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#

# Source code for langchain.document_loaders.blackboard

    """Loader that loads all documents from a blackboard course."""
    import contextlib
    import re
    from pathlib import Path
    from typing import Any, List, Optional, Tuple
    from urllib.parse import unquote

    from langchain.docstore.document import Document
    from langchain.document_loaders.directory import DirectoryLoader
    from langchain.document_loaders.pdf import PyPDFLoader
    from langchain.document_loaders.web_base import WebBaseLoader

    class BlackboardLoader(WebBaseLoader):
        """Loader that loads all documents from a Blackboard course.

        This loader is not compatible with all Blackboard courses. It is only
        compatible with courses that use the new Blackboard interface.
        To use this loader, you must have the BbRouter cookie. You can get this
        cookie by logging into the course and then copying the value of the
        BbRouter cookie from the browser's developer tools.

        Example:
            .. code-block:: python

                from langchain.document_loaders import BlackboardLoader

                loader = BlackboardLoader(
                    blackboard_course_url="https://blackboard.example.com/webapps/blackboard/execute/announcement?method=search&context=course_entry&course_id=_123456_1",
                    bbrouter="expires:12345...",
                )
                documents = loader.load()

        """

        base_url: str
        folder_path: str
        load_all_recursively: bool

        def __init__(
            self,
            blackboard_course_url: str,
            bbrouter: str,
            load_all_recursively: bool = True,
            basic_auth: Optional[Tuple[str, str]] = None,
            cookies: Optional[dict] = None,
        ):
            """Initialize with blackboard course url.

            The BbRouter cookie is required for most blackboard courses.

            Args:
                blackboard_course_url: Blackboard course url.
                bbrouter: BbRouter cookie.
                load_all_recursively: If True, load all documents recursively.
                basic_auth: Basic auth credentials.
                cookies: Cookies.

            Raises:
                ValueError: If blackboard course url is invalid.
            """
            super().__init__(blackboard_course_url)
            # Get base url
            try:
                self.base_url = blackboard_course_url.split("/webapps/blackboard")[0]
            except IndexError:
                raise ValueError(
                    "Invalid blackboard course url. "
                    "Please provide a url that starts with "
                    "https://<blackboard_url>/webapps/blackboard"
                )
            if basic_auth is not None:
                self.session.auth = basic_auth
            # Combine cookies
            if cookies is None:
                cookies = {}
            cookies.update({"BbRouter": bbrouter})
            self.session.cookies.update(cookies)
            self.load_all_recursively = load_all_recursively
            self.check_bs4()

        def check_bs4(self) -> None:
            """Check if BeautifulSoup4 is installed.

            Raises:
                ImportError: If BeautifulSoup4 is not installed.
            """
            try:
                import bs4  # noqa: F401
            except ImportError:
                raise ImportError(
                    "BeautifulSoup4 is required for BlackboardLoader. "
                    "Please install it with `pip install beautifulsoup4`."
                )

        def load(self) -> List[Document]:
            """Load data into document objects.

            Returns:
                List of documents.
            """
            if self.load_all_recursively:
                soup_info = self.scrape()
                self.folder_path = self._get_folder_path(soup_info)
                relative_paths = self._get_paths(soup_info)
                documents = []
                for path in relative_paths:
                    url = self.base_url + path
                    print(f"Fetching documents from {url}")
                    soup_info = self._scrape(url)
                    with contextlib.suppress(ValueError):
                        documents.extend(self._get_documents(soup_info))
                return documents
            else:
                print(f"Fetching documents from {self.web_path}")
                soup_info = self.scrape()
                self.folder_path = self._get_folder_path(soup_info)
                return self._get_documents(soup_info)

        def _get_folder_path(self, soup: Any) -> str:
            """Get the folder path to save the documents in.

            Args:
                soup: BeautifulSoup4 soup object.

            Returns:
                Folder path.
            """
            # Get the course name
            course_name = soup.find("span", {"id": "crumb_1"})
            if course_name is None:
                raise ValueError("No course name found.")
            course_name = course_name.text.strip()
            # Prepare the folder path
            course_name_clean = (
                unquote(course_name)
                .replace(" ", "_")
                .replace("/", "_")
                .replace(":", "_")
                .replace(",", "_")
                .replace("?", "_")
                .replace("'", "_")
                .replace("!", "_")
                .replace('"', "_")
            )
            # Get the folder path
            folder_path = Path(".") / course_name_clean
            return str(folder_path)

        def _get_documents(self, soup: Any) -> List[Document]:
            """Fetch content from page and return Documents.

