From 9c7db7c2913529493d2d3bfced8d3d842ad8bf0e Mon Sep 17 00:00:00 2001
From: Andrew Carter <andrewcarter1992@gmail.com>
Date: Sat, 14 May 2016 11:32:15 +0100
Subject: [PATCH] Split input and output pins

---
 README.md                                     |  41 +++----
 src/GPIO.php                                  |  51 +++++++++
 src/GPIOInterface.php                         |  35 ++++++
 src/{ => Interrupt}/InterruptWatcher.php      |  10 +-
 .../InterruptWatcherInterface.php             |  14 ++-
 src/InterruptWatcherFactory.php               |  32 ------
 src/InterruptWatcherFactoryInterface.php      |  13 ---
 src/Pin/InputPin.php                          |  44 ++++++++
 src/Pin/InputPinInterface.php                 |  25 +++++
 src/Pin/OutputPin.php                         |  33 ++++++
 src/Pin/OutputPinInterface.php                |  13 +++
 src/{ => Pin}/Pin.php                         |  56 +++------
 src/Pin/PinInterface.php                      |  33 ++++++
 src/PinFactory.php                            |  29 -----
 src/PinFactoryInterface.php                   |  15 ---
 src/PinInterface.php                          |  76 -------------
 test/FileSystem/VFS.php                       |  22 ++++
 test/Interrupt/InterruptWatcherTest.php       |  76 +++++++++++++
 test/InterruptWatcherTest.php                 |  57 ----------
 test/Pin/InputPinTest.php                     |  32 ++++++
 test/Pin/OutputPinTest.php                    |  25 +++++
 test/PinTest.php                              | 106 ------------------
 22 files changed, 433 insertions(+), 405 deletions(-)
 create mode 100644 src/GPIO.php
 create mode 100644 src/GPIOInterface.php
 rename src/{ => Interrupt}/InterruptWatcher.php (89%)
 rename src/{ => Interrupt}/InterruptWatcherInterface.php (57%)
 delete mode 100644 src/InterruptWatcherFactory.php
 delete mode 100644 src/InterruptWatcherFactoryInterface.php
 create mode 100644 src/Pin/InputPin.php
 create mode 100644 src/Pin/InputPinInterface.php
 create mode 100644 src/Pin/OutputPin.php
 create mode 100644 src/Pin/OutputPinInterface.php
 rename src/{ => Pin}/Pin.php (65%)
 create mode 100644 src/Pin/PinInterface.php
 delete mode 100644 src/PinFactory.php
 delete mode 100644 src/PinFactoryInterface.php
 delete mode 100644 src/PinInterface.php
 create mode 100644 test/FileSystem/VFS.php
 create mode 100644 test/Interrupt/InterruptWatcherTest.php
 delete mode 100644 test/InterruptWatcherTest.php
 create mode 100644 test/Pin/InputPinTest.php
 create mode 100644 test/Pin/OutputPinTest.php
 delete mode 100644 test/PinTest.php

diff --git a/README.md b/README.md
index 2067646..0be3ef8 100644
--- a/README.md
+++ b/README.md
@@ -13,17 +13,14 @@ A library for low level access to the GPIO pins on a Raspberry Pi
 
 ### Setting Output Pins
 ```php
-use PiPHP\GPIO\PinInterface;
-use PiPHP\GPIO\PinFactory;
+use PiPHP\GPIO\GPIO;
+use PiPHP\GPIO\Pin\PinInterface;
 
-// Retrieve a pin object using the factory class
-$pin = (new PinFactory)->getPin(18);
+// Create a GPIO object
+$gpio = new GPIO();
 
-// Export the pin (so that it is available to use)
-$pin->export();
-
-// Set the pin as an output pin
-$pin->setDirection(PinInterface::DIRECTION_OUT);
+// Retrieve pin 18 and configure it as an output pin
+$pin = $gpio->getOutputPin(18);
 
 // Set the value of the pin high (turn it on)
 $pin->setValue(PinInterface::VALUE_HIGH);
@@ -31,27 +28,23 @@ $pin->setValue(PinInterface::VALUE_HIGH);
 
 ### Input Pin Interrupts
 ```php
-use PiPHP\GPIO\InterruptWatcherFactory;
-use PiPHP\GPIO\PinInterface;
-use PiPHP\GPIO\PinFactory;
-
-// Retrieve a pin object using the factory class
-$pin = (new PinFactory)->getPin(18);
+use PiPHP\GPIO\GPIO;
+use PiPHP\GPIO\Pin\InputPinInterface;
 
