From eb3a7add858c4531244ab27004fc15c91cb2b98e Mon Sep 17 00:00:00 2001
From: QWp6t <hi@qwp6t.me>
Date: Fri, 15 Jul 2016 05:31:02 -0700
Subject: [PATCH] Rework template wrapper, bring back template_part()

---
 src/filters.php                             |  2 +-
 src/helpers.php                             | 24 ++----
 src/lib/Sage/Template.php                   | 44 +++++++++++
 src/lib/Sage/Template/Partial.php           | 70 ++++++++++++++++++
 src/lib/Sage/Template/Wrapper.php           |  8 +-
 src/lib/Sage/Template/WrapperCollection.php | 81 ---------------------
 src/lib/Sage/Template/WrapperInterface.php  |  6 +-
 templates/layouts/base.php                  |  4 +-
 8 files changed, 130 insertions(+), 109 deletions(-)
 create mode 100644 src/lib/Sage/Template.php
 create mode 100644 src/lib/Sage/Template/Partial.php
 delete mode 100644 src/lib/Sage/Template/WrapperCollection.php

diff --git a/src/filters.php b/src/filters.php
index 9ca13b6..b5f1bf5 100644
--- a/src/filters.php
+++ b/src/filters.php
@@ -49,5 +49,5 @@ add_filter('template_include', function ($main) {
     if (!is_string($main) && !(is_object($main) && method_exists($main, '__toString'))) {
         return $main;
     }
-    return template_wrap(new Wrapper($main));
+    return ((new Template(new Wrapper($main)))->layout());
 }, 109);
diff --git a/src/helpers.php b/src/helpers.php
index d4dd53f..27461b8 100644
--- a/src/helpers.php
+++ b/src/helpers.php
@@ -2,29 +2,17 @@
 
 use Roots\Sage\Asset;
 use Roots\Sage\Assets\JsonManifest;
-use Roots\Sage\Template\WrapperCollection;
-use Roots\Sage\Template\WrapperInterface;
+use Roots\Sage\Template;
 
-/**
- * @param WrapperInterface $wrapper
- * @param string $slug
- * @return string
- * @throws \Exception
- * @SuppressWarnings(PHPMD.StaticAccess) This is a helper function, so we can suppress this warning
- */
-function template_wrap(WrapperInterface $wrapper, $slug = 'base')
+function template($layout = 'base')
 {
-    WrapperCollection::add($wrapper, $slug);
-    return $wrapper->getWrapper();
+    return Template::$instances[$layout];
 }
 
-/**
- * @param string $slug
- * @return string
- */
-function template_unwrap($slug = 'base')
+function template_part($template, array $context = [], $layout = 'base')
 {
-    return WrapperCollection::get($slug)->getTemplate();
+    extract($context);
+    include template($layout)->partial($template);
 }
 
 /**
diff --git a/src/lib/Sage/Template.php b/src/lib/Sage/Template.php
new file mode 100644
index 0000000..4dbf1cd
--- /dev/null
+++ b/src/lib/Sage/Template.php
@@ -0,0 +1,44 @@
+<?php namespace Roots\Sage;
+
+use Roots\Sage\Template\Partial;
+use Roots\Sage\Template\WrapperInterface;
+
+class Template
+{
+    /** @var Template[] */
+    public static $instances = [];
+
+    /** @var WrapperInterface */
+    protected $wrapper;
+
+    public function __construct(WrapperInterface $wrapper)
+    {
+        $this->wrapper = $wrapper;
+        self::$instances[$wrapper->slug()] = $this;
+    }
+
+    /**
+     * @return string Layout (FQPN of, e.g., `base-page.php`, `base.php`)
+     */
+    public function layout()
+    {
+        return $this->wrapper->wrap();
+    }
+
+    /**
+     * @return string Main template (FQPN of, e.g., `page.php`, `single.php`, `singular.php`)
+     */
+    public function main()
+    {
+        return $this->wrapper->unwrap();
+    }
+
+    /**
+     * @param string $template Delimited template path
+     * @return string Partial template (FQPN of, e.g., `content.php`, `page-header.php`
+     */
+    public function partial($template)
+    {
+        return (new Partial($template, $this->main()))->path();
+    }
+}
diff --git a/src/lib/Sage/Template/Partial.php b/src/lib/Sage/Template/Partial.php
new file mode 100644
index 0000000..97b8646
--- /dev/null
+++ b/src/lib/Sage/Template/Partial.php
@@ -0,0 +1,70 @@
+<?php namespace Roots\Sage\Template;
+
+class Partial
+{
+    protected static $cache = [];
+
+    public $main;
+    public $template;
+    public $delimiter = '-';
+
+    public function __construct($template, $main = '')
+    {
+        $this->template = $template;
+        $this->main = $main;
+    }
+
+    public function __toString()
+    {
+        return (string) $this->path();
+    }
+
+    /**
+     * Converts template into array of parts to be passed to locate_template()
+     *
+     * Here's an example of what happens:
+     *   (new Template('partials/content-single-audio'))->parts();
+     *   // => ['partials/content-single-audio.php', 'partials/content-single.php', 'partials/content.php']
+     * @return array Array of parts to pass to locate_template()
+     */
+    public function parts()
+    {
+        if ($parts = $this->cache('parts')) {
+            return $parts;
+        }
+        $parts = explode($this->delimiter, str_replace('.php', '', $this->template));
+        $templates[] = array_shift($parts);
+        foreach ($parts as $i => $part) {
+            $templates[] = $templates[$i] . $this->delimiter . $part;
+        }
+        if ($this->main) {
+            $templates = array_merge($templates, array_map(function ($template) {
+                return $template . $this->delimiter . basename($this->main, '.php');
+            }, $templates));
+        }
+        $templates = array_map(function ($template) {
+            return $template . '.php';
+        }, $templates);
+        return $this->cache('parts', array_reverse($templates));
+    }
+
+    /**
+     * Passes $this->parts() to locate_template() to retrieve template location
+     * @return string Location of template
+     */
+    public function path()
+    {
+        if (!$path = $this->cache('path')) {
+            $path = $this->cache('path', locate_template($this->parts()));
+        }
+        return apply_filters('sage/partial_' . basename($path, '.php'), $path, $this->parts()) ?: $path;
+    }
+
+    protected function cache($key, $value = null)
+    {
+        if ($value !== null) {
+            self::$cache[$this->template][$key] = $value;
+        }
+        return isset(self::$cache[$this->template][$key]) ? self::$cache[$this->template][$key] : null;
+    }
+}
diff --git a/src/lib/Sage/Template/Wrapper.php b/src/lib/Sage/Template/Wrapper.php
index 83db685..58d6399 100644
--- a/src/lib/Sage/Template/Wrapper.php
+++ b/src/lib/Sage/Template/Wrapper.php
@@ -37,24 +37,24 @@ class Wrapper implements WrapperInterface
      */
     public function __toString()
     {
-        return $this->getTemplate();
+        return $this->unwrap();
     }
 
