#!/bin/sh
# Copyright (c) 2011 The Chromium OS Authors. All rights reserved.
# Use of this source code is governed by a BSD-style license that can be
# found in the LICENSE file.
#
# This script downloads and installs the basic packages that the user needs
# in developer mode. It also takes care of some configuration details
# that arise from not havin write access to the root filesystem.

# Constant definitions.
EMERGE_PACKAGES="/etc/portage/bootstrap.packages"
# Global variables.
BINHOST=""

# Check if we are root.
if [ $(/usr/bin/id -u) -ne 0 ]; then
  echo "ERROR: Can not run script."
  echo "You are not root or you did not use sudo."
  exit 1
fi

# This script should only run in developer mode or for developer images.
/usr/bin/crossystem "cros_debug?0"
CROS_DEBUG=$?

if [ ${CROS_DEBUG} -ne 1 ]; then
  echo "ERROR: Can not run script."
  echo "Chrome OS is not in developer mode."
  exit 1
fi

# Process flags.
. /usr/share/misc/shflags
DEFINE_string binhost "" \
  "URL of the binhost that emerge will use."
DEFINE_string binhost_version "" \
  "Version number to use instead of the one in /etc/lsb-release."
DEFINE_boolean uninstall "${FLAGS_FALSE}" \
  "Remove all installed packages."
DEFINE_boolean reinstall "${FLAGS_FALSE}" \
  "Remove all installed packages and re-bootstrap emerge."

FLAGS "$@" || exit 1

set -e

# Here we simply wipe /usr/local/* since that it's the only directory in which
# packages are installed to.
remove_installed_packages() {
  read -p "Remove all installed packages now (y/n)?" reply
  if [ "${reply}" = "y" ]; then
    rm -rf --one-file-system /usr/local/*
    echo "Removed all installed packages."
  else
    echo "Operation cancelled."
    exit 0
  fi
}

if [ ${FLAGS_uninstall} -eq ${FLAGS_TRUE} \
     -o ${FLAGS_reinstall} -eq ${FLAGS_TRUE} ]; then
  remove_installed_packages
  if [ ${FLAGS_uninstall} -eq ${FLAGS_TRUE} ]; then
    exit 0
  else
    echo "Reinstalling emerge."
  fi
fi

# Check if packages are already installed.
if [ -d /usr/local/etc/portage ]; then
  echo "ERROR: Directory /urs/local/etc/portage exists."
  echo "Did you mean dev_install --reinstall?"
  exit 1
fi

# Get the portage configuration variables.
. /etc/portage/make.profile/make.defaults

# Create this loop so uncompressed files in /usr/local/usr/* will be reachable
# through /usr/local*.
if [ ! -d /usr/local/usr ]; then
  ln -s /usr/local /usr/local/usr
fi

if [ ! -d /usr/local/local ]; then
  ln -s /usr/local /usr/local/local
fi

get_binhost() {
  if [ -n "${FLAGS_binhost}" ]; then
    BINHOST="${FLAGS_binhost}"
  else
    local release_number
    # Get prefix for binhost.
    . /etc/portage/repository.conf

    if [ -n "${FLAGS_binhost_version}" ]; then
      release_number="${FLAGS_binhost_version}"
    else
      # Get the release number.
      release_number=`grep "CHROMEOS_RELEASE_VERSION" /etc/lsb-release |
                      grep -Eo "[0-9]\.[0-9]+\.[0-9]+"`
    fi
    BINHOST="${PREFIX_BINHOST}full-${release_number}.0/packages"
  fi
}

# Get the static Python binary and portage (emerge script and python modules).
download_bootstrap_packages() {
  # Download packages that python/emerge require into /usr/local/bootsrap.
  while read line; do
    local package_url
    local directory
    local package_file
    package_url="${BINHOST}/$line.tbz2"
    directory=`echo "${line}" | cut -d"/" -f1`
    package_file="${PKGDIR}/$line.tbz2"
    mkdir -p -m 0755 "${PKGDIR}/${directory}"
    echo "Downloading ${package_url}"
    curl -o "${package_file}" "${package_url}"
    cur_exit_code=$?
    if [ ${curl_exit_code} -ne 0 ]; then
      echo "ERROR: Could not download package."
      echo "Command wget -nv -N -nd -P ${PKGDIR}/" \
           "${directory} ${package_url} failed."
      exit 1
    fi
    echo "Extracting ${package_file}"
    # Ignore std error output about trailing garbage after EOF.
    tar -C "/usr/local/" -xjf "${package_file}" 2>/dev/null
    tar_exit_code=$?
    if [ ${tar_exit_code} -ne 0 ]; then
      echo "ERROR: Could not extract package."
      echo "Command tar -C /usr/local -xjf ${package_file} failed."
      exit 1
    fi
  done < "${EMERGE_PACKAGES}"
}

# Configure emerge in /usr/local.
configure_emerge() {
  # Copy emerge configuration to /usr/local.
  mkdir -p -m 0755 /usr/local/etc/portage
  cp /etc/portage/make.profile/make.conf /usr/local/etc/portage
  ln -s /etc/portage/make.profile /usr/local/etc/portage/make.profile

  # Create the directories defined in the portage config files. Permissions are
  # consistent with the other directories in /usr/local, which is a bind mount
  # for /mnt/stateful_partition/dev_image.
  mkdir -p -m 0755 "${PORTDIR}"
  mkdir -p -m 0755 "${PKGDIR}"
  mkdir -p -m 0755 "${DISTDIR}"
  mkdir -p -m 0755 "${RPMDIR}"
  mkdir -p -m 0755 "${PORTAGE_TMPDIR}"
  mkdir -p -m 0755 "${BUILD_PREFIX}"

  echo "PORTAGE_BINHOST=${BINHOST}" >> /usr/local/etc/portage/make.conf

  # Add LD_LIBRARY_PATH within ebuild.sh.
  # TODO(arkaitzr): find out a cleaner way to do this.
  sed -i '3 a\export LD_LIBRARY_PATH=/usr/local/lib' \
      /usr/local/lib/portage/bin/ebuild.sh
}

install_optional_packages() {
  local reply
  read -p "Install chromeos-dev package now (y/n)?" reply
  if [ "${reply}" = "y" ]; then
    # TODO(arkaitzr): remove emergeing perf once the packages dependencies are
    # correct. Now chromeos-dev does not install because of missing
    # virtual/perf although dev-util/perf is available.
    emerge dev-util/perf
    emerge chromeos-dev
  else
    echo "You can install chromeos-dev later by typing the command:"
    echo "emerge chromeos-dev"
  fi
}

echo "Starting installation of developer packages."
echo "First, we download the necessary files."
get_binhost
download_bootstrap_packages

echo "Files downloaded, configuring emerge."
configure_emerge

echo "Emerge installation complete. Installing additional optional packages."
install_optional_packages

echo "dev_install done. Enjoy!"