filter.py

from datetime import datetime
from typing import List, Optional

from regex import regex


class Filter(object):
    @classmethod
    def from_dicts(cls, filters: Optional[List[dict]]):
        if not filters:
            return []
        return [cls.from_dict(**d) for d in filters if d]

    @classmethod
    def from_dict(cls, **kwargs):
        if len(kwargs.items()) == 0:
            raise ValueError("No arguments provided")

        if title := kwargs.get("title"):
            return TitleFilter(
                pattern=title,
                case_sensitive=kwargs.get("case_sensitive", False),
                invert=kwargs.get("invert", False),
            )
        if in_seconds := kwargs.get("in_seconds"):
            return TimeFilter(in_seconds=in_seconds)

        raise ValueError(f"Unknown filter: {kwargs}")

    def predicate_item(self, item):
        raise NotImplementedError

    def filter_items(self, items):
        return [item for item in items if self.predicate_item(item)]


class TitleFilter(Filter):
    def __init__(self, pattern: str, case_sensitive=False, invert=False):
        self.pattern = regex.compile(pattern if case_sensitive else pattern.lower())
        self.invert = invert
        self.case_sensitive = case_sensitive

    def predicate_item(self, item):
        title = item["title"] if self.case_sensitive else item["title"].lower()
        contains = self.pattern.search(title) is not None
        return contains ^ self.invert


class TimeFilter(Filter):
    def __init__(self, in_seconds: int):
        self.in_seconds = in_seconds

    def predicate_item(self, item):
        if "pubdate" not in item:
            return False

        return (
            datetime.timestamp(datetime.now()) - datetime.timestamp(item["pubdate"])
            < self.in_seconds
        )