import os
from PIL import Image

TERRAIN_PATH = "assets/slike/teren"

def expand_image(filename, copies=4):
    path = os.path.join(TERRAIN_PATH, filename)
    if not os.path.exists(path):
        print(f"Skipping {filename}, not found.")
        return

    try:
        img = Image.open(path)
        original_w, original_h = img.size
        
        new_w = original_w * copies
        new_h = original_h * copies
        
        new_img = Image.new('RGBA', (new_w, new_h))
        
        # Tile it
        for x in range(copies):
            for y in range(copies):
                new_img.paste(img, (x * original_w, y * original_h))
                
        output_name = filename.replace(".png", "_atlas.png")
        output_path = os.path.join(TERRAIN_PATH, output_name)
        new_img.save(output_path)
        print(f"✅ Created {output_name} ({new_w}x{new_h})")
        
    except Exception as e:
        print(f"Error expanding {filename}: {e}")

if __name__ == "__main__":
    # Expand main tilesets likely to be used in large maps
    expand_image("grass.png", copies=4) # 512*4 = 2048 (covers GIDs up to ~1700)
    expand_image("dirt.png", copies=4)
    expand_image("stone.png", copies=4)
    expand_image("water.png", copies=4)