configure

#!/usr/bin/env bash

PACKAGE_VERSION=0.3.0-alpha

function string#quote-arguments {
  ret=()
  local q=\' Q="'\''" special=$' \t\n\\`$!^'\"\'"#&|;()<>[*?]~{,}"
  while (($#)); do
    if [[ $1 != *["$special"]* ]]; then
      ret+=("$1")
    elif [[ $1 =~ ^([a-zA-Z0-9_]+=|--[a-zA-Z0-9][a-zA-Z0-9_-]*=)(.*)$ ]]; then
      ret+=("${BASH_REMATCH[1]}'${BASH_REMATCH[2]//$q/$Q}'")
    else
      ret+=("'${1//$q/$Q}'")
    fi
    shift
  done
}

function util/replace-if-dirty {
  local src=$1.part dst=$1
  if diff -q "$src" "$dst" >/dev/null; then
    rm -f "$src"
  else
    mv "$src" "$dst"
  fi
}

function check-lib {
  local prefix=$1 name=$2
  [[ -s $prefix/lib/lib$name.a || -s $prefix/lib/lib$name.so ]]
}

function readargs/option:with-jam1 {
  if check-lib "$1" jam; then
    libjam1_PREFIX=$1
  else
    echo "configure: jam1 not found at '$1'" >&2
    [[ :$2: == *:opt:* ]] || flags=E$flags
    return 1
  fi
}
function readargs/option:with-jam2 {
  if check-lib "$1" jam2; then
    libjam2_PREFIX=$1
  else
    echo "configure: jam2 not found at '$1'" >&2
    [[ :$2: == *:opt:* ]] || flags=E$flags
    return 1
  fi
}
function readargs/option:with-pythia8 {
  if check-lib "$1" pythia8; then
    pythia8_PREFIX=$1
  else
    echo "configure: pythia8 not found at '$1'" >&2
    [[ :$2: == *:opt:* ]] || flags=E$flags
    return 1
  fi
}
function readargs/option:help {
  printf '%s\n' \
         'usage: configure [OPTION|VAR=VAL]...' \
         '' \
         'OPTION' \
         '  --help            print this help' \
         '  --config          print the previous configure flags' \
         '' \
         '  --with-jam1=JAM1_PREFIX_DIR' \
         '                    specify the path of jam1 installation' \
         '  --with-jam2=JAM2_PREFIX_DIR' \
         '                    specify the path of jam2 installation' \
         '  --with-pythia8=Pythia8_PREFIX_DIR' \
         '                    specify the path of pythia8 installation' \
         '  --static-libjam1  statically link libjam1.a' \
         '  --static-libjam2  statically link libjam2.a' \
         '  --static-pythia8  statically link libpythia8.a' \
         '  --static          statically link all the above libaries' \
         ''
}
function readargs/option:config {
  if [[ -s config.mk ]]; then
    sed -n 's/^configure := //p' config.mk
    return 0
  else
    echo "./configure --config: configure has never been called." >&2
    return 1
  fi
}

## @fn readargs
##   @var[out] flags
##   @var[out] PREFIX
##   @var[out] libjam1_PREFIX
function readargs {
  opts=
  flags=
  libjam1_PREFIX=
  libjam2_PREFIX=
  pythia8_PREFIX=
  PREFIX=~/.opt/idt

  while (($#)); do
    local arg=$1; shift
    if [[ $flags != *R* ]]; then
      if local rex='^[[:alnum:]_]+='; [[ $arg =~ $rex ]]; then
        printf -v "${arg%%=*}" %s "${arg#*=}"
      elif [[ $arg == -* ]]; then
        case $arg in
        (--help)
          readargs/option:help
          flags=H$flags ;;
        (--config)
          readargs/option:config
          flags=H$flags ;;

        (--prefix=*) PREFIX=${arg#*=} ;;
        (--prefix)   PREFIX=$1; shift ;;
        (--with-jam1=*) readargs/option:with-jam1 "${arg#*=}" ;;
        (--with-jam1)   readargs/option:with-jam1 "$1"; shift ;;
        (--with-jam2=*) readargs/option:with-jam2 "${arg#*=}" ;;
        (--with-jam2)   readargs/option:with-jam2 "$1"; shift ;;
        (--with-pythia8=*) readargs/option:with-pythia8 "${arg#*=}" ;;
        (--with-pythia8)   readargs/option:with-pythia8 "$1"; shift ;;
        (--static | --static-pythia8 | --static-jam[12]) opts=$opts:${arg#--} ;;

        # old names of the option
        (--with-jam=*) readargs/option:with-jam1 "${arg#*=}" ;;
        (--with-jam)   readargs/option:with-jam1 "$1"; shift ;;

        (*)
          echo "configure: unknown option '$arg'" >&2
          flags=E$flags ;;
        esac
      else
        echo "configure: unrecognized argument '$arg'" >&2
        flags=E$flags
      fi
    fi
  done

  : "${PREFIX:-/usr}"
  [[ $flags != *E* ]]
}

function main {
  : "${CXX:=g++}"

  local flags opts libjam1_PREFIX libjam2_PREFIX pythia8_PREFIX
  readargs "$@" || return 1
  [[ $flags == *H* ]] && return 0

