added file reader interface

Author: Alexsey-VR

composer.json

@@ -18,7 +18,9 @@
             "src/Gendiff.php",
             "src/CommandInterface.php",
             "src/Command.php",
-            "src/OutputInterface.php"
+            "src/OutputInterface.php",
+            "src/FileReaderInterface.php",
+            "src/FileReader.php"
         ]
     },
     "authors": [

src/Command.php

@@ -4,48 +4,28 @@
 
 use App\CommandInterface;
 use App\OutputInterface;
+use App\FileReaderInterface;
+use App\FileReader;
 
 class ViewFilesCommand implements CommandInterface
 {
-    protected $output;
-    private const MAX_FILE_SIZE = 4096;
+    protected FileReaderInterface $fileReader;
 
-    public function __construct(OutputInterface $output)
+    public function __construct(FileReaderInterface $fileReader)
     {
-        $this->output = $output;
-    }
-
-    private function parseFile(string $filename): array
-    {
-        $handle = fopen($filename, "r");
-        $result = json_decode(fread($handle, self::MAX_FILE_SIZE));
-        fclose($handle);
-        $type = gettype($result);
-        if ($type === 'object') {
-            $keys = (get_object_vars($result));
-        } elseif ($type === 'array') {
-            $keys = array_keys($result);
-        } else {
-            $keys = null;
-        }
-
-        return $keys;
+        $this->fileReader = $fileReader;
     }
 
     public function execute(object $cliData)
     {
         if (isset($cliData['FILE1']) && isset($cliData['FILE2'])) {
-            if (file_exists($cliData['FILE1']) && file_exists($cliData['FILE2'])) {
-                $file1Content = $this->parseFile($cliData['FILE1']);
-                $file2Content = $this->parseFile($cliData['FILE2']);
+            $file1Content = $this->fileReader->readFile($cliData['FILE1']);
+            $file2Content = $this->fileReader->readFile($cliData['FILE2']);
 
-                print_r("File1 content:\n");
-                print_r($file1Content);
-                print_r("File2 content:\n");
-                print_r($file2Content);
-            } else {
-                print_r("File {$cliData['FILE1']} or {$cliData['FILE2']} not exists\n");
-            }
+            print_r("File1 content:\n");
+            print_r($file1Content);
+            print_r("File2 content:\n");
+            print_r($file2Content);
         }
     }
 }

src/FileReader.php

@@ -0,0 +1,29 @@
+<?php
+
+namespace App;
+
+use App\FileReaderInterface;
+
+class FileReader implements FileReaderInterface
+{
+    private const MAX_FILE_SIZE = 4096;
+
+    public function readFile(string $filename): array | null
+    {
+        if (file_exists($filename)) {
+            $handle = fopen($filename, "r");
+            $result = json_decode(fread($handle, self::MAX_FILE_SIZE));
+            fclose($handle);
+            $type = gettype($result);
+            if ($type === 'object') {
+                return (get_object_vars($result));
+            } elseif ($type === 'array') {
+                return array_keys($result);
+            } else {
+                return null;
+            }
+        } else {
+            return null;
+        }
+    }
+}

src/FileReaderInterface.php

@@ -0,0 +1,8 @@
+<?php
+
+namespace App;
+
+interface FileReaderInterface
+{
+    public function readFile(string $filename): array | null;
+}

src/Gendiff.php

@@ -5,6 +5,7 @@
 use Docopt;
 use App\OutputInterface;
 use App\Command;
+use App\FileReader;
 
 function runGendiff(): void
 {
@@ -33,8 +34,9 @@ public function parseCommandData(string $docopt): object
             return Docopt::handle($docopt, array('version' => '1.0.6'));
         }
     };
-    $cliData = $output->parseCommandData($docopt);
 
-    $command = new ViewFilesCommand($output);
+    $fileReader = new FileReader();
+    $cliData = $output->parseCommandData($docopt);
+    $command = new ViewFilesCommand($fileReader);
     $command->execute($cliData);
 }