#!/usr/bin/env bash
trap spm_build_cleanup EXIT
THIS_SCRIPT=$(dirname ${BASH_SOURCE[0]})

function pushd() {
    command pushd "$@" >/dev/null
}

function popd() {
    command popd >/dev/null
}

function _msg() {
    marker="$1"
    shift
    args="$@"
    printf '%s %s\n' "${marker}" "${args}"
}

function msg() {
    _msg "=>" "$@"
}

function msg2() {
    _msg " *" "$@"
}

function msg3() {
    _msg "  >" "$@"
}

function msg_fail() {
    _msg "FAILED:" "$@"
}

function msg_error() {
    _msg "ERROR:" "$@"
}

function msg_warn() {
    _msg "WARNING:" "$@"
}

function tar() {
    local cmd=bsdtar
    $cmd "$@"
}

function spm_debug_shell() {
    local where

    where="${1}"
    if [[ -z "${where}" ]] || [[ ! -d "${where}" ]]; then
        where="$(pwd)"
    fi

    pushd "${where}" || exit 1

    PS1="(SPMBUILD DEBUG)$ "
    export PS1

    echo "ENTERING DEBUG SHELL"
    env bash

    # Exiting here prevents the user from leaving debug calls in their build scripts
    # (i.e. when this function is used, no package archives will be generated)
    exit 1
}

function spm_build_initialize_stage1() {
    rp=$(which realpath 2>/dev/null \
        || which spm_realpath 2>/dev/null \
        || echo ./spm_realpath)
    export SPMDEV=$($rp "${THIS_SCRIPT}/../src/spm" 2>/dev/null)
    export SPM=$(which spm 2>/dev/null || echo ${SPMDEV})

    spm_build_check_rt_env
    if [[ $? != 0 ]]; then
        msg_error "spm self-test failed"
        exit 1
    fi

    if [[ ! -f ${SPM} ]]; then
        msg_error "Could not locate 'spm'"
        exit 1
    fi

    export SPM_BUILD_SYS_TARGET=$(spm_build_get_sys_target)

    export SPM_BUILD_STORE="${HOME}/.spm/build"
    if [[ ! -d ${SPM_BUILD_STORE} ]]; then
        mkdir -p "${SPM_BUILD_STORE}"
        if [[ $? != 0 ]]; then
            msg_error "SPM_BUILD_STORE creation failed: ${SPM_BUILD_STORE}"
            exit 1
        fi
    fi

    export SPM_BUILD_STORE_SOURCES="${SPM_BUILD_STORE}/sources"
    if [[ ! -d ${SPM_BUILD_STORE_SOURCES} ]]; then
        mkdir -p "${SPM_BUILD_STORE_SOURCES}"
        if [[ $? != 0 ]]; then
            msg_error "SPM_BUILD_STORE_SOURCES creation failed: ${SPM_BUILD_STORE_SOURCES}"
            exit 1
        fi
    fi

    export SPM_BUILD_STORE_PACKAGES="${SPM_BUILD_STORE}/pkgs"
    if [[ ! -d ${SPM_BUILD_STORE_PACKAGES} ]]; then
        mkdir -p "${SPM_BUILD_STORE_PACKAGES}"
        if [[ $? != 0 ]]; then
            msg_error "SPM_BUILD_STORE_PACKAGES creation failed: ${SPM_BUILD_STORE_PACKAGES}"
            exit 1
        fi
    fi

    # Set global TMPDIR to *help* prevent cluttering the system's temporary storage directory
    export TMPDIR="${SPM_BUILD_STORE}/tmp"
    if [[ ! -d ${TMPDIR} ]]; then
        mkdir -p "${TMPDIR}"
        if [[ $? != 0 ]]; then
            msg_error "TMPDIR creation failed: ${TMPDIR}"
            exit 1
        fi
    fi
}

function spm_build_new_root() {
    local path

    path=$(mktemp)
    if [[ ! -f "${path}" ]]; then
        msg_error "spm_build_new_root: failed to create temporary file"
        exit 1
    fi
    spm_build_mkruntime "$1" > "${path}"
    source "${path}"
    rm -f "${path}"
}

