#!/bin/bash

# Bring in the variables from SOLUTION file, supporting
# nested substitution
. SOLUTION

VARS=($(sed -nE "s,(^[^#][^=]*).*$,\1,pg" SOLUTION))
for var in ${VARS[@]}; do
  export ${var}
done

[[ -d "templates/${OS_DISTRO}" ]] || {
  echo "Unrecognized OS_DISTRO: '${OS_DISTRO}'"
  exit -1
}


if [[ -e "Dockerfile.solution.${OS_DISTRO}-${OS_RELEASE}" ]]; then
  SOLUTION_SUFFIX=".${OS_DISTRO}-${OS_RELEASE}"
elif [[ -e "Dockerfile.solution.${OS_DISTRO}" ]]; then
  SOLUTION_SUFFIX=".${OS_DISTRO}"
else
  SOLUTION_SUFFIX=""
fi

[[ "${SOLUTION_SUFFIX}" == "" ]] && {
  cat << EOF

The following Dockerfile.solutions were checked, but do not exist:

* Dockerfile.solution.${OS_DISTRO}
* Dockerfile.solution.${OS_DISTRO}-${OS_RELEASE}

EOF
}

REGISTRY_OS_AMR=amr-registry.caas.intel.com/vtt-osgc/os/
export REGISTRY_OS=${REGISTRY_OS:-${REGISTRY_OS_AMR}}
if [[ "${REGISTRY_OS}" == "external" ]]; then
  export REGISTRY_OS=
fi
export DOCKERFILE="Dockerfile${SOLUTION_SUFFIX}"
export SOLUTION="Dockerfile.solution${SOLUTION_SUFFIX}"
export PACKAGE_DISTRO
VARS+=(DOCKERFILE SOLUTION BUILD REGISTRY_OS PACKAGE_DISTRO)

if [[ "${BUILD}" != "" ]] && [[ "${BUILD}" != "N/A" ]]; then
  # Override PACKAGE_REPOSITORY as it won't be used -- instead a file
  # repository will be configured
  PACKAGE_REPOSITORY=file:///repos/${BUILD}
  PACKAGE_STREAM="N/A"

  # ARTIFACTORY_PATH is set by scripts/build-dockerfile.sh based on the value of
  # BUILD. For example, agama-ci-releases_20.4 becomes agama-ci-releases/20.4
  #
  # sh (the shell interpreter of Docker) does not support subsitution so
  # this can't be done within the Dockerfile itself.
  #
  ARTIFACTORY_PATH=${BUILD%-*}                   # Prune off -405
  ARTIFACTORY_PATH=${ARTIFACTORY_PATH#agama-ci-} # Prune of agama-ci-
  ARTIFACTORY_PATH=${ARTIFACTORY_PATH//_/\/}     # releases_20.4 => releases/20.4

  # Since we're already making special variables, scripts/build-dockerfile.sh
  # will also set ARTIFACTORY_RELEASE based on the OS_RELEASE name if Ubuntu
  # is being used (eg., 20.04 for focal, etc)
  case ${OS_RELEASE} in
  focal) ARTIFACTORY_RELEASE=20.04 ;;  # Focal Fossa
  groovy) ARTIFACTORY_RELEASE=20.10 ;; # Groovy Gorilla
  esac
  ARTIFACTORY_RELEASE=${ARTIFACTORY_RELEASE:-${OS_RELEASE}}

  VARS+=(ARTIFACTORY_PATH ARTIFACTORY_RELEASE)

  export ARTIFACTORY_RELEASE
  export ARTIFACTORY_PATH

  TAG_SUFFIX=${BUILD}
else
  TAG_SUFFIX=${PACKAGE_STREAM}
fi

cat << EOF
Using:

  ${SOLUTION}

To generate:

  ${DOCKERFILE}

Values used:

EOF

# Build a SHELL-FORMAT value to pass to envsubst.
# Only those variables matched in SHELL-FORMAT will
# be escaped by envsubst.
ENV=''
for var in ${VARS[@]}; do
  echo "  ${var} = ${!var}"
  ENV=${ENV}'$'${var}
done

