import re
from typing import Optional
from bs4 import BeautifulSoup
from pydantic import BaseModel

from scrap.base import ScrapperBackendBase


class PatentScrapResult(BaseModel):
    """Schema for the result of scraping a google patents page."""
    # The title of the patent.
    title: str
    # The abstract of the patent, if available.
    abstract: Optional[str] = None
    # The full description of the patent containing the field of the invention, background, summary, etc.
    description: Optional[str] = None
    # The full claims of the patent.
    claims: Optional[str] = None
    # The field of the invention, if available.
    field_of_invention: Optional[str] = None
    # The background of the invention, if available.
    background: Optional[str] = None


class GpatentsScrapBackend(ScrapperBackendBase):
    @property
    def content_type(self):
        return "patent"

    async def scrap(self, client, id):
        headers = {
            "User-Agent": "Mozilla/5.0 (compatible; GPTBot/1.0; +https://openai.com/gptbot)"
        }
        patent_url = f"https://patents.google.com/patent/{id}/en"
        response = await client.get(patent_url, headers=headers)
        response.raise_for_status()

        soup = BeautifulSoup(response.text, "html.parser")

        # Abstract
        abstract_div = soup.find("div", {"class": "abstract"})
        abstract = abstract_div.get_text(
            strip=True) if abstract_div else None

        # Description
        description_section = soup.find("section", itemprop="description")
        description = description_section.get_text(
            separator="\n", strip=True) if description_section else None

        # Field of the Invention
        invention_field_match = re.findall(
            r"(FIELD OF THE INVENTION|TECHNICAL FIELD)(.*?)(?:(BACKGROUND|BACKGROUND OF THE INVENTION|SUMMARY|BRIEF SUMMARY|DETAILED DESCRIPTION|DESCRIPTION OF THE RELATED ART))", description, re.IGNORECASE | re.DOTALL) if description_section else None
        invention_field = invention_field_match[0][1].strip(
        ) if invention_field_match else None

        # Background of the Invention
        invention_background_match = re.findall(
            r"(BACKGROUND OF THE INVENTION|BACKGROUND)(.*?)(?:(SUMMARY|BRIEF SUMMARY|DETAILED DESCRIPTION|DESCRIPTION OF THE PREFERRED EMBODIMENTS|DESCRIPTION))", description, re.IGNORECASE | re.DOTALL) if description_section else None
        invention_background = invention_background_match[0][1].strip(
        ) if invention_background_match else None

        # Claims
        claims_section = soup.find("section", itemprop="claims")
        claims = claims_section.get_text(
            separator="\n", strip=True) if claims_section else None

        # Patent Title
        meta_title = soup.find("meta", {"name": "DC.title"}).get(
            "content").strip()

        return PatentScrapResult(
            abstract=abstract,
            description=description,
            claims=claims,
            title=meta_title,
            field_of_invention=invention_field,
            background=invention_background
        )

    @property
    def content_type(self):
        return "patent"