from marshmallow import fields
from typing import Optional

from server.utils.images.resolution import set_image_url_resolution_by_mask


class ImageUrlResolutionChangeField(fields.String):
    """Image Url string Field for Marshmallow Schemas usage
    Can replace a resolution format of an image_url if requested and found
    """

    def __init__(
        self,
        change_resolution: bool = True,
        default_resolution_size: int = 640,
        image_size_context_key="image_size",
        *args,
        **kwargs,
    ):
        self._change_resolution = change_resolution
        self._default_resolution_size = default_resolution_size
        self._image_size_context_key = image_size_context_key
        super().__init__(*args, **kwargs)

    def _serialize(self, value, attr, obj, **kwargs) -> Optional[str]:
        field_value = super()._serialize(value, attr, obj, **kwargs)
        if self._change_resolution and isinstance(field_value, str):
            field_value = set_image_url_resolution_by_mask(
                field_value, self.context.get(self._image_size_context_key, self._default_resolution_size)
            )
        return field_value