SNIPPETS=()
# Create a list of all the templates for this distro
for snippet in templates/??-*.in templates/${OS_DISTRO}/??-*.in; do
  if [[ "${TEMPLATE_IGNORE}" != "" ]] && [[ ${snippet} =~ ${TEMPLATE_IGNORE} ]]; then
    continue
  fi

  SNIPPETS+=($snippet)
done

# Add in the list of templates from the release sub-directory
# removing from the base distro if a name conflict
if [[ -d templates/${OS_DISTRO}/${OS_RELEASE} ]]; then
  for snippet in templates/${OS_DISTRO}/${OS_RELEASE}/??-*.in; do
    if [[ "${TEMPLATE_IGNORE}" != "" ]] && [[ ${snippet} =~ ${TEMPLATE_IGNORE} ]]; then
      continue
    fi
    SNIPPETS=(${SNIPPETS[@]%%*$(basename ${snippet})})
    SNIPPETS+=(${snippet})
  done
fi

# Filter to include either ??-repositories-intel.in or 
# ??-local-file-intel-repo.in based on if a BUILD was specified.
#
TMP=()
for snippet in ${SNIPPETS[@]}; do
  if [[ "${BUILD}" != "" ]] && [[ "${BUILD}" != "N/A" ]]; then
    # If a build was specified, then do not include ??-repositories-intel.in and
    if [[ ${snippet} =~ ..-repositories-intel-com.in ]]; then
      continue
    fi
  else
    # If a build was NOT specified, then do not include ??-local-file-intel-repo.in and
    if [[ ${snippet} =~ ..-local-file-intel-repo.in ]]; then
      continue
    fi
  fi

  # If NO_REPO is set, then use neither repository
  if (( NO_REPO )); then
    if [[ ${snippet} =~ ..-local-file-intel-repo.in ]] ||
       [[ ${snippet} =~ ..-repositories-intel-com.in ]]; then
      continue
    fi
  fi
  TMP+=(${snippet})
done
SNIPPETS=(${TMP[@]})

# Sort the entries by the filename by rewriting
# the entries as FILENAME DIRNAME
# Then read the sorted information back out and
# re-create the filepath, storing the results in
# the TEMPLATES array
TEMPLATES=($(for snippet in ${SNIPPETS[@]}; do
  echo $(basename $snippet) $(dirname $snippet)
done | sort | while read base dir; do
  echo ${dir}/${base}
done))

# Remove the Dockerfile if it exists; should check
# if it is clean first, and abort if not.
#
[ -e ${DOCKERFILE} ] && rm ${DOCKERFILE}

cat << EOM > ${DOCKERFILE}
# syntax=docker/dockerfile:1.2
# Enable secrets
#
# DO NOT EDIT THIS DOCKERFILE
#
# This file is auto-generated via scripts/build-dockerfile
# by using environment substitution while concatenating the
# contents of templates/*, and then adding the contents
# of ${SOLUTION}
#
# Most solution specific changes should be isolated in
# ${SOLUTION}. After making changes, you can then re-run
# scripts/build-dockerfile
#
EOM

for snippet in ${TEMPLATES[@]}; do
  cat << EOM >> ${DOCKERFILE}

#
# Template from ${snippet}
#
EOM
  envsubst ${ENV} < $snippet >> ${DOCKERFILE}
done

cat << EOM >> ${DOCKERFILE}

#
# Solution begins here (from ${SOLUTION})
#
EOM

envsubst ${ENV} < ${SOLUTION} >> ${DOCKERFILE}

cat << EOM >> ${DOCKERFILE}

#
# Standard ending begins here (from templates/ending.in)
#
EOM

envsubst ${ENV} < templates/ending.in >> ${DOCKERFILE}

cat << EOM

To build the image, you can run:

  export TAG=${OS_DISTRO}-${TAG_SUFFIX}
  scripts/build-image.sh

EOM