From 4430de0a4950f7cec07a6e21307d01521b5e5bb0 Mon Sep 17 00:00:00 2001
From: fruffy <fruffy@nyu.edu>
Date: Tue, 27 Feb 2024 20:24:21 -0500
Subject: [PATCH] Fun with GPTs.

---
 tools/install_mac_deps.sh | 66 ++++++++++++++++++++++++++-------------
 1 file changed, 45 insertions(+), 21 deletions(-)

diff --git a/tools/install_mac_deps.sh b/tools/install_mac_deps.sh
index 3a1271ee82c..118ca3cbca5 100755
--- a/tools/install_mac_deps.sh
+++ b/tools/install_mac_deps.sh
@@ -1,39 +1,63 @@
 #! /bin/bash
 
-# Script for building P4C on MacOS.
+# Script to install P4C dependencies on MacOS.
 
 set -e  # Exit on error.
 set -x  # Make command execution verbose
 
-
-# Set up Homebrew differently for arm64.
-if [[ $(uname -m) == 'arm64' ]]; then
+# Check if brew shellenv command is already in zprofile
+if ! grep -q 'brew shellenv' ~/.zprofile; then
+  # Set up Homebrew differently for arm64.
+  if [[ $(uname -m) == 'arm64' ]]; then
     (echo; echo 'eval "$(/opt/homebrew/bin/brew shellenv)"') >> ~/.zprofile
-    eval "$(/opt/homebrew/bin/brew shellenv)"
-else
+  else
     (echo; echo 'eval "$(/usr/local/bin/brew shellenv)"') >> ~/.zprofile
-    eval "$(/usr/local/bin/brew shellenv)"
+  fi
+fi
+
+# Check if Homebrew is already installed
+if ! which brew > /dev/null 2>&1; then
+  /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
 fi
 
-if [[ ! -x brew ]]; then
-    /bin/bash -c "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/HEAD/install.sh)"
+# Source zprofile only if necessary
+if ! source ~/.zprofile &> /dev/null; then
+  echo "Warning: Failed to source ~/.zprofile."
 fi
+
 HOMEBREW_PREFIX=$(brew --prefix)
 
-# Install some custom requirements on OS X using brew
-BOOST_LIB="boost@1.84"
-brew install autoconf automake bdw-gc ccache cmake \
-      libtool openssl pkg-config coreutils bison grep \
-      ${BOOST_LIB}
+# Check if any packages need installation.
+REQUIRED_PACKAGES=(autoconf automake bdw-gc ccache cmake libtool openssl pkg-config coreutils bison grep)
+MISSING_PACKAGES=()
+for package in "${REQUIRED_PACKAGES[@]}"; do
+  if ! brew list -q "$package"; then
+    MISSING_PACKAGES+=("$package")
+  fi
+done
 
-# We need to link boost and openssl.
-brew link ${BOOST_LIB} openssl
-# Prefer Homebrew's bison and grep over the macOS-provided version.
-# For Bison only `$(brew --prefix bison)/bin` seems to work...
-echo 'export PATH="$(brew --prefix bison)/bin:$PATH"' >> ~/.bash_profile
-echo 'export PATH="$HOMEBREW_PREFIX/opt/grep/libexec/gnubin:$PATH"' >> ~/.bash_profile
-source ~/.bash_profile
+# Install missing packages.
+if [[ ${#MISSING_PACKAGES[@]} -gt 0 ]]; then
+  brew install "${MISSING_PACKAGES[@]}"
+fi
 
+# Check if linking is needed
+if ! brew ls --linked --formula ${BOOST_LIB} > /dev/null 2>&1; then
+  brew link ${BOOST_LIB} openssl
+fi
+
+# Check if PATH modification is needed
+if ! grep -q "$(brew --prefix bison)/bin" ~/.bash_profile; then
+  echo 'export PATH="$(brew --prefix bison)/bin:$PATH"' >> ~/.bash_profile
+fi
+if ! grep -q "$HOMEBREW_PREFIX/opt/grep/libexec/gnubin" ~/.bash_profile; then
+  echo 'export PATH="$HOMEBREW_PREFIX/opt/grep/libexec/gnubin:$PATH"' >> ~/.bash_profile
+fi
+
+# Source bash_profile only if necessary
+if ! source ~/.bash_profile &> /dev/null; then
+  echo "Warning: Failed to source ~/.bash_profile."
+fi
 
 # Fixes for stuck grpcio installation.
 export GRPC_PYTHON_BUILD_SYSTEM_OPENSSL=1