-// Export the pin (so that it is available to use)
-$pin->export();
+// Create a GPIO object
+$gpio = new GPIO();
 
-// Set the pin as an input pin
-$pin->setDirection(PinInterface::DIRECTION_IN);
+// Retrieve pin 18 and configure it as an input pin
+$pin = $gpio->getInputPin(18);
 
-// Configure the pin to trigger interrupts on both rising and falling edges
-$pin->setEdge(PinInterface::EDGE_BOTH);
+// Configure interrupts for both rising and falling edges
+$pin->setEdge(InputPinInterface::EDGE_BOTH);
 
-// Create an interrupt watcher using the factory class
-$interruptWatcher = (new InterruptWatcherFactory)->createWatcher();
+// Create an interrupt watcher
+$interruptWatcher = $gpio->createWatcher();
 
 // Register a callback to be triggered on pin interrupts
-$interruptWatcher->register($pin, function (PinInterface $pin, $value) {
+$interruptWatcher->register($pin, function (InputPinInterface $pin, $value) {
     echo 'Pin ' . $pin->getNumber() . ' changed to: ' . $value . PHP_EOL;
 
     // Returning false will make the watcher return false immediately
diff --git a/src/GPIO.php b/src/GPIO.php
new file mode 100644
index 0000000..13a39d4
--- /dev/null
+++ b/src/GPIO.php
@@ -0,0 +1,51 @@
+<?php
+
+namespace PiPHP\GPIO;
+
+use PiPHP\GPIO\FileSystem\FileSystem;
+use PiPHP\GPIO\FileSystem\FileSystemInterface;
+use PiPHP\GPIO\Interrupt\InterruptWatcher;
+use PiPHP\GPIO\Pin\InputPin;
+use PiPHP\GPIO\Pin\OutputPin;
+
+final class GPIO implements GPIOInterface
+{
+    private $fileSystem;
+    private $streamSelect;
+
+    /**
+     * Constructor.
+     * 
+     * @param FileSystemInterface $fileSystem Optional file system object to use
+     * @param callable $streamSelect Optional sream select callable
+     */
+    public function __construct(FileSystemInterface $fileSystem = null, callable $streamSelect = null)
+    {
+        $this->fileSystem = $fileSystem ?: new FileSystem();
+        $this->streamSelect = $streamSelect ?: 'stream_select';
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getInputPin($number)
+    {
+        return new InputPin($this->fileSystem, $number);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getOutputPin($number)
+    {
+        return new OutputPin($this->fileSystem, $number);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function createWatcher()
+    {
+        return new InterruptWatcher($this->fileSystem, $this->streamSelect);
+    }
+}
diff --git a/src/GPIOInterface.php b/src/GPIOInterface.php
new file mode 100644
index 0000000..9cef821
--- /dev/null
+++ b/src/GPIOInterface.php
@@ -0,0 +1,35 @@
+<?php
+
+namespace PiPHP\GPIO;
+
+use PiPHP\GPIO\Interrupt\InterruptWatcherInterface;
+use PiPHP\GPIO\Pin\InputPinInterface;
+use PiPHP\GPIO\Pin\OutputPinInterface;
+
+interface GPIOInterface
+{
+    /**
+     * Get an input pin.
+     * 
+     * @param int $number The pin number
+     * 
+     * @return InputPinInterface
+     */
+    public function getInputPin($number);
+
+    /**
+     * Get an output pin.
+     * 
+     * @param int $number The pin number
+     * 
+     * @return OutputPinInterface
+     */
+    public function getOutputPin($number);
+
+    /**
+     * Create an interrupt watcher.
+     *
+     * @return InterruptWatcherInterface
+     */
+    public function createWatcher();
+}
diff --git a/src/InterruptWatcher.php b/src/Interrupt/InterruptWatcher.php
similarity index 89%
rename from src/InterruptWatcher.php
rename to src/Interrupt/InterruptWatcher.php
index 5a1515e..7034c62 100644
--- a/src/InterruptWatcher.php
+++ b/src/Interrupt/InterruptWatcher.php
@@ -1,8 +1,9 @@
 <?php
 
-namespace PiPHP\GPIO;
+namespace PiPHP\GPIO\Interrupt;
 
 use PiPHP\GPIO\FileSystem\FileSystemInterface;
+use PiPHP\GPIO\Pin\InputPinInterface;
 
 class InterruptWatcher implements InterruptWatcherInterface
 {
@@ -39,13 +40,14 @@ public function __destruct()
     /**
      * {@inheritdoc}
      */
-    public function register(PinInterface $pin, callable $callback)
+    public function register(InputPinInterface $pin, callable $callback)
     {
         $pinNumber = $pin->getNumber();
 
         if (!isset($this->streams[$pinNumber])) {
             $file = '/sys/class/gpio/gpio' . $pinNumber . '/value';
             $this->streams[$pinNumber] = $this->fileSystem->open($file, 'r');
+            stream_set_blocking($this->streams[$pinNumber], false);
         }
 
