"""Shared utilities for the memory module — NATS access, path helpers, JSON loading."""

import json
import logging
import os
from datetime import datetime, timezone
from pathlib import Path


def get_workspace_dir() -> Path:
    """Get workspace directory from WORKSPACE_DIR env or cwd."""
    return Path(os.environ.get("WORKSPACE_DIR", os.getcwd()))


def get_agent_name() -> str:
    """Get agent name from AGENT_NAME env or 'agent'."""
    return os.environ.get("AGENT_NAME", "agent")


def get_reboot_dir(workspace: Path = None) -> Path:
    """Get memory/reboot directory, creating if needed."""
    ws = workspace or get_workspace_dir()
    d = ws / "memory" / "reboot"
    d.mkdir(parents=True, exist_ok=True)
    return d


def get_nats_credentials(workspace: Path = None) -> dict:
    """Load NATS credentials from env vars or config file.

    Priority: env vars > config file at WORKSPACE_DIR/config/nats/credentials.env
    Returns dict with keys: url, user, password
    """
    url = os.environ.get("NATS_URL", "")
    user = os.environ.get("NATS_USER", "")
    password = os.environ.get("NATS_PASSWORD", "")

    if not (url and user and password):
        ws = workspace or get_workspace_dir()
        creds_file = ws / "config" / "nats" / "credentials.env"
        if creds_file.exists():
            for line in creds_file.read_text().strip().split("\n"):
                if "=" in line and not line.startswith("#"):
                    k, v = line.split("=", 1)
                    k, v = k.strip(), v.strip().strip('"')
                    if k == "NATS_URL" and not url:
                        url = v
                    elif k in ("NATS_USER",) and not user:
                        user = v
                    elif k in ("NATS_PASSWORD", "NATS_CLAUDIA_PW") and not password:
                        password = v

    return {
        "url": url or "nats://localhost:4222",
        "user": user,
        "password": password,
    }


def get_nats_env(workspace: Path = None) -> dict:
    """Return os.environ copy with NATS credentials set for nats CLI."""
    creds = get_nats_credentials(workspace)
    env = os.environ.copy()
    if creds["user"]:
        env["NATS_USER"] = creds["user"]
    if creds["password"]:
        env["NATS_PASSWORD"] = creds["password"]
    if creds["url"]:
        env["NATS_URL"] = creds["url"]
    return env


def load_json(path: Path) -> dict:
    """Load JSON file, returning empty dict on failure."""
    try:
        return json.loads(path.read_text())
    except (FileNotFoundError, json.JSONDecodeError):
        return {}


def save_json(path: Path, data: dict):
    """Atomically write JSON to file."""
    path.parent.mkdir(parents=True, exist_ok=True)
    tmp = path.with_suffix(".tmp")
    tmp.write_text(json.dumps(data, indent=2, ensure_ascii=False))
    tmp.rename(path)


def load_facts(path: Path) -> list[dict]:
    """Load facts from a JSONL file."""
    if not path.exists():
        return []
    facts = []
    for line in path.read_text().strip().split("\n"):
        if not line.strip():
            continue
        try:
            fact = json.loads(line)
            if "text" not in fact and "fact" in fact:
                fact["text"] = fact["fact"]
            facts.append(fact)
        except json.JSONDecodeError:
            continue
    return facts


def setup_logging(name: str, workspace: Path = None) -> logging.Logger:
    """Configure logging to workspace/logs/ and stderr."""
    ws = workspace or get_workspace_dir()
    log_dir = ws / "logs"
    log_dir.mkdir(parents=True, exist_ok=True)
    log_file = log_dir / f"{name}.log"

    logging.basicConfig(
        level=logging.INFO,
        format="%(asctime)s [%(levelname)s] %(message)s",
        handlers=[
            logging.FileHandler(log_file),
            logging.StreamHandler(),
        ],
    )
    return logging.getLogger(name)