#!/bin/sh

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

step_msg() {
    msg
    msg "$1"
    msg
}

warn() {
    echo "configure: WARNING: $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
}

valopt() {
    local OP=$1
    local DEFAULT=$2
    shift
    shift
    local DOC="$*"
    if [ $HELP -eq 0 ]
    then
        local UOP=$(echo $OP | tr 'a-z-' 'A-Z_')
        local V="CFG_${UOP}"
        eval $V="$DEFAULT"
        for arg in $CFG_CONFIGURE_ARGS
        do
            if echo "$arg" | grep -q -- "--$OP="
            then
                val=$(echo "$arg" | cut -f2 -d=)
                eval $V=$val
            fi
        done
        putvar $V
    else
        if [ -z "$DEFAULT" ]
        then
            DEFAULT="<none>"
        fi
        OP="${OP}=[${DEFAULT}]"
        printf "    --%-30s %s\n" "$OP" "$DOC"
    fi
}

opt() {
    local OP=$1
    local DEFAULT=$2
    shift
    shift
    local DOC="$*"
    local FLAG=""

    if [ $DEFAULT -eq 0 ]
    then
        FLAG="enable"
    else
        FLAG="disable"
        DOC="don't $DOC"
    fi

    if [ $HELP -eq 0 ]
    then
        for arg in $CFG_CONFIGURE_ARGS
        do
            if [ "$arg" = "--${FLAG}-${OP}" ]
            then
                OP=$(echo $OP | tr 'a-z-' 'A-Z_')
                FLAG=$(echo $FLAG | tr 'a-z' 'A-Z')
                local V="CFG_${FLAG}_${OP}"
                eval $V=1
                putvar $V
            fi
        done
    else
        if [ ! -z "$META" ]
        then
            OP="$OP=<$META>"
        fi
        printf "    --%-30s %s\n" "$FLAG-$OP" "$DOC"
     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
need_cmd sed


msg "inspecting environment"

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

if [ $CFG_OSTYPE = Darwin -a $CFG_CPUTYPE = i386 ]
then
    # Darwin's `uname -s` lies and always returns i386. We have to use sysctl
    # instead.
    if sysctl hw.optional.x86_64 | grep ': 1'
    then
        CFG_CPUTYPE=x86_64
    fi
fi


# The goal here is to come up with the same triple as LLVM would,
# at least for the subset of platforms we're willing to target.

case $CFG_OSTYPE in

    Linux)
        CFG_OSTYPE=unknown-linux-gnu
        ;;

    FreeBSD)
        CFG_OSTYPE=unknown-freebsd
        ;;

    Darwin)
        CFG_OSTYPE=apple-darwin
        ;;

    MINGW32*)
        CFG_OSTYPE=pc-mingw32
        ;;

    *)
        err "unknown OS type: $CFG_OSTYPE"
        ;;
esac


case $CFG_CPUTYPE in

    i386 | i486 | i686 | i786 | x86)
        CFG_CPUTYPE=i686
        ;;

    xscale | arm)
        CFG_CPUTYPE=arm
        ;;

    x86_64 | x86-64 | x64)
	# FIME: Once we do a 64-bit build this should be x86_64
        CFG_CPUTYPE=i686
        ;;

    *)
        err "unknown CPU type: $CFG_CPUTYPE"
esac

CFG_HOST_TRIPLE="${CFG_CPUTYPE}-${CFG_OSTYPE}"

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

OPTIONS=""
HELP=0
if [ "$1" = "--help" ]
then
    HELP=1
    shift
    echo ""
    echo "Usage: $CFG_SELF [options]"
    echo ""
    echo "Options:"
    echo ""
else
    msg "recreating config.mk"
    echo '' >config.mk

    step_msg "processing $CFG_SELF args"
fi

opt sharedstd 1 "build libstd as a shared library"
opt valgrind 1 "run tests with valgrind"
opt docs     1 "build documentation"
opt optimize 1 "build optimized rust code"
opt optimize-cxx 1 "build optimized C++ code"
opt mingw-cross 0 "cross-compile for win32 using mingw"
opt clang 0 "prefer gcc to clang for building the runtime"
opt debug-llvm 0 "build LLVM in debug mode"
valopt prefix "/usr/local" "set installation prefix"
valopt llvm-root "" "set LLVM root"
valopt target-triples "" "LLVM target triples (defaults to host if unset)"

if [ $HELP -eq 1 ]
then
    echo ""
    exit 0
fi


step_msg "looking for build programs"

probe_need CFG_PERL         perl
probe_need CFG_PYTHON       python
probe_need CFG_CURL         curl

probe CFG_GIT              git
probe CFG_CLANG            clang++
probe CFG_GCC              gcc
probe CFG_LLVM_CONFIG      llvm-config
probe CFG_VALGRIND         valgrind
probe CFG_PERF             perf
probe CFG_MAKEINFO         makeinfo
probe CFG_TEXI2PDF         texi2pdf
probe CFG_TEX              tex
probe CFG_MAKENSIS         makensis
probe CFG_NATURALDOCS      naturaldocs

if [ -z "$CFG_ENABLE_CLANG" -a -z "$CFG_GCC" ]
then
    err "either clang or gcc is required"
fi

if [ ! -z "$CFG_LLVM_ROOT" -a -e "$CFG_LLVM_ROOT/bin/llvm-config" ]
then
    step_msg "using custom LLVM at $CFG_LLVM_ROOT"

