#!/usr/bin/env bash
# Copyright (c) 2011 Sam Stephenson
#
# Permission is hereby granted, free of charge, to any person obtaining
# a copy of this software and associated documentation files (the
# "Software"), to deal in the Software without restriction, including
# without limitation the rights to use, copy, modify, merge, publish,
# distribute, sublicense, and/or sell copies of the Software, and to
# permit persons to whom the Software is furnished to do so, subject to
# the following conditions:
#
# The above copyright notice and this permission notice shall be
# included in all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
# EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
# MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
# NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
# LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
# OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
# WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.

RUBY_BUILD_VERSION="20120216"

set -E
exec 3<&2 # preserve original stderr at fd 3

resolve_link() {
  $(type -p greadlink readlink | head -1) "$1"
}

abs_dirname() {
  local cwd="$(pwd)"
  local path="$1"

  while [ -n "$path" ]; do
    cd "${path%/*}"
    local name="${path##*/}"
    path="$(resolve_link "$name" || true)"
  done

  pwd
  cd "$cwd"
}

build_failed() {
  { echo
    echo "BUILD FAILED"
    echo

    if ! rmdir "${TEMP_PATH}" 2>/dev/null; then
      echo "Inspect or clean up the working tree at ${TEMP_PATH}"

      if file_is_not_empty "$LOG_PATH"; then
        echo "Results logged to ${LOG_PATH}"
        echo
        echo "Last 10 log lines:"
        tail -n 10 "$LOG_PATH"
      fi
    fi
  } >&3
  exit 1
}

file_is_not_empty() {
  local filename="$1"
  local line_count="$(wc -l "$filename" 2>/dev/null || true)"

  if [ -n "$line_count" ]; then
    words=( $line_count )
    [ "${words[0]}" -gt 0 ]
  else
    return 1
  fi
}

install_package() {
  install_package_using "tarball" 1 $*
}

install_git() {
  install_package_using "git" 2 $*
}

install_package_using() {
  local package_type="$1"
  local package_type_nargs="$2"
  local package_name="$3"
  shift 3

  pushd "$TEMP_PATH" >&4
  "fetch_${package_type}" "$package_name" $*
  shift $(($package_type_nargs))
  make_package "$package_name" $*
  popd >&4

  echo "Installed ${package_name} to ${PREFIX_PATH}" >&2
}

make_package() {
  local package_name="$1"
  shift

  pushd "$package_name" >&4
  before_install_package "$package_name"
  build_package "$package_name" $*
  after_install_package "$package_name"
  fix_directory_permissions
  popd >&4
}

fetch_tarball() {
  local package_name="$1"
  local package_url="$2"

  echo "Downloading ${package_url}..." >&2
  { curl "$package_url" > "${package_name}.tar.gz"
    tar xzvf "${package_name}.tar.gz"
  } >&4 2>&1
}

fetch_git() {
  local package_name="$1"
  local git_url="$2"
  local git_ref="$3"

  echo "Cloning ${git_url}..." >&2
  { git clone --depth 1 --branch "$git_ref" "$git_url" "${package_name}"
  } >&4 2>&1
}

build_package() {
  local package_name="$1"
  shift

  if [ "$#" -eq 0 ]; then
    local commands="standard"
  else
    local commands="$*"
  fi

  echo "Installing ${package_name}..." >&2

  for command in $commands; do
    "build_package_${command}"
  done
}

build_package_standard() {
  local package_name="$1"

  if [ -z "${MAKEOPTS+defined}" ]; then
    MAKE_OPTS="$MAKEOPTS"
  elif [ -z "${MAKE_OPTS+defined}" ]; then
    MAKE_OPTS="-j 2"
  fi

  { ./configure --prefix="$PREFIX_PATH" $CONFIGURE_OPTS
    make $MAKE_OPTS
    make install
  } >&4 2>&1
}

build_package_autoconf() {
  { autoconf
  } >&4 2>&1
}

build_package_ruby() {
  local package_name="$1"

  { "$RUBY_BIN" setup.rb
  } >&4 2>&1
}

build_package_ree_installer() {
  local options=""
  if [[ "Darwin" = "$(uname)" ]]; then
    options="--no-tcmalloc"
  fi

  # Work around install_useful_libraries crash with --dont-install-useful-gems
  mkdir -p "$PREFIX_PATH/lib/ruby/gems/1.8/gems"

  { ./installer --auto "$PREFIX_PATH" --dont-install-useful-gems $options $CONFIGURE_OPTS
  } >&4 2>&1
}

build_package_rbx() {
  local package_name="$1"