         $this->pins[$pinNumber] = $pin;
@@ -55,7 +57,7 @@ public function register(PinInterface $pin, callable $callback)
     /**
      * {@inheritdoc}
      */
-    public function unregister(PinInterface $pin)
+    public function unregister(InputPinInterface $pin)
     {
         $pinNumber = $pin->getNumber();
 
@@ -90,7 +92,7 @@ public function watch($timeout)
         $triggers = [];
 
         foreach ($except as $pinNumber => $stream) {
-            $value = fread($stream, 1024);
+            $value = fread($stream, 1);
             @rewind($stream);
 
             if ($value !== false) {
diff --git a/src/InterruptWatcherInterface.php b/src/Interrupt/InterruptWatcherInterface.php
similarity index 57%
rename from src/InterruptWatcherInterface.php
rename to src/Interrupt/InterruptWatcherInterface.php
index e2fe666..c802934 100644
--- a/src/InterruptWatcherInterface.php
+++ b/src/Interrupt/InterruptWatcherInterface.php
@@ -1,23 +1,25 @@
 <?php
 
-namespace PiPHP\GPIO;
+namespace PiPHP\GPIO\Interrupt;
+
+use PiPHP\GPIO\Pin\InputPinInterface;
 
 interface InterruptWatcherInterface
 {
     /**
      * Register a callback to fire on pin interrupts. Only one callback can be registered per pin, this method will overwrite.
      *
-     * @param PinInterface $pin
-     * @param callable     $callback
+     * @param InputPinInterface $pin
+     * @param callable $callback
      */
-    public function register(PinInterface $pin, callable $callback);
+    public function register(InputPinInterface $pin, callable $callback);
 
     /**
      * Unregister a pin callback.
      *
-     * @param PinInterface $pin
+     * @param InputPinInterface $pin
      */
-    public function unregister(PinInterface $pin);
+    public function unregister(InputPinInterface $pin);
 