    LLVM_CONFIG="$CFG_LLVM_ROOT/bin/llvm-config"
    LLVM_VERSION=$($LLVM_CONFIG --version)

    case $LLVM_VERSION in
	(3.0svn | 3.0 | 3.1svn)
	    msg "found ok version of LLVM: $LLVM_VERSION"
	    ;;
	(*)
	    err "bad LLVM version: $LLVM_VERSION, need >=3.0svn"
	    ;;
    esac
fi

if [ ! -z "$CFG_ENABLE_CLANG" ]
then
    if [ -z "$CFG_CLANG" ]
    then
	err "clang requested but not found"
    fi
    CFG_CLANG_VERSION=$("$CFG_CLANG" \
                      --version \
                      | grep version \
                      | cut -d ' ' -f 3)

    case $CFG_CLANG_VERSION in
        (3.0svn | 3.0)
        step_msg "found ok version of CLANG: $CFG_CLANG_VERSION"
        CFG_C_COMPILER="clang"
        ;;
        (*)
        err "bad CLANG version: $CFG_CLANG_VERSION, need >=3.0svn"
        ;;
    esac
else
    CFG_C_COMPILER="gcc"
fi

if [ -z "$CFG_PREFIX" ]
then
    CFG_PREFIX=/usr/local
fi

if [ -z "$CFG_TARGET_TRIPLES" ]
then
    CFG_TARGET_TRIPLES="${CFG_HOST_TRIPLE}"
else
    CFG_TARGET_TRIPLES="${CFG_TARGET_TRIPLES/,/ }"
fi


step_msg "making directories"

for i in \
    doc doc/std \
    nd nd/std \
    dl \
    test/run-pass test/run-fail test/compile-fail \
    test/bench test/perf test/pretty
do
    make_dir $i
done

make_dir llvm
for t in $CFG_TARGET_TRIPLES
do
    make_dir llvm/$t
done

make_dir rustllvm
for t in $CFG_TARGET_TRIPLES
do
    make_dir rustllvm/$t
done

make_dir rt
for t in $CFG_TARGET_TRIPLES
do
  make_dir rt/$t
  for i in                                          \
    isaac bigint sync test arch/i386 arch/x86_64    \
    libuv libuv/src/ares libuv/src/eio libuv/src/ev
  do
    make_dir rt/$t/$i
  done
done

for t in $CFG_TARGET_TRIPLES
do
    for i in 0 1 2 3
    do
        # host bin dir
        make_dir stage$i/bin

        # host lib dir
        make_dir stage$i/lib

        # target bin dir
        make_dir stage$i/lib/rustc/$t/bin

        # target lib dir
        make_dir stage$i/lib/rustc/$t/lib
    done
done


# Configure submodules
step_msg "configuring submodules"

# Have to be in the top of src directory for this
cd ${CFG_SRC_DIR}

SUBMODULE_STATUS=$("${CFG_GIT}" submodule status)
NEED_INIT_COUNT=$(echo "$SUBMODULE_STATUS" | grep -c "^-")
NEED_UPDATE_COUNT=$(echo "$SUBMODULE_STATUS" | grep -c "^+")
NEED_INIT=$(test $NEED_INIT_COUNT -gt 0)$?
NEED_UPDATE=$(test "($NEED_INIT)" -o "$NEED_UPDATE_COUNT" -gt 0)$?

if [ $NEED_INIT ]
then
    msg "git: submodule init"
    "${CFG_GIT}" submodule init --quiet
fi

if [ $NEED_UPDATE ]
then
    msg "git: submodule update"
    "${CFG_GIT}" submodule update --quiet
fi

cd ${CFG_BUILD_DIR}


# Configure llvm. Here we go...
CFG_LLVM_SRC_DIR=${CFG_SRC_DIR}src/llvm

for t in $CFG_TARGET_TRIPLES
do
    if [ -z $CFG_LLVM_ROOT ]
    then
	step_msg "configuring LLVM for $t"

