#!/bin/sh

fail() {
  echo "${@}" >&2
  exit 1
}

on_tag() {
  if [ -n "$CURRENT_TAG" ]; then
    echo "${@}"
    eval "${@}"
    return $?
  else
    return 0
  fi
}

fail_on_error() {
  "${@}"

  exit=$?
  if [ "$exit" -ne "0" ]; then
    fail "${@} exited with $exit"
  fi

  return 0
}

verify_environment() {
  if [ -z "$TRAVIS_OS_NAME" ]; then
    fail "\$TRAVIS_OS_NAME is not set or empty."
  fi
}

verify_linux_environment() {
  if [ -z "$ARCH" ]; then
    fail "\$ARCH is not set or empty."
  fi

  if [ -z "$ARCH_CMD" ]; then
    fail "\$ARCH_CMD is not set or empty."
  fi
}

on_os() {
  os="$1"
  shift

  if [ -z "$CI_NIX_SHELL" ]; then
    verify_environment

    if [ "$TRAVIS_OS_NAME" = "$os" ]; then
      echo "${@}"
      eval "${@}"
      return $?
    else
      return 0
    fi
  else
    return 0
  fi
}

on_linux() {
  fail_on_error on_os "linux" "${@}"
}

on_osx() {
  fail_on_error on_os "osx" "${@}"
}

on_nix_shell_eval() {
  if [ -n "$CI_NIX_SHELL" ]; then
    echo "${@}"
    eval "${@}"
    return $?
  else
    return 0
  fi
}

on_nix_shell() {
  fail_on_error on_nix_shell_eval "${@}"
}

on_github() {
  if [ "$GITHUB_ACTIONS" = "true" ]; then
    eval "${@}"
    return $?
  else
    return 0
  fi
}

prepare_system() {
  on_linux 'echo '"'"'{"ipv6":true, "fixed-cidr-v6":"2001:db8:1::/64"}'"'"' | sudo tee /etc/docker/daemon.json'
  on_linux sudo service docker restart
}

build() {
  with_build_env 'make std_spec clean threads=1 junit_output=.junit/std_spec.xml'

  case $ARCH in
    i386)
      with_build_env 'make crystal threads=1'
      with_build_env 'SPEC_SPLIT="0%4" make std_spec threads=1 junit_output=.junit/std_spec.0.xml'
      with_build_env 'SPEC_SPLIT="1%4" make std_spec threads=1 junit_output=.junit/std_spec.1.xml'
      with_build_env 'SPEC_SPLIT="2%4" make std_spec threads=1 junit_output=.junit/std_spec.2.xml'
      with_build_env 'SPEC_SPLIT="3%4" make std_spec threads=1 junit_output=.junit/std_spec.3.xml'

      parts=16
      i=0
      while [ $i -lt $parts ]; do
        with_build_env "CRYSTAL_SPEC_COMPILER_THREADS=1 SPEC_SPLIT=\"$i%$parts\" make compiler_spec threads=1 junit_output=.junit/compiler_spec.$i.xml"
        i=$((i + 1))
      done

      with_build_env 'make primitives_spec threads=1 junit_output=.junit/primitives_spec.xml'
      with_build_env 'make docs threads=1'
      ;;
    *)
      with_build_env 'make crystal primitives_spec std_spec compiler_spec docs threads=1 junit_output=.junit/spec.xml DOCS_OPTIONS="--json-config-url=/api/versions.json --canonical-base-url=https://crystal-lang.org/api/latest/"'
      ;;
  esac

  with_build_env 'make samples'
  with_build_env 'CRYSTAL_OPTS=--debug make samples'
}

format() {
  with_build_env 'make clean crystal format threads=1 check=1'
}

prepare_build() {
  on_linux verify_linux_environment

  on_osx curl -L https://github.com/crystal-lang/crystal/releases/download/1.5.0/crystal-1.5.0-1-darwin-universal.tar.gz -o ~/crystal.tar.gz
  on_osx 'pushd ~;gunzip -c ~/crystal.tar.gz | tar xopf -;mv crystal-1.5.0-1 crystal;popd'