     /**
      * Watch for pin interrupts.
diff --git a/src/InterruptWatcherFactory.php b/src/InterruptWatcherFactory.php
deleted file mode 100644
index 0e1e046..0000000
--- a/src/InterruptWatcherFactory.php
+++ /dev/null
@@ -1,32 +0,0 @@
-<?php
-
-namespace PiPHP\GPIO;
-
-use PiPHP\GPIO\FileSystem\FileSystem;
-use PiPHP\GPIO\FileSystem\FileSystemInterface;
-
-final class InterruptWatcherFactory implements InterruptWatcherFactoryInterface
-{
-    private $fileSystem;
-    private $streamSelect;
-
-    /**
-     * Constructor.
-     * 
-     * @param FileSystemInterface $fileSystem Optional file system object to use
-     * @param callable $streamSelect The stream select implementation to use
-     */
-    public function __construct(FileSystemInterface $fileSystem = null, $streamSelect = 'stream_select')
-    {
-        $this->fileSystem = $fileSystem ?: new FileSystem();
-        $this->streamSelect = $streamSelect;
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function createWatcher()
-    {
-        return new InterruptWatcher($this->fileSystem, $this->streamSelect);
-    }
-}
diff --git a/src/InterruptWatcherFactoryInterface.php b/src/InterruptWatcherFactoryInterface.php
deleted file mode 100644
index 7000ccc..0000000
--- a/src/InterruptWatcherFactoryInterface.php
+++ /dev/null
@@ -1,13 +0,0 @@
-<?php
-
-namespace PiPHP\GPIO;
-
-interface InterruptWatcherFactoryInterface
-{
-    /**
-     * Create an interrupt watcher.
-     *
-     * @return InterruptWatcherInterface
-     */
-    public function createWatcher();
-}
diff --git a/src/Pin/InputPin.php b/src/Pin/InputPin.php
new file mode 100644
index 0000000..8d81460
--- /dev/null
+++ b/src/Pin/InputPin.php
@@ -0,0 +1,44 @@
+<?php
+
+namespace PiPHP\GPIO\Pin;
+
+use PiPHP\GPIO\FileSystem\FileSystemInterface;
+
+final class InputPin extends Pin implements InputPinInterface
+{
+    const GPIO_PIN_FILE_EDGE = 'edge';
+
+    /**
+     * Constructor.
+     * 
+     * @param FileSystemInterface $fileSystem An object that provides file system access
+     * @param int                 $number     The number of the pin
+     */
+    public function __construct(FileSystemInterface $fileSystem, $number)
+    {
+        $this->fileSystem = $fileSystem;
+        $this->number = $number;
+
+        parent::__construct($fileSystem, $number);
+
+        $this->setDirection(self::DIRECTION_IN);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function getEdge()
+    {
+        $edgeFile = $this->getPinFile(self::GPIO_PIN_FILE_EDGE);
+        return $this->fileSystem->getContents($edgeFile);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function setEdge($edge)
+    {
+        $edgeFile = $this->getPinFile(self::GPIO_PIN_FILE_EDGE);
+        $this->fileSystem->putContents($edgeFile, $edge);
+    }
+}
diff --git a/src/Pin/InputPinInterface.php b/src/Pin/InputPinInterface.php
new file mode 100644
index 0000000..d4223cb
--- /dev/null
+++ b/src/Pin/InputPinInterface.php
@@ -0,0 +1,25 @@
+<?php
+
+namespace PiPHP\GPIO\Pin;
+
+interface InputPinInterface extends PinInterface
+{
+    const EDGE_NONE = 'none';
+    const EDGE_BOTH = 'both';
+    const EDGE_RISING = 'rising';
+    const EDGE_FALLING = 'falling';
+
+    /**
+     * Get the pin edge.
+     * 
+     * @return string The pin edge value
+     */
+    public function getEdge();
+
+    /**
+     * Set the pin edge.
+     * 
+     * @param string $edge The pin edge value to set
+     */
+    public function setEdge($edge);
+}
diff --git a/src/Pin/OutputPin.php b/src/Pin/OutputPin.php
new file mode 100644
index 0000000..4ab3fad
--- /dev/null
+++ b/src/Pin/OutputPin.php
@@ -0,0 +1,33 @@
+<?php
+
+namespace PiPHP\GPIO\Pin;
+
+use PiPHP\GPIO\FileSystem\FileSystemInterface;
+
+final class OutputPin extends Pin implements OutputPinInterface
+{
+    /**
+     * Constructor.
+     * 
+     * @param FileSystemInterface $fileSystem An object that provides file system access
+     * @param int                 $number     The number of the pin
+     */
+    public function __construct(FileSystemInterface $fileSystem, $number)
+    {
+        $this->fileSystem = $fileSystem;
+        $this->number = $number;
+
+        parent::__construct($fileSystem, $number);
+
+        $this->setDirection(self::DIRECTION_OUT);
+    }
+
+    /**
+     * {@inheritdoc}
+     */
+    public function setValue($value)
+    {
+        $valueFile = $this->getPinFile(self::GPIO_PIN_FILE_VALUE);
+        $this->fileSystem->putContents($valueFile, $value);
+    }
+}
diff --git a/src/Pin/OutputPinInterface.php b/src/Pin/OutputPinInterface.php
new file mode 100644
index 0000000..85b75fa
--- /dev/null
+++ b/src/Pin/OutputPinInterface.php
@@ -0,0 +1,13 @@
+<?php
+
+namespace PiPHP\GPIO\Pin;
+
+interface OutputPinInterface extends PinInterface
+{
+    /**
+     * Set the pin value.
+     * 
+     * @param int $value The value to set
+     */
+    public function setValue($value);
+}
diff --git a/src/Pin.php b/src/Pin/Pin.php
similarity index 65%
rename from src/Pin.php
rename to src/Pin/Pin.php
index a84acb7..bd149c1 100644
--- a/src/Pin.php
+++ b/src/Pin/Pin.php
@@ -1,23 +1,26 @@
 <?php
 
-namespace PiPHP\GPIO;
+namespace PiPHP\GPIO\Pin;
 
 use PiPHP\GPIO\FileSystem\FileSystemInterface;
 
-final class Pin implements PinInterface
+abstract class Pin implements PinInterface
 {
     // Paths
-    const GPIO_PATH   = '/sys/class/gpio/';
+    const GPIO_PATH = '/sys/class/gpio/';
     const GPIO_PREFIX = 'gpio';
 
     // Files
-    const GPIO_FILE_EXPORT   = 'export';
+    const GPIO_FILE_EXPORT = 'export';
     const GPIO_FILE_UNEXPORT = 'unexport';
 
