#!/usr/bin/env python3
"""
CarConnectivity vehicle data collector.

Periodically fetches selected domains from a VW vehicle via CarConnectivity
and appends timestamped records to a JSON file.  The JSON structure mirrors
the domain hierarchy: domain → status-object → field.

Usage examples
--------------
# Credentials file with all settings:
  python -m server.main -c credentials/alex.json

# Override username/password via env vars:
  export WC_USER=me@example.com WC_PASS=secret
  python -m server.main -c credentials/alex.json

# Override domains on the CLI:
  python -m server.main -c credentials/alex.json -d charging,measurements

Available domains: charging, climatisation, electric_drive, connectivity, vehicle, position, doors

Credentials file format (JSON)
-------------------------------
{
  "credentials": {
    "username": "me@example.com",
    "password": "secret"
  },
  "vin":        "WVWZZZE1ZMP123456",
  "domains":    ["charging", "measurements", "readiness"],
  "interval_s": 300,
  "host":       "0.0.0.0",
  "port":       9999,
  "log_dir":    "./logs"
}

Push server
-----------
The collector listens on host/port from the credentials file (default 0.0.0.0:9999).
Each connected TCP client receives every new snapshot as a single
line of JSON (newline-delimited) the moment it is collected.
Connect with:  nc localhost 9999  or any TCP client that reads lines.
"""

import argparse
import json
import os
import sys
from pathlib import Path

from .collect import run
from .data_model import ALL_DOMAINS


def main() -> None:
    p = argparse.ArgumentParser(
        description=__doc__,
        formatter_class=argparse.RawDescriptionHelpFormatter,
    )

    creds = p.add_argument_group(
        "credentials (also accepted via WC_USER / WC_PASS env vars or -c FILE)"
    )
    creds.add_argument(
        "-c", "--credentials",
        metavar="FILE",
        help="JSON file with connection settings (see format above).",
    )
    creds.add_argument(
        "-u", "--username",
        default=os.environ.get("WC_USER"),
        help="MyVolkswagen email (overrides credentials file)",
    )
    creds.add_argument(
        "-p", "--password",
        default=os.environ.get("WC_PASS"),
        help="MyVolkswagen password (overrides credentials file)",
    )

    p.add_argument(
        "-d", "--domains",
        default=None,
        metavar="DOMAIN[,DOMAIN…]",
        help=(
            "Comma-separated domains to collect, or 'all' (overrides credentials file).  "
            f"Available: {', '.join(ALL_DOMAINS)}.  "
            "Default: charging,electric_drive,connectivity"
        ),
    )
    p.add_argument(
        "--max-records",
        type=int,
        default=None,
        metavar="N",
        help="Keep only the last N records per file (default: unlimited)",
    )
    p.add_argument(
        "-i", "--interval",
        type=int,
        default=None,
        metavar="SECONDS",
        help="Collection interval in seconds (overrides credentials file, default: 300)",
    )
    p.add_argument(
        "--host",
        default=None,
        help="Push server bind address (overrides credentials file, default: 0.0.0.0)",
    )
    p.add_argument(
        "--port",
        type=int,
        default=None,
        help="Push server TCP port (overrides credentials file, default: 9999)",
    )
    p.add_argument(
        "--log-dir",
        default=None,
        metavar="DIR",
        help="Directory for rotating log files (overrides credentials file, default: ./logs)",
    )
    p.add_argument("-v", "--verbose", action="store_true", help="Enable debug logging")
    p.add_argument(
        "--diff",
        action="store_true",
        default=None,
        help="Send diffs instead of full snapshots over the push server (overrides credentials file, default: off)",
    )
    p.add_argument(
        "--dry",
        action="store_true",
        help="Skip CarConnectivity login and data collection; run push server only (for GUI testing)",
    )
    p.add_argument(
        "--list-domains",
        action="store_true",
        help="Print available domains and exit",
    )

    args = p.parse_args()

    if args.list_domains:
        print("\n".join(ALL_DOMAINS))
        sys.exit(0)

    creds_data: dict = {}
    if args.credentials:
        creds_path = Path(args.credentials)
        if not creds_path.exists():
            p.error(f"Credentials file not found: {args.credentials}")
        try:
            creds_data = json.loads(creds_path.read_text())
        except json.JSONDecodeError as exc:
            p.error(f"Invalid JSON in credentials file: {exc}")

    nested = creds_data.get("credentials", {})
    if args.username is None:
        args.username = nested.get("username") or creds_data.get("username")
    if args.password is None:
        args.password = nested.get("password") or creds_data.get("password")

    args.vin = creds_data.get("vin")

    if args.domains is None:
        raw_domains = creds_data.get("domains")
        if isinstance(raw_domains, list):
            args.domains = ",".join(raw_domains)
        else:
            args.domains = raw_domains or "charging,electric_drive,connectivity"

    if args.interval is None:
        args.interval = int(creds_data.get("interval_s", 300))
    if args.host is None:
        args.host = creds_data.get("host", "0.0.0.0")
    if args.port is None:
        args.port = int(creds_data.get("port", 9999))
    if args.log_dir is None:
        args.log_dir = creds_data.get("log_dir", "./logs")
    if args.diff is None:
        args.diff = bool(creds_data.get("diff", False))

    if not args.dry and (not args.username or not args.password):
        p.error(
            "Username and password are required.  "
            "Provide them in the credentials file or via -u/-p / WC_USER / WC_PASS."
        )

    run(args)


if __name__ == "__main__":
    main()