#!/usr/bin/env sh
#
#
# NOTE: Before you start yelling, yes this is NOT a GNU auto* build
#       system. However, I have written this in a way that it
#       has as few changes as needed.
#
#       You still have all the features:
#
#       - Cross Compilation Support
#       - Support for various compilers and operating systems
#       - Out-of-tree builds
#       - DESTDIR/PREFIX install
#       - Test suite
#
#       PLEASE READ THE README / HACKING GUIDE FOR MORE INFORMATION.

CONFIGURE_CMD_ARGS="${*}"

PACKAGE_VERSION="2.10.0"
PACKAGE_DATE="31-Dec-2025"
PACKAGE_STRING="gcli $PACKAGE_VERSION"
PACKAGE_BUGREPORT="https://lists.sr.ht/~herrhotzenplotz/gcli-discuss"
PACKAGE_URL="https://sr.ht/~herrhotzenplotz/gcli"

find_program() {
	varname=$1
	shift

	printf "Checking for $varname ..." >&2
	for x in $*; do
		if command -v $x >/dev/null 2>&1 && [ -x $(command -v $x) ]; then
			binary="$(command -v $x)"
			printf " $binary\n" >&2
			echo "${binary}"
			exit 0
		fi
	done
	printf " not found\n" >&2
	exit 1

}

die() {
	printf "%s\n" "${*}"
	exit 1
}

tolower() {
	tr '[:upper:]' '[:lower:]'
}

check_compiler() {
	command -v "${1}" > /dev/null 2>&1 || die " '${1}' not found"
}

compiler_type() {
	if ${1} -v 2>&1 | grep clang > /dev/null; then
		echo "clang"
	elif ${1} -v 2>&1 | grep '^gcc' > /dev/null; then
		echo "gcc"
	elif ${1} -qversion 2>&1 | grep 'IBM XL C' >/dev/null; then
		echo "xlc"
	elif ${1} -V 2>&1 | grep 'Studio' > /dev/null; then
		echo "sunstudio"
	else
		echo "unknown"
	fi
}

normalise_compiler_target() {
	tolower | sed -e 's|x86_64|amd64|g' -e 's| ||g'
}

compiler_target() {
	ccom=$1
	cc=$2

	case $ccom in
		gcc|clang)
			$cc -v 2>&1 \
				| grep '^Target' \
				| cut -d: -f2
			;;
		xlc)
			# for xlc we can't easily get its target. instead we ask its
			# configured assembler for the target. Right now I assume it
			# is a GNU assembler. If this doesn't work for you please fix!
			# I don't have access to any equipment running anything else
			# and I will not beg IBM for giving me access.
			xlc_config=$($cc -v 2>&1 | grep XL_CONFIG | sed 's|.*XL_CONFIG=\([^:]*\):.*|\1|')
			[ -z "${xlc_config}" ] && die "xlc config file not detected"
			xlc_as=$(cat $xlc_config | grep -E 'as[\t ]+.*=[ ]+' | sed 1q | cut -d= -f2 | sed 's| ||g')
			[ -z "${xlc_as}" ] && die "failed to figure out assembler used by XL C"
			$xlc_as --version 2>&1 | grep 'GNU assembler' >/dev/null || die "Can only derive compiler target from GNU assembler, please submit fix for your assembler"
			$xlc_as --version 2>&1 | grep target | sed "s|.*\`\([^']*\)'.*|\1|"
			;;
		sunstudio)
			# Only tested on Solaris 10 ... if this messes up on Linux or SunOS
			# i86pc feel free to send a patch...
			if $cc -V 2>&1 | grep SunOS_sparc > /dev/null; then
				echo "sparc64-unknown-solaris"
			else
				echo "unknown-unknown-unknown"
			fi
			;;
		*)
			echo "unknown-unknown-unknown"
			;;
	esac | normalise_compiler_target
}

# args= pkgconfig-name variable-name is-mandatory
find_package() {
	printf "Checking for $1 ..." >&2
	if ! $PKG_CONFIG --exists $1; then
		if [ "${3}" = optional ]; then
			printf " not found\n"
			export ${2}_FOUND=0
			return
		else # $3 = required
			die "not found"
		fi
	fi