     // Pin files
     const GPIO_PIN_FILE_DIRECTION = 'direction';
-    const GPIO_PIN_FILE_VALUE     = 'value';
-    const GPIO_PIN_FILE_EDGE      = 'edge';
+    const GPIO_PIN_FILE_VALUE = 'value';
+
+    // Directions
+    const DIRECTION_IN = 'in';
+    const DIRECTION_OUT = 'out';
 
     private $fileSystem;
     private $number;
@@ -32,6 +35,8 @@ public function __construct(FileSystemInterface $fileSystem, $number)
     {
         $this->fileSystem = $fileSystem;
         $this->number = $number;
+
+        $this->export();
     }
 
     /**
@@ -61,16 +66,7 @@ public function unexport()
     /**
      * {@inheritdoc}
      */
-    public function getDirection()
-    {
-        $directionFile = $this->getPinFile(self::GPIO_PIN_FILE_DIRECTION);
-        return $this->fileSystem->getContents($directionFile);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function setDirection($direction)
+    protected function setDirection($direction)
     {
         $directionFile = $this->getPinFile(self::GPIO_PIN_FILE_DIRECTION);
         $this->fileSystem->putContents($directionFile, $direction);
@@ -85,32 +81,6 @@ public function getValue()
         return (int) $this->fileSystem->getContents($valueFile);
     }
 
