import fxconv
from PIL import Image, ImageChops

def convert(input, output, params, target):
    recognized = True

    if params["custom-type"] == "animation":
        o = convert_animation(input, params)
    else:
        recognized = False

    if recognized:
        fxconv.elf(o, output, "_" + params["name"], **target)
        return 0
    return 1

def convert_animation(input, params):
    img = Image.open(input)
    frame_count = 0
    image_array = fxconv.ObjectData()
    x_array = bytes()
    y_array = bytes()

    bg = Image.new("RGBA", img.size, (0, 0, 0, 0))

    if not "anchor" in params:
        raise fxconv.FxconvError(f"no anchor specified for {input}")
    x_anchor, y_anchor = map(int, params["anchor"].split(","))

    while 1:
        try:
            img.seek(frame_count)
        except EOFError:
            break

        # Trim image
        nonzero = ImageChops.difference(img.convert("RGBA"), bg)
        bbox = nonzero.getbbox()

        if bbox:
            frame = img.crop(bbox)
            x, y = bbox[0], bbox[1]
        else:
            frame = img.copy()
            x, y = 0, 0

        image_array += fxconv.ptr(fxconv.convert_bopti_cg(frame, params))
        x_array += fxconv.u8(x)
        y_array += fxconv.u8(y)
        frame_count += 1

    o = fxconv.ObjectData()
    o += fxconv.u32(frame_count)
    o += fxconv.ptr(image_array)
    o += fxconv.ptr(x_array)
    o += fxconv.ptr(y_array)
    o += fxconv.u16(x_anchor)
    o += fxconv.u16(y_anchor)
    return o