from enum import Enum
from typing import Optional, List

from pydantic import BaseModel
from fatcat_openapi_client import ReleaseEntity


class AccessType(str, Enum):
    """describes type of access URL"""

    wayback = "wayback"
    ia_file = "ia_file"
    ia_microfilm = "ia_microfilm"
    repository = "repository"
    openlibrary = "openlibrary"
    wikipedia = "wikipedia"

class AccessOption(BaseModel):

    access_type: AccessType

    # note: for `target_url` refs, would do a CDX lookup and this URL would be
    # a valid/HTTP-200 web.archive.org capture URL
    access_url: str

    # application/pdf, text/html, etc
    # blank for landing pages
    mimetype: Optional[str]

    size_bytes: Optional[int]
    thumbnail_url: Optional[str]


def release_access_options(release: ReleaseEntity) -> List[AccessOption]:
    """
    Extracts access options from a release.

    TODO: proper implementation and filtering, instead of just returning first
    option found
    """
    options = []
    for f in (release.files or []):
        thumbnail_url = None
        if f.mimetype == 'application/pdf' and f.sha1 and f.urls:
            # NOTE: scholar.archive.org does an actual database check before
            # generating these URLs, but we skip that for speed
            thumbnail_url = f"https://blobs.fatcat.wiki/thumbnail/pdf/{f.sha1[0:2]}/{f.sha1[2:4]}/{f.sha1}.180px.jpg"
        for u in (f.urls or []):
            if '://web.archive.org/' in u.url:
                return [AccessOption(
                    access_type="wayback",
                    access_url=u.url,
                    mimetype=f.mimetype,
                    size_bytes=f.size,
                    thumbnail_url=thumbnail_url,
                )]
            elif '://archive.org/' in u.url:
                return [AccessOption(
                    access_type="ia_file",
                    access_url=u.url,
                    mimetype=f.mimetype,
                    size_bytes=f.size,
                    thumbnail_url=thumbnail_url,
                )]
    return options