#!/bin/sh
set -eu
cd -- "$(dirname -- "$0")"
self=./$(basename -- "$0")
. ../build_util.sh

# Get configuration from the environment
CC=${CC:-c99}
CFLAGS=${CFLAGS:-}
CPPFLAGS=${CPPFLAGS:-}
append_cppflag -D_DEFAULT_SOURCE
LDFLAGS=${LDFLAGS:-}
LDLIBS=
JOBS=${JOBS:-1}
LTO=${LTO:-false}
PGO=${PGO:-false}
STATIC=${STATIC:-false}
NATIVE=${NATIVE:-false}
CONFIG=${CONFIG:-release}
PREFIX=$(preadlinkf "${DESTDIR+${DESTDIR%/}}${PREFIX:-/usr/local}")

typecheck bool LTO PGO STATIC NATIVE
typecheck uint JOBS

# Target specific values
STD=c99
BIN=prog-c
[ -f ../VERSION ] && version=$(cat ../VERSION) || version=$(git_version ..)
append_cppflag \
	-DPROG_NAME="$(dquote "$BIN" 2)" \
	-DPROG_VERSION="$(dquote "$version" 2)"
LDLIBS='-pthread -lm'
USE_FEATURE1=${USE_FEATURE1:-true}
USE_FEATURE2=${USE_FEATURE2:-false}


# Prepare the source list (must be done before any cclean call)
SRC=$(printf '%s\n' *.c)

# gperf files detection
gperf=$(listfiles . -name '*.gperf' | sed 's#^\./##; s#\.gperf$#.c#')
if [ "$gperf" ]
then
	! command -v gperf >/dev/null && die "gperf: command not found"
	SRC=$SRC$gperf
fi

# lex files detection
lex=$(listfiles . -name '*.lex' | sed 's#^\./##; s#\.lex$#.c#')
if [ "$lex" ]
then
	SRC=$SRC$lex
fi

# Remove duplicates inserted by gperf/lex detection
SRC=$(pecho "$SRC" | awk '!seen[$0]++')

# Conditional features processing
SRC=$(pecho "$SRC" | grep -Evx '(feature1|feature2)\.c')

if "$USE_FEATURE1"
then
	append_cppflag -DUSE_FEATURE1
	# LDLIBS="$LDLIBS -lfeat1"
	appendnl SRC feature1.c
fi
if "$USE_FEATURE2"
then
	append_cppflag -DUSE_FEATURE2
	# LDLIBS="$LDLIBS -lfeat2"
	appendnl SRC feature2.c
fi

# Argument parsing
if "$PGO"
then
	[ $# -eq 0 ] && die "PGO is useless without a command to run"
else
	if [ $# -eq 1 ]
	then
		case "$(tolower "$1")" in
			clean)
				cclean
				;;
			install)
				pb_install -m 755 "$PREFIX"/bin/ "$BIN"
				pb_install -m 644 "$PREFIX"/share/doc/"$PROJECT"/README_"$BIN" README
				;;
			uninstall)
				uninstall \
					"$PREFIX/bin/$BIN" \
					"$PREFIX"/share/doc/"$PROJECT"/README_"$BIN"
				;;
			help)
				pb_usage 0
				;;
			*)
				die "$1: unknown action"
				;;
		esac
		exit
	elif [ $# -gt 1 ]
	then
		pb_usage 1
	fi
fi

# Detect compiler vendor
case "$(tolower "$CC")" in
	*gcc*)
		cctype=gcc
		;;
	*clang*)
		cctype=clang
		;;
	*)
		cctype=c99
		[ "$STD" != c99 ] && die "$STD: c99 only support the c99 standard"
		;;
esac

# Apply PGO with workload specified by "$@"
if "$PGO"
then
	xtest_cflag -fprofile-generate
	case "$cctype" in
		gcc)
			PGO=false CFLAGS="$CFLAGS -fprofile-generate" \
				LDFLAGS="$LDFLAGS -fprofile-generate" "$self"
			(
				cd - >/dev/null
				"$@"
			)
			cclean
			append_ldflag -fprofile-use
			append_cflag -fprofile-use
			;;
		clang)
			PGO=false CFLAGS="$CFLAGS -fprofile-generate=$(dquote "$PWD")" \
				LDFLAGS="$LDFLAGS -fprofile-generate=$(dquote "$PWD")" "$self"
			(
				cd - >/dev/null
				"$@"
			)
			cclean
			llvm-profdata merge -output=default.profdata default_*.profraw
			append_ldflag -fprofile-use="$PWD"
			append_cflag -fprofile-use="$PWD"
			;;
		*)
			die "Unknown PGO supporting compiler"
			;;
	esac
fi

# Process CONFIG
case "$(tolower "$CONFIG")" in
	debug)
		test_append_cflag -g3 || append_cflag -g
		test_append_cflag -Og || append_cflag -O0
		test_append_cflag -fsanitize=address &&
			append_ldflag -fsanitize=address
		test_append_cflag -fsanitize=undefined &&
			append_ldflag -fsanitize=undefined
		;;
	release)
		test_append_cflag -O3 || append_cflag -O1
		append_cppflag -DNDEBUG
		append_ldflag -s
		test_append_ldflag -Wl,-O1
		;;
	*)
		die "$CONFIG: unknown config"
		;;
esac

# Diverse CFLAG/LDFLAG additions
"$NATIVE" && xtest_append_cflag -march=native
"$STATIC" && xtest_append_ldflag -static
[ "$CC" != c99 ] && xtest_append_cflag -std="$STD"
test_append_cflag -pedantic -Wall -Wextra # -Wconversion
test_append_ldflag -Wl,-z,defs
[ "${LD:-}" ] && test_append_ldflag -fuse-ld="${LD#ld.}"

# Apply LTO
if "$LTO"
then
	xtest_cflag -flto
	case "$cctype" in
		gcc)
			append_ldflag -flto="$JOBS" "$CFLAGS"
			append_cflag -flto -fno-fat-lto-objects
			;;
		clang)
			append_cflag -flto=thin
			append_ldflag "$CFLAGS"
			;;
		*)
			die "Unknown LTO supporting compiler"
			;;
	esac
fi

pb_make