	# readline and possibly other dependencies in Debian (yikes)
	# return -D_XOPEN_SOURCE which breaks builds. Rip it out -
	# we know what we're doing... ha!
	export ${2}_CFLAGS="$($PKG_CONFIG --cflags $1 | sed 's|-D_XOPEN_SOURCE=[[:digit:]]*||g')"
	export ${2}_LIBS="$($PKG_CONFIG --libs $1)"
	export ${2}_FOUND=1
	export ${2}_VERSION="$($PKG_CONFIG --modversion $1)"

	printf " found\n" >&2
}

usage() {
	cat >&2 <<EOF
usage: ./configure [options]

Configure build directory of gcli.

OPTIONS:
    --prefix=PREFIX         Set installation prefix to PREFIX [DEFAULT: /usr/local]
    --disable-libedit       Disable use of libedit for interactive editing [DEFAULT: autodetect]
    --disable-libreadline   Disable use of libreadline for interactive editing [DEFAULT: autodetect]
    --disable-liblowdown    Disable use of liblowdown for markdown rendering [DEFAULT: autodetect]
    --disable-librt         Forcefully disable linking librt [DEFAULT: no, except on Darwin]
    --enable-maintainer     Enable Maintainer Mode [DEFAULT: no]
                            You only want this if you're working on the gcli source code.
                            In this case certain build targets get enabled that only work
                            when the source directory is writable.
                            Do NOT use this flag together with --release or when packaging
                            gcli.
    --enable-sanitisers     Enable compiler-specific sanitisers
    --debug                 Compile without optimisations, generate code with
                            debug information and enable additional compiler-specific
                            warnings and portability checks.
    --release               Optimise for release
    --help                  Print this help

ENVIRONMENT:
    CC                      Host system compiler to use [DEFAULT: cc]
    CC_FOR_BUILD            Build system compiler [DEFAULT: \$CC]
    CFLAGS                  Host system C compiler flags
    CFLAGS_FOR_BUILD        Build system compiler flags
    CPPFLAGS                C Preprocessor flags for host system compiler
    CPPFLAGS_FOR_BUILD      C Preprocessor flags for build system compiler
    LDFLAGS                 Host system linker flags
    LDFLAGS_FOR_BUILD       Build system linker flags
    PKG_CONFIG              pkg-config to use [DEFAULT: autodetect]
    AR                      Archiver to use [DEFAULT: autodetect]
    RANLIB                  Ranlib to use [DEFAULT: autodetect]
    RM                      rm to use [DEFAULT: autodetect]
    CCACHE                  Path to ccache [DEFAULT: autodetect]
    PERL                    Path to perl for test suite [DEFAULT: autodetect]
    INSTALL                 Path to install [DEFAULT: autodetect]
    EXEEXT                  File extension of executable files for the host system [DEFAULT: '', '.exe' on Windows]
    OBJEXT                  File extension of object files for the host system [DEFAULT: '.o', '.obj' on Windows]
    LIBEXT                  File extension of static libraries for the host system [DEFAULT: '.a', '.lib' on Windows]
    EXEEXT_FOR_BUILD        File extension of executable files for the build system [DEFAULT: '', '.exe' on Windows]
    OBJEXT_FOR_BUILD        File extension of object files for the build system [DEFAULT: '.o', '.obj' on Windows]
    LIBEXT_FOR_BUILD        File extension of static libraries for the build system [DEFAULT: '.a', '.lib' on Windows]
EOF
	exit 1
}

# Install options
#
PREFIX=/usr/local
OPTIMISE=
ENABLE_LIBEDIT=1
ENABLE_LIBREADLINE=1
ENABLE_LIBLOWDOWN=1
ENABLE_LIBRT=1
ENABLE_MAINTAINER=${ENABLE_MAINTAINER:-0}
ENABLE_TESTS=1
ENABLE_SANITISERS=${ENABLE_SANITISERS:-0}

