import os
import hashlib
import mimetypes

from django.core.files.storage import default_storage

from pingcap_sso.file_storage import pingcap_cdn_storage
from pingcap_sso.models import Upload


def upload_file(file_obj, user, is_private=True):
    assert file_obj, 'file_obj can not be empty'
    content_hash = hashlib.sha1(file_obj.read()).hexdigest()
    content_type, _ = mimetypes.guess_type(file_obj.name, strict=False)
    file_path = generate_filepath_by_hash(content_hash)
    _, file_extension = os.path.splitext(file_obj.name)
    if file_extension:
        file_path += file_extension
    file_obj.seek(0)
    file_path = default_storage.save(file_path, file_obj)
    if hasattr(file_obj, 'image'):
        image_width = file_obj.image.width
        image_height = file_obj.image.height
    else:
        image_width = image_height = None
    return Upload.objects.create(
        user=user,
        original_filename=file_obj.name,
        filesize=file_obj.size,
        width=image_width,
        height=image_height,
        path=file_path,
        sha1=content_hash,
        extension=content_type,
        is_private=is_private
    )


def upload_file_to_cdn(file_obj):
    assert file_obj, 'file_obj can not be empty'
    content_hash = hashlib.sha256(file_obj.read()).hexdigest()
    content_type, _ = mimetypes.guess_type(file_obj.name, strict=False)
    file_path = generate_filepath_by_hash(content_hash)
    _, file_extension = os.path.splitext(file_obj.name)
    if file_extension:
        file_path += file_extension
    file_obj.seek(0)
    file_path = pingcap_cdn_storage.save(file_path, file_obj)
    return file_path, pingcap_cdn_storage.url(file_path)


def generate_filepath_by_hash(file_hash):
    return '{}/{}/{}'.format(
        file_hash[0],
        file_hash[1],
        file_hash
    )