#!/bin/bash
set -euo pipefail
DEBIAN_FRONTEND=noninteractive

# System deps (already installed via cloud-init but idempotent)
apt-get update -qq
apt-get install -y -qq build-essential curl git \
  libgmp-dev libffi-dev zlib1g-dev libncurses-dev libtinfo-dev pkg-config

# GHCup — non-interactive bootstrap
# Primary version (9.8.4) is the default; secondary (9.6.6) covers LTS 22/23.
# Skip Stack (cabal covers 95% of projects) and HLS (saves ~2 GB image size).
GHC_PRIMARY="${GHC_PRIMARY_VERSION:-9.8.4}"
GHC_SECONDARY="${GHC_SECONDARY_VERSION:-9.6.6}"
CABAL_VERSION="${CABAL_VERSION:-3.12.1.0}"

export BOOTSTRAP_HASKELL_NONINTERACTIVE=1
export BOOTSTRAP_HASKELL_GHC_VERSION="$GHC_PRIMARY"
export BOOTSTRAP_HASKELL_CABAL_VERSION="$CABAL_VERSION"
export BOOTSTRAP_HASKELL_INSTALL_STACK=0   # not needed; cabal suffices
export BOOTSTRAP_HASKELL_INSTALL_HLS=0    # ~2 GB — skip for build-only image

curl --proto '=https' --tlsv1.2 -sSf https://get-ghcup.haskell.org \
  | runuser -l build -c 'sh -s -- --no-modify-path'

# Add ghcup env to build user profile
echo '. "$HOME/.ghcup/env"' >> /home/build/.bashrc
echo '. "$HOME/.ghcup/env"' >> /home/build/.profile

# Install secondary GHC version (~500 MB, shared GHCup base — worth it)
runuser -l build -c "source ~/.ghcup/env && ghcup install ghc $GHC_SECONDARY"

# Ensure primary is the default
runuser -l build -c "source ~/.ghcup/env && ghcup set ghc $GHC_PRIMARY"

# Pre-warm cabal package db (saves 2-3 min on first real build)
runuser -l build -c 'source ~/.ghcup/env && cabal update'

# Verify both versions present
runuser -l build -c "source ~/.ghcup/env && ghc --version && cabal --version"
runuser -l build -c "source ~/.ghcup/env && ghcup run --ghc $GHC_SECONDARY -- ghc --version"