"""Addressbook manager for SusiDNS.

Manages hostname-to-destination mappings with search, file I/O,
and integration with the addressbook storage.

Ported from i2p.susi.dns.AddressbookBean.
"""

from __future__ import annotations

from dataclasses import dataclass
from pathlib import Path


@dataclass
class AddressbookEntry:
    """A single hostname→destination mapping."""
    hostname: str
    destination: str

    def __str__(self) -> str:
        return f"{self.hostname}={self.destination}"


class AddressbookManager:
    """Manages .i2p hostname-to-destination mappings."""

    def __init__(self) -> None:
        self._entries: dict[str, str] = {}

    def add(self, hostname: str, destination: str) -> None:
        """Add or update an entry."""
        self._entries[hostname] = destination

    def remove(self, hostname: str) -> None:
        """Remove an entry."""
        self._entries.pop(hostname, None)

    def lookup(self, hostname: str) -> str | None:
        """Look up a destination by hostname."""
        return self._entries.get(hostname)

    def list_entries(self) -> list[AddressbookEntry]:
        """List all entries sorted by hostname."""
        return [
            AddressbookEntry(h, d)
            for h, d in sorted(self._entries.items())
        ]

    def search(self, query: str) -> list[AddressbookEntry]:
        """Search entries by hostname prefix."""
        query_lower = query.lower()
        return [
            AddressbookEntry(h, d)
            for h, d in sorted(self._entries.items())
            if query_lower in h.lower()
        ]

    def save(self, path: Path) -> None:
        """Save entries to a hosts.txt file."""
        lines = [f"{h}={d}" for h, d in sorted(self._entries.items())]
        path.write_text("\n".join(lines) + "\n")

    @classmethod
    def from_file(cls, path: Path) -> AddressbookManager:
        """Load entries from a hosts.txt file."""
        mgr = cls()
        if not path.exists():
            return mgr
        for line in path.read_text().splitlines():
            line = line.strip()
            if not line or line.startswith("#"):
                continue
            if "=" in line:
                hostname, destination = line.split("=", 1)
                mgr.add(hostname.strip(), destination.strip())
        return mgr