#!/usr/bin/env bash

set -euo pipefail

print_err() {
    printf "%s\n" "$1" >&2
}

usage() {
    print_err "Usage: , <program> [argument]..."
}

find_program() {
    local CANDIDATE
    CANDIDATE="$(nix-locate --top-level --minimal --at-root --whole-name "/bin/$1")"
    if [ "$(printf '%s\n' "$CANDIDATE" | wc -l)" -gt 1 ]; then
        CANDIDATE="$(printf '%s' "$CANDIDATE" | fzf-tmux)"
    fi
    printf '%s' "$CANDIDATE"
}

if [ $# -lt 1 ]; then
    usage
    exit 1
fi

PROGRAM="$(find_program "$1")"
if [ -z "$PROGRAM" ]; then
    print_err "No match found for $1"
    exit 1
fi

nix shell "${COMMA_NIXPKGS_FLAKE:-nixpkgs}#$PROGRAM" -c "$@"