Day-7

#bit.ly/3dC6rF6

import pygame
import random
import math

#INITIALISING PYGAME
pygame.init()

#SCREEN
screen = pygame.display.set_mode((800,600))

#TITLE
pygame.display.set_caption("SPACE INVADERS")

#BACKGROUND
background = pygame.image.load('imgs/background.png')
pygame.mixer.music.load('sounds/background.wav')
pygame.mixer.music.play(-1)

#PLAYER
playerimg = pygame.image.load('imgs/si.png')
pX = 360
pY = 480
pXchange = 0
pYchange = 0
speed = 5
def player(x,y):
    screen.blit(playerimg, (x,y))

#ENEMY
eSound = pygame.mixer.Sound('sounds/explosion.wav')
'''enemyimg = pygame.image.load('imgs/alien.png')
eX = 400
eY = 100
eXchange = 3
eYchange = 3'''
enemyimg = []
eX = []
eY = []
eXchange = []
eYchange = []
num_of_enemies = 5

for i in range(num_of_enemies):
    enemyimg.append(pygame.image.load('imgs/alien.png'))
    eX.append(random.randint(100,700))
    eY.append(random.randint(50,300))
    eXchange.append(3)
    eYchange.append(30)

def enemy(x,y,i):
    screen.blit(enemyimg[i], (x,y))

#BULLET
bSound = pygame.mixer.Sound('sounds/laser.wav')
bulletimg = pygame.image.load('imgs/bullet.png')
bX = pX
bY = pY
bYchange = -10
bState = 0 #READY
def fire_bullet(x,y):
    global bState
    bState = 1 #FIRE
    screen.blit(bulletimg, (x+15,y-30))

#COLLISION DETECTION
def isCollision(EX,EY,BX,BY):
    distance = math.sqrt( (BX-EX)**2 + (BY-EY)**2 )
    if distance < 30:
        return True
    return False

#SCORE
score = 0
font = pygame.font.Font('freesansbold.ttf', 32)
sCoord = (10,10)
def print_score(sc):
    screen.blit(font.render("SCORE: " + str(sc), True, (255,255,255)), sCoord)

#GAME OVER
def game_over_text(sc):
    msg = pygame.font.Font('freesansbold.ttf', 64)
    mCoord = (180,200)
    screen.blit(msg.render("GAME OVER!!", True, (255,255,255)), mCoord)

    fs = pygame.font.Font('freesansbold.ttf', 32)
    fCoord = (280,300)
    screen.blit(fs.render("FINAL SCORE: " + str(sc), True, (255,255,255)), fCoord)


running = True

while running:
    #screen.fill((100,0,200))
    screen.blit(background, (0,0))
    for event in pygame.event.get():
        if event.type == pygame.QUIT:
            running = False

        if event.type == pygame.KEYDOWN:
            if event.key == pygame.K_LEFT: pXchange -= speed
            if event.key == pygame.K_RIGHT: pXchange += speed
            if event.key == pygame.K_UP: pYchange -= speed
            if event.key == pygame.K_DOWN: pYchange += speed
            if event.key == pygame.K_SPACE:
                bSound.play()
                bX,bY = pX, pY
                fire_bullet(bX,bY)

        if event.type == pygame.KEYUP:
            if event.key == pygame.K_LEFT or event.key == pygame.K_RIGHT:
                pXchange = 0
            if event.key == pygame.K_UP or event.key == pygame.K_DOWN:
                pYchange = 0

    '''
    collision = isCollision(eX,eY,bX,bY)
    if collision:
        eSound.play()
        score += 1
        eX = random.randint(100,700)
        eY = random.randint(50,250)
        bState = 0
    '''

    #PLAYER MOVEMENT
    pX += pXchange
    pY += pYchange
    if pX <= 0:
        pX = 800
    elif pX >= 800:
        pX = 0
    if pY < 0:
        pY = 0
    elif pY>536:
        pY = 536
    player(pX,pY)

    #ENEMY MOVEMENT
    for i in range(num_of_enemies):

        #GAME OVER
        if eY[i] > 400:
            for j in range(num_of_enemies):
                eY[j] = 800
            game_over_text(score)
            break


        eX[i] += eXchange[i]
        if eX[i] > 736:
            eY[i] += 30
            eXchange[i] = -eXchange[i]
        if eX[i] < 0:
            eY[i] += 30
            eXchange[i] = -eXchange[i]

        collision = isCollision(eX[i],eY[i],bX,bY)
        if collision:
            eSound.play()
            score += 1
            eX[i] = random.randint(100,700)
            eY[i] = random.randint(50,250)
            bState = 0

        enemy(eX[i],eY[i],i)


    '''
    eX += eXchange
    if eX > 736:
        eY += 30
        eXchange = -eXchange
    elif eX < 0:
        eY += 30
        eXchange = -eXchange
    enemy(eX,eY)
    '''
    #BULLET MOVEMENT
    if bState == 1:
        fire_bullet(bX,bY)
        bY += bYchange
        if bY <= 0:
            bState = 0

    print_score(score)
    pygame.display.update()