#!/usr/bin/env python3
from backup import FileBackend
import os
import click
import json


@click.command()
@click.argument("lightning-dir", type=click.Path(exists=True))
@click.argument("backup-dir", type=click.Path(exists=True))
def init(lightning_dir, backup_dir):
    destination = 'file://' + os.path.join(backup_dir, 'backup.dbak')
    backend = FileBackend(destination)
    backend.version, backend.prev_version = 0, 0
    backend.offsets = [512, 0]
    backend.version_count = 0
    backend.write_metadata()

    lock_file = os.path.join(lightning_dir, "backup.lock")

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

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


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


cli.add_command(init)

if __name__ == "__main__":
    cli()