#!/bin/bash
# Copyright 2017, Rackspace US, Inc.
#
# Licensed under the Apache License, Version 2.0 (the "License");
# you may not use this file except in compliance with the License.
# You may obtain a copy of the License at
#
#     http://www.apache.org/licenses/LICENSE-2.0
#
# Unless required by applicable law or agreed to in writing, software
# distributed under the License is distributed on an "AS IS" BASIS,
# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
# See the License for the specific language governing permissions and
# limitations under the License.

## Shell Opts ----------------------------------------------------------------
set -e

## Variables -----------------------------------------------------------------

# The options file for the venv
ROLE_VENV_REQUIREMENTS_FILE="${1}"

## Functions -----------------------------------------------------------------

usage() {
    cat <<EOF

    Usage:
    ${0} <path to configuration options file>

EOF
}

## Main ----------------------------------------------------------------------

# Validate that an options file as been provided
if [[ -z "${ROLE_VENV_REQUIREMENTS_FILE}" ]]; then
  usage
  exit 1
fi

# Source the options file
source "${ROLE_VENV_REQUIREMENTS_FILE}"

# Output the beginning of the build
echo -n "Building venv ${ROLE_VENV_FILE}..."

# Set the log file path
ROLE_VENV_LOG="/var/log/repo/venv_build_${ROLE_VENV_FILE}.log"

# Begin the venv build
pushd "{{ repo_build_venv_dir }}" &>/dev/null

    # If the venv achive already exists, remove it
    [[ -e "${ROLE_VENV_FILE}.tgz" ]] && rm -f "${ROLE_VENV_FILE}.tgz"

    # If the venv checksum file already exists, remove it
    [[ -e "${ROLE_VENV_FILE}.checksum" ]] && rm -f "${ROLE_VENV_FILE}.checksum"

    # If the venv working directory already exists, remove it
    [[ -d "${ROLE_VENV_PATH}" ]] && rm -rf "${ROLE_VENV_PATH}"

    # If the pip build directory already exists, remove it
    [[ -d "/tmp/${ROLE_VENV_FILE}" ]] && rm -rf "/tmp/${ROLE_VENV_FILE}"

    # Create the virtualenv shell
    ${VENV_CREATE_COMMAND} "${ROLE_VENV_PATH}" &>${ROLE_VENV_LOG}

    # Create the pip build directory
    mkdir -p "/tmp/${ROLE_VENV_FILE}"

    # Activate the python virtual environment for good measure
    source "${ROLE_VENV_PATH}/bin/activate"

    # Install pip, setuptools, wheel into it
    # Rather than allow virtualenv to decide which version
    # of pip/setuptools/wheel we use, we create the virtualenv
    # without them and use get-pip.py later to install them
    # into the venv. This prevents messy upgrade/downgrade
    # failures when trying to install the versions we want.
    # We also inform get-pip.py using the --find-links option
    # that there are local wheels available so that it uses
    # them instead of reaching out to the internet unnecessarily.
    ${ROLE_VENV_PATH}/bin/python {{ repo_build_release_path }}/get-pip.py \
                                 pip setuptools wheel \
                                 --find-links {{ repo_build_release_path }} \
                                 ${PIP_INSTALL_OPTIONS} \
                                 --constraint {{ repo_build_release_path }}/requirements_constraints.txt \
                                 &>${ROLE_VENV_LOG}

    # Install the packages into the venv
    ${ROLE_VENV_PATH}/bin/pip install \
        --disable-pip-version-check \
        --quiet --quiet \
        --build "/tmp/${ROLE_VENV_FILE}" \
        ${PIP_INSTALL_OPTIONS} \
        ${PIP_INDEX_OPTIONS} \
        ${ROLE_VENV_REQUIREMENTS} \
        --log "${ROLE_VENV_LOG}"

    # Deactivate the venv for good measure
    deactivate

    # Find and remove all of the python pyc files
    find "${ROLE_VENV_PATH}" -type f -name '*.pyc' -delete 2>>${ROLE_VENV_LOG}

    # Create the archive
    tar czf "${ROLE_VENV_FILE}.tgz" -C "${ROLE_VENV_PATH}" . 2>>${ROLE_VENV_LOG}

    # Create a checksum file for the archive
    sha1sum "${ROLE_VENV_FILE}.tgz" | awk '{print $1}' > "${ROLE_VENV_FILE}.checksum" 2>>${ROLE_VENV_LOG}

    # Delete working directories
    rm -rf "${ROLE_VENV_PATH}"
    rm -rf "/tmp/${ROLE_VENV_FILE}"

popd &>/dev/null

# Output the end of the build
echo "done"