[WIP] Initial work

bootstrap.php

@@ -2,6 +2,10 @@
 
 namespace Drupal\Composer\ClassLoader;
 
+// Register the class loader.
+$bootstrap = new AutoloaderBootstrap();
+$bootstrap->register();
+
 /**
  * Class AutoloaderBootstrap
  *
@@ -22,6 +26,9 @@ public function register() {
         return;
       }
     }
+    // TODO: Load the *correct* composer.json in a decent OO way.
+    // Parse the composer.json.
+    Loader::setClassMap(json_decode(file_get_contents('composer.json')));
     $this::load();
   }
 
@@ -47,7 +54,3 @@ protected static function unload() {
   }
 
 }
-
-// Register the class loader.
-$bootstrap = new AutoloaderBootstrap();
-$bootstrap->register();

src/ClassLoaderException.php

@@ -0,0 +1,10 @@
+<?php
+
+/**
+ * @file
+ * Contains Drupal\Composer\ClassLoader\ClassLoaderException.
+ */
+
+namespace Drupal\Composer\ClassLoader;
+
+class ClassLoaderException extends \Exception {}

src/Discovery/PathFinderBase.php

@@ -10,4 +10,21 @@
 
 class PathFinderBase implements PathFinderInterface {
 
+  /**
+   * The relative path.
+   *
+   * @var string
+   */
+  protected $path;
+
+  /**
+   * Constructs a PathFinderBase object.
+   *
+   * @param string $path
+   *   The relative path to find.
+   */
+  public function __construct($path) {
+    $this->path = $path;
+  }
+
 }

src/Discovery/PathFinderContrib.php

@@ -8,6 +8,6 @@
 namespace Drupal\Composer\ClassLoader\Discovery;
 
 
-class PathFinderContrib implements PathFinderInterface {
+class PathFinderContrib extends PathFinderBase implements PathFinderInterface {
 
 }

src/Discovery/PathFinderCore.php

@@ -8,6 +8,6 @@
 namespace Drupal\Composer\ClassLoader\Discovery;
 
 
-class PathFinderCore implements PathFinderInterface {
+class PathFinderCore extends PathFinderBase implements PathFinderInterface {
 
 }

src/Discovery/PathFinderNull.php

@@ -0,0 +1,20 @@
+<?php
+/**
+ * @file
+ * Contains Drupal\Composer\ClassLoader\Discovery\PathFinderNull.
+ */
+
+namespace Drupal\Composer\ClassLoader\Discovery;
+
+
+class PathFinderNull extends PathFinderBase implements PathFinderInterface {
+
+  /**
+   * {@inheritdoc}
+   */
+  public function requireFile() {
+    require_once $this->path;
+    return TRUE;
+  }
+
+}

src/Loader.php

@@ -10,4 +10,35 @@
 
 class Loader implements LoaderInterface {
 
+  /**
+   * Class maps.
+   *
+   * Contains the name of the class, including the namespace, as the key. The
+   * value is the file name with path tokens.
+   *
+   * @var
+   */
+  protected static $classMap;
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function autoload($class) {
+    if (!in_array($class, static::$classMap)) {
+      return FALSE;
+    }
+    $resolver = new TokenResolver(static::$classMap[$class]);
+    $finder = $resolver->resolve();
+    // Have the path finder require the file and return TRUE or FALSE if it
+    // found the file or not.
+    return $finder->require();
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public static function setClassMap(array $class_map) {
+    static::$classMap = $class_map;
+  }
+
 }

src/LoaderInterface.php

@@ -10,4 +10,22 @@
 
 interface LoaderInterface {
 
+  /**
+   * Autoload static method.
+   *
+   * @param string $class
+   *   The name of the class to check or load.
+   *
+   * @return bool
+   *   TRUE if the class is currently available, FALSE otherwise.
+   */
+  public static function autoload($class);
+
+  /**
+   * Sets the class map.
+   *
+   * @param array $class_map
+   */
+  public static function setClassMap(array $class_map);
+
 }

