snake.py

from random import choice
from threading import Thread
import sys
import select
import tty
import termios

class Snake:
    
    def __init__(self, length, pos, direction, board_size):
    
        if length != len(pos):
            raise Exception("Length is not equal to the size of `pos`")
        self.len    = length
        self.pos    = pos
        self.dir    = direction
        self.last   = pos[-1]
        self.first  = pos[0]
        self.columns= board_size[0]
        self.rows   = board_size[1]
        self.init_l = length
        self.status = True

    def normalize_pos(self):
        return [ [p[0]%self.rows, p[1]%self.columns] for p in self.pos]

    def move_toward_direction(self, step = 1, increment_size=False):

        temp = self.last[:]
        if self.dir.upper() == "UP":
            temp[0] -= 1
            if self.check(temp):
                self.pos.append(temp)
            else:
                self.__lost()

        elif self.dir.upper() == "DOWN":
            temp[0] += 1
            if self.check(temp):
                self.pos.append(temp)
            else:
                self.__lost()

        elif self.dir.upper() == "RIGHT":
            temp[1] += 1
            """
            if temp[1] >= self.columns:
                temp[1] = 0
            elif temp[1] <= 0:
                temp[1] = self.columns-1
            """
            if self.check(temp):
                self.pos.append(temp)
            else:
                self.__lost()

        elif self.dir.upper() == "LEFT":
            temp[1] -= 1
            """
            if temp[1] >= self.columns:
                temp[1] = 0
            elif temp[1] <= 0:
                temp[1] = self.columns-1
            """
            if self.check(temp):
                self.pos.append(temp)
            else:
                self.__lost()
        
        else:
            raise Exception(f"Direction not correct!: {self.dir}")

        if not increment_size :
            self.pos.remove(self.first)
            self.first = self.pos[0]
        else:
            self.len += 1
        self.first = self.pos[0]
        self.last  = self.pos[-1]

        
    
    def check(self, tmp):
        
        if tmp not in self.normalize_pos() and tmp not in self.pos:
            return True
        else:
            return False

    def rand_direction(self):
        
        counter = 0

        while True:
            
            tmp = choice(["UP","RIGHT","LEFT","DOWN"])
            #chcs = [i for i in ["UP","RIGHT","LEFT","DOWN"] if self.check(i)]
            temp = self.last[:]
            if tmp == "UP"     :
                temp[0] -= 1

            elif tmp == "DOWN" :
                temp[0] += 1

            elif tmp == "RIGHT":
                temp[1] += 1

            elif tmp == "LEFT" :
                temp[1] -= 1

            else:
                raise Exception(f"Direction not correct!: {tmp}")
     
            if self.check(temp):
                self.dir = tmp
                return
            counter += 1
            if counter > 32:
                raise Exception("No movement is possible")


    def check_arrow_keys(self):
        old_settings = termios.tcgetattr(sys.stdin)
        try:
            tty.setcbreak(sys.stdin.fileno())
            while 1:
                if self.__isData() or self.status:
                    c = sys.stdin.read(3)
                    # Up Arrow Key Pressed
                    if c == '\x1b[A':         
                        if self.dir != "DOWN":
                            self.dir = "UP"
                    # Down Arrow Key Pressed
                    elif c == '\x1b[B':
                        if self.dir != "UP":
                            self.dir = "DOWN"
                    # Left Arrow Key Pressed
                    elif c == '\x1b[D':
                        if self.dir != "RIGHT":
                            self.dir = "LEFT"
                    # Right Arrow Key Pressed
                    elif c == '\x1b[C':
                        if self.dir != "LEFT":
                            self.dir = "RIGHT"
                    else:
                        # TODO: Clear Input Buffer If Arrow Key NOT Pressed to Keep Game Running 
                        pass
                else:
                    return

        finally:
            termios.tcsetattr(sys.stdin, termios.TCSADRAIN, old_settings)
                
    def __isData(self):
        return select.select([sys.stdin], [], [], 0) == ([sys.stdin], [], [])

    def __lost(self):
        self.status = False
        #print(f"You lost the game with score {score}")
        #raise Exception(f"You lost the game with score {score}")