install-zsh-stack-macos.sh

#!/usr/bin/env bash
# install-zsh-stack-macos.sh — Homebrew + zsh + Oh My Zsh + plugins (macOS)
set -euo pipefail

THEME="${THEME:-bira}"
echo "# → Theme to install: $THEME"

# 1) Homebrew
if ! command -v brew >/dev/null 2>&1; then
  echo "🍺 Installing Homebrew..."
  /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
  if [[ -x /opt/homebrew/bin/brew ]]; then
    eval "$(/opt/homebrew/bin/brew shellenv)"
  elif [[ -x /usr/local/bin/brew ]]; then
    eval "$(/usr/local/bin/brew shellenv)"
  fi
fi
echo "🍺 Updating Homebrew..."
brew update
brew upgrade

echo "🍺 Installing git, zsh, curl..."
brew install git zsh curl

# 2) Oh My Zsh (unattended)
export RUNZSH=no CHSH=no KEEP_ZSHRC=yes
echo "💡 Installing Oh My Zsh..."
curl -fsSL https://raw.githubusercontent.com/ohmyzsh/ohmyzsh/master/tools/install.sh | sh -s -- --unattended

# 3) Plugins (no declare -A; no read -d)
ZSH_DIR="$HOME/.oh-my-zsh"
CUSTOM_DIR="${ZSH_CUSTOM:-$ZSH_DIR/custom}"
mkdir -p "$CUSTOM_DIR/plugins"

echo "🔌 Cloning plugins into $CUSTOM_DIR/plugins ..."
while read -r name url; do
  [[ -z "${name:-}" || -z "${url:-}" ]] && continue
  [[ -d "$CUSTOM_DIR/plugins/$name" ]] && continue
  git clone --depth=1 "$url" "$CUSTOM_DIR/plugins/$name"
done <<'EOF'
zsh-autosuggestions https://github.com/zsh-users/zsh-autosuggestions
zsh-syntax-highlighting https://github.com/zsh-users/zsh-syntax-highlighting
fast-syntax-highlighting https://github.com/zdharma-continuum/fast-syntax-highlighting
zsh-autocomplete https://github.com/marlonrichert/zsh-autocomplete
EOF

# 4) Theme (BSD sed uses -i '')
echo "🎨 Setting theme \"$THEME\" ..."
touch "$HOME/.zshrc"
if grep -q '^ZSH_THEME=' "$HOME/.zshrc"; then
  sed -i '' "s/^ZSH_THEME=.*/ZSH_THEME=\"$THEME\"/" "$HOME/.zshrc"
else
  sed -i '' "1i\\
ZSH_THEME=\"$THEME\"
" "$HOME/.zshrc"
fi

# 5) Plugins line (recommended order)
ORDERED_PLUGINS=(git zsh-autosuggestions zsh-syntax-highlighting fast-syntax-highlighting zsh-autocomplete)
echo "🧩 Writing plugins line ..."
if grep -q '^plugins=' "$HOME/.zshrc"; then
  sed -i '' "s/^plugins=.*/plugins=(${ORDERED_PLUGINS[*]})/" "$HOME/.zshrc"
else
  printf '\nplugins=(%s)\n' "${ORDERED_PLUGINS[*]}" >> "$HOME/.zshrc"
fi

# 6) Make Homebrew zsh default shell
BREW_PREFIX="$(brew --prefix)"
ZSH_PATH="$BREW_PREFIX/bin/zsh"
echo "🐚 Ensuring $ZSH_PATH is in /etc/shells ..."
grep -qxF "$ZSH_PATH" /etc/shells || echo "$ZSH_PATH" | sudo tee -a /etc/shells >/dev/null

if [[ "${SHELL:-}" != "$ZSH_PATH" ]]; then
  echo "🔁 Changing login shell to $ZSH_PATH ..."
  chsh -s "$ZSH_PATH"
fi

echo -e "\n✅ Done. Open a new Terminal/iTerm window to use zsh with your theme and plugins."