            Args:
                soup: BeautifulSoup4 soup object.

            Returns:
                List of documents.
            """
            attachments = self._get_attachments(soup)
            self._download_attachments(attachments)
            documents = self._load_documents()
            return documents

        def _get_attachments(self, soup: Any) -> List[str]:
            """Get all attachments from a page.

            Args:
                soup: BeautifulSoup4 soup object.

            Returns:
                List of attachments.
            """
            from bs4 import BeautifulSoup, Tag

            # Get content list
            content_list = soup.find("ul", {"class": "contentList"})
            if content_list is None:
                raise ValueError("No content list found.")
            content_list: BeautifulSoup  # type: ignore
            # Get all attachments
            attachments = []
            for attachment in content_list.find_all("ul", {"class": "attachments"}):
                attachment: Tag  # type: ignore
                for link in attachment.find_all("a"):
                    link: Tag  # type: ignore
                    href = link.get("href")
                    # Only add if href is not None and does not start with #
                    if href is not None and not href.startswith("#"):
                        attachments.append(href)
            return attachments

        def _download_attachments(self, attachments: List[str]) -> None:
            """Download all attachments.

            Args:
                attachments: List of attachments.
            """
            # Make sure the folder exists
            Path(self.folder_path).mkdir(parents=True, exist_ok=True)
            # Download all attachments
            for attachment in attachments:
                self.download(attachment)

        def _load_documents(self) -> List[Document]:
            """Load all documents in the folder.

            Returns:
                List of documents.
            """
            # Create the document loader
            loader = DirectoryLoader(
                path=self.folder_path, glob="*.pdf", loader_cls=PyPDFLoader  # type: ignore
            )
            # Load the documents
            documents = loader.load()
            # Return all documents
            return documents

        def _get_paths(self, soup: Any) -> List[str]:
            """Get all relative paths in the navbar."""
            relative_paths = []
            course_menu = soup.find("ul", {"class": "courseMenu"})
            if course_menu is None:
                raise ValueError("No course menu found.")
            for link in course_menu.find_all("a"):
                href = link.get("href")
                if href is not None and href.startswith("/"):
                    relative_paths.append(href)
            return relative_paths

        def download(self, path: str) -> None:
            """Download a file from a url.

            Args:
                path: Path to the file.
            """
            # Get the file content
            response = self.session.get(self.base_url + path, allow_redirects=True)
            # Get the filename
            filename = self.parse_filename(response.url)
            # Write the file to disk
            with open(Path(self.folder_path) / filename, "wb") as f:
                f.write(response.content)

        def parse_filename(self, url: str) -> str:
            """Parse the filename from a url.

            Args:
                url: Url to parse the filename from.

            Returns:
                The filename.
            """
            if (url_path := Path(url)) and url_path.suffix == ".pdf":
                return url_path.name
            else:
                return self._parse_filename_from_url(url)

        def _parse_filename_from_url(self, url: str) -> str:
            """Parse the filename from a url.

            Args:
                url: Url to parse the filename from.

            Returns:
                The filename.

            Raises:
                ValueError: If the filename could not be parsed.
            """
            filename_matches = re.search(r"filename%2A%3DUTF-8%27%27(.+)", url)
            if filename_matches:
                filename = filename_matches.group(1)
            else:
                raise ValueError(f"Could not parse filename from {url}")
            if ".pdf" not in filename:
                raise ValueError(f"Incorrect file type: {filename}")
            filename = filename.split(".pdf")[0] + ".pdf"
            filename = unquote(filename)
            filename = filename.replace("%20", " ")
            return filename

    if __name__ == "__main__":
        loader = BlackboardLoader(
            "https://<YOUR BLACKBOARD URL"
            " HERE>/webapps/blackboard/content/listContent.jsp?course_id=_<YOUR COURSE ID"
            " HERE>_1&content_id=_<YOUR CONTENT ID HERE>_1&mode=reset",
            "<YOUR BBROUTER COOKIE HERE>",
            load_all_recursively=True,
        )
        documents = loader.load()
        print(f"Loaded {len(documents)} pages of PDFs from {loader.web_path}")