#!/usr/bin/env bash
#
# TROUBLESHOOTING
#   - To enable verbose algorithm/implementation debugging, use ./build -DDEBUG
#   - If you see 'undefined reference to `clock_gettime'', try ./build -lrt instead
#
# BUGS
#   masterpassword@lyndir.com
#
# AUTHOR
#   Maarten Billemont
#
cd "${BASH_SOURCE%/*}"
shopt -s extglob
set -e


### CONFIGURATION

# Targets to build.
if [[ $targets ]]; then
    read -ra targets <<< "$targets"
else
    # Default targets.
    # Modify here or override using targets='mpw mpw-bench' ./build
    targets=(
        mpw                         # C CLI version of Master Password.
       #mpw-bench                   # C CLI Master Password benchmark utility.
    )
fi


### DEPENDENCIES

fetch() {
    if hash wget 2>/dev/null; then
        wget -O "${1##*/}" "$1"
    elif hash curl 2>/dev/null; then
        curl "$1" > "${1##*/}"
    fi
}
unpack() {
    if [[ $1 = *.tar.gz || $1 = *.tgz ]]; then
        tar -xvzf "$1"

    elif [[ $1 = *.tar.bz2 || $1 = *.tbz2 ]]; then
        tar -xvjf "$1"

    elif [[ $1 = *.tar ]]; then
        tar -xvf "$1"

    else
        echo 2>&1 "Don't know how to unpack: $1"
    fi

    printf 'Verifying package: %s, against digest: %s...' "$1" "$2"
    [[ $(openssl sha < "$1") = $2 ]] || {
        printf ' mismatch!\n'
        echo 2>&1 "Downloaded package doesn't match digest."
        exit 1
    }
    printf ' OK!\n'

    files=( !("$1") )
    if [[ -d $files ]] && (( ${#files[@]} == 1 )); then
        mv "$files"/* .
        rmdir "$files"
    fi
}
fetchSource() (
    source .source

    if [[ $pkg && -e "${pkg##*/}" ]]; then
        files=( !("${pkg##*/}") )
        [[ -e $files ]] || {
            echo
            echo "Unpacking: ${PWD##*/}, using package..."
            unpack "${pkg##*/}" "$pkg_sha"
        }

    elif [[ $git ]] && hash git 2>/dev/null; then
        [[ -e .git ]] || {
            echo
            echo "Fetching: ${PWD##*/}, using git..."
            git clone "$svn" .
            printf '%s' "$(git describe --always)" > "${PWD##*/}-version"
        }

    elif [[ $svn ]] && hash git 2>/dev/null && [[ -x "$(git --exec-path)/git-svn" ]]; then
        [[ -e .git ]] || {
            echo
            echo "Fetching: ${PWD##*/}, using git-svn..."
            git svn clone --prefix=origin/ --stdlayout "$svn" .
            printf '%s' "$(git describe --always)" > "${PWD##*/}-version"
        }

    elif [[ $svn ]] && hash svn 2>/dev/null; then
        [[ -e .svn ]] || {
            echo
            echo "Fetching: ${PWD##*/}, using svn..."
            svn checkout "$svn/trunk" .
            printf 'r%s' "$(svn info | awk '/^Revision:/{ print $2 }')" > "${PWD##*/}-version"
        }

    elif [[ $pkg ]]; then
        files=( !("${pkg##*/}") )
        [[ -e $files ]] || {
            echo
            echo "Fetching: ${PWD##*/}, using package..."
            fetch "$pkg"
            unpack "${pkg##*/}" "$pkg_sha"
        }

    else

        echo >&2 "error: Missing git-svn or svn."
        echo >&2 "error: Please install either or manually check out the sources"
        echo >&2 "error: from: $home"
        echo >&2 "error: into: $PWD"
        exit 1
    fi
)
depend() {

    echo
    echo "Checking dependency: $1..."
    [[ -e "lib/$1/.built" ]] && return

    pushd "lib/$1"
    fetchSource

    echo
    echo "Configuring dependency: $1..."
    if [[ -e configure.ac ]]; then
        if [[ ! -e configure ]]; then
            # create configure using autotools.
            if ! hash aclocal || ! hash automake; then
                echo >&2 "Need autotools to build $1.  Please install automake and autoconf."
                exit 1
            fi

            aclocal
            autoheader
            autoconf
            mkdir -p config.aux
            automake --add-missing
        fi
    fi

    if [[ -e configure ]]; then
        ./configure
    fi

    echo
    echo "Building dependency: $1..."
    if [[ -e Makefile ]]; then
        if ! hash make; then
            echo >&2 "Need make to build $1.  Please install GNU make."
            exit 1
        fi

        make
        date > .built
    else
        echo >&2 "error: Don't know how to build: $1"
        exit 1
    fi
    popd
}


### MPW
mpw() {
    depend scrypt

    echo
    echo "Building target: $target..."
    CFLAGS=(
        # include paths
        -I"lib/scrypt/lib" -I"lib/scrypt/libcperciva"
    )
    LDFLAGS=(
        # library paths
        -L"." -L"lib/scrypt"
        # link libraries
        -l"crypto"
        # scrypt
        "lib/scrypt/scrypt-crypto_aesctr.o"
        "lib/scrypt/scrypt-sha256.o"
        "lib/scrypt/scrypt-crypto_scrypt-nosse.o"
        "lib/scrypt/scrypt-memlimit.o"
        "lib/scrypt/scrypt-scryptenc_cpuperf.o"
        "lib/scrypt/scrypt-scryptenc.o"
    )

    cc "${CFLAGS[@]}"                 -c types.c -o types.o "$@"
    cc "${CFLAGS[@]}" "${LDFLAGS[@]}" "types.o" mpw.c -o mpw "$@"
    echo "done!  Now run ./install or use ./mpw"
}


### MPW-BENCH
mpw-bench() {
    depend scrypt
    depend bcrypt

    echo
    echo "Building target: $target..."
    CFLAGS=(
        # include paths
        -I"lib/scrypt/lib" -I"lib/scrypt/libcperciva"
        -I"lib/bcrypt" 
    )
    LDFLAGS=(
        # library paths
        -L"." -L"lib/scrypt"
        -L"lib/bcrypt"
        # libraries
        -l"crypto"
        # scrypt
        "lib/scrypt/scrypt-crypto_aesctr.o"
        "lib/scrypt/scrypt-sha256.o"
        "lib/scrypt/scrypt-crypto_scrypt-nosse.o"
        "lib/scrypt/scrypt-memlimit.o"
        "lib/scrypt/scrypt-scryptenc_cpuperf.o"
        "lib/scrypt/scrypt-scryptenc.o"
        # bcrypt
        "lib/bcrypt/crypt_blowfish.o"
        "lib/bcrypt/crypt_gensalt.o"
        "lib/bcrypt/wrapper.o"
        "lib/bcrypt/x86.o"
    )

    cc "${CFLAGS[@]}"                 -c types.c -o types.o "$@"
    cc "${CFLAGS[@]}" "${LDFLAGS[@]}" "types.o" mpw-bench.c -o mpw-bench "$@"
    echo "done!  Now use ./mpw-bench"
}


### TARGETS

cc() {
    if hash llvm-gcc 2>/dev/null; then
        llvm-gcc "$@"
    elif hash gcc 2>/dev/null; then
        gcc -std=gnu99 "$@"
    elif hash clang 2>/dev/null; then
        clang "$@"
    else
        echo >&2 "Need a compiler.  Please install GCC or LLVM."
        exit 1
    fi
}

echo "Will build targets: ${targets[*]}..."
for target in "${targets[@]}"; do
    "$target" "$@"
done