?php
+/**
+ * Created by PhpStorm.
+ * User: casey
+ * Date: 12/30/14
+ * Time: 12:48 PM
+ */
+
+namespace TOC;
+
+use Cocur\Slugify\Slugify;
+
+/**
+ * Sluggifier creates slugs text without repeating the same string twice per instance
+ *
+ * @package TOC
+ */
+class Sluggifier
+{
+    /**
+     * @var \Cocur\Slugify\Slugify
+     */
+    private $slugify;
+
+    /**
+     * @var array
+     */
+    private $used;
+
+    // ---------------------------------------------------------------
+
+    /**
+     * Constructor
+     *
+     * @param \Cocur\Slugify\Slugify $slugify
+     */
+    public function __construct(Slugify $slugify = null)
+    {
+        $this->used = array();
+        $this->slugify = $slugify ?: new Slugify();
+    }
+
+    // ---------------------------------------------------------------
+
+    /**
+     * Slugify
+     *
+     * @param string $text
+     * @return string
+     */
+    public function slugify($text)
+    {
+        $slugged = $this->slugify->slugify($text);
+
+        $ct = 1;
+        $orig = $slugged;
+        while (in_array($slugged, $this->used)) {
+            $slugged = $orig . '-' . $ct;
+            $ct++;
+        }
+
+        $this->used[] = $slugged;
+        return $slugged;
+    }
+}
+
+/* EOF: Sluggifier.php */

src/TocGenerator.php

@@ -0,0 +1,107 @@
+<?php
+
+// Header here
+// ---------------------------------------------------------------
+
+namespace TOC;
+
+use Sunra\PhpSimple\HtmlDomParser;
+use RuntimeException;
+
+/**
+ * Class TocGenerator
+ *
+ * @author Casey McLaughlin <caseyamcl@gmail.com>
+ */
+class TocGenerator
+{
+    use HeaderTagInterpreter;
+
+    // ---------------------------------------------------------------
+
+    /**
+     * @var \Sunra\PhpSimple\HtmlDomParser
+     */
+    private $domParser;
+
+    // ---------------------------------------------------------------
+
+    /**
+     * Constructor
+     *
+     * @param \Sunra\PhpSimple\HtmlDomParser $domParser
+     */
+    public function __construct(HtmlDomParser $domParser = null)
+    {
+        $this->domParser = $domParser ?: new HtmlDomParser();
+    }
+
+    // ---------------------------------------------------------------
+
+    /**
+     * Get Link Items
+     *
+     * @param string  $markup    Content to get items from
+     * @param int     $topLevel  Top Header (1 through 6)
+     * @param int     $depth     Depth (1 through 6)
+     * @return array  Array of items  ['anchor' => 'display text', ...]
+     */
+    public function getItems($markup, $topLevel = 1, $depth = 2)
+    {
+        // Empty?  Do nothing.
+        if (trim($markup) == '') {
+            return [];
+        }
+
+        // Parse HTML
+        $items  = [];
+        $tags   = $this->determineHeaderTags($topLevel, $depth);
+        $parsed = $this->domParser->str_get_html($markup);
+
+        // Runtime exception for bad code
+        if ( ! $parsed) {
+            throw new RuntimeException("Could not parse HTML");
+        }
+
+        // Extract items
+        foreach ($parsed->find(implode(', ', $tags)) as $tag) {
+
+            if ( ! $tag->id) {
+                continue;
+            }
+
+            $dispText = $tag->title ?: $tag->plaintext;
+            $items[$tag->id] = $dispText;
+        }
+
+        return $items;
+    }
+
+    // ---------------------------------------------------------------
+
+    /**
+     * Get HTML Links in list form
+     *
+     * @param string   $markup    Content to get items from
+     * @param int      $topLevel  Top Header (1 through 6)
+     * @param int      $depth     Depth (1 through 6)
+     * @return string  HTML <LI> items
+     */
+    public function getHtmlItems($markup, $topLevel = 1, $depth = 2, $titleTemplate = 'Go to %s')
+    {
+        $arr = [];
+
+        foreach ($this->getItems($markup, $topLevel, $depth) as $anchor => $displayText) {
+            $arr[] = sprintf(
+                "<li><a title='%s' href='#%s'>%s</a></li>",
+                sprintf($titleTemplate, $displayText),
+                $anchor,
+                $displayText
+            );
+        }
+
+        return implode('', $arr);
+    }
+}
+
+/* EOF: TocGenerator.php */