  # fall back to default locations
  [[ $libjam1_PREFIX ]] ||
    readargs/option:with-jam1 "$PREFIX" opt ||
    readargs/option:with-jam1 ~/opt/jam/1.820 opt ||
    readargs/option:with-jam1 ~/opt/jam-1.820 opt
  [[ $libjam2_PREFIX ]] ||
    readargs/option:with-jam2 "$PREFIX" opt ||
    readargs/option:with-jam2 ~/.opt/jam/dev jam2 opt
  [[ $pythia8_PREFIX ]] ||
    readargs/option:with-pythia8 "$PREFIX" opt ||
    readargs/option:with-pythia8 ~/.opt/pythia/8.315 opt

  # determine caps
  use_libjam1=
  use_libjam2=
  if [[ $libjam1_PREFIX ]]; then
    use_libjam1=yes
    libjam1_MXV=200000
  fi
  if [[ $libjam2_PREFIX && $pythia8_PREFIX ]]; then
    use_libjam2=yes
  elif [[ $libjam2_PREFIX ]]; then
    printf 'note: libpythia-8.315 is required for the JAM2 support but not found.\n' >&2
  fi

  local ret; string#quote-arguments "$@"
  local configure_command="./configure ${ret[*]}"

  echo ---------------------------------------
  {
    echo '# -*- mode: makefile-gmake -*-'
    echo
    {
      echo "configure := $configure_command"
      echo "PREFIX    := $PREFIX"
      echo "CXX       := $CXX"
      echo "CPPFLAGS  := $CPPFLAGS"
      echo "CXXFLAGS  := $CXXFLAGS"
      echo "LDFLAGS   := $LDFLAGS"
      echo "LIBS      := $LIBS"
      echo "use_libjam1 := $use_libjam1"
      echo "ifneq (\$(use_libjam1),)"
      echo "  libjam1_PREFIX := $libjam1_PREFIX"
      if [[ ( :$opts: == *:static:* || :$opts: == *:static-jam1:* ) && -s $libjam1_PREFIX/lib/libjam.a ]]; then
        echo "  libjam1_LIBS := $libjam1_PREFIX/lib/libjam.a"
      else
        echo "  libjam1_LIBS := -ljam"
      fi
      echo "  libjam1_MXV := $libjam1_MXV"
      echo "endif"
      echo "use_libjam2 := $use_libjam2"
      echo "ifneq (\$(use_libjam2),)"
      echo "  libjam2_PREFIX := $libjam2_PREFIX"
      if [[ ( :$opts: == *:static:* || :$opts: == *:static-jam2:* ) && -s $libjam2_PREFIX/lib/libjam2.a ]]; then
        echo "  libjam2_LIBS := $libjam2_PREFIX/lib/libjam2.a"
      else
        echo "  libjam2_LIBS := -ljam2"
      fi
      echo "  pythia8_PREFIX := $pythia8_PREFIX"
      if [[ ( :$opts: == *:static:* || :$opts: == *:static-pythia8:* ) && -s $pythia8_PREFIX/lib/libpythia8.a ]]; then
        echo "  pythia8_LIBS := $pythia8_PREFIX/lib/libpythia8.a"
      else
        echo "  pythia8_LIBS := -lpythia8"
      fi
      echo "endif"
    } | tee /dev/tty
  } > config.mk #.part && util/replace-if-dirty config.mk

  {
    echo "#ifndef CONFIG_HPP"
    echo "#define CONFIG_HPP"
    echo "#define PACKAGE_VERSION \"$PACKAGE_VERSION\""
    echo "#define PACKAGE_PREFIX  \"$PREFIX\""
    echo "#define PACKAGE_BUILD   \"$PWD\""
    if [[ $use_libjam1 ]]; then
      echo "#define USE_LIBJAM1 1"
      echo "#define CONFIG_JAM_MXV $libjam1_MXV"
    else
      echo "#undef USE_LIBJAM1"
    fi
    if [[ $use_libjam2 ]]; then
      echo "#define USE_LIBJAM2 1"
      echo "#define Pythia8_PREFIX \"$pythia8_PREFIX\""
    else
      echo "#undef USE_LIBJAM2"
    fi
    if [[ $use_libjam2 ]]; then
      echo "#define DEFAULT_JAM_VERSION 2"
    elif [[ $use_libjam1 ]]; then
      echo "#define DEFAULT_JAM_VERSION 1"
    else
      echo "#define DEFAULT_JAM_VERSION 0"
    fi
    echo 'namespace idt {'
    echo 'namespace runjam {'
    echo '  extern const char* package_hash;'
    echo '}'
    echo '}'
    echo "#endif"
  } > config.hpp.part
  util/replace-if-dirty config.hpp

  {
    echo '#include "config.hpp"'
    echo 'namespace idt {'
    echo 'namespace runjam {'
    echo "  const char* package_hash = \"$hash\";"
    echo '}'
    echo '}'
  } > config.cpp.part
  ./mktool.sh update-commit-hash config.cpp.part
  util/replace-if-dirty config.cpp

  echo ---------------------------------------
}

main "$@"