-    /**
-     * {@inheritdoc}
-     */
-    public function setValue($value)
-    {
-        $valueFile = $this->getPinFile(self::GPIO_PIN_FILE_VALUE);
-        $this->fileSystem->putContents($valueFile, $value);
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getEdge()
-    {
-        $edgeFile = $this->getPinFile(self::GPIO_PIN_FILE_EDGE);
-        return $this->fileSystem->getContents($edgeFile);
-    }
-    /**
-     * {@inheritdoc}
-     */
-    public function setEdge($edge)
-    {
-        $edgeFile = $this->getPinFile(self::GPIO_PIN_FILE_EDGE);
-        $this->fileSystem->putContents($edgeFile, $edge);
-    }
-
     /**
      * Get the path of the import or export file.
      * 
@@ -130,7 +100,7 @@ private function getFile($file)
      * 
      * @return string
      */
-    private function getPinFile($file)
+    protected function getPinFile($file)
     {
         return self::GPIO_PATH . self::GPIO_PREFIX . $this->getNumber() . '/' . $file;
     }
diff --git a/src/Pin/PinInterface.php b/src/Pin/PinInterface.php
new file mode 100644
index 0000000..3eca7b1
--- /dev/null
+++ b/src/Pin/PinInterface.php
@@ -0,0 +1,33 @@
+<?php
+
+namespace PiPHP\GPIO\Pin;
+
+interface PinInterface
+{
+    const VALUE_LOW = 0;
+    const VALUE_HIGH = 1;
+
+    /**
+     * Get the pin number.
+     * 
+     * @return int
+     */
+    public function getNumber();
+
+    /**
+     * Export the pin.
+     */
+    public function export();
+
+    /**
+     * Unexport the pin.
+     */
+    public function unexport();
+
+    /**
+     * Get the pin value.
+     * 
+     * @return int
+     */
+    public function getValue();
+}
diff --git a/src/PinFactory.php b/src/PinFactory.php
deleted file mode 100644
index 29e086c..0000000
--- a/src/PinFactory.php
+++ /dev/null
@@ -1,29 +0,0 @@
-<?php
-
-namespace PiPHP\GPIO;
-
-use PiPHP\GPIO\FileSystem\FileSystem;
-use PiPHP\GPIO\FileSystem\FileSystemInterface;
-
-final class PinFactory implements PinFactoryInterface
-{
-    private $fileSystem;
-
-    /**
-     * Constructor.
-     * 
-     * @param FileSystemInterface $fileSystem Optional file system object to use
-     */
-    public function __construct(FileSystemInterface $fileSystem = null)
-    {
-        $this->fileSystem = $fileSystem ?: new FileSystem();
-    }
-
-    /**
-     * {@inheritdoc}
-     */
-    public function getPin($number)
-    {
-        return new Pin($this->fileSystem, $number);
-    }
-}
diff --git a/src/PinFactoryInterface.php b/src/PinFactoryInterface.php
deleted file mode 100644
index 939b83c..0000000
--- a/src/PinFactoryInterface.php
+++ /dev/null
@@ -1,15 +0,0 @@
-<?php
-
-namespace PiPHP\GPIO;
-
-interface PinFactoryInterface
-{
-    /**
-     * Get a pin.
-     * 
-     * @param int $number The pin number
-     * 
-     * @return PinInterface
-     */
-    public function getPin($number);
-}
diff --git a/src/PinInterface.php b/src/PinInterface.php
deleted file mode 100644
index ed37ae0..0000000
--- a/src/PinInterface.php
+++ /dev/null
@@ -1,76 +0,0 @@
-<?php
-
-namespace PiPHP\GPIO;
-
-interface PinInterface
-{
-    const DIRECTION_IN  = 'in';
-    const DIRECTION_OUT = 'out';
-
-    const VALUE_LOW  = 0;
-    const VALUE_HIGH = 1;
-
-    const EDGE_NONE    = 'none';
-    const EDGE_BOTH    = 'both';
-    const EDGE_RISING  = 'rising';
-    const EDGE_FALLING = 'falling';
-
-    /**
-     * Get the pin number.
-     * 
-     * @return int
-     */
-    public function getNumber();
-
-    /**
-     * Export the pin.
-     */
-    public function export();
-
-    /**
-     * Unexport the pin.
-     */
-    public function unexport();
-
-    /**
-     * Get the pin direction.
-     * 
-     * @return string
-     */
-    public function getDirection();
-
-    /**
-     * Set the pin direction.
-     * 
-     * @param string $direction The direction to set
-     */
-    public function setDirection($direction);
-
-    /**
-     * Get the pin value.
-     * 
-     * @return int
-     */
-    public function getValue();
-
-    /**
-     * Set the pin value.
-     * 
-     * @param int $value The value to set
-     */
-    public function setValue($value);
-
-    /**
-     * Get the pin edge.
-     * 
-     * @return string The pin edge value
-     */
-    public function getEdge();
-
-    /**
-     * Set the pin edge.
-     * 
-     * @param string $edge The pin edge value to set
-     */
-    public function setEdge($edge);
-}
diff --git a/test/FileSystem/VFS.php b/test/FileSystem/VFS.php
new file mode 100644
index 0000000..86d5b02
--- /dev/null
+++ b/test/FileSystem/VFS.php
@@ -0,0 +1,22 @@
+<?php
+
+namespace PiPHP\Test\GPIO\FileSystem;
+
+use PiPHP\GPIO\FileSystem\FileSystemInterface;
+
+class VFS implements FileSystemInterface
+{
+    private $vfs = [];
+
+    public function open($path, $mode) {}
+