# Parse flags
while [ $# -gt 0 ]; do
	case "$1" in
		--prefix=*)
			PREFIX=${1##--prefix=}
			shift
			;;
		--prefix)
			PREFIX=${2}
			shift; shift
			;;
		--enable-libedit|--enable-libreadline|--enable-liblowdown)
			echo "configure: warning: $1 is deprecated and ignored" >&2
			shift
			;;
		--disable-libedit)
			ENABLE_LIBEDIT=0
			shift
			;;
		--disable-libreadline)
			ENABLE_LIBREADLINE=0
			shift
			;;
		--disable-librt)
			ENABLE_LIBRT=0
			shift
			;;
		--disable-liblowdown)
			ENABLE_LIBLOWDOWN=0
			shift
			;;
		--enable-maintainer)
			ENABLE_MAINTAINER=1
			shift
			;;
		--disable-tests)
			ENABLE_TESTS=0
			shift
			;;
		--enable-sanitisers)
			ENABLE_SANITISERS=1
			shift
			;;
		--debug)
			OPTIMISE=debug
			shift
			;;
		--release)
			OPTIMISE=release
			shift
			;;
		--help)
			usage
			;;
		*)
			die "error: unknown flag: $1"
			;;
	esac
done

REALPATH=${REALPATH:-$(find_program realpath realpath grealpath)}
[ $? -eq 0 ] || die "error: need realpath" # exit code of find_program()

rel_srcdir="$(dirname ${0})"
srcdir="$(${REALPATH} ${rel_srcdir})"

###############################################################
# COMPILERS
###############################################################

# Host Compiler
printf "Checking host compiler ..."
CC=${CC:-cc}
check_compiler "${CC}"
printf " $CC\n"

# Detect the compiler type and enable dependency tracking
printf "Checking host compiler type ..."
CCOM=$(compiler_type "${CC}")
printf " $CCOM\n"

printf "Checking host compiler target ..."
HOST=$(compiler_target $CCOM "$CC $CFLAGS $CPPFLAGS")
printf " $HOST\n"

# Build compiler
CC_FOR_BUILD=${CC_FOR_BUILD:-${CC}}

printf "Checking for build compiler..."
check_compiler "${CC_FOR_BUILD}"
printf " ${CC_FOR_BUILD}\n"

printf "Checking build compiler type..."
CCOM_FOR_BUILD=$(compiler_type "${CC_FOR_BUILD}")
printf " ${CCOM_FOR_BUILD}\n"

printf "Checking build compiler target ..."
BUILD=$(compiler_target $CCOM_FOR_BUILD $CC_FOR_BUILD)
printf " $BUILD\n"

############################################################################
# LIBRARIES
############################################################################
PKG_CONFIG=${PKG_CONFIG:-$(find_program pkg-config pkg-config pkgconf)}
[ $? -eq 0 ] || die "error: need pkg-config or pkgconf"

find_package libcurl LIBCURL required
find_package libcrypto LIBCRYPTO required

# Look for libedit if not disabled
if [ $ENABLE_LIBEDIT -eq 1 ]; then
	find_package libedit LIBEDIT optional
else
	LIBEDIT_FOUND=0
fi

# Now only look for readline if libedit hasn't been found/enabled
# and readline support hasn't been disabled.
if [ $LIBEDIT_FOUND -eq 1 ]; then
	LIBREADLINE_FOUND=0
elif [ $ENABLE_LIBREADLINE -eq 1 ]; then
	find_package readline LIBREADLINE optional
else
	LIBREADLINE_FOUND=0
fi

# Lowdown
if [ $ENABLE_LIBLOWDOWN -eq 1 ]; then
	find_package lowdown LIBLOWDOWN optional

	# Workaround for breaking API changes and header without versions:
	#
	# See https://github.com/kristapsdz/lowdown/issues/148
	LIBLOWDOWN_MAJOR=$(echo $LIBLOWDOWN_VERSION | cut -d. -f1)
	LIBLOWDOWN_MINOR=$(echo $LIBLOWDOWN_VERSION | cut -d. -f2)
else
	LIBLOWDOWN_FOUND=0
fi

# If there is no system-provided pdjson, use the vendored one
find_package pdjson PDJSON optional

# On Darwin the POSIX Real-Time extensions are in libc. We must not
# link against librt because it doesn't exist.
if [ $ENABLE_LIBRT -eq 1 ]; then
	printf "Checking whether host is Darwin for -lrt..."
	case "${HOST}" in
		*-apple-darwin*)
			printf " yes, won't link -lrt\n"
			ENABLE_LIBRT=0
			;;
		*)
			printf " no\n"
			;;
	esac
fi