  # These commands may take a few minutes to run due to the large size of the repositories.
  # This restriction has been made on GitHub's request because updating shallow
  # clones is an extremely expensive operation due to the tree layout and
  # traffic of Homebrew/homebrew-core and Homebrew/homebrew-cask. We don't do
  # this for you automatically to avoid repeatedly performing an expensive
  # unshallow operation in CI systems (which should instead be fixed to not use
  # shallow clones). Sorry for the inconvenience!
  on_osx git -C /usr/local/Homebrew/Library/Taps/homebrew/homebrew-core fetch --unshallow
  on_osx git -C /usr/local/Homebrew/Library/Taps/homebrew/homebrew-cask fetch --unshallow

  on_osx brew update --preinstall
  on_osx brew bundle --no-lock

  # Install a recent bash version for nix-shell.
  # macos ships with an ancient one.
  if [ `uname` = "Darwin" ]; then
    on_nix_shell "brew install bash"
  fi
  # initialize nix environment
  on_nix_shell nix-shell

  # Note: brew link --force might show:
  #   Warning: Refusing to link macOS-provided software: llvm
  #
  #   If you need to have llvm first in your PATH run:
  #     echo 'export PATH="/usr/local/opt/llvm/bin:$PATH"' >> ~/.bash_profile
  #
  # This is added in the .circleci/config.yml

  on_tag verify_version
}

verify_version() {
  # If building a tag, check it matches with file
  FILE_VERSION=`cat ./src/VERSION`

  if [ "$FILE_VERSION" != "$CURRENT_TAG" ]
  then
    fail "VERSION ($FILE_VERSION) does not match GIT TAG ($CURRENT_TAG)"
  fi
}

with_build_env() {
  command="$1"
  on_github "echo '::group::$1'"

  # Ensure non GMT timezone
  export TZ="America/New_York"

  on_linux verify_linux_environment

  export DOCKER_TEST_PREFIX="${DOCKER_TEST_PREFIX:=crystallang/crystal:1.5.0}"

  case $ARCH in
    x86_64)
      export DOCKER_TEST_IMAGE="$DOCKER_TEST_PREFIX-build"
      ;;
    x86_64-musl)
      export DOCKER_TEST_IMAGE="$DOCKER_TEST_PREFIX-alpine-build"
      ;;
    i386)
      export DOCKER_TEST_IMAGE="$DOCKER_TEST_PREFIX-i386-build"
      ;;
  esac

  on_linux docker run \
    --rm -t \
    -u $(id -u) \
    -v $PWD:/mnt \
    -v /etc/passwd:/etc/passwd \
    -v /etc/group:/etc/group \
    -w /mnt \
    -e CRYSTAL_CACHE_DIR="/tmp/crystal" \
    -e SPEC_SPLIT_DOTS \
    "$DOCKER_TEST_IMAGE" \
    "$ARCH_CMD" /bin/sh -c "'$command'"

  on_osx sudo systemsetup -settimezone $TZ
  on_osx PATH="~/crystal/bin:\$PATH" \
    CRYSTAL_LIBRARY_PATH="~/crystal/embedded/lib" \
    CRYSTAL_CACHE_DIR="/tmp/crystal" \
    /bin/sh -c "'$command'"

  on_nix_shell nix-shell --pure $CI_NIX_SHELL_ARGS --run "'TZ=$TZ $command'"

  on_github echo "::endgroup::"
}

usage() {
  cat <<EOF
bin/ci [-h|--help] command [parameter ...]

Helper script to prepare and run the testsuite on Travis CI.

Commands:
  prepare_system          setup any necessaries repositories etc.
  prepare_build           download and extract any dependencies needed for the build
  build                   run specs, build crystal, build samples, build the docs
  format                  build crystal, run format check
  with_build_env command  run command in the build environment
  help                    display this

EOF
}

command="$1"
shift
case $command in
  prepare_system)
    prepare_system
    ;;
  prepare_build)
    prepare_build
    ;;
  with_build_env)
    target_command="${@}"
    with_build_env "$target_command"
    ;;
  build)
    build
    ;;
  format)
    format
    ;;
  -h|--help|help)
    usage
    ;;
  *)
    if [ -n "$command" ]; then
      fail "Unknown command $command"
    else
      usage
      exit 1
    fi
    ;;
esac