From bbce5fb19c9d3cef84e3e2c5eeb12e798641384a Mon Sep 17 00:00:00 2001
From: Stanislav Mykhailenko <mykhailenkostanislavzno@gmail.com>
Date: Sun, 9 Apr 2023 22:07:58 +0300
Subject: [PATCH] Add Lesson 4 Task 3

---
 Lesson_4/Task_3/IWorkingWithFile.cs | 22 +++++++
 Lesson_4/Task_3/Program.cs          |  5 ++
 Lesson_4/Task_3/Task_3.csproj       | 10 +++
 Lesson_4/Task_3/WorkingWithFile.cs  | 97 +++++++++++++++++++++++++++++
 4 files changed, 134 insertions(+)
 create mode 100644 Lesson_4/Task_3/IWorkingWithFile.cs
 create mode 100644 Lesson_4/Task_3/Program.cs
 create mode 100644 Lesson_4/Task_3/Task_3.csproj
 create mode 100644 Lesson_4/Task_3/WorkingWithFile.cs

diff --git a/Lesson_4/Task_3/IWorkingWithFile.cs b/Lesson_4/Task_3/IWorkingWithFile.cs
new file mode 100644
index 0000000..4a5a132
--- /dev/null
+++ b/Lesson_4/Task_3/IWorkingWithFile.cs
@@ -0,0 +1,22 @@
+using System;
+using System.Collections.Generic;
+using System.Linq;
+using System.Text;
+using System.Threading.Tasks;
+
+namespace LiskovSubstitution
+{
+    public interface IWorkingWithFile
+    {
+        public string ReadFromFile(string filename);
+        public void WriteToFile(string filename);
+        public void DeleteFile(string filename);
+        public void DownloadFile(string filename);
+        public void CopyFile(string filename);
+        public void GetDataFromFile(string filename);
+        public void CheckFile(string filename);
+        public void SaveToFile(string filename);
+        public Guid CheckRole(Guid role);
+        public Guid CheckUser(Guid user);
+    }
+}
diff --git a/Lesson_4/Task_3/Program.cs b/Lesson_4/Task_3/Program.cs
new file mode 100644
index 0000000..5e5ebe3
--- /dev/null
+++ b/Lesson_4/Task_3/Program.cs
@@ -0,0 +1,5 @@
+using LiskovSubstitution;
+
+(new User()).SaveToFile("test");
+
+(new Administrator()).SaveToFile("test");
diff --git a/Lesson_4/Task_3/Task_3.csproj b/Lesson_4/Task_3/Task_3.csproj
new file mode 100644
index 0000000..f02677b
--- /dev/null
+++ b/Lesson_4/Task_3/Task_3.csproj
@@ -0,0 +1,10 @@
+<Project Sdk="Microsoft.NET.Sdk">
+
+  <PropertyGroup>
+    <OutputType>Exe</OutputType>
+    <TargetFramework>net7.0</TargetFramework>
+    <ImplicitUsings>enable</ImplicitUsings>
+    <Nullable>enable</Nullable>
+  </PropertyGroup>
+
+</Project>
diff --git a/Lesson_4/Task_3/WorkingWithFile.cs b/Lesson_4/Task_3/WorkingWithFile.cs
new file mode 100644
index 0000000..9345e11
--- /dev/null
+++ b/Lesson_4/Task_3/WorkingWithFile.cs
@@ -0,0 +1,97 @@
+namespace LiskovSubstitution
+{
+    public class User : IWorkingWithFile
+    {
+        public virtual Guid Role { get; } = new Guid("a65d9c1d-b8a9-4f4f-be9b-ab03856f33f4");
+
+        public string ReadFromFile(string filename)
+        {
+            return filename;
+        }
+
+        public void WriteToFile(string filename)
+        {
+            Console.WriteLine("Access denied.");
+        }
+
+        public void DeleteFile(string filename)
+        {
+            Console.WriteLine("Access denied.");
+        }
+        
+        public void DownloadFile(string filename)
+        {
+            Console.WriteLine("Downloaded the file.");
+        }
+
+        public void CopyFile(string filename)
+        {
+            Console.WriteLine("Access denied.");
+        }
+        
+        public void GetDataFromFile(string filename)
+        {
+            Console.WriteLine("Got data from the file.");
+        }
+        
+        public void CheckFile(string filename)
+        {
+            Console.WriteLine("Checked the file.");
+        }
+
+        public void SaveToFile(string filename)
+        {
+            Console.WriteLine("Access denied.");
+        }
+
+        public Guid CheckRole(Guid role)
+        {
+            return new Guid("00000000-0000-0000-0000-000000000000");
+        }
+        
+        public Guid CheckUser(Guid user)
+        {
+            return new Guid("00000000-0000-0000-0000-000000000000");
+        }
+    }
+
+    public class Administrator : User
+    {
+        public override Guid Role { get; } = new Guid("c1cfcc4a-e49e-4585-9ccb-265c35321b11");
+
+        public new void WriteToFile(string filename)
+        {
+            Console.WriteLine("Written to the file.");
+        }
+        
+        public new void DeleteFile(string filename)
+        {
+            Console.WriteLine("Deleted the file.");
+        }
+
+        public new void CopyFile(string filename)
+        {
+            Console.WriteLine("Copied the file.");
+        }
+
+        public new void SaveToFile(string filename)
+        {
+            Console.WriteLine("Saved to the file.");
+        }
+    }
+
+    public class Owner : User
+    {
+        public override Guid Role { get; } = new Guid("a157c9cf-c996-46d7-9905-4cd1319a451d");
+
+        public new Guid CheckRole(Guid role)
+        {
+            return role;
+        }
+        
+        public new Guid CheckUser(Guid user)
+        {
+            return user;
+        }
+    }
+}