#!/usr/bin/env python3
from backends import get_backend
from backend import Change
from server import SocketServer, setup_server_logging

import os
import click
import json
import logging
import sqlite3
import sys

root = logging.getLogger()
root.setLevel(logging.INFO)

handler = logging.StreamHandler(sys.stdout)
handler.setLevel(logging.DEBUG)
formatter = logging.Formatter('%(message)s')
handler.setFormatter(formatter)
root.addHandler(handler)

@click.command()
@click.argument("backend-url")
@click.option('--lightning-dir', type=click.Path(exists=True), default=None, help='Use an existing lightning directory (default: initialize an empty backup).')
def init(lightning_dir, backend_url):
    destination = backend_url
    backend = get_backend(destination, create=True)

    if lightning_dir is not None:
        lock_file = os.path.join(lightning_dir, "backup.lock")
        db_file = os.path.join(lightning_dir, "lightningd.sqlite3")

        with open(lock_file, "w") as f:
            f.write(json.dumps({
                'backend_url': destination,
            }))

        data_version = 0
        if os.path.exists(db_file):
            print("Found an existing database at {db_file}, initializing the backup with a snapshot".format(db_file=db_file))
            # Peek into the DB to see if we have
            db = sqlite3.connect(db_file)
            cur = db.cursor()
            rows = cur.execute("SELECT intval FROM vars WHERE name = 'data_version'")
            data_version = rows.fetchone()[0]

            snapshot = Change(
                version=data_version,
                snapshot=open(db_file, 'rb').read(),
                transaction=None
            )
            if not backend.add_change(snapshot):
                print("Could not write snapshot to backend")
                sys.exit(1)
            else:
                print("Successfully written initial snapshot to {destination}".format(destination=destination))
        else:
            print("Database does not exist yet, created an empty backup file")

    print("Initialized backup backend {destination}, you can now start Core-Lightning".format(
        destination=destination,
    ))


@click.command()
@click.argument("backend-url")
@click.argument("restore-destination")
def restore(backend_url, restore_destination):
    destination = backend_url
    backend = get_backend(destination)
    backend.restore(restore_destination)


@click.command()
@click.argument("backend-url")
@click.argument("addr")
@click.option('--log-mode', type=click.Choice(['plain', 'systemd'], case_sensitive=False), default='plain', help='Debug log mode, defaults to plain')
@click.option('--log-level', type=click.Choice(['debug', 'info', 'notice', 'warning', 'error', 'critical'], case_sensitive=False), default='info', help='Debug log level, defaults to info')
def server(backend_url, addr, log_mode, log_level):
    backend = get_backend(backend_url)
    addr, port = addr.split(':')
    port = int(port)

    setup_server_logging(log_mode, log_level)

    server = SocketServer((addr, port), backend)
    server.run()


@click.group()
def cli():
    pass


cli.add_command(init)
cli.add_command(restore)
cli.add_command(server)

if __name__ == "__main__":
    cli()