function spm_build_initialize_stage2() {
    # In order to get the SPM_* variables out spm, we need to give a path...
    # this is ugly but safe-ish
    spm_build_new_root "/usr"

    unset CFLAGS
    unset CPPFLAGS
    unset LDFLAGS
    unset FCFLAGS

    # All templates strings MUST be the same length to allow for proper relocation
    export _SPM_BUILD_ROOT_TEMPLATE="${TMPDIR}/spmbuild_root_XXXXXXXXX"
    export _SPM_BUILD_RUNTIME_TEMPLATE="${TMPDIR}/spmbuild_runtime_XXXXXX"
    export _SPM_BUILD_PKGDIR_TEMPLATE="${TMPDIR}/spmbuild_pkgdir_XXXXXXX"

    export SPM_BUILD_ROOT_BASE=$(mktemp -d "${_SPM_BUILD_ROOT_TEMPLATE}")
    export SPM_BUILD_ROOT="${SPM_BUILD_ROOT_BASE}/${SPM_META_PREFIX_PLACEHOLDER}"
    export _srcdir="${SPM_BUILD_ROOT}"
    mkdir -p "${SPM_BUILD_ROOT}"
    if [[ ! -d ${SPM_BUILD_ROOT} ]]; then
        msg_error "SPM_BUILD_ROOT creation failed: ${SPM_BUILD_ROOT}"
        exit 1
    fi

    export SPM_BUILD_RUNTIME_BASE=$(mktemp -d "${_SPM_BUILD_RUNTIME_TEMPLATE}")
    export SPM_BUILD_RUNTIME="${SPM_BUILD_RUNTIME_BASE}/${SPM_META_PREFIX_PLACEHOLDER}"
    export _runtime="${SPM_BUILD_RUNTIME}"

    mkdir -p "${SPM_BUILD_RUNTIME}"
    if [[ ! -d ${SPM_BUILD_RUNTIME} ]]; then
        msg_error "SPM_BUILD_RUNTIME creation failed: ${SPM_BUILD_RUNTIME}"
        exit 1
    fi

    export SPM_BUILD_PKGDIR_BASE=$(mktemp -d "${_SPM_BUILD_PKGDIR_TEMPLATE}")
    export SPM_BUILD_PKGDIR="${SPM_BUILD_PKGDIR_BASE}/${SPM_META_PREFIX_PLACEHOLDER}"
    export _pkgdir="${SPM_BUILD_PKGDIR}"

    mkdir -p "${SPM_BUILD_PKGDIR}"
    if [[ ! -d ${SPM_BUILD_PKGDIR} ]]; then
        msg_error "SPM_BUILD_PKGDIR creation failed: ${SPM_BUILD_PKGDIR}"
        exit 1
    fi

    # _prefix is a not a real path. do not create it!
    # _prefix is double-wide
    export SPM_BUILD_PREFIX="/${SPM_META_PREFIX_PLACEHOLDER}${SPM_META_PREFIX_PLACEHOLDER}"
    export _prefix="${SPM_BUILD_PREFIX}"

    export SPM_BUILD_CRUMBS="${SPM_BUILD_PREFIX} ${SPM_BUILD_ROOT} ${SPM_BUILD_RUNTIME} ${SPM_BUILD_PKGDIR}"

    export _maxjobs="$(getconf _NPROCESSORS_ONLN 2>/dev/null)"
    if (( ${_maxjobs} > 1 )); then
        _maxjobs=$((_maxjobs - 1))
    elif [[ -z ${_maxjobs} ]]; then
        _maxjobs=1
    fi

    spm_build_new_root "${SPM_BUILD_RUNTIME}"
    LD_LIBRARY_PATH="${SPM_BUILD_RUNTIME}/lib:${SPM_BUILD_RUNTIME}/lib64"
    LD_RUN_PATH="${LD_LIBRARY_PATH}"

