#!/usr/bin/env sh
#
# Configure script for impl
#

CONFIGURE_CMD_ARGS="${*}"

PACKAGE_VERSION="0.1.0"
PACKAGE_DATE="$(date +%Y-%m-%d)"
PACKAGE_STRING="impl $PACKAGE_VERSION"
PACKAGE_BUGREPORT="ethan@gweithio.com"
PACKAGE_URL="https://sixfourtwelve.com/repos/impl.git"

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}"
			return 0
		fi
	done
	printf " not found\n" >&2
	return 1
}

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

# Default values
PREFIX="/usr/local"
OPTIMISE="release"
CC=""
AR="ar"
RANLIB="ranlib"
RM="rm"
INSTALL="install"

# Parse arguments
while [ $# -gt 0 ]; do
	case "$1" in
		--prefix=*)
			PREFIX="${1#--prefix=}"
			;;
		--prefix)
			shift
			PREFIX="$1"
			;;
		--debug)
			OPTIMISE="debug"
			;;
		--release)
			OPTIMISE="release"
			;;
		--help)
			cat <<EOF
Configure script for impl

Options:
  --prefix=PREFIX        Installation prefix (default: /usr/local)
  --debug                Build with debug symbols, no optimization
  --release              Build with optimizations (default)
  --help                 Show this help message

Environment variables:
  CC                     C compiler
  AR                     Archiver
  RANLIB                 ranlib
  CFLAGS                 Additional C flags
  LDFLAGS                Additional linker flags
EOF
			exit 0
			;;
		*)
			die "Unknown option: $1"
			;;
	esac
	shift
done

# Find required tools
if [ -z "$CC" ]; then
	CC=$(find_program CC cc clang gcc) || die "No C compiler found"
fi

# Use basename only for better tool compatibility (e.g., bear)
CC=$(basename "$CC")

# Detect compiler type
if $CC --version 2>&1 | grep -i clang >/dev/null; then
	CCOM="clang"
elif $CC --version 2>&1 | grep -i gcc >/dev/null; then
	CCOM="gcc"
else
	CCOM="unknown"
fi

printf "Compiler: %s (%s)\n" "$CC" "$CCOM"

# Generate config.h
cat > config.h <<EOF_CONFIG
#ifndef CONFIG_H
#define CONFIG_H

#define PACKAGE_VERSION "$PACKAGE_VERSION"
#define PACKAGE_STRING "$PACKAGE_STRING"
#define PACKAGE_BUGREPORT "$PACKAGE_BUGREPORT"
#define PACKAGE_URL "$PACKAGE_URL"

#endif /* CONFIG_H */
EOF_CONFIG

# Determine source directory
SRCDIR="$(dirname "$0")"
SRCDIR="$(cd "$SRCDIR" && pwd)"

# Generate Makefile from Makefile.in
sed \
	-e "s|@PREFIX@|$PREFIX|g" \
	-e "s|@CC@|$CC|g" \
	-e "s|@CCOM@|$CCOM|g" \
	-e "s|@AR@|$AR|g" \
	-e "s|@RANLIB@|$RANLIB|g" \
	-e "s|@RM@|$RM|g" \
	-e "s|@INSTALL@|$INSTALL|g" \
	-e "s|@OPTIMISE@|$OPTIMISE|g" \
	-e "s|@VERSION@|$PACKAGE_VERSION|g" \
	-e "s|@SRCDIR@|$SRCDIR|g" \
	< "$SRCDIR/Makefile.in" > Makefile

echo "Configuration complete. Run 'make' to build."