	LLVM_BUILD_DIR=$CFG_BUILD_DIR/llvm/$t

	LLVM_TARGETS="--enable-targets=x86,x86_64"
	LLVM_BUILD="--build=$t"
	LLVM_HOST="--host=$t"
	LLVM_TARGET="--target=$t"
    if [ ! -z "$CFG_ENABLE_DEBUG_LLVM" ]
    then
        LLVM_DBG_OPTS=""
        # Just use LLVM straight from its build directory to
        # avoid 'make install' time
	    LLVM_INST_DIR=$LLVM_BUILD_DIR/Debug+Asserts
    else
        LLVM_DBG_OPTS="--enable-optimized"
	    LLVM_INST_DIR=$LLVM_BUILD_DIR/Release+Asserts
    fi
	LLVM_OPTS="$LLVM_DBG_OPTS --disable-docs"

	LLVM_CXX_32="g++ -m32"
	LLVM_CC_32="gcc -m32"
	LLVM_CFLAGS_32="-m32"
	LLVM_CXXFLAGS_32="-m32"
	LLVM_LDFLAGS_32="-m32"

        # FIXME: Need to change flags for x64
	LLVM_CXX=$LLVM_CXX_32
	LLVM_CC=$LLVM_CC_32
	LLVM_CFLAGS=$LLVM_CFLAGS_32
	LLVM_CXXFLAGS=$LLVM_CXXFLAGS_32
	LLVM_LDFLAGS=$LLVM_LDFLAGS_32

	CXX=$LLVM_CXX
	CC=$LLVM_CC
	CFLAGS=$LLVM_CFLAGS
	CXXFLAGS=$LLVM_CXXFLAGS
	LDFLAGS=$LLVM_LDFLAGS

	LLVM_FLAGS="$LLVM_TARGETS $LLVM_OPTS $LLVM_BUILD $LLVM_HOST $LLVM_TARGET"

	msg "configuring LLVM with:"
	msg "$LLVM_FLAGS"

	export CXX
	export CC
	export CFLAGS
	export CXXFLAGS
	export LDFLAGS

	cd $LLVM_BUILD_DIR
	case $CFG_SRC_DIR in
	    /* | [a-z]:* | [A-Z]:*)
		${CFG_LLVM_SRC_DIR}/configure $LLVM_FLAGS
		;;
	    *)
		${CFG_BUILD_DIR}/${CFG_LLVM_SRC_DIR}/configure $LLVM_FLAGS
		;;
	esac
	cd $CFG_BUILD_DIR
    else
	LLVM_BUILD_DIR=
        # The user is using their own LLVM
	LLVM_INST_DIR=$CFG_LLVM_ROOT
    fi

    # Construct variables for LLVM build and install directories for
    # each target. These will be named
    # CFG_LLVM_BUILD_DIR_${target_triple} but all the hyphens in
    # target_triple will be converted to underscore, because bash
    # variables can't contain hyphens. The makefile will then have to
    # convert back.
    CFG_LLVM_BUILD_DIR=$(echo CFG_LLVM_BUILD_DIR_${t} | tr - _)
    CFG_LLVM_INST_DIR=$(echo CFG_LLVM_INST_DIR_${t} | tr - _)
    eval ${CFG_LLVM_BUILD_DIR}="'$LLVM_BUILD_DIR'"
    eval ${CFG_LLVM_INST_DIR}="'$LLVM_INST_DIR'"
done


step_msg "writing configuration"

putvar CFG_SRC_DIR
putvar CFG_BUILD_DIR
putvar CFG_OSTYPE
putvar CFG_CPUTYPE
putvar CFG_CONFIGURE_ARGS
putvar CFG_HOST_TRIPLE
putvar CFG_TARGET_TRIPLES
putvar CFG_C_COMPILER
putvar CFG_PREFIX

if head -n 1 ${CFG_SRC_DIR}src/snapshots.txt | grep -q '^T'
then
    CFG_IN_TRANSITION=1
    putvar CFG_IN_TRANSITION
fi

# Valgrind is only reliable on Linux. On Windows it doesn't work at all, and
# on the Mac the dynamic linker causes Valgrind to emit a huge stream of
# errors.
if [ $CFG_OSTYPE != unknown-linux-gnu ] && [ $CFG_OSTYPE != apple-darwin ]
then
    CFG_BAD_VALGRIND=1
    putvar CFG_BAD_VALGRIND
fi

putvar CFG_LLVM_ROOT
putvar CFG_LLVM_SRC_DIR

for t in $CFG_TARGET_TRIPLES
do
    CFG_LLVM_BUILD_DIR=$(echo CFG_LLVM_BUILD_DIR_${t} | tr - _)
    CFG_LLVM_INST_DIR=$(echo CFG_LLVM_INST_DIR_${t} | tr - _)
    putvar $CFG_LLVM_BUILD_DIR
    putvar $CFG_LLVM_INST_DIR
done


# 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

msg
copy ${CFG_SRC_DIR}Makefile.in ./Makefile

step_msg "complete"