# Usage: 
# ^nft --json list sets | nu --stdin api/netbird-nft-sets.nu
# open --raw test-data/nft-sets.json | nu --stdin api/netbird-nft-sets.nu

use netbird-api.nu

def mangle-name [prefix: string, name: string] {
    $prefix + ($name 
        | str replace -ar '\s+' '_'
        | str replace -ar  '\W' '')
}

def find-changed-sets [] {
    let sets = $in # nft_sets
        | rename --column { name: nft_name }
    let peers = netbird-api peers list 
        | insert nft_name { mangle-name 'nbp_' $in.name | str downcase }
        | insert new_elem { [$in.ip] }
    let groups = netbird-api groups list 
        | where peers != null 
        | each { update peers { select id | join $peers id } }
        | insert nft_name { mangle-name 'nbg_' $in.name } # allow uppercase
        | insert new_elem { $in.peers.ip }

    let set_changes = [$peers, $groups] | flatten 
        | join $sets nft_name
        | where { $in.new_elem != $in.elem }
    return $set_changes
}

def generate-nft-commands [] {
# nft add talbe inet <name>     # ignore if table already exists
# nft destroy table inet <name> # ignore if table already removed
    let set_changes = $in
    for $s in $set_changes {
        let path = [$s.family $s.table $s.nft_name] | str join ' '
        print $"flush set ($path)"
        print $"add element ($path) { ($s.new_elem | str join ', ') }"
    }
}

def main [] {
    $in | from json | get nftables | skip 1 | get set 
        | find-changed-sets 
        | generate-nft-commands
}