###################################################################
# File extensions for operating systems
#
# LIBEXT refers to static libraries.
guess_extension() {
	# Executables
	if [ "$1" = EXE ]; then
		case "${2}" in
		*mingw*|*cygwin*|*winnt*) echo ".exe" ;;
		*)                        echo "" ;;
		esac

	# Objects
	elif [ "$1" = OBJ ]; then
		case "${2}" in
		*mingw*|*cygwin*|*winnt*) echo ".obj" ;;
		*)                        echo ".o" ;;
		esac

	# Static Libraries
	elif [ "$1" = LIB ]; then
		case "${2}" in
		*mingw*|*cygwin*|*winnt*) echo ".lib" ;;
		*)                        echo ".a" ;;
		esac

	else
		die "internal configure error"
	fi
}

EXEEXT=${EXEEXT:-$(guess_extension EXE $HOST)} || die "error: failed to guess executable extension for $HOST"
OBJEXT=${OBJEXT:-$(guess_extension OBJ $HOST)} || die "error: failed to guess object extension for $HOST"
LIBEXT=${LIBEXT:-$(guess_extension LIB $HOST)} || die "error: failed to guess static library extension for $HOST"

EXEEXT_FOR_BUILD=${EXEEXT_FOR_BUILD:-$(guess_extension EXE $BUILD)} || die "error: failed to guess executable extension for $BUILD"
OBJEXT_FOR_BUILD=${OBJEXT_FOR_BUILD:-$(guess_extension OBJ $BUILD)} || die "error: failed to guess object extension for $BUILD"
LIBEXT_FOR_BUILD=${LIBEXT_FOR_BUILD:-$(guess_extension LIB $BUILD)} || die "error: failed to guess static library extension for $BUILD"

###################################################################
# TESTS and other programs
###################################################################
AR=${AR:-ar}
RANLIB=${RANLIB:-ranlib}
RM=${RM:-rm}
CCACHE=${CCACHE:-$(find_program ccache ccache)}
INSTALL=${INSTALL:-$(find_program install install ginstall)}
[ $? -eq 0 ] || die "error: need install program"
SHELL=${SHELL:-$(find_program sh sh zsh bash)}

# If maintainer mode is enabled, we need lowdown(1)
if [ ${ENABLE_MAINTAINER} -eq 1 ]; then
	LOWDOWN=${LOWDOWN:-$(find_program lowdown lowdown)}
	[ $? -eq 0 ] || die "error: couldn't find lowdown which is required in maintainer mode"
fi

if [ ${ENABLE_TESTS} -eq 1 ]; then
	PERL=${PERL:-$(find_program perl perl perl5)}
	if ! [ $? -eq 0 ]; then
		ENABLE_TESTS=0
		echo "configure: warning: tests are disabled because perl couldn't be found" >&2
	fi
fi

###################################################################
# Configure Makefile
###################################################################
#
# FIXME: this escapes the source directory in case it contains
#        spaces. however, both GNU and BSD make are incapable of
#        handling hese situations in combination with VPATH. On
#        NetBSD we get a bug where it hard-splits the path on spaces
#        in a prerequisite no matter whether it is escaped or not.
ESC_SRCDIR="$(echo ${srcdir} | sed -e 's| |\\\\ |g')"

