#!/usr/bin/env bash
set -euo pipefail

cd "$(dirname "$0")"

# LinuxCNC source basis: Puma560 DH parameter output is generated from
# configs/sim/axis/vismach/puma/puma560_dh.hal setp genserkins.{A,ALPHA,D}-N
# values used by LinuxCNC genser/switchkins simulation configs.
linuxcnc_root=${LINUXCNC_ROOT:-../linuxcnc}

usage() {
    echo "usage: $0 [linuxcnc-root-relative-puma560-dh-hal]" >&2
}

case "${1:-}" in
    --help|-h)
        usage
        exit 0
        ;;
    --*)
        usage
        echo "unknown LinuxCNC puma560 DH generator option: $1" >&2
        exit 1
        ;;
esac
if [[ -n "${2:-}" ]]; then
    usage
    echo "too many LinuxCNC puma560 DH generator arguments" >&2
    exit 1
fi

source_path=${1:-configs/sim/axis/vismach/puma/puma560_dh.hal}
if [[ "$source_path" = /* || "$source_path" == .. || "$source_path" == ../* || "$source_path" == */.. || "$source_path" == */../* ]]; then
    echo "LinuxCNC puma560 DH HAL source path must stay LinuxCNC-root relative: $source_path" >&2
    exit 1
fi
if [[ "$source_path" != *.hal ]]; then
    echo "LinuxCNC puma560 DH source must be a HAL file: $source_path" >&2
    exit 1
fi

source_file="$linuxcnc_root/$source_path"

if [[ ! -f "$source_file" ]]; then
    echo "missing LinuxCNC puma560 DH HAL source: $source_file" >&2
    exit 1
fi

awk -v source_path="$source_path" '
function fail(message) {
    print message > "/dev/stderr"
    exit 1
}

$1 == "setp" && $2 ~ /^genserkins\.(A|ALPHA|D)-[0-5]$/ {
    split($2, qualified, ".")
    split(qualified[2], name_index, "-")
    name = name_index[1]
    joint_index = name_index[2] + 0
    values[name, joint_index] = $3
}

END {
    names[0] = "A"
    arrays["A"] = "a"
    names[1] = "ALPHA"
    arrays["ALPHA"] = "alpha"
    names[2] = "D"
    arrays["D"] = "d"

    print "// Generated by ./generate-linuxcnc-puma560-dh-parameters.sh."
    print "// Source: linuxcnc/" source_path " setp genserkins.{A,ALPHA,D}-N values."

    for (n = 0; n < 3; n++) {
        name = names[n]
        array = arrays[name]
        for (i = 0; i < 6; i++) {
            key = name SUBSEP i
            if (!(key in values)) {
                fail("missing " name "-" i " in " source_path)
            }
            print "    parameters." array "[" i "] = " values[key] ";"
        }
        if (n < 2) {
            print ""
        }
    }
}
' "$source_file"