enemy.py

import pygame


class Enemy(pygame.sprite.Sprite):
    def __init__(self, health, animation_list, x, y, speed):
        pygame.sprite.Sprite.__init__(self)
        self.alive = True
        self.speed = speed
        self.health = health
        self.last_attack = pygame.time.get_ticks()
        self.attack_cooldown = 1000
        self.animation_list = animation_list
        self.frame_index = 0
        self.action = 0#0==walk, 1==attack, 2==death
        self.update_time = pygame.time.get_ticks()

        #select starting image
        self.image = self.animation_list[self.action][self.frame_index]
        self.rect = pygame.Rect(0, 0, 25, 40)
        self.rect.center = (x, y)


    def update(self, surface, target, bullet_comp):
        if self.alive:
            #check for collision with bullets
            if pygame.sprite.spritecollide(self, bullet_comp, True):
                #lower enemy health
                self.health -= 25

            #check if enemy has reached the castle
            if self.rect.right > target.rect.left -130:
                self.update_action(1)

            #move enemy
            if self.action == 0:
                #update rectangle position
                self.rect.x += self.speed

            #attack
            if self.action == 1:
                #check if enough time has passed since last attack
                if pygame.time.get_ticks() - self.last_attack > self.attack_cooldown:
                    target.health -= 25
                    if target.health < 0:
                        target.health = 0
                    self.last_attack = pygame.time.get_ticks()


            #check if health has dropped to zero
            if self.health <= 0:
                target.money += 100
                target.score += 100
                self.update_action(2)#death
                self.alive = False

        self.update_animation()

        #draw image on screen
        surface.blit(self.image, (self.rect.x - 10, self.rect.y - 15))


    def update_animation(self):
        #define animation cooldown
        animation_cooldown = 250

        #update image depending on current action
        self.image = self.animation_list[self.action][self.frame_index]

        #check if enough time has passed since the last update
        if pygame.time.get_ticks() - self.update_time > animation_cooldown:
            self.update_time = pygame.time.get_ticks()
            self.frame_index += 1

        #if the animation has run out then reset back to the start
        if self.frame_index >= len(self.animation_list[self.action]):
            if self.action == 2:
                self.frame_index = len(self.animation_list[self.action]) - 1
            else:
                self.frame_index = 0


    def update_action(self, new_action):
        #check if the new action is different to the previous one
        if new_action != self.action:
            self.action = new_action
            #update the animation settings
            self.frame_index = 0
            self.update_date = pygame.time.get_ticks()