#!/bin/sh

showHelp() {
  echo "update: updates flake inputs"
  echo "usage: update [flags] [input [input ...]]"
  echo ""
  echo "flags:"
  echo "  --help"
  echo "  --dry-run"
  echo "inputs:"
  echo "  all: update every input"
  echo "  safe: update inputs which rarely break the build, or are trivial to patch"
  echo "  unsafe: update inputs which may be annoying to patch if they break the build"
  echo "  nixpkgs"
  echo "  next"
}

inputs=()
dryRun=

parseArgs() {
  for arg in "$@"; do
    case $arg in
      (--help)
        showHelp
        exit 1
        ;;
      (--dry-run)
        dryRun=1
        ;;
      (*)
        addInputs "$arg"
        ;;
    esac
  done
  # if no inputs were specified, assume "all"
  if [ ${#inputs} -eq 0 ]; then
    addInputs all
  fi
}

# add $1 to `inputs` array, after parsing it
addInputs() {
  case $1 in
    (all)
      addInputs safe
      addInputs unsafe
      ;;
    (next)
      addInputs nixpkgs-next-unpatched
      addInputs nixpkgs-staging-unpatched
      ;;
    (safe)
      addInputs next
      addInputs nixpkgs-unpatched
      addInputs sops-nix
      addInputs uninsane-dot-org
      ;;
    (unsafe)
      # these tend to break more frequently
      addInputs mobile-nixos
      addInputs nixpkgs-wayland
      ;;
    (mobile-nixos|nixpkgs-next-unpatched|nixpkgs-staging-unpatched|nixpkgs-unpatched|nixpkgs-wayland|sops-nix|uninsane-dot-org)
      inputs+=("$1")
      ;;
    (*)
      echo "unknown input '$1'"
      exit 1
      ;;
  esac
}

# exec $@, unless we're in a dry-run in which case just print what would be done
doEffect() {
  if [ -n "$dryRun" ]; then
    echo "dry-run: $*"
  else
    "$@"
  fi
}

parseArgs "$@"

echo "updating:" "${inputs[@]}"
nixFlags=()
for i in "${inputs[@]}"; do
  nixFlags+=("--update-input" "$i")
done

doEffect nix flake lock "${nixFlags[@]}"