+    public function getContents($path)
+    {
+        return $this->vfs[$path];
+    }
+
+    public function putContents($path, $buffer)
+    {
+        $this->vfs[$path] = $buffer;
+    }
+}
diff --git a/test/Interrupt/InterruptWatcherTest.php b/test/Interrupt/InterruptWatcherTest.php
new file mode 100644
index 0000000..bd9651e
--- /dev/null
+++ b/test/Interrupt/InterruptWatcherTest.php
@@ -0,0 +1,76 @@
+<?php
+
+namespace PiPHP\Test\GPIO;
+
+use PiPHP\GPIO\GPIO;
+use PiPHP\GPIO\FileSystem\FileSystemInterface;
+
+class InterruptWatcherTest extends \PHPUnit_Framework_TestCase
+{
+    public function testWatcher()
+    {
+        $streamPair2 = stream_socket_pair(STREAM_PF_UNIX, STREAM_SOCK_STREAM, STREAM_IPPROTO_IP);
+        $streamPair3 = stream_socket_pair(STREAM_PF_UNIX, STREAM_SOCK_STREAM, STREAM_IPPROTO_IP);
+
+        $fileSystem = $this
+            ->getMockBuilder(FileSystemInterface::class)
+            ->setMethods(['open', 'getContents', 'putContents'])
+            ->getMock();
+
+        $map = [
+            ['/sys/class/gpio/gpio2/value', 'r', $streamPair2[0]],
+            ['/sys/class/gpio/gpio3/value', 'r', $streamPair3[0]],
+        ];
+
+        $fileSystem->method('open')
+            ->will($this->returnValueMap($map));
+
+        // Maps $except to $read for testing
+        $streamSelect = function ($read, $write, $except) {
+            $dummy = [];
+            return stream_select($except, $write, $dummy);
+        };
+
+        $gpio = new GPIO($fileSystem, $streamSelect);
+        $watcher = $gpio->createWatcher();
+
+        $callCount2 = $callCount3 = 0;
+
+        $pin2 = $gpio->getInputPin(2);
+        $pin3 = $gpio->getInputPin(3);
+
+        $watcher->register($pin2, function ($pin, $value) use (&$callCount2, $pin2) {
+            $callCount2++;
+            $this->assertSame($pin2, $pin);
+            $this->assertEquals(1, $value);
+
+            return true;
+        });
+
+        $watcher->register($pin3, function ($pin, $value) use (&$callCount3, $pin3) {
+            $callCount3++;
+            $this->assertSame($pin3, $pin);
+            $this->assertEquals(0, $value);
+
+            return true;
+        });
+
+        fwrite($streamPair2[1], '1');
+        $watcher->watch(100);
+
+        fwrite($streamPair2[1], '1');
+        fwrite($streamPair3[1], '0');
+        $watcher->watch(100);
+
+        $watcher->unregister($pin2);
+
+        @fwrite($streamPair2[1], '0');
+        $watcher->watch(100);
+
+        $this->assertEquals(2, $callCount2);
+        $this->assertEquals(3, $callCount3);
+
+        fclose($streamPair2[1]);
+        fclose($streamPair3[1]);
+    }
+}
diff --git a/test/InterruptWatcherTest.php b/test/InterruptWatcherTest.php
deleted file mode 100644
index 1b23c0f..0000000
--- a/test/InterruptWatcherTest.php
+++ /dev/null
@@ -1,57 +0,0 @@
-<?php
-
-namespace PiPHP\Test\GPIO;
-
-use PiPHP\GPIO\InterruptWatcherFactory;
-use PiPHP\GPIO\FileSystem\FileSystemInterface;
-use PiPHP\GPIO\PinFactory;
-
-class InterruptWatcherTest extends \PHPUnit_Framework_TestCase
-{
-    public function testWatcher()
-    {
-        $streamPair = stream_socket_pair(STREAM_PF_UNIX, STREAM_SOCK_STREAM, STREAM_IPPROTO_IP);
-
-        $fileSystem = $this
-            ->getMockBuilder(FileSystemInterface::class)
-            ->setMethods(['open', 'getContents', 'putContents'])
-            ->getMock();
-
-        $fileSystem->expects($this->once())
-            ->method('open')
-            ->with('/sys/class/gpio/gpio2/value', 'r')
-            ->willReturn($streamPair[0]);
-
-        // Maps $except to $read for testing
-        $streamSelect = function ($read, $write, $except) {
-            $dummy = [];
-            return stream_select($except, $write, $dummy);
-        };
-
-        $watcherFactory = new InterruptWatcherFactory($fileSystem, $streamSelect);
-        $watcher = $watcherFactory->createWatcher();
-
-        $callCount = 0;
-        $expectedPin = (new PinFactory)->getPin(2);
-
-        $watcher->register($expectedPin, function ($pin, $value) use (&$callCount, $expectedPin) {
-            $callCount++;
-            $this->assertSame($expectedPin, $pin);
-            $this->assertEquals(1, $value);
-        });
-
-        fwrite($streamPair[1], '1');
-        $watcher->watch(100);
-        fwrite($streamPair[1], '1');
-        $watcher->watch(100);
-
-        $watcher->unregister($expectedPin);
-
-        @fwrite($streamPair[1], '0');
-        $watcher->watch(100);
-
-        $this->assertEquals(2, $callCount);
-
-        fclose($streamPair[1]);
-    }
-}
diff --git a/test/Pin/InputPinTest.php b/test/Pin/InputPinTest.php
new file mode 100644
index 0000000..0bce449
--- /dev/null
+++ b/test/Pin/InputPinTest.php
@@ -0,0 +1,32 @@
+<?php
+
+namespace PiPHP\Test\GPIO\Pin;