src/TokenResolver.php

@@ -0,0 +1,126 @@
+<?php
+
+/**
+ * @file
+ * Contains Drupal\Composer\ClassLoader\TokenResolver.
+ */
+
+namespace Drupal\Composer\ClassLoader;
+
+
+class TokenResolver implements TokenResolverInterface {
+
+  /**
+   * Path.
+   *
+   * @var string
+   */
+  protected $path;
+
+  /**
+   * Supported tokens.
+   *
+   * The key is the name of the token, the value is the class that instantiates.
+   *
+   * @var array
+   */
+  private $supportedTokens = array(
+    'DRUPAL_ROOT' => 'Discovery/PathFinderCore',
+    'DRUPAL_CONTRIB' => 'Discovery/PathFinderContrib',
+  );
+
+  /**
+   * Constructs a TokenResolver object.
+   *
+   * @param string $tokenized_path
+   *   The path containing a potential token.
+   */
+  public function __construct($tokenized_path = '') {
+    $this->path = $tokenized_path;
+  }
+
+  /**
+   * {@inheritdoc}
+   */
+  public function resolve() {
+    // If the path is not tokenized, then return the NULL discovery object.
+    if (file_exists($this->path)) {
+      return new Discovery\PathFinderNull($this->path);
+    }
+    if (!$this->getToken()) {
+      return NULL;
+    }
+    $class_name = $this->getClassName();
+    $arguments[] = $this->cleanToken();
+    // Add more arguments to the constructor, like the module name.
+    $arguments += $this->parseArguments();
+    return new $class_name($arguments);
+  }
+
+  /**
+   * Removes the token from the tokenized path.
+   *
+   * @throws ClassLoaderException
+   *   If no token can be found.
+   *
+   * @return string
+   *   The cleaned path.
+   */
+  protected function cleanToken() {
+    if ($token_name = $this->getToken()) {
+      // Remove the token and arguments and return the path.
+      $path = substr($this->path, strlen($token_name));
+      return preg_replace('/<.*>/', '', $path);
+    }
+    $message = sprintf('No token could be found in "%s". Available tokens are: %s.', $this->path, implode(', ', array_keys($this->supportedTokens)));
+    throw new ClassLoaderException($message);
+  }
+
+  /**
+   * Checks if the current tokenized path contains a known token.
+   *
+   * @return string
+   *   The token found. NULL otherwise.
+   */
+  protected function getToken() {
+    static $token_name;
+    if (isset($token_name)) {
+      return $token_name;
+    }
+    foreach (array_keys($this->supportedTokens) as $token_name) {
+      if (strpos($this->path, $token_name) === 0) {
+        return $token_name;
+      }
+    }
+    return NULL;
+  }
+
+  /**
+   * Gets the class name corresponding to the token.
+   *
+   * @return string
+   *   The class name.
+   */
+  protected function getClassName() {
+    $token_name = $this->getToken();
+    return $token_name ? $this->supportedTokens[$token_name] : NULL;
+  }
+
+  /**
+   * Gets the arguments in the token.
+   *
+   * @return string[]
+   *   A numeric array containing the token arguments.
+   */
+  protected function parseArguments() {
+    $token_name = $this->getToken();
+    $delimiter = '/';
+    $matches = array();
+    if (preg_match($delimiter . preg_quote($token_name) . '<(.+)>.*' . $delimiter, $this->path, $matches)) {
+      // Some arguments were found.
+      return explode(',', $matches[2]);
+    }
+    return array();
+  }
+
+}

src/TokenResolverInterface.php

@@ -0,0 +1,20 @@
+<?php
+
+/**
+ * @file
+ * Contains Drupal\Composer\ClassLoader\TokenResolverInterface.
+ */
+
+namespace Drupal\Composer\ClassLoader;
+
+
+interface TokenResolverInterface {
+
+  /**
+   * Finds the token in the give path and returns the discovery object.
+   *
+   * @return Discovery\PathFinderInterface
+   *   The path finder class or NULL.
+   */
+  public function resolve();
+}