  { ./configure --prefix="$PREFIX_PATH" --gemsdir="$PREFIX_PATH"
    rake install
  } >&4 2>&1
}

build_package_maglev() {
  build_package_copy

  { cd "${PREFIX_PATH}"
    ./install.sh
    cd "${PREFIX_PATH}/bin"
    echo "Creating symlink for ruby*"
    ln -fs maglev-ruby ruby
    echo "Creating symlink for irb*"
    ln -fs maglev-irb irb
  } >&4 2>&1
  echo
  echo "Run 'maglev start' to start up the stone before using 'ruby' or 'irb'"
}

build_package_jruby() {
  build_package_copy
  cd "${PREFIX_PATH}/bin"
  ln -fs jruby ruby
  install_jruby_launcher
  remove_windows_files
}

install_jruby_launcher() {
  cd "${PREFIX_PATH}/bin"
  { ./ruby gem install jruby-launcher
  } >&4 2>&1
}

remove_windows_files() {
  cd "$PREFIX_PATH"
  rm -f bin/*.exe bin/*.dll bin/*.bat bin/jruby.sh
}

build_package_copy() {
  mkdir -p "$PREFIX_PATH"
  cp -R . "$PREFIX_PATH"
}

before_install_package() {
  local stub=1
}

after_install_package() {
  local stub=1
}

fix_directory_permissions() {
  # Ensure installed directories are not world-writable to avoid Bundler warnings
  find "$PREFIX_PATH" -type d -exec chmod go-w {} \;
}

require_gcc() {
  local gcc="$(locate_gcc || true)"
  if [ -z "$gcc" ]; then
    { echo
      echo "ERROR: This package must be compiled with GCC, and we"
      echo "couldn't find a suitable \`gcc' binary on your system."
      echo "Please install GCC and try again."
      echo

      if [ "$(uname -s)" = "Darwin" ]; then
        echo "As of version 4.2, Xcode is LLVM-only and no longer"
        echo "includes GCC. You can install GCC with these binary"
        echo "packages on Mac OS X:"
        echo
        echo "https://github.com/kennethreitz/osx-gcc-installer/downloads"
        echo
      fi
    } >&3
    return 1
  fi

  export CC="$gcc"
}

locate_gcc() {
  local gcc gccs
  IFS=: gccs=($(gccs_in_path))

  verify_gcc "$CC" ||
  verify_gcc "$(command -v gcc || true)" || {
    for gcc in "${gccs[@]}"; do
      verify_gcc "$gcc" && break || true
    done
  }

  return 1
}

gccs_in_path() {
  local gcc path paths
  local gccs=()
  IFS=: paths=($PATH)

  shopt -s nullglob
  for path in "${paths[@]}"; do
    for gcc in "$path"/gcc-*; do
      gccs["${#gccs[@]}"]="$gcc"
    done
  done
  shopt -u nullglob

  printf :%s "${gccs[@]}"
}

verify_gcc() {
  local gcc="$1"
  if [ -z "$gcc" ]; then
    return 1
  fi

  local version="$("$gcc" --version || true)"
  if [ -z "$version" ]; then
    return 1
  fi

  if echo "$version" | grep LLVM >/dev/null; then
    return 1
  fi

  echo "$gcc"
}

version() {
  echo "ruby-build ${RUBY_BUILD_VERSION}"
}

usage() {
  { version
    echo "usage: ruby-build [-v|--verbose] definition prefix"
    echo "       ruby-build --definitions"
  } >&2

  if [ -z "$1" ]; then
    exit 1
  fi
}

list_definitions() {
  { for definition in "${RUBY_BUILD_ROOT}/share/ruby-build/"*; do
      echo "${definition##*/}"
    done
  } | sort
}



unset VERBOSE
RUBY_BUILD_ROOT="$(abs_dirname "$0")/.."

case "$1" in
"-h" | "--help" )
  usage without_exiting
  { echo
    echo "  -v/--verbose     Verbose mode: print compilation status to stdout"
    echo "  --definitions    List all built-in definitions"
    echo
  } >&2
  exit 0
  ;;
"--definitions" )
  list_definitions
  exit 0
  ;;
"--version" )
  version
  exit 0
  ;;
"-v" | "--verbose" )
  VERBOSE=true
  shift
  ;;
esac


DEFINITION_PATH="$1"
if [ -z "$DEFINITION_PATH" ]; then
  usage
elif [ ! -e "$DEFINITION_PATH" ]; then
  BUILTIN_DEFINITION_PATH="${RUBY_BUILD_ROOT}/share/ruby-build/${DEFINITION_PATH}"
  if [ -e "$BUILTIN_DEFINITION_PATH" ]; then
    DEFINITION_PATH="$BUILTIN_DEFINITION_PATH"
  else
    echo "ruby-build: definition not found: ${DEFINITION_PATH}" >&2
    exit 1
  fi
fi

PREFIX_PATH="$2"
if [ -z "$PREFIX_PATH" ]; then
  usage
fi

if [ -z "$TMPDIR" ]; then
  TMP="/tmp"
else
  TMP="${TMPDIR%/}"
fi

SEED="$(date "+%Y%m%d%H%M%S").$$"
LOG_PATH="${TMP}/ruby-build.${SEED}.log"
TEMP_PATH="${TMP}/ruby-build.${SEED}"
RUBY_BIN="${PREFIX_PATH}/bin/ruby"
CWD="$(pwd)"

exec 4<> "$LOG_PATH" # open the log file at fd 4
if [ -n "$VERBOSE" ]; then
  tail -f "$LOG_PATH" &
  trap "kill 0" SIGINT SIGTERM EXIT
fi

export LDFLAGS="-L'${PREFIX_PATH}/lib' ${LDFLAGS}"
export CPPFLAGS="-I'${PREFIX_PATH}/include' ${CPPFLAGS}"

unset RUBYOPT
unset RUBYLIB

trap build_failed ERR
mkdir -p "$TEMP_PATH"
source "$DEFINITION_PATH"
rm -fr "$TEMP_PATH"
trap - ERR