+
+use PiPHP\GPIO\GPIO;
+use PiPHP\Test\GPIO\FileSystem\VFS;
+
+class InputPinTest extends \PHPUnit_Framework_TestCase
+{
+    public function testInputPin()
+    {
+        $vfs = new VFS();
+        $gpio = new GPIO($vfs);
+
+        $pin = $gpio->getInputPin(2);
+
+        $this->assertEquals('2', $vfs->getContents('/sys/class/gpio/export'));
+        $this->assertEquals('in', $vfs->getContents('/sys/class/gpio/gpio2/direction'));
+ 
+        $pin->setEdge('both');
+
+        $this->assertEquals('both', $pin->getEdge());
+        $this->assertEquals('both', $vfs->getContents('/sys/class/gpio/gpio2/edge'));
+
+        $vfs->putContents('/sys/class/gpio/gpio2/value', '1');
+
+        $this->assertEquals(1, $pin->getValue());
+
+        $pin->unexport();
+        $this->assertEquals('2', $vfs->getContents('/sys/class/gpio/unexport'));
+    }
+}
diff --git a/test/Pin/OutputPinTest.php b/test/Pin/OutputPinTest.php
new file mode 100644
index 0000000..59778a3
--- /dev/null
+++ b/test/Pin/OutputPinTest.php
@@ -0,0 +1,25 @@
+<?php
+
+namespace PiPHP\Test\GPIO\Pin;
+
+use PiPHP\GPIO\GPIO;
+use PiPHP\Test\GPIO\FileSystem\VFS;
+
+class OutputPinTest extends \PHPUnit_Framework_TestCase
+{
+    public function testOutputPin()
+    {
+        $vfs = new VFS();
+        $gpio = new GPIO($vfs);
+
+        $pin = $gpio->getOutputPin(2);
+
+        $this->assertEquals('2', $vfs->getContents('/sys/class/gpio/export'));
+        $this->assertEquals('out', $vfs->getContents('/sys/class/gpio/gpio2/direction'));
+ 
+        $pin->setValue(1);
+
+        $this->assertEquals(1, $vfs->getContents('/sys/class/gpio/gpio2/value'));
+        $this->assertEquals(1, $pin->getValue());
+    }
+}
diff --git a/test/PinTest.php b/test/PinTest.php
deleted file mode 100644
index de90f5c..0000000
--- a/test/PinTest.php
+++ /dev/null
@@ -1,106 +0,0 @@
-<?php
-
-namespace PiPHP\Test\GPIO;
-
-use PiPHP\GPIO\FileSystem\FileSystemInterface;
-use PiPHP\GPIO\Pin;
-use PiPHP\GPIO\PinFactory;
-
-class PinTest extends \PHPUnit_Framework_TestCase
-{
-    const TEST_PIN_NUMBER = 5;
-
-    public function testGetNumber()
-    {
-        $pin = $this->getPin();
-        $this->assertEquals(self::TEST_PIN_NUMBER, $pin->getNumber());
-    }
-
-    public function testDirection()
-    {
-        $pin = $this->getPin('/sys/class/gpio/gpio' . self::TEST_PIN_NUMBER . '/direction');
-        $pin->setDirection(Pin::DIRECTION_IN);
-        $this->assertEquals(Pin::DIRECTION_IN, $pin->getDirection());
-    }
-
-    public function testValue()
-    {
-        $pin = $this->getPin('/sys/class/gpio/gpio' . self::TEST_PIN_NUMBER . '/value');
-        $pin->setValue(Pin::VALUE_HIGH);
-        $this->assertEquals(Pin::VALUE_HIGH, $pin->getValue());
-    }
-
-    public function testEdge()
-    {
-        $pin = $this->getPin('/sys/class/gpio/gpio' . self::TEST_PIN_NUMBER . '/edge');
-        $pin->setEdge(Pin::EDGE_RISING);
-        $this->assertEquals(Pin::EDGE_RISING, $pin->getEdge());
-    }
-
-    private function getPin($expectedFile = null)
-    {
-        $mockFileSystem = new FileSystemMock($expectedFile);
-        return (new PinFactory($mockFileSystem))->getPin(self::TEST_PIN_NUMBER);
-    }
-
-    public function testExport()
-    {
-        $exportFile = '/sys/class/gpio/export';
-
-        $mockFileSystem = new FileSystemMock($exportFile);
-        $pin = (new PinFactory($mockFileSystem))->getPin(self::TEST_PIN_NUMBER);
-        $pin->export();
-
-        $this->assertEquals(self::TEST_PIN_NUMBER, $mockFileSystem->getContents($exportFile));
-    }
-
-    public function testUnexport()
-    {
-        $unexportFile = '/sys/class/gpio/unexport';
-
-        $mockFileSystem = new FileSystemMock($unexportFile);
-        $pin = (new PinFactory($mockFileSystem))->getPin(self::TEST_PIN_NUMBER);
-        $pin->unexport();
-
-        $this->assertEquals(self::TEST_PIN_NUMBER, $mockFileSystem->getContents($unexportFile));
-    }
-}
-
-class FileSystemMock implements FileSystemInterface
-{
-    private $expectedFile;
-    private $contents;
-
-    public function __construct($expectedFile)
-    {
-        $this->expectedFile = $expectedFile;
-        $this->contents = null;
-    }
-
-    public function open($path, $mode)
-    {
-    }
-
-    public function getContents($path)
-    {
-        $this->checkExpectedFile($path);
-
-        return $this->contents;
-    }
-
-    public function putContents($path, $buffer, $flags = 0)
-    {
-        $this->checkExpectedFile($path);
-
-        $this->contents = $buffer;
-
-        return strlen($buffer);
-    }
-
-    private function checkExpectedFile($path)
-    {
-        if ($this->expectedFile !== $path) {
-            throw new \InvalidArgumentException('Expected ' . $this->expectedFile . ' got ' . $path);
-        }
-    }
-}