    if [[ $(uname -s) == Linux ]]; then
        export LD_LIBRARY_PATH
        export LD_RUN_PATH
    elif [[ $(uname -s) == Darwin ]]; then
        # Darwin is ridiculous. Don't rely on DYLD_* anything.
        unset DYLD_LIBRARY_PATH
        unset LD_LIBRARY_PATH
        unset LD_RUN_PATH
    #elif # ... another OS's equivalent variable here
    fi

    export PKG_CONFIG_ALLOW_SYSTEM_CFLAGS=1
    export PKG_CONFIG_ALLOW_SYSTEM_LIBS=1
}

spm_build_cleaned=0
export spm_build_cleaned
function spm_build_cleanup() {
    # Don't clean up more than once
    if (( spm_build_cleaned > 0)); then
      return
    fi

    if [[ ${keep} != 0 ]]; then
        msg "Temporary storage not destroyed"
        msg2 "${SPM_BUILD_ROOT_BASE}"
        msg2 "${SPM_BUILD_RUNTIME_BASE}"
        msg2 "${SPM_BUILD_PKGDIR_BASE}"
        return
    fi
    [[ -d ${SPM_BUILD_ROOT_BASE} ]] && rm -rf ${SPM_BUILD_ROOT_BASE}
    [[ -d ${SPM_BUILD_RUNTIME_BASE} ]] && rm -rf ${SPM_BUILD_RUNTIME_BASE}
    [[ -d ${SPM_BUILD_PKGDIR_BASE} ]] && rm -rf ${SPM_BUILD_PKGDIR_BASE}
    spm_build_cleaned=1
}

function spm_build_install() {
    ${SPM} --verbose --yes --override-manifests --manifest "${SPM_BUILD_STORE_PACKAGES}" --install $@ --root "${SPM_BUILD_RUNTIME}"
}

function spm_build_mkprefixbin() {
    ${SPM} --yes --cmd mkprefixbin $@
}

function spm_build_mkprefixtext() {
    ${SPM} --yes --cmd mkprefixtext $@
}

function spm_build_mkmanifest() {
    ${SPM} --yes --cmd mkmanifest $@
}

function spm_build_mkruntime() {
    ${SPM} --yes --cmd mkruntime "${1}"
}

function spm_build_rpath_set() {
    ${SPM} --yes --cmd rpath_set $@
}

function spm_build_rpath_autoset() {
    ${SPM} --yes --cmd rpath_autoset $@
}

function spm_build_get_package_ext() {
    ${SPM} --yes --cmd get_package_ext
}

function spm_build_get_sys_target() {
    ${SPM} --yes --cmd get_sys_target
}

function spm_build_check_rt_env() {
    ${SPM} --yes --cmd check_rt_env
}

function spm_build_fetch() {
    local filename
    local tmpdir

    if (( $# < 2 )); then
        msg_error "spm_build_fetch: {url} {destination}"
        spm_build_cleanup
        exit 1
    fi

    tmpdir=$(mktemp -d)
    if [[ ! -d ${tmpdir} ]]; then
        msg_error "could not create temporary directory"
        spm_build_cleanup
        exit 1
    fi

    pushd ${tmpdir}
        # file already exists?
        if [[ -f "${2}/$(basename ${1})" ]]; then
            return
        fi

        # download file
        curl -LO "${1}"
        filename="$(find . -type f)"
        mkdir -p "${2}"
        mv "${filename}" "${2}"
    popd
    rm -rf "${tmpdir}"
}

function spm_build_do_sources() {
    local name="${1}"
    local remote
    for remote in "${sources[@]}"; do
        spm_build_fetch "${remote}" ${SPM_BUILD_STORE_SOURCES}/${name}
    done
}

function spm_build_mkdepends() {
    local filename="${1}"
    shift
    local deps=("$@")