sed \
	-e "s|@SRCDIR@|${ESC_SRCDIR}|g" \
	-e "s|@OPTIMISE@|$OPTIMISE|g" \
	-e "s|@LIBCURL_CFLAGS@|$LIBCURL_CFLAGS|g" \
	-e "s|@LIBCURL_LIBS@|$LIBCURL_LIBS|g" \
	-e "s|@LIBCRYPTO_CFLAGS@|$LIBCRYPTO_CFLAGS|g" \
	-e "s|@LIBCRYPTO_LIBS@|$LIBCRYPTO_LIBS|g" \
	-e "s|@LIBEDIT_FOUND@|$LIBEDIT_FOUND|g" \
	-e "s|@LIBEDIT_CFLAGS@|$LIBEDIT_CFLAGS|g" \
	-e "s|@LIBEDIT_LIBS@|$LIBEDIT_LIBS|g" \
	-e "s|@LIBREADLINE_FOUND@|$LIBREADLINE_FOUND|g" \
	-e "s|@LIBREADLINE_CFLAGS@|$LIBREADLINE_CFLAGS|g" \
	-e "s|@LIBREADLINE_LIBS@|$LIBREADLINE_LIBS|g" \
	-e "s|@LIBLOWDOWN_FOUND@|$LIBLOWDOWN_FOUND|g" \
	-e "s|@LIBLOWDOWN_CFLAGS@|$LIBLOWDOWN_CFLAGS|g" \
	-e "s|@LIBLOWDOWN_LIBS@|$LIBLOWDOWN_LIBS|g" \
	-e "s|@LIBLOWDOWN_MAJOR@|$LIBLOWDOWN_MAJOR|g" \
	-e "s|@LIBLOWDOWN_MINOR@|$LIBLOWDOWN_MINOR|g" \
	-e "s|@PDJSON_FOUND@|$PDJSON_FOUND|g" \
	-e "s|@PDJSON_CFLAGS@|$PDJSON_CFLAGS|g" \
	-e "s|@PDJSON_LIBS@|$PDJSON_LIBS|g" \
	-e "s|@ENABLE_LIBRT@|$ENABLE_LIBRT|g" \
	-e "s|@CONFIGURE_CMD_ARGS@|$CONFIGURE_CMD_ARGS|g" \
	-e "s|@CC@|$CC|g" \
	-e "s|@CCOM@|$CCOM|g" \
	-e "s|@ENV_CFLAGS@|$CFLAGS|g" \
	-e "s|@ENV_LDFLAGS@|$LDFLAGS|g" \
	-e "s|@ENV_LDFLAGS_FOR_BUILD@|$LDFLAGS_FOR_BUILD|g" \
	-e "s|@ENV_CPPFLAGS@|$CPPFLAGS|g" \
	-e "s|@CC_FOR_BUILD@|$CC_FOR_BUILD|g" \
	-e "s|@CCOM_FOR_BUILD@|$CCOM_FOR_BUILD|g" \
	-e "s|@ENV_CFLAGS_FOR_BUILD@|$CFLAGS_FOR_BUILD|g" \
	-e "s|@ENV_CPPFLAGS_FOR_BUILD@|$CPPFLAGS_FOR_BUILD|g" \
	-e "s|@ENV_PKG_CONFIG@|$PKG_CONFIG|g" \
	-e "s|@ENV_PKG_CONFIG_PATH@|$PKG_CONFIG_PATH|g" \
	-e "s|@ENV_PKG_CONFIG_LIBDIR@|$PKG_CONFIG_LIBDIR|g" \
	-e "s|@ENV_PKG_CONFIG_SYSROOT_DIR@|$PKG_CONFIG_SYSROOT_DIR|g" \
	-e "s|@AR@|$AR|g" \
	-e "s|@CCACHE@|$CCACHE|g" \
	-e "s|@RANLIB@|$RANLIB|g" \
	-e "s|@RM@|$RM|g" \
	-e "s|@PERL@|$PERL|g" \
	-e "s|@INSTALL@|$INSTALL|g" \
	-e "s|@SHELL@|$SHELL|g" \
	-e "s|@PREFIX@|$PREFIX|g" \
	-e "s|@PACKAGE_STRING@|$PACKAGE_STRING|g" \
	-e "s|@PACKAGE_DATE@|$PACKAGE_DATE|g" \
	-e "s|@PACKAGE_BUGREPORT@|$PACKAGE_BUGREPORT|g" \
	-e "s|@PACKAGE_URL@|$PACKAGE_URL|g" \
	-e "s|@PACKAGE_VERSION@|$PACKAGE_VERSION|g" \
	-e "s|@EXEEXT@|$EXEEXT|g" \
	-e "s|@OBJEXT@|$OBJEXT|g" \
	-e "s|@LIBEXT@|$LIBEXT|g" \
	-e "s|@EXEEXT_FOR_BUILD@|$EXEEXT_FOR_BUILD|g" \
	-e "s|@OBJEXT_FOR_BUILD@|$OBJEXT_FOR_BUILD|g" \
	-e "s|@LIBEXT_FOR_BUILD@|$LIBEXT_FOR_BUILD|g" \
	-e "s|@ENABLE_MAINTAINER@|$ENABLE_MAINTAINER|g" \
	-e "s|@ENABLE_TESTS@|$ENABLE_TESTS|g" \
	-e "s|@ENABLE_SANITISERS@|$ENABLE_SANITISERS|g" \
	-e "s|@LOWDOWN@|$LOWDOWN|g" \
	< "${srcdir}/Makefile.in" > Makefile

