find a list of apps you installed that were not using brew

findbrew.sh

#!/bin/bash

# Use brew install --cask --force x y z to reinstall the apps found with brew

# Get list of all installed applications on Mac
IFS=$'\n' app_list=($(mdfind "kMDItemContentTypeTree == 'com.apple.application' && kMDItemCFBundleIdentifier != 'com.apple.Installer' && kMDItemCFBundleIdentifier != 'com.apple.systempreferences'"))

# Get the response of the Brew Cask JSON API
brew_cask_api_response=$(curl -s https://formulae.brew.sh/api/cask.json)

# Get the output of "brew list"
brew_list_output=$(brew list)

# Loop through each application and check if it's installed with Brew
for app in "${app_list[@]}"; do
    # Get the application name from its path
    app_name=$(basename "$app")
    brew_name=$(basename "$app" | sed 's/\.app//' | tr '[:upper:]' '[:lower:]' | sed 's/ /-/g')

    # Check if the application is installed with Brew
    if echo "$brew_cask_api_response" | rg -q "\"$app_name\""; then
        if echo "$brew_list_output" | rg -q "$brew_name"; then
            echo ""
        else
            echo "$app_name is not installed with Brew."
        fi
    fi
done