#!/bin/sh

# == Objective ==
# Create a virgin chroot
# Copy in build (make.conf) and port (/var/db/ports) configuration
# Compute build/runtime dependencies for leaf port
# Install build/runtime dependency packages, if they exist from a previous leaf port build
# Build a single leaf port
# Create packages for leaf port and its runtime dependencies
# Create a separate set of packages for its build-time dependencies, to use for later leaf port builds

ROOT="$(realpath "$(dirname "${0}")")"
TARGET=amd64
CONFIG=SS4200

meh() { printf " \033[1;32m*\033[0m %s\n" "${*}"; }
omg() { printf " \033[1;33m*\033[0m %s\n" "${*}"; }
wtf() { printf " \033[1;31m* FAIL\033[0m %s\n" "${*}"; exit 1; }

tgtdir="${TARGET}/${CONFIG}"
build="${ROOT}/port/root" # Location of build environment
date="$(date +%Y%m%d)"
srctree="${ROOT}/${tgtdir}" # Virgin build env will be copied from here

# Prepare a build chroot
prepare() {
  mount | grep -q "${build}" && wtf "Stuff is mounted under ${build}; cannot continue"
  
  # Put cleanup trap here so that an abort during prepare properly cleans up
  trap "cleanup" exit hup int term kill

  meh "Preparing build environment"
  mkdir -p "${build}" || wtf
  cd "${srctree}"; find . | cpio -p "${build}" || wtf
  # Hold packages for build deps
  mkdir -p "${build}/pkg/build" || wtf
  # Hold packages for runtime deps
  mkdir -p "${build}/pkg/run" || wtf

  meh "Mounting chroot directories" || wtf
  mkdir -p "${build}/usr/ports" || wtf
  mkdir -p "${build}/usr/obj" || wtf
  mount -t devfs devfs "${build}/dev" || wtf
  mount -t nullfs -r /usr/src "${build}/usr/src" || wtf # Just in case a port needs kernel sources
  mount -t nullfs -r /usr/ports "${build}/usr/ports" || wtf

  if [ -d "${world}/config" ]
  then
    meh "Installing build-time configuration"
    # Install make.conf
    [ -f "${world}/config/make.conf" ] && cp "${world}/config/make.conf" "${build}/etc/" || wtf
    # Install port options files
    [ -d "${world}/config/ports" ] && ( cd "${world}/config/ports"; find . -type d -o -type f -name 'options' | cpio -p "${build}/var/db/ports/" ) || wtf
  fi
}

# Evaluate a bit of code within the ${build} chroot
# If ${chroot_env} is set, replace environment with it before chrooting
chroot_eval() {
  [ "${chroot_env}" ] && env="env -i ${chroot_env}"
  ${env} chroot "${build}" /bin/sh
}

# Clean up and remove the build chroot
cleanup() {
  meh "Cleaning up"
  umount -f "${build}/usr/ports"
  umount -f "${build}/usr/src"
  umount -f "${build}/dev"
  mount |grep -q "${build}" && wtf "Stuff is still mounted under ${build}; not removing"
  chflags -R noschg "${build}"
  rm -Rf "${build}"
}

prepare
chroot_eval
cleanup