Use XDG in the same way that Composer does.

Author: greg-1-anderson

README.md

@@ -42,6 +42,8 @@ Option           | Environment Variable | Description
 --base-dir       | CGR_BASE_DIR         | Where to store "global" projects.
 --bin-dir        | CGR_BIN_DIR          | Where to install project binaries.
 
+If these variables are not defined, then cgr uses the value of the `COMPOSER_HOME` environment variable as the base directory to use as described in the [Composer documentation on environment variables](https://getcomposer.org/doc/03-cli.md#composer-home).
+
 To configure cgr to install binaries to ~/bin, add the following to your ~/.bashrc file:
 
 `export CGR_BIN_DIR=$HOME/bin`

bin/cgr.php

@@ -2,10 +2,6 @@
 
 function main($argv)
 {
-    $home = getenv("COMPOSER_HOME");
-    if (empty($home)) {
-        $home = getenv("HOME") . '/.composer';
-    }
     $appRoot = dirname(__DIR__);
 
     if (file_exists($appRoot.'/vendor/autoload.php')) {
@@ -17,6 +13,9 @@ function main($argv)
         exit(1);
     }
 
+    // Find the home directory
+    $home = \Consolidation\Cgr\SystemInformation::getHomeDir();
+
     $app = new \Consolidation\Cgr\Application();
     return $app->run($argv, $home);
 }

src/SystemInformation.php

@@ -0,0 +1,71 @@
+<?php
+
+namespace Consolidation\Cgr;
+
+/**
+ * Determine information about the system
+ */
+class SystemInformation
+{
+    /**
+     * @throws \RuntimeException
+     * @return string
+     */
+    public static function getHomeDir()
+    {
+        $home = getenv('COMPOSER_HOME');
+        if ($home) {
+            return $home;
+        }
+        if (self::isWindows()) {
+            if (!getenv('APPDATA')) {
+                throw new \RuntimeException('The APPDATA or COMPOSER_HOME environment variable must be set for composer to run correctly');
+            }
+            return rtrim(strtr(getenv('APPDATA'), '\\', '/'), '/') . '/Composer';
+        }
+        $userDir = self::getUserDir();
+        if (is_dir($userDir . '/.composer')) {
+            return $userDir . '/.composer';
+        }
+        if (self::useXdg()) {
+            // XDG Base Directory Specifications
+            $xdgConfig = getenv('XDG_CONFIG_HOME') ?: $userDir . '/.config';
+            return $xdgConfig . '/composer';
+        }
+        return $userDir . '/.composer';
+    }
+
+    /**
+     * @return bool Whether the host machine is running a Windows OS
+     */
+    public static function isWindows()
+    {
+        return defined('PHP_WINDOWS_VERSION_BUILD');
+    }
+
+    /**
+     * @return bool
+     */
+    private static function useXdg()
+    {
+        foreach (array_keys($_SERVER) as $key) {
+            if (substr($key, 0, 4) === 'XDG_') {
+                return true;
+            }
+        }
+        return false;
+    }
+
+    /**
+     * @throws \RuntimeException
+     * @return string
+     */
+    private static function getUserDir()
+    {
+        $home = getenv('HOME');
+        if (!$home) {
+            throw new \RuntimeException('The HOME or COMPOSER_HOME environment variable must be set for composer to run correctly');
+        }
+        return rtrim(strtr($home, '\\', '/'), '/');
+    }
+}