import pymupdf ## fitz  # PyMuPDF
from langchain.text_splitter import RecursiveCharacterTextSplitter

def extract_text_from_pdf(pdf_file):
    ##  doc = pymupdf.open(pdf_file)
    # with pymupdf.open(pdf_file) as doc:
    # with fitz.open(pdf_file) as doc:
    text = ""
    with pymupdf.open(stream=pdf_file.read(), filetype="pdf") as doc:
        for page in doc:
            text += page.get_text()
    return text

MARKDOWN_SEPARATORS = [
    "\n#{1,6} ",
    "```\n",
    "\n\\*\\*\\*+\n",
    "\n---+\n",
    "\n___+\n",
    "\n\n",
    "\n",
    " ",
    "",
]

def chunk_text(text, chunk_size=1000, chunk_overlap=100):
    text_splitter = RecursiveCharacterTextSplitter(
        chunk_size=chunk_size,
        chunk_overlap=chunk_overlap,
        add_start_index=True,
        strip_whitespace=True,
        separators=MARKDOWN_SEPARATORS
    )
    return text_splitter.split_text(text)