from contextlib import contextmanager
from pathlib import Path

import attr
import json

# Used to avoid duplicates in the log
from pybloom_live import BloomFilter

def make_filter():
    return BloomFilter(
            capacity=settings["MAX_POSTS"],
            error_rate=0.001
        )

@attr.s
class Archive:
    archive_type = attr.ib()

    # We give the Archive class a file handle
    # This is better because the archive function
    # should not know about anything related to filesystem paths
    archive_file = attr.ib()

    _bloom_filter = attr.ib(factory=make_filter)

    def archive(self, content):
        """
        Archive an object
        """
        print("Archiving {0}".format(content))

        if content.name not in self._bloom_filter:
            self.archive_file.write(json.dumps(attr.asdict(content)))
            self._bloom_filter.add(content.name)
        return 

@contextmanager
def archiver(archive_type):
    archive_file = open("./%s.log" % archive_type, mode="ta", buffering=1)

    archiver_instance = Archive(
            archive_type=archive_type,
            archive_file=archive_file
    )

    try:
        yield archiver_instance
    finally:
        archive_file.close()