### Ensure Homebrew is loaded
loadHomebrew() {
  if ! command -v brew > /dev/null; then
    if [ -f /usr/local/bin/brew ]; then
      logg info "Using /usr/local/bin/brew" && eval "$(/usr/local/bin/brew shellenv)"
    elif [ -f "${HOMEBREW_PREFIX:-/opt/homebrew}/bin/brew" ]; then
      logg info "Using ${HOMEBREW_PREFIX:-/opt/homebrew}/bin/brew" && eval "$("${HOMEBREW_PREFIX:-/opt/homebrew}/bin/brew" shellenv)"
    elif [ -d "$HOME/.linuxbrew" ]; then
      logg info "Using $HOME/.linuxbrew/bin/brew" && eval "$("$HOME/.linuxbrew/bin/brew" shellenv)"
    elif [ -d "/home/linuxbrew/.linuxbrew" ]; then
      logg info 'Using /home/linuxbrew/.linuxbrew/bin/brew' && eval "(/home/linuxbrew/.linuxbrew/bin/brew shellenv)"
    else
      logg info 'Could not find Homebrew installation'
    fi
  fi
}

### Ensures Homebrew folders have proper owners / permissions
fixHomebrewPermissions() {
  if command -v brew > /dev/null; then
    logg info 'Applying proper permissions on Homebrew folders'
    sudo chmod -R go-w "$(brew --prefix)/share"
    BREW_DIRS="share etc/bash_completion.d"
    for BREW_DIR in $BREW_DIRS; do
      if [ -d "$(brew --prefix)/$BREW_DIR" ]; then
        sudo chown -Rf "$(whoami)" "$(brew --prefix)/$BREW_DIR"
      fi
    done
    logg info 'Running brew update --force --quiet' && brew update --force --quiet
  fi
}

### Installs Homebrew
ensurePackageManagerHomebrew() {
  if ! command -v brew > /dev/null; then
    ### Select install type based off of whether or not sudo privileges are available
    if command -v sudo > /dev/null && sudo -n true; then
      logg info 'Installing Homebrew. Sudo privileges available.'
      echo | bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)" || BREW_EXIT_CODE="$?"
    else
      logg info 'Installing Homebrew. Sudo privileges not available. Password may be required.'
      bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)" || BREW_EXIT_CODE="$?"
    fi

    ### Attempt to fix problematic installs
    if [ -n "$BREW_EXIT_CODE" ]; then
        logg warn 'Homebrew was installed but part of the installation failed to complete successfully.'
        fixHomebrewPermissions
      fi
  fi
}

### Ensures gcc is installed
ensureGcc() {
  if command -v brew > /dev/null; then
    if ! brew list | grep gcc > /dev/null; then
      logg info 'Installing Homebrew gcc' && brew install --quiet gcc
    else
      logg info 'Homebrew gcc is available'
    fi
  else
    logg error 'Failed to initialize Homebrew' && exit 1
  fi
}

# @description This function ensures Homebrew is installed and available in the `PATH`. It handles the installation of Homebrew on both **Linux and macOS**.
#     It will attempt to bypass sudo password entry if it detects that it can do so. The function also has some error handling in regards to various
#     directories falling out of the correct ownership and permission states. Finally, it loads Homebrew into the active profile (allowing other parts of the script
#     to use the `brew` command).
#
#     With Homebrew installed and available, the script finishes by installing the `gcc` Homebrew package which is a very common dependency.
ensureHomebrew() {
  loadHomebrew
  ensurePackageManagerHomebrew
  loadHomebrew
  fixHomebrewPermissions
  ensureGcc
}