#!/usr/bin/env nix-shell
#!nix-shell -p jq -i bash

# Usage: niv2flake.sh [sources.json file

set -euo pipefail

if [[ ! -z ${1:-} ]]; then
    NIV="$1"
    shift
else
    if [[ -t 0 ]]; then
        NIV=nix/sources.json

    else
        NIV=/proc/self/fd/0
    fi
fi

jq '.[] |= if .type == "git"
then { type: "git", url: .url }
else if .type == "file"
then { type: "file", url: .url }
else if .type == "tarball" then
if .owner != null
then { url: ("github:" + .owner + "/" + .repo + "/" + .branch) }
else { type: "file", url: .url } end
else . end end end' "$NIV" | nix eval --impure --expr "(builtins.fromJSON (builtins.readFile /proc/self/fd/0))" | nixfmt