recursive resolver with directives

components/ILIAS/Component/src/Dependencies/In.php

@@ -75,4 +75,9 @@ public function getResolvedBy(): array
     {
         return $this->resolved_by;
     }
+
+    public function isResolved(): bool
+    {
+        return count($this->resolved_by) > 0;
+    }
 }

components/ILIAS/Component/src/Dependencies/ResolutionDirective.php

@@ -0,0 +1,33 @@
+<?php
+
+/**
+ * This file is part of ILIAS, a powerful learning management system
+ * published by ILIAS open source e-Learning e.V.
+ *
+ * ILIAS is licensed with the GPL-3.0,
+ * see https://www.gnu.org/licenses/gpl-3.0.en.html
+ * You should have received a copy of said license along with the
+ * source code, too.
+ *
+ * If this is not the case or you just want to try ILIAS, you'll find
+ * us at:
+ * https://www.ilias.de
+ * https://github.com/ILIAS-eLearning
+ *
+ *********************************************************************/
+
+declare(strict_types=1);
+
+namespace ILIAS\Component\Dependencies;
+
+/**
+ * Specifies a certain way to disambiguate or resolve some dependency. Do not
+ * extend, won't work!
+ *
+ * "specificity" is meant to order directives, more specific directives come
+ * first.
+ */
+interface ResolutionDirective
+{
+    public function getSpecificity(): int;
+}

components/ILIAS/Component/src/Dependencies/ResolutionDirective/ForXUseY.php

@@ -0,0 +1,53 @@
+<?php
+
+/**
+ * This file is part of ILIAS, a powerful learning management system
+ * published by ILIAS open source e-Learning e.V.
+ *
+ * ILIAS is licensed with the GPL-3.0,
+ * see https://www.gnu.org/licenses/gpl-3.0.en.html
+ * You should have received a copy of said license along with the
+ * source code, too.
+ *
+ * If this is not the case or you just want to try ILIAS, you'll find
+ * us at:
+ * https://www.ilias.de
+ * https://github.com/ILIAS-eLearning
+ *
+ *********************************************************************/
+
+declare(strict_types=1);
+
+namespace ILIAS\Component\Dependencies\ResolutionDirective;
+
+use ILIAS\Component\Dependencies\ResolutionDirective;
+
+/**
+ * Tells the Resolver to use an implementation with a certain class name to
+ * resolve a certain dependency.
+ *
+ * Specifity is 1.
+ */
+class ForXUseY implements ResolutionDirective
+{
+    public function __construct(
+        protected string $x,
+        protected string $y,
+    ) {
+    }
+
+    public function getX(): string
+    {
+        return $this->x;
+    }
+
+    public function getY(): string
+    {
+        return $this->y;
+    }
+
+    public function getSpecificity(): int
+    {
+        return 1;
+    }
+}

components/ILIAS/Component/src/Dependencies/ResolutionDirective/InComponent.php

@@ -0,0 +1,58 @@
+<?php
+
+/**
+ * This file is part of ILIAS, a powerful learning management system
+ * published by ILIAS open source e-Learning e.V.
+ *
+ * ILIAS is licensed with the GPL-3.0,
+ * see https://www.gnu.org/licenses/gpl-3.0.en.html
+ * You should have received a copy of said license along with the
+ * source code, too.
+ *
+ * If this is not the case or you just want to try ILIAS, you'll find
+ * us at:
+ * https://www.ilias.de
+ * https://github.com/ILIAS-eLearning
+ *
+ *********************************************************************/
+
+declare(strict_types=1);
+
+namespace ILIAS\Component\Dependencies\ResolutionDirective;
+
+use ILIAS\Component\Dependencies\ResolutionDirective;
+
+/**
+ * Tells the Resolver to apply that directives only in the given component.
+ *
+ * Specifity is one more than the maximum specifity of the included directives.
+ */
+class InComponent implements ResolutionDirective
+{
+    protected int $specificity;
+    protected array $directives;
+
+    public function __construct(
+        protected string $component_name,
+        ResolutionDirective ...$directives
+    ) {
+        usort($directives, fn($l, $r) => $l->getSpecificity() <=> $r->getSpecificity());
+        $this->directives = $directives;
+        $this->specificity = max(array_map(fn($d) => $d->getSpecificity(), $directives)) + 1;
+    }
+
+    public function getComponentName(): string
+    {
+        return $this->component_name;
+    }
+
+    public function getDirectives(): array
+    {
+        return $this->directives;
+    }
+
+    public function getSpecificity(): int
+    {
+        return $this->specificity;
+    }
+}

components/ILIAS/Component/src/Dependencies/ResolutionDirective/WhenPulling.php

@@ -0,0 +1,47 @@
+<?php
+
+/**
+ * This file is part of ILIAS, a powerful learning management system
+ * published by ILIAS open source e-Learning e.V.
+ *
+ * ILIAS is licensed with the GPL-3.0,
+ * see https://www.gnu.org/licenses/gpl-3.0.en.html
+ * You should have received a copy of said license along with the
+ * source code, too.
+ *
+ * If this is not the case or you just want to try ILIAS, you'll find
+ * us at:
+ * https://www.ilias.de
+ * https://github.com/ILIAS-eLearning
+ *
+ *********************************************************************/
+
+declare(strict_types=1);
+
+namespace ILIAS\Component\Dependencies\ResolutionDirective;
+
+use ILIAS\Component\Dependencies\ResolutionDirective;
+
+/**
+ * Tells the Resolver to apply certain directives when some specifc thing is pulled.
+ *
+ * Specifity is one more than the maximum specifity of the included directives.
+ */
+class WhenPulling implements ResolutionDirective
+{
+    protected int $specificity;
+    protected array $directives;
+
+    public function __construct(
+        protected string $provision,
+        ResolutionDirective ...$directives
+    ) {
+        $this->directives = $directives;
+        $this->specificity = max(array_map(fn($d) => $d->getSpecificity(), $directives)) + 1;
+    }
+
+    public function getSpecificity(): int
+    {
+        return $this->specificity;
+    }
+}