#!/bin/bash

# This is an example of how nbft can be used in bash to parse the nBFT.
# Borrowed from https://github.com/dracutdevs/dracut/blob/master/modules.d/95nvmf/parse-nvmf-boot-connections.sh

nbft_bin="/usr/bin/nbft2json"

# Set some initial defaults (nvme-cli prefers 'none' for uninitialized parameters)
trtype=none
traddr=none
trsvcid=none
hosttraddr=none

get_namespace() {
    echo $(jq -r .namespace[$1].transport_type,.namespace[$1].subsystem_transport_address,.namespace[$1].subsystem_namespace_nqn,.namespace[$1].subsystem_transport_port,.namespace[$1].hfi_association[] $2)
}

get_discovery() {
    echo $(jq -r .discovery.records[$1].discovery_ctrl_addr $2)
}

parse_nbft() {
    nbft_json=nbft.json

    # Run nbft and save output to $nbft_json. All future queries will be performed on this file.
    if $nbft_bin > $nbft_json 2>/dev/null; then
        # Host ID and Host NQN are per host, so we get them first.
        nbft_hostnqn=$(jq -r .host.initiator_host_nqn $nbft_json)
        nbft_hostid=$(jq -r .host.host_identifier $nbft_json)

	# This is required for nvme-cli to work.
	echo $nbft_hostnqn > /etc/nvme/hostnqn
	echo $nbft_hostid > /etc/nvme/hostid

	# Fetch discovery records from nBFT
        for n in $(seq 0 $(jq '.discovery.number_of_records - 1' $nbft_json 2>/dev/null)); do
	    read trtype traddr trsvcid < <(get_discovery $n $nbft_json | awk -F"/|:|+" '{print $2, $5, $6}')
	    # discovery/connect to all available nqns
	    printf "nvme connect-all -t %s -a %s -s %s\n" $trtype $traddr $trsvcid
        done

	# Fetch trtype, traddr, subnqn, trsvcid and hosttraddr for each namespace
        #for n in $(jq .namespace[].index $nbft_json); do
	for n in $(seq 0 $(jq '.discovery.number_of_namespaces - 1' $nbft_json 2>/dev/null)); do
	    read trtype traddr subnqn trsvcid HFI < <(get_namespace $n $nbft_json)
	    # Get the hosttraddr from the HFI association (typically the NIC/port) for this namespace.

	    HOSTIP=$(jq -r .hfi[$HFI].hfi_info.ip_address $nbft_json)
	    # This check is to ensure that the hosts's IP address from nBFT (uefi dhcp) matches that assigned by Linux.
	    if ip -o addr | grep -q $HOSTIP; then
                hosttraddr="$HOSTIP"
	    fi

	    # connect to each nqn
	    printf "nvme connect -t %s -a %s -s %s -w %s -n %s # nbft_namespace:%s\n" $trtype $traddr $trsvcid $hosttraddr $subnqn $n
        done
    else
        echo "No nBFT detected."
        return 1
    fi
}

parse_nbft