    > "${filename}"
    for dep in "${deps[@]}"; do
        echo "${dep}" >> "${filename}"
    done
}

function spm_build_mkdesc() {
    local filename="${1}"
    if [[ -z ${filename} ]]; then
        msg_error "spm_build_mkdesc requires a path"
        exit 1
    fi
    echo "# SPM PACKAGE DESCRIPTOR
name=${name:-*}
version=${version:-*}
revision=${revision:-*}
license=${license:-*}
homepage=${homepage:-*}
summary=${summary:-*}
" > "${filename}"
}

function spm_build_mkfilelist() {
    local filename="${1}"

    if [[ -z ${filename} ]]; then
        msg_error "spmbuild_mkfilelist requires an output filename"
        exit 1
    fi

    echo "# SPM PACKAGE FILE LIST" > "${filename}"
    find . -type f -not -name ".SPM_*" >> "${filename}"
}

function prepare() {
    # stub
    :
}

function build() {
    # stub
    :
}

function package() {
    msg_error "package() function missing"
    exit 1
}

function spm_build_do_stage_prepare() {
    prepare
    set +x
}

function spm_build_do_stage_build() {
    build
    set +x
}

function spm_build_do_stage_package() {
    package
    set +x
}

function spm_build_tar() {
    local archive="${1}"
    bsdtar -c -z -f "${archive}" \
    --exclude '..' \
    --exclude '.' \
    .* *
}

function spm_build_do_stage_archive() {
    local archive="${1}"

    pushd "${SPM_BUILD_PKGDIR}"
        # Enter the "prefix" (i.e. strip off the leading slash)
        pushd "${SPM_BUILD_PREFIX#\/}"
            msg2 "Recording binary prefixes..."
            spm_build_mkprefixbin "${SPM_META_PREFIX_BIN}" . ${SPM_BUILD_CRUMBS}
            msg2 "Recording text prefixes..."
            spm_build_mkprefixtext "${SPM_META_PREFIX_TEXT}" . ${SPM_BUILD_CRUMBS}
            msg2 "Recording dependencies..."
            spm_build_mkdepends "${SPM_META_DEPENDS}" "${depends[@]}"
            msg2 "Recording package data..."
            spm_build_mkdesc "${SPM_META_DESCRIPTOR}"
            msg2 "Recording paths..."
            spm_build_mkfilelist "${SPM_META_FILELIST}"
            msg2 "Archiving files..."
            spm_build_tar "${archive}"
        popd
    popd
}

function spm_build_declare_metadata() {
    # Declare package metadata we need at this level
    package_name="${name}-${version}-${revision}"
    package_archive="${package_name}$(spm_build_get_package_ext)"
    package_target="${SPM_BUILD_STORE_PACKAGES}/${SPM_BUILD_SYS_TARGET}"
    package_final="${package_target}/${package_archive}"
}

function spm_build_update_metadata() {
    spm_build_declare_metadata
}

# -- main --
export keep=${keep:-0}
export SPM_BUILD_SCRIPT="build.sh"
export SPM_BUILD_SCRIPT_ROOT="$1"

if [[ ! -d ${SPM_BUILD_SCRIPT_ROOT} ]] || [[ ! -f ${SPM_BUILD_SCRIPT_ROOT}/${SPM_BUILD_SCRIPT} ]]; then
    msg_error "Need a directory containing a build script (${SPM_BUILD_SCRIPT})"
    exit 1
fi

msg "Initializing..."
spm_build_initialize_stage1
spm_build_initialize_stage2  # post-runtime activation

msg2 "Sourcing build script..."
source "${SPM_BUILD_SCRIPT_ROOT}/${SPM_BUILD_SCRIPT}"

spm_build_declare_metadata

if [[ ! -d "${package_target}" ]]; then
    mkdir -p ${package_target}
    spm_build_mkmanifest "${package_target}"
fi

msg2 "Downloading source files..."
spm_build_do_sources "${package_name}"

msg3 "Copying source files..."
rsync -avi "${SPM_BUILD_STORE_SOURCES}/${package_name}/" "${SPM_BUILD_ROOT}"
rsync -avi --exclude "${SPM_BUILD_SCRIPT}" "${SPM_BUILD_SCRIPT_ROOT}/" "${SPM_BUILD_ROOT}"

ls -l "${SPM_BUILD_ROOT}"

msg "Environment data"
printenv | grep -E '^SPM_' | sort
printenv | grep -E '^[A-Z]{0,3}FLAGS' | sort

msg "Processing ${package_name}"

set -e
if [[