src/TocMarkupFixer.php

@@ -0,0 +1,81 @@
+<?php
+/**
+ * Created by PhpStorm.
+ * User: casey
+ * Date: 12/30/14
+ * Time: 12:20 PM
+ */
+
+namespace TOC;
+
+use RuntimeException;
+use Sunra\PhpSimple\HtmlDomParser;
+
+/**
+ * TOC Markup Fixer adds `id` attributes to all H1...H6 tags where they do not
+ * already exist
+ *
+ * @author Casey McLaughlin <caseyamcl@gmail.com>
+ */
+class TocMarkupFixer
+{
+    use HeaderTagInterpreter;
+
+    // ---------------------------------------------------------------
+
+    /**
+     * @var HtmlDomParser
+     */
+    private $domParser;
+
+    // ---------------------------------------------------------------
+
+    /**
+     * Constructor
+     *
+     * @param HtmlDomParser $domParser
+     */
+    public function __construct(HtmlDomParser $domParser = null)
+    {
+        $this->domParser = $domParser ?: new HtmlDomParser();
+    }
+
+    // ---------------------------------------------------------------
+
+    /**
+     * Fix markup
+     *
+     * @param string $markup
+     * @param int    $topLevel
+     * @param int    $depth
+     * @return string Markup with added IDs
+     * @throws RuntimeException
+     */
+    public function fix($markup, $topLevel = 1, $depth = 2)
+    {
+        $sluggifier = new Sluggifier();
+
+        $tags   = $this->determineHeaderTags($topLevel, $depth);
+        $parsed = $this->domParser->str_get_html($markup);
+
+        // Runtime exception for bad code
+        if ( ! $parsed) {
+            throw new RuntimeException("Could not parse HTML");
+        }
+
+        // Extract items
+        foreach ($parsed->find(implode(', ', $tags)) as $tag) {
+
+            // Ignore tags that already have IDs
+            if ($tag->id) {
+                continue;
+            }
+
+            $tag->id = $sluggifier->slugify($tag->title ?: $tag->plaintext);
+        }
+
+        return (string) $parsed;
+    }
+}
+
+/* EOF: TocMarkupFixer.php */

src/TocTwigExtension.php

@@ -0,0 +1,85 @@
+<?php
+
+namespace TOC;
+
+use Twig_Extension;
+
+/**
+ * Class TocTwigExtension
+ *
+ * @author Casey McLaughlin <caseyamcl@gmail.com>
+ */
+class TocTwigExtension extends Twig_Extension
+{
+    /**
+     * @var \TOC\TocGenerator
+     */
+    private $generator;
+
+    /**
+     * @var \TOC\TocMarkupFixer
+     */
+    private $fixer;
+
+    // ---------------------------------------------------------------
+
+    /**
+     * Constructor
+     *
+     * @param \TOC\TocGenerator   $generator
+     * @param \TOC\TocMarkupFixer $fixer
+     */
+    public function __construct(TocGenerator $generator = null, TocMarkupFixer $fixer = null)
+    {
+        $this->generator = $generator ?: new TocGenerator();
+        $this->fixer     = $fixer     ?: new TocMarkupFixer();
+    }
+
+    // ---------------------------------------------------------------
+
+    public function getFilters()
+    {
+        $filters = parent::getFilters();
+
+        $filters[] = new \Twig_SimpleFilter('add_anchors', function($str, $top = 1, $depth = 2) {
+            return $this->fixer->fix($str, $top, $depth);
+        });
+
+        return $filters;
+    }
+
+    // ---------------------------------------------------------------
+
+    public function getFunctions()
+    {
+        $functions = parent::getFunctions();
+
+        // ~~~
+
+        $functions[] = new \Twig_SimpleFunction('toc', function($markup, $top = 1, $depth = 2, $titleTemplate = null) {
+            return ($titleTemplate)
+                ? $this->generator->getHtmlItems($markup, $top, $depth, $titleTemplate)
+                : $this->generator->getHtmlItems($markup, $top, $depth);
+        });
+
+        // ~~~
+
+        $functions[] = new \Twig_SimpleFunction('toc_items', function($markup, $top = 1, $depth = 2) {
+            return $this->generator->getItems($markup, $top, $depth);
+        });
+
+        return $functions;
+    }
+
+    // ---------------------------------------------------------------
+
+    /**
+     * Returns the name of the extension.
+     *
+     * @return string The extension name
+     */
+    public function getName()
+    {
+        return 'toc';
+    }
+}