import os
import pygame
import sys
import random

pygame.init()

vec = pygame.math.Vector2
HEIGHT = 450
WIDTH = 400
ACC = 0.5
FRIC = -0.12
FPS = 60
PLAYER_SIZE = (30, 30)

FramePerSec = pygame.time.Clock()
displaysurface = pygame.display.set_mode((WIDTH, HEIGHT))
pygame.display.set_caption("Cat Platformer")

# Background loading
bg_frames = []
bg_folder = "bg_frames"
if os.path.exists(bg_folder):
    for filename in sorted(os.listdir(bg_folder)):
        if filename.endswith(('.png', '.jpg', '.gif')):
            frame = pygame.image.load(os.path.join(bg_folder, filename)).convert()
            frame = pygame.transform.scale(frame, (WIDTH, HEIGHT))
            bg_frames.append(frame)
else:
    print("Missing background frames.")
    sys.exit()

bg_frame_index = 0
bg_frame_delay = 5
bg_timer = 0

# --- Load Skins ---
skins_folder = "skins"
skin_files = sorted([f for f in os.listdir(skins_folder) if f.endswith(('.png', '.gif'))])
CHARACTER_IMAGES = [pygame.transform.scale(pygame.image.load(os.path.join(skins_folder, f)).convert_alpha(), PLAYER_SIZE) for f in skin_files]

# Unlock System
unlocked_skins = [0]  # only first skin unlocked by default
unlocked_levels = [0]  # only first level unlocked by default

def update_background():
    global bg_timer, bg_frame_index
    bg_timer += 1
    if bg_timer >= bg_frame_delay:
        bg_timer = 0
        bg_frame_index = (bg_frame_index + 1) % len(bg_frames)
    displaysurface.blit(bg_frames[bg_frame_index], (0, 0))

def draw_text(text, font_size, color, center):
    font = pygame.font.SysFont("Verdana", font_size)
    surface = font.render(text, True, color)
    rect = surface.get_rect(center=center)
    displaysurface.blit(surface, rect)

def quest_menu():
    while True:
        update_background()
        draw_text("Quest Menu", 30, (255, 255, 255), (WIDTH // 2, 40))
        draw_text("Score to unlock skins!", 20, (255, 255, 255), (WIDTH // 2, 100))
        draw_text("ESC to go back", 20, (255, 255, 255), (WIDTH // 2, 400))
        pygame.display.update()
        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                pygame.quit()
                sys.exit()
            if event.type == pygame.KEYDOWN:
                if event.key == pygame.K_ESCAPE:
                    return

def start_screen():
    selected = 0
    cat_spacing = 60
    total_width = cat_spacing * (len(CHARACTER_IMAGES) - 1)
    start_x = WIDTH // 2 - total_width // 2
    play_button = pygame.Rect(WIDTH//2 - 60, 320, 120, 40)
    quest_button = pygame.Rect(WIDTH//2 - 60, 370, 120, 30)

    while True:
        update_background()
        draw_text("Choose Your Cat!", 25, (255, 255, 255), (WIDTH // 2, 30))

        for i in range(len(CHARACTER_IMAGES)):
            x = start_x + i * cat_spacing
            y = 100
            border_rect = pygame.Rect(x - 5, y - 5, PLAYER_SIZE[0] + 10, PLAYER_SIZE[1] + 10)
            if i == selected:
                pygame.draw.rect(displaysurface, (255, 255, 0), border_rect, 3)
            displaysurface.blit(CHARACTER_IMAGES[i], (x, y))
            if i not in unlocked_skins:
                pygame.draw.line(displaysurface, (255, 0, 0), (x, y), (x + PLAYER_SIZE[0], y + PLAYER_SIZE[1]), 2)
                pygame.draw.line(displaysurface, (255, 0, 0), (x + PLAYER_SIZE[0], y), (x, y + PLAYER_SIZE[1]), 2)

        pygame.draw.rect(displaysurface, (50, 200, 50), play_button, border_radius=5)
        draw_text("PLAY", 20, (255, 255, 255), play_button.center)

        pygame.draw.rect(displaysurface, (70, 70, 200), quest_button, border_radius=5)
        draw_text("QUESTS", 18, (255, 255, 255), quest_button.center)

        pygame.display.update()

        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                pygame.quit()
                sys.exit()
            elif event.type == pygame.KEYDOWN:
                if event.key == pygame.K_LEFT:
                    selected = (selected - 1) % len(CHARACTER_IMAGES)
                elif event.key == pygame.K_RIGHT:
                    selected = (selected + 1) % len(CHARACTER_IMAGES)
                elif event.key == pygame.K_RETURN:
                    if selected in unlocked_skins:
                        return selected
            elif event.type == pygame.MOUSEBUTTONDOWN:
                if play_button.collidepoint(event.pos) and selected in unlocked_skins:
                    return selected
                elif quest_button.collidepoint(event.pos):
                    quest_menu()

def level_menu():
    selected = 0
    while True:
        update_background()
        draw_text("Select Level", 30, (255, 255, 255), (WIDTH // 2, 50))
        for i in range(10):
            color = (50, 200, 50) if i in unlocked_levels else (100, 100, 100)
            rect = pygame.Rect(40 + (i % 5) * 65, 120 + (i // 5) * 60, 50, 40)
            pygame.draw.rect(displaysurface, color, rect, border_radius=5)
            draw_text(str(i+1), 20, (0, 0, 0), rect.center)
            if i == selected:
                pygame.draw.rect(displaysurface, (255, 255, 0), rect, 3, border_radius=5)

        pygame.display.update()

        for event in pygame.event.get():
            if event.type == pygame.QUIT:
                pygame.quit()
                sys.exit()
            elif event.type == pygame.KEYDOWN:
                if event.key == pygame.K_LEFT:
                    selected = (selected - 1) % 10
                elif event.key == pygame.K_RIGHT:
                    selected = (selected + 1) % 10
                elif event.key == pygame.K_RETURN:
                    if selected in unlocked_levels:
                        return selected

# Note: You still need to integrate this into the rest of your game loop logic.
# You should call `main_game(level, selected_cat)` and update score tracking to unlock content.