#!/bin/sh

msg() {
    echo "configure: $1"
}

err() {
    echo "configure: error: $1"
    exit 1
}


need_cmd() {
    if which $1 >/dev/null 2>&1
    then msg "found $1"
    else err "need $1"
    fi
}

make_dir() {
    if [ ! -d $1 ]
    then
        msg "mkdir -p $1"
        mkdir -p $1
    fi
}

copy() {
    msg "cp $1 $2"
    cp $1 $2
}

putvar() {
    local T
    eval T=\$$1
    eval TLEN=\${#$1}
    if [ $TLEN -gt 35 ]
    then
        printf "configure: %-20s := %.35s ...\n" $1 "$T"
    else
        printf "configure: %-20s := %s\n" $1 "$T"
    fi
    printf "%-20s := %s\n" $1 "$T" >>config.mk
}

probe() {
    local V=$1
    local P=$2
    local T
    T=$(which $P 2>&1)
    if [ $? -ne 0 ]
    then
        T=""
    fi
    eval $V=\$T
    putvar $V
}

probe_need() {
    local V=$1
    local P=$2
    probe $V $P
    eval VV=\$$V
    if [ -z "$VV" ]
    then
        err "required program '$P' not found"
    fi
}

msg "looking for configure programs"
need_cmd mkdir
need_cmd printf
need_cmd cut
need_cmd grep
need_cmd xargs
need_cmd cp
need_cmd find
need_cmd uname
need_cmd date
need_cmd tr

msg "inspecting environment"

CFG_OSTYPE=$(uname -s)
CFG_CPUTYPE=$(uname -m)

CFG_SELF=$(echo $0 | tr '\' '/')
CFG_SRC_DIR=${CFG_SELF%${CFG_SELF##*/}}
CFG_BUILD_DIR=$(echo $PWD | tr '\' '/')

msg "recreating config.mk"
echo '' >config.mk

msg "making directories"
for i in \
    doc \
    boot/fe boot/me boot/be boot/driver boot/util \
    rt rt/isaac rt/bigint rt/sync rt/test \
    rustllvm \
    stage0 stage1 stage2 \
    test/run-pass test/run-fail test/compile-fail \
    test/bench/99-bottles test/bench/shootout
do
    make_dir $i
done

putvar CFG_SRC_DIR
putvar CFG_BUILD_DIR
putvar CFG_OSTYPE
putvar CFG_CPUTYPE

msg "looking for build programs"
probe_need CFG_GCC          gcc
probe_need CFG_GIT          git
probe_need CFG_OCAMLC       ocamlc
probe_need CFG_PERL         perl
probe_need CFG_PYTHON       python

probe CFG_LLVM_CONFIG      llvm-config
probe CFG_VALGRIND         valgrind
probe CFG_OCAMLOPT         ocamlopt
probe CFG_OCAMLC_OPT       ocamlc.opt
probe CFG_OCAMLOPT_OPT     ocamlopt.opt
probe CFG_FLEXLINK         flexlink
probe CFG_MAKEINFO         makeinfo
probe CFG_TEXI2PDF         texi2pdf
probe CFG_TEX              tex

if [ ! -z "$CFG_LLVM_ROOT" ]
then
    CFG_LLVM_INCDIR="$CFG_LLVM_ROOT/include"
    CFG_LLVM_BINDIR="$CFG_LLVM_ROOT/bin"
    CFG_LLVM_LIBDIR="$CFG_LLVM_ROOT/lib"
    CFG_LLVM_CXXFLAGS="-I$CFG_LLVM_INCDIR"
    CFG_LLVM_LDFLAGS=""
    CFG_LLVM_LIBS=$(find "$CFG_LLVM_LIBDIR" \
                    -name '*.lib' \
                    -exec echo '\"{}\"' ';' \
                    | xargs echo)
    CFG_LLVM_VERSION=$("$CFG_LLVM_BINDIR/llc" \
                       --version \
                       | grep version \
                       | cut -d ' ' -f 5-)
elif [ ! -z "$CFG_LLVM_CONFIG" ]
then
    CFG_LLVM_VERSION=$(llvm-config --version)
    CFG_LLVM_INCDIR=$(llvm-config --includedir)
    CFG_LLVM_BINDIR=$(llvm-config --bindir)
    CFG_LLVM_LIBDIR=$(llvm-config --libdir)
    CFG_LLVM_CXXFLAGS=$(llvm-config --cxxflags)
    CFG_LLVM_LDFLAGS=$(llvm-config --ldflags)
    CFG_LLVM_LIBS=$(llvm-config --libs)
else
    err "either the \"CFG_LLVM_ROOT\" environment variable must be set, or a \
\"llvm-config\" script must be present"
fi

case $CFG_LLVM_VERSION in
    (3.0svn | 3.0)
    msg "found ok version of LLVM: $CFG_LLVM_VERSION"
    ;;
    (*)
    err "bad LLVM version: $CFG_LLVM_VERSION, need >=3.0svn"
    ;;
esac

putvar CFG_LLVM_INCDIR
putvar CFG_LLVM_BINDIR
putvar CFG_LLVM_LIBDIR
putvar CFG_LLVM_CXXFLAGS
putvar CFG_LLVM_LDFLAGS
putvar CFG_LLVM_LIBS

# Munge any paths that appear in config.mk back to posix-y
perl -i.bak -p -e 's@ ([a-zA-Z]):[/\\]@ /\1/@go;' \
               -e 's@\\@/@go;' config.mk
rm -f config.mk.bak

copy ${CFG_SRC_DIR}Makefile.in ./Makefile

echo "configure: complete"