using System;
using System.Collections.Generic;
/*
ConsoleGame: My first console game Snake
*/
namespace ConsoleGame
{
/*
Position: Handle 2D coordinates
*/
public class Position
{
public int left;
public int top;
}
/*
Snake: Handle snake properties and behaviors
*/
public class Snake
{
private int _length = 6;
// snake body positioins
private List<Position> _points = new List<Position>();
public int Length
{
get
{
return _length;
}
set
{
_length = value;
}
}
public List<Position> Points
{
get
{
return _points;
}
set
{
_points = value;
}
}
// Check if the snake is self-overlapped when adding a new position
public bool IfOverlapped(Position currentPos)
{
for (int i = 0; i < _points.Count; i++)
{
if ((_points[i].left == currentPos.left) && (_points[i].top == currentPos.top))
{
return true;
}
}
return false;
}
// Set snake initial position
public Position SetInitialPosition()
{
return new Position()
{
left = 0,
top = 0
};
}
// Clean up the snake body
public void CleanUp()
{
while (_points.Count() > _length)
{
_points.Remove(_points.First());
}
}
}
/*
Food: Handle food properties and behaviors
*/
public class Food
{
private Position? _position = null;
private Random _rnd = new Random();
public Position? Position
{
// get => _position;
get
{
return _position;
}
// set => _position = value;
set
{
_position = value;
}
}
public Random Rnd
{
get
{
return _rnd;
}
set
{
_rnd = value;
}
}
}
class Program
{
// Record if the game is still on-going
private static bool _inPlay = true;
private static int _score = 0;
private static Snake _snake = new Snake();
private static Food _food = new Food();
static void Main(string[] args)
{
Console.CursorVisible = false;
while (_inPlay)
{
if (AcceptInput() || UpdateGame())
DrawScreen();
}
}
private static DateTime nextUpdate = DateTime.MinValue;
// Update objects in the scene
private static bool UpdateGame()
{
if (DateTime.Now < nextUpdate) return false;
if (_food.Position == null)
{
_food.Position = new Position()
{
left = _food.Rnd.Next(Console.WindowWidth),
top = _food.Rnd.Next(Console.WindowHeight)
};
}
if (_lastKey.HasValue)
{
Move(_lastKey.Value);
}
// nextUpdate = DateTime.Now.AddMilliseconds(500);
nextUpdate = DateTime.Now.AddMilliseconds(500 / (_score + 1));
return true;
}
// Draw objects in the scene
private static void DrawScreen()
{
Console.Clear();
// Use the SetCursorPosition method to specify where the next write operation in the console window is to begin
Console.SetCursorPosition(Console.WindowWidth - 3, Console.WindowHeight - 1);
Console.Write(_score);
for (int i = 0; i < _snake.Points.Count; i++)
{
Console.SetCursorPosition(_snake.Points[i].left, _snake.Points[i].top);
Console.Write('*');
}
if (_food.Position != null)
{
Console.SetCursorPosition(_food.Position.left, _food.Position.top);
Console.Write('X');
}
}
static ConsoleKeyInfo? _lastKey;
private static bool AcceptInput()
{
if (!Console.KeyAvailable)
return false;
_lastKey = Console.ReadKey();
return true;
}
// Move the snake based on keyboard
private static void Move(ConsoleKeyInfo key)
{
Position currentPos;
if (_snake.Points.Count != 0)
currentPos = new Position() { left = _snake.Points.Last().left, top = _snake.Points.Last().top };
else
currentPos = _snake.SetInitialPosition();
switch (key.Key)
{
case ConsoleKey.LeftArrow:
currentPos.left--;
break;
case ConsoleKey.RightArrow:
currentPos.left++;
break;
case ConsoleKey.UpArrow:
currentPos.top--;
break;
case ConsoleKey.DownArrow:
currentPos.top++;
break;
default:
// Undefined keys, so the signal should be ignored
break;
}
// Check if the new position collide with scene boundary or self-overlapped
if (DetectCollision(currentPos) == false)
{
_snake.Points.Add(currentPos);
_snake.CleanUp();
}
}
// Handle unexpected cases when a new position is added
private static bool DetectCollision(Position currentPos)
{
// Check if we are off the screen
if (currentPos.top < 0 || currentPos.top > Console.WindowHeight - 1
|| currentPos.left < 0 || currentPos.left > Console.WindowWidth - 1)
{
GameOver();
return true;
}
// Check if we have crashed into the snake body
// if (_snake.Points.Any(p => p.left == currentPos.left && p.top == currentPos.top))
if (_snake.IfOverlapped(currentPos) == true)
{
GameOver();
return true;
}
// Check if we have eaten the food
if ((_food.Position != null) && (_food.Position.left == currentPos.left) && (_food.Position.top == currentPos.top))
{
_snake.Length++;
_score++;
_food.Position = null;
}
return false;
}
// Setting when the game is over
private static void GameOver()
{
_inPlay = false;
Console.Clear();
Console.WriteLine("Game over.");
Console.ReadLine();
// throw new NotImplementedException();
}
}
}
