import hashlib
import re

try:
    from googleapiclient.errors import HttpError
except ImportError:
    raise ImportError(
        "Google Drive requires extra dependencies. Install with `pip install embedchain[googledrive]`"
    ) from None

from langchain_community.document_loaders import GoogleDriveLoader as Loader
from langchain_community.document_loaders import UnstructuredFileIOLoader

from embedchain.helpers.json_serializable import register_deserializable
from embedchain.loaders.base_loader import BaseLoader


@register_deserializable
class GoogleDriveLoader(BaseLoader):
    @staticmethod
    def _get_drive_id_from_url(url: str):
        regex = r"^https:\/\/drive\.google\.com\/drive\/(?:u\/\d+\/)folders\/([a-zA-Z0-9_-]+)$"
        if re.match(regex, url):
            return url.split("/")[-1]
        raise ValueError(
            f"The url provided {url} does not match a google drive folder url. Example drive url: "
            f"https://drive.google.com/drive/u/0/folders/xxxx"
        )

    def load_data(self, url: str):
        """Load data from a Google drive folder."""
        folder_id: str = self._get_drive_id_from_url(url)

        try:
            loader = Loader(
                folder_id=folder_id,
                recursive=True,
                file_loader_cls=UnstructuredFileIOLoader,
            )

            data = []
            all_content = []

            docs = loader.load()
            for doc in docs:
                all_content.append(doc.page_content)
                # renames source to url for later use.
                doc.metadata["url"] = doc.metadata.pop("source")
                data.append({"content": doc.page_content, "meta_data": doc.metadata})

            doc_id = hashlib.sha256((" ".join(all_content) + url).encode()).hexdigest()
            return {"doc_id": doc_id, "data": data}

        except HttpError:
            raise FileNotFoundError("Unable to locate folder or files, check provided drive URL and try again")