#!/bin/sh -e

trap 'rm -f config.mk' EXIT
trap 'rm -f config.mk; exit 1' INT

die() {
    printf '%s: %s\n' "${0##*/}" "$*" >&2
    exit 1
}

out() { printf '%s\n' "$@" ;}

usage() {
    out "usage: $0 [options]" \
        "Options:" \
        "  --prefix=dir         Set prefix directory" \
        "  --bindir=dir         Set directory where executables will be installed" \
        "  --manprefix=dir      Set directory where manual pages will be installed" \
        "  --with-fts=option    One of glibc, musl-fts, none, auto (default: auto)" \
        "  --with-system-zlib   Use system zlib"
    exit 1
}

prefix=/usr/local
# We don't want expansion
# shellcheck disable=2016
{
    bindir='$(PREFIX)/bin'
    manprefix='${PREFIX}/share/man'
}
fts=auto
host=

for arg; do
    case $arg in
        --help) usage ;;
        --prefix=*) prefix=${arg#*=} ;;
        --bindir=*) bindir=${arg#*=} ;;
        --manprefix=*) manprefix=${arg#*=} ;;
        --with-fts=*) fts=${arg#*=}  ;;
        --with-system-zlib) zlib=1   ;;
        -*) die "Unknown flag: '$arg'" ;;
        *=*) export "$arg";;
        *) die "Unknown option: '$arg'"
    esac
done

: ${CC:=cc}

printf 'checking system type... '
[ "$host" ] || host=$($CC -dumpmachine 2>/dev/null) || die "Could not determine host"
out "$host"

printf 'checking for libtls... '
tlslib=$(pkgconf --static --libs libtls) || die "No tls library found"
out "$tlslib"

case $host in
    *linux*) ;;
    *) die "Unsupported system: $host"
esac

cat <<EOF >config.mk
PREFIX    = $prefix
BINDIR    = $bindir
MANPREFIX = $manprefix

AR     ?= ${AR:-ar}
CC     ?= ${CC:-cc}
RANLIB ?= ${RANLIB:-ranlib}
RM     ?= rm -f
YACC   ?= ${YACC:-yacc}

TLSLIB = $tlslib
EOF

printf 'checking for zlib... '
if [ "$zlib" = 1 ]; then
    zlib=$(pkgconf --static --libs zlib)
    out "$zlib"
    out "ZLIB = $zlib" >> config.mk
else
    zlib=lib/libz/libz.a
    out "in source"
    out "ZLIB = $zlib" "MANDOCLIBS += $zlib" "GREPLIBS += $zlib" >>config.mk
fi

printf 'checking for fts... '
if [ "$fts" = auto ]; then
    if out "#include <fts.h>" | $CC -E - >/dev/null 2>&1; then
        fts=glibc
        pkgconf --exists musl-fts && fts=musl-fts
    else
        fts=none
    fi
fi

out "$fts"

case $fts in
    glibc) out "CFLAGS += -DHAVE_FTS" ;;
    musl-fts) out "CFLAGS += -DHAVE_FTS" "LIBFTS = -lfts" ;;
    none) out "LIBOBJ += lib/libc/gen/fts.o"
esac >>config.mk

printf "Checking if less supports '-T'... "
if echo | less -T test >/dev/null 2>&1; then
    out yes
    out "CFLAGS += -DHAVE_LESS_T" >>config.mk
else
    out no
fi

out "written config.mk" "Run 'make' to compile otools"
trap - EXIT INT