"""Generate a keymap.c from a configurator export.
"""
import json

from argcomplete.completers import FilesCompleter
from milc import cli

import qmk.keymap
import qmk.path


@cli.argument('-o', '--output', arg_only=True, type=qmk.path.normpath, help='File to write to')
@cli.argument('-q', '--quiet', arg_only=True, action='store_true', help="Quiet mode, only output error messages")
@cli.argument('filename', type=qmk.path.FileType('r'), arg_only=True, completer=FilesCompleter('.json'), help='Configurator JSON file')
@cli.subcommand('Creates a keymap.c from a QMK Configurator export.')
def json2c(cli):
    """Generate a keymap.c from a configurator export.

    This command uses the `qmk.keymap` module to generate a keymap.c from a configurator export. The generated keymap is written to stdout, or to a file if -o is provided.
    """

    try:
        # Parse the configurator from json file (or stdin)
        user_keymap = json.load(cli.args.filename)

    except json.decoder.JSONDecodeError as ex:
        cli.log.error('The JSON input does not appear to be valid.')
        cli.log.error(ex)
        return False

    # Environment processing
    if cli.args.output and cli.args.output.name == '-':
        cli.args.output = None

    # Generate the keymap
    keymap_c = qmk.keymap.generate_c(user_keymap)

    if cli.args.output:
        cli.args.output.parent.mkdir(parents=True, exist_ok=True)
        if cli.args.output.exists():
            cli.args.output.replace(cli.args.output.parent / (cli.args.output.name + '.bak'))
        cli.args.output.write_text(keymap_c)

        if not cli.args.quiet:
            cli.log.info('Wrote keymap to %s.', cli.args.output)

    else:
        print(keymap_c)