"""Persistence for remembered remote browser endpoints and key specs."""
from __future__ import annotations

import json
import os
from pathlib import Path

from browser_cli.constants import CONFIG_DIR
from browser_cli.endpoints import _normalize_endpoint

REMOTE_REGISTRY_PATH = CONFIG_DIR / "remotes.json"

def load_remotes() -> dict[str, dict[str, str]]:
  if not REMOTE_REGISTRY_PATH.exists():
    return {}
  try:
    data = json.loads(REMOTE_REGISTRY_PATH.read_text(encoding="utf-8"))
  except Exception:
    return {}
  if not isinstance(data, dict):
    return {}
  # Normalize keys so old entries stored as "domain:443" match current lookups.
  return {_normalize_endpoint(str(endpoint)): cfg for endpoint, cfg in data.items() if isinstance(cfg, dict)}

def is_valid_key_spec(value: str) -> bool:
  """Return True for 'agent', 'agent:<selector>', or a plausible key file path."""
  return value == "agent" or value.startswith("agent:") or (
    not value.startswith("<") and ("/" in value or Path(value).suffix in {".pem", ".key"})
  )

def save_remote_key(endpoint: str, key_spec: str) -> None:
  """Persist the key spec (e.g. 'agent' or a file path) for a remote endpoint."""
  if not endpoint or not key_spec or not is_valid_key_spec(key_spec):
    return
  remotes = load_remotes()
  current = remotes.get(endpoint, {})
  current["key"] = key_spec
  remotes[endpoint] = current
  REMOTE_REGISTRY_PATH.parent.mkdir(parents=True, exist_ok=True)
  fd = os.open(str(REMOTE_REGISTRY_PATH), os.O_WRONLY | os.O_CREAT | os.O_TRUNC, 0o600)
  with os.fdopen(fd, "w", encoding="utf-8") as f:
    f.write(json.dumps(remotes, indent=2, sort_keys=True))

def key_for_remote(endpoint: str | None) -> str | None:
  if not endpoint:
    return None
  cfg = load_remotes().get(endpoint) or {}
  key = cfg.get("key")
  if not key:
    return None
  key_str = str(key)
  # Reject corrupted values (e.g. str(AgentKey(...)) saved by an older bug).
  return key_str if is_valid_key_spec(key_str) else None