     /** {@inheritdoc} */
-    public function getWrapper()
+    public function wrap()
     {
         $wrappers = apply_filters('sage/wrap_' . $this->slug, $this->wrapper) ?: $this->wrapper;
         return locate_template($wrappers);
     }
 
     /** {@inheritdoc} */
-    public function getSlug()
+    public function slug()
     {
         return $this->slug;
     }
 
     /** {@inheritdoc} */
-    public function getTemplate()
+    public function unwrap()
     {
         $template = apply_filters('sage/unwrap_' . $this->slug, $this->template) ?: $this->template;
         return locate_template($template) ?: $template;
diff --git a/src/lib/Sage/Template/WrapperCollection.php b/src/lib/Sage/Template/WrapperCollection.php
deleted file mode 100644
index 06437d3..0000000
--- a/src/lib/Sage/Template/WrapperCollection.php
+++ /dev/null
@@ -1,81 +0,0 @@
-<?php namespace Roots\Sage\Template;
-
-/**
- * Class Wrapper
- * @package Roots\Sage
- * @author QWp6t
- */
-class WrapperCollection
-{
-    /** @var $this */
-    protected static $instance;
-    /** @var WrapperInterface[] $wrappers */
-    protected $wrappers = [];
-
-    /** Singleton */
-    // @codingStandardsIgnoreStart
-    private function __construct() {}
-    private function __clone() {}
-    // @codingStandardsIgnoreEnd
-
-    /**
-     * @return static
-     */
-    public static function instance()
-    {
-        isset(self::$instance) || self::$instance = new static;
-        return self::$instance;
-    }
-
-    /**
-     * @param WrapperInterface $wrapper
-     * @param string $slug
-     * @return $this
-     * @throws \Exception
-     */
-    public static function add(WrapperInterface $wrapper, $slug = '')
-    {
-        $slug = $slug ?: $wrapper->getSlug();
-        if (self::instance()->exists($slug)) {
-            throw new \Exception("Wrapper $slug already exists.");
-        }
-        self::instance()->wrappers[$slug] = $wrapper;
-        return self::instance();
-    }
-
-    /**
-     * @param string $slug
-     * @return $this
-     */
-    public static function remove($slug)
-    {
-        unset(self::instance()->wrappers[$slug]);
-        return self::instance();
-    }
-
-    /**
-     * @param string $slug
-     * @return null|WrapperInterface
-     */
-    public static function get($slug)
-    {
-        return isset(self::instance()->wrappers[$slug]) ? self::instance()->wrappers[$slug] : null;
-    }
-
-    /**
-     * @return string[] Slugs of wrappers in collection
-     */
-    public static function wrappers()
-    {
-        return array_keys(self::instance()->wrappers);
-    }
-
-    /**
-     * @param $slug
-     * @return bool
-     */
-    public static function exists($slug)
-    {
-        return isset(self::instance()->wrappers[$slug]);
-    }
-}
diff --git a/src/lib/Sage/Template/WrapperInterface.php b/src/lib/Sage/Template/WrapperInterface.php
index 9f8d39b..eaf4e1a 100644
--- a/src/lib/Sage/Template/WrapperInterface.php
+++ b/src/lib/Sage/Template/WrapperInterface.php
@@ -13,15 +13,15 @@ interface WrapperInterface
      *
      * @return string Wrapper template (FQPN of, e.g., `base-page.php`, `base.php`)
      */
-    public function getWrapper();
+    public function wrap();
 
     /**
      * @return string Wrapped template (FQPN of, e.g., `page.php`, `single.php`, `singular.php`)
      */
-    public function getTemplate();
+    public function unwrap();
 
     /**
      * @return string Slug of the WrapperInterface; e.g., `base`
      */
-    public function getSlug();
+    public function slug();
 }
diff --git a/templates/layouts/base.php b/templates/layouts/base.php
index 7d7346e..6fb81b0 100644
--- a/templates/layouts/base.php
+++ b/templates/layouts/base.php
@@ -14,11 +14,11 @@
     <div class="wrap container" role="document">
       <div class="content row">
         <main class="main">
-          <?php include App\template_unwrap(); ?>
+          <?php include App\template()->main(); ?>
         </main><!-- /.main -->
         <?php if (App\display_sidebar()) : ?>
           <aside class="sidebar">
-            <?php get_template_part('partials/sidebar'); ?>
+            <?php App\template_part('partials/sidebar'); ?>
           </aside><!-- /.sidebar -->
         <?php endif; ?>
       </div><!-- /.content -->