find-adoptable-casks.sh

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

APP_DIRS=(
  "/Applications"
  "$HOME/Applications"
)

if ! command -v brew >/dev/null 2>&1; then
  echo "Error: Homebrew not found in PATH" >&2
  exit 1
fi

# Cache list of installed casks
mapfile -t INSTALLED_CASKS < <(brew list --cask 2>/dev/null || true)

is_installed_cask() {
  local token="$1"
  for c in "${INSTALLED_CASKS[@]}"; do
    [[ "$c" == "$token" ]] && return 0
  done
  return 1
}

guess_token_from_appname() {
  local appname="$1"
  echo "$appname" \
    | tr 'A-Z' 'a-z' \
    | sed -E 's/[^a-z0-9+]+/-/g; s/^-+//; s/-+$//'
}

test_cask_dryrun() {
  local cask="$1"
  # quiet dry run test; return code determines success
  if brew install --cask --adopt --dry-run "$cask" >/dev/null 2>&1; then
    return 0
  fi
  return 1
}

echo "# These casks passed a dry-run and are adoptable:"
echo

for dir in "${APP_DIRS[@]}"; do
  [[ -d "$dir" ]] || continue

  while IFS= read -r -d '' app; do
    app_basename="$(basename "$app")"
    appname="${app_basename%.app}"

    token_guess="$(guess_token_from_appname "$appname")"
    chosen_cask=""

    # 1. Try direct token guess
    if [[ -n "$token_guess" ]] && ! is_installed_cask "$token_guess"; then
      if brew info --cask "$token_guess" >/dev/null 2>&1; then
        chosen_cask="$token_guess"
      fi
    fi

    # 2. Try searching by name
    if [[ -z "$chosen_cask" ]]; then
      search_results="$(brew search --cask "$appname" 2>/dev/null | head -n 5 || true)"
      while IFS= read -r candidate; do
        [[ -z "$candidate" ]] && continue
        is_installed_cask "$candidate" && continue
        if brew info --cask "$candidate" >/dev/null 2>&1; then
          chosen_cask="$candidate"
          break
        fi
      done <<< "$search_results"
    fi

    # 3. Only print if it passes a dry-run install
    if [[ -n "$chosen_cask" ]]; then
      if test_cask_dryrun "$chosen_cask"; then
        echo "brew install --cask --adopt \"$chosen_cask\"   # $app_basename"
      fi
    fi

  done < <(find "$dir" -maxdepth 1 -type d -name '*.app' -print0)

done