#!/bin/sh
# Convenience wrapper for easily viewing/setting options that
# the project's CMake scripts will recognize
set -e
command="$0 $*"

# check for `cmake` command
type cmake >/dev/null 2>&1 || {
    echo "\
This package requires CMake, please install it first, then you may
use this configure script to access CMake equivalent functionality.\
" >&2
    exit 1
}

usage="\
Usage: $0 [OPTION]... [VAR=VALUE]...

  Build Options:
    --builddir=DIR         place build files in directory [build]
    --build-type=TYPE      set CMake build type [RelWithDebInfo]:
                             - Debug: optimizations off, debug symbols + flags
                             - MinSizeRel: size optimizations, debugging off
                             - Release: optimizations on, debugging off
                             - RelWithDebInfo: optimizations on,
                                   debug symbols on, debug flags off
    --generator=GENERATOR  CMake generator to use (see cmake --help)

  Installation Directories:
    --prefix=PREFIX        installation directory [/usr/local/zeek]

  Optional Features:
    --enable-debug         compile in debugging mode (like --build-type=Debug)

  Required Packages in Non-Standard Locations:
    --with-flex=PATH       path to flex executable
    --with-bison=PATH      path to bison executable

  Influential Environment Variables (only on first invocation
  per build directory):
    CC                     C compiler command
    CFLAGS                 C compiler flags
    CXX                    C++ compiler command
    CXXFLAGS               C++ compiler flags
"

sourcedir="$(cd "$(dirname "$0")" && pwd)"

# Function to append a CMake cache entry definition to the
# CMakeCacheEntries variable.
#   $1 is the cache entry variable name
#   $2 is the cache entry variable type
#   $3 is the cache entry variable value
append_cache_entry() {
    CMakeCacheEntries="$CMakeCacheEntries -D $1:$2=$3"
}

# Function to remove a CMake cache entry definition from the
# CMakeCacheEntries variable
#   $1 is the cache entry variable name
remove_cache_entry() {
    CMakeCacheEntries="$CMakeCacheEntries -U $1"

    # Even with -U, cmake still warns by default if
    # added previously with -D.
    CMakeCacheEntries="$CMakeCacheEntries --no-warn-unused-cli"
}

# set defaults
builddir=build
prefix=/usr/local/zeek
CMakeCacheEntries=""
append_cache_entry CMAKE_INSTALL_PREFIX PATH $prefix
append_cache_entry ENABLE_DEBUG BOOL false

# parse arguments
while [ $# -ne 0 ]; do
    case "$1" in
        -*=*) optarg=$(echo "$1" | sed 's/[-_a-zA-Z0-9]*=//') ;;
        *) optarg= ;;
    esac

    case "$1" in
        --help | -h)
            echo "${usage}" 1>&2
            exit 1
            ;;
        --builddir=*)
            builddir=$optarg
            ;;
        --build-type=*)
            append_cache_entry CMAKE_BUILD_TYPE STRING $optarg

            if [ $(echo "$optarg" | tr [:upper:] [:lower:]) = "debug" ]; then
                append_cache_entry ENABLE_DEBUG BOOL true
            fi
            ;;
        --generator=*)
            CMakeGenerator="$optarg"
            ;;
        --prefix=*)
            prefix=$optarg
            append_cache_entry CMAKE_INSTALL_PREFIX PATH $optarg
            ;;
        --enable-debug)
            append_cache_entry ENABLE_DEBUG BOOL true
            ;;
        --with-flex=*)
            append_cache_entry FLEX_EXECUTABLE PATH $optarg
            ;;
        --with-bison=*)
            append_cache_entry BISON_EXECUTABLE PATH $optarg
            ;;
        *)
            echo "Invalid option '$1'.  Try $0 --help to see available options."
            exit 1
            ;;
    esac
    shift
done

if [ -d $builddir ]; then
    # If build directory exists, check if it has a CMake cache
    if [ -f $builddir/CMakeCache.txt ]; then
        # If the CMake cache exists, delete it so that this configuration
        # is not tainted by a previous one
        rm -f $builddir/CMakeCache.txt
    fi
else
    # Create build directory
    mkdir -p $builddir
fi

echo "Build Directory : $builddir"
echo "Source Directory: $sourcedir"
cd $builddir

if [ -n "$CMakeGenerator" ]; then
    cmake -G "$CMakeGenerator" $CMakeCacheEntries $sourcedir
else
    cmake $CMakeCacheEntries $sourcedir
fi

echo "# This is the command used to configure this build" >config.status
echo $command >>config.status
chmod u+x config.status