echo "Writing config.h"
cat > config.h <<EOF
#define PACKAGE_STRING "$PACKAGE_STRING"
#define PACKAGE_URL "$PACKAGE_URL"
#define PACKAGE_VERSION "$PACKAGE_VERSION"
#define PACKAGE_BUGREPORT "$PACKAGE_BUGREPORT"
#define PACKAGE_DATE "$PACKAGE_DATE"
#define HOSTOS "$HOST"
EOF

echo "Configuration summary for ${PACKAGE_STRING}:"
echo ""
echo "    Build system type: ${BUILD}"
echo "     Host system type: ${HOST}"
echo "         optimise for: ${OPTIMISE:-none}"
echo " Executable extension: Host: '${EXEEXT}', Build: '${EXEEXT_FOR_BUILD}'"
echo "     Object extension: Host: '${OBJEXT}', Build: '${OBJEXT_FOR_BUILD}'"
echo "    Library extension: Host: '${LIBEXT}', Build: '${LIBEXT_FOR_BUILD}'"
echo "                   CC: ${CC}"
echo "         CC_FOR_BUILD: ${CC_FOR_BUILD}"
echo "               CFLAGS: ${CFLAGS}"
echo "     CFLAGS_FOR_BUILD: ${CFLAGS_FOR_BUILD}"
echo "              LDFLAGS: ${LDFLAGS}"
echo "    LDFLAGS_FOR_BUILD: ${LDFLAGS_FOR_BUILD}"
echo "       LIBCURL_CFLAGS: ${LIBCURL_CFLAGS}"
echo "         LIBCURL_LIBS: ${LIBCURL_LIBS}"
if [ $LIBEDIT_FOUND -eq 1 ]; then
echo " Using libedit:"
echo "       LIBEDIT_CFLAGS: ${LIBEDIT_CFLAGS}"
echo "         LIBEDIT_LIBS: ${LIBEDIT_LIBS}"
elif [ $LIBREADLINE_FOUND -eq 1 ]; then
echo " Using libreadline:"
echo "   LIBREADLINE_CFLAGS: ${LIBREADLINE_CFLAGS}"
echo "     LIBREADLINE_LIBS: ${LIBREADLINE_LIBS}"
fi
if [ $LIBLOWDOWN_FOUND -eq 1 ]; then
echo " Using lowdown ${LIBLOWDOWN_VERSION}:"
echo "    LIBLOWDOWN_CFLAGS: ${LIBLOWDOWN_CFLAGS}"
echo "      LIBLOWDOWN_LIBS: ${LIBLOWDOWN_LIBS}"
fi
if [ $PDJSON_FOUND -eq 1 ]; then
echo " Using pdjson:"
echo "        PDJSON_CFLAGS: ${PDJSON_CFLAGS}"
echo "          PDJSON_LIBS: ${PDJSON_LIBS}"
else
echo ""
echo "     WARNING: pdjson not found, using vendored version."
echo "              You may wish to install a system version instead."
fi
if [ $ENABLE_LIBRT -eq 0 ]; then
echo " Not linking -lrt because it was disabled"
fi
if [ $ENABLE_MAINTAINER -eq 1 ]; then
echo ""
echo "     WARNING: Maintainer mode is enabled!"
fi
if [ $ENABLE_MAINTAINER -eq 1 ] && [ "${OPTIMISE}" = "release" ]; then
echo ""
echo "     WARNING: --enable-maintainer and --release specified together."
echo "              You probably don't want this for packaging."
echo "              Drop --enable-maintainer!"
fi
echo ""
echo "Configuration done. You may now run make."
echo "For more information about available build targets, run 'make help'."
echo ""

# vim: ft=sh
