from pathlib import Path
from typing import Union, List, Iterator

from phi.document import Document
from phi.document.reader.text import TextReader
from phi.knowledge.base import AssistantKnowledge


class TextKnowledgeBase(AssistantKnowledge):
    path: Union[str, Path]
    formats: List[str] = [".txt"]
    reader: TextReader = TextReader()

    @property
    def document_lists(self) -> Iterator[List[Document]]:
        """Iterate over text files and yield lists of documents.
        Each object yielded by the iterator is a list of documents.

        Returns:
            Iterator[List[Document]]: Iterator yielding list of documents
        """

        _file_path: Path = Path(self.path) if isinstance(self.path, str) else self.path

        if _file_path.exists() and _file_path.is_dir():
            for _file in _file_path.glob("**/*"):
                if _file.suffix in self.formats:
                    yield self.reader.read(path=_file)
        elif _file_path.exists() and _file_path.is_file() and _file_path.suffix in self.formats:
            yield self.reader.read(path=_file_path)