# Copyright 2021-2024 VyOS maintainers and contributors <maintainers@vyos.io>
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# T3417: migrate BGP tagNode to node as we can only have one BGP process

from vyos.configtree import ConfigTree

def migrate(config: ConfigTree) -> None:
    base = ['protocols', 'bgp']

    if not config.exists(base) or not config.is_tag(base):
        # Nothing to do
        return

    # Only one BGP process is supported, thus this operation is savea
    asn = config.list_nodes(base)
    bgp_base = base + asn

    # We need a temporary copy of the config
    tmp_base = ['protocols', 'bgp2']
    config.copy(bgp_base, tmp_base)

    # Now it's save to delete the old configuration
    config.delete(base)

    # Rename temporary copy to new final config and set new "local-as" option
    config.rename(tmp_base, 'bgp')
    config.set(base + ['local-as'], value=asn[0])