"""FileStorage — persist addressbook in hosts.txt format."""

from __future__ import annotations

import os

from i2p_apps.addressbook.book import AddressbookEntry


class FileStorage:
    """Persist addressbook in hosts.txt format (hostname=destination per line)."""

    def __init__(self, path: str) -> None:
        self._path = path

    def save(self, entries: dict[str, AddressbookEntry]) -> None:
        """Write entries to file in hosts.txt format."""
        with open(self._path, "w") as f:
            for _key, entry in sorted(entries.items()):
                f.write(f"{entry.hostname}={entry.destination}\n")

    def load(self) -> dict[str, AddressbookEntry]:
        """Load entries from hosts.txt file. Missing file returns empty dict."""
        if not os.path.exists(self._path):
            return {}

        entries: dict[str, AddressbookEntry] = {}
        with open(self._path, "r") as f:
            for line in f:
                line = line.strip()
                if not line or line.startswith("#"):
                    continue
                if "=" not in line:
                    continue
                hostname, destination = line.split("=", 1)
                hostname = hostname.strip().lower()
                destination = destination.strip()
                entries[hostname] = AddressbookEntry(
                    hostname=hostname,
                    destination=destination,
                    source="local",
                )
        return entries

    @property
    def path(self) -> str:
        """Return the file path."""
        return self._path