update

.gitignore

@@ -0,0 +1,4 @@
+.idea/
+vendor/
+js/
+composer.lock

README.md

@@ -1,2 +1,56 @@
-# emitter
-Event emitter component
+# Emitter 
+
+  Event emitter component.
+
+## Installation
+
+```
+$ composer install socketio-php/emitter
+```
+
+## Test
+
+```shell
+➜  emitter git:(master) ✗ php vendor/bin/phpunit tests/EmitterTest.php
+PHPUnit 7.5.20 by Sebastian Bergmann and contributors.
+
+..........                                                        10 / 10 (100%)
+
+Time: 24 ms, Memory: 4.00 MB
+
+OK (10 tests, 10 assertions)
+```
+
+## API
+
+### Emitter#on(event, fn)
+
+  Register an `event` handler `fn`.
+
+### Emitter#once(event, fn)
+
+  Register a single-shot `event` handler `fn`,
+  removed immediately after it is invoked the
+  first time.
+
+### Emitter#off(event, fn)
+
+  * Pass `event` and `fn` to remove a listener.
+  * Pass `event` to remove all listeners on that event.
+  * Pass nothing to remove all listeners on all events.
+
+### Emitter#emit(event, ...)
+
+  Emit an `event` with variable option args.
+
+### Emitter#listeners(event)
+
+  Return an array of callbacks, or an empty array.
+
+### Emitter#hasListeners(event)
+
+  Check if this emitter has `event` handlers.
+
+## License
+
+MIT

composer.json

@@ -0,0 +1,18 @@
+{
+  "name": "socketio-php/emitter",
+  "description": "event emitter",
+  "type": "library",
+  "require": {
+    "php": ">=7.1.22"
+  },
+  "require-dev": {
+    "phpunit/phpunit": "^7.5"
+  },
+  "autoload": {
+    "psr-4": {
+      "Emitter\\": "src/",
+      "EmitterTest\\": "tests/"
+    }
+  },
+  "license": "MIT"
+}

phpunit.xml.dist

@@ -0,0 +1,7 @@
+<phpunit bootstrap="vendor/autoload.php">
+    <testsuites>
+        <testsuite name="parser">
+            <directory>tests</directory>
+        </testsuite>
+    </testsuites>
+</phpunit>

src/Emitter.php

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+<?php
+
+namespace Emitter;
+
+/**
+ * Class Emitter
+ *
+ * @package Emitter
+ */
+class Emitter
+{
+    private $callbacks = [];
+
+    /**
+     * @param string   $event
+     * @param callable $fn
+     *
+     * @return Emitter
+     */
+    public function on(string $event, callable $fn)
+    {
+        return $this->addEventListener($event, $fn);
+    }
+
+    /**
+     * @param string   $event
+     * @param callable $fn
+     *
+     * @return $this
+     */
+    public function addEventListener(string $event, callable $fn)
+    {
+        if (!isset($this->callbacks['$' . $event])) {
+            $this->callbacks['$' . $event] = [];
+        }
+
+        array_push($this->callbacks['$' . $event], $fn);
+
+        return $this;
+    }
+
+    /**
+     * @param string   $event
+     * @param callable $fn
+     *
+     * @return $this
+     */
+    public function once(string $event, callable $fn)
+    {
+        $on = function ($retFn = false) use ($event, $fn) {
+            $arguments = func_get_args();
+            if (is_bool(current($arguments))) {
+                $arguments = array_slice($arguments, 1);
+            }else{
+                $retFn = false;
+            }
+            if (!$retFn) {
+                $this->off($event, $fn);
+                $fn(...$arguments);
+
+                return null;
+            } else {
+                return $fn;
+            }
+        };
+
+        $this->on($event, $on);
+
+        return $this;
+    }
+
+    /**
+     * @param string        $event
+     * @param callable|null $fn
+     *
+     * @return Emitter
+     */
+    public function off(string $event = '', ?callable $fn = null)
+    {
+        return $this->removeListener($event, $fn);
+    }
+
+    /**
+     * @param string        $event
+     * @param callable|null $fn
+     *
+     * @return Emitter
+     */
+    public function removeListener(string $event = '', ?callable $fn = null)
+    {
+        return $this->removeAllListeners($event, $fn);
+    }
+
+    /**
+     * @param string        $event
+     * @param callable|null $fn
+     *
+     * @return Emitter
+     */
+    public function removeAllListeners(string $event = '', ?callable $fn = null)
+    {
+        return $this->removeEventListener($event, $fn);
+    }
+
+    /**
+     * @param string        $event
+     * @param callable|null $fn
+     *
+     * @return $this
+     */
+    public function removeEventListener(string $event = '', ?callable $fn = null)
+    {
+        // all
+        $arguments = func_get_args();
+        $arguments = array_filter($arguments);
+        if (0 === count($arguments)) {
+            $this->callbacks = [];
+
+            return $this;
+        }
+
+
+        if (!isset($this->callbacks['$' . $event])) return $this;
+
+        // specific event
+        $callbacks = $this->callbacks['$' . $event];
+
+        // remove all handlers
+        if (1 == count($arguments)) {
+            unset($this->callbacks['$' . $event]);
+
+            return $this;
+        }
+
+        // remove specific handler
+        $cb = null;
+        for ($i = 0; $i < count($callbacks); $i++) {
+            $cb = $callbacks[$i];
+            if ($cb === $fn || $cb(true) === $fn) {
+                unset($callbacks[$i]);
+                unset($this->callbacks['$' . $event]);
+                break;
+            }
+        }
+
+        return $this;
+    }
+
+    /**
+     * @param string $event
+     */
+    public function emit(string $event)
+    {
+        $arguments = func_get_args();
+        $args = array_slice($arguments, 1);
+        $callbacks = $this->callbacks['$' . $event];
+
+        if (!empty($callbacks)) {
+            for ($i = 0, $len = count($callbacks); $i < $len; ++$i) {
+                $callbacks[$i](...$args);
+            }
+        }
+    }
+
+    /**
+     * @param string $event
+     *
+     * @return array|mixed
+     */
+    public function listeners(string $event)
+    {
+        return $this->callbacks['$' . $event] ?? [];
+    }
+
+    /**
+     * @param string $event
+     *
+     * @return bool
+     */
+    public function hasListeners(string $event)
+    {
+        return count($this->listeners($event)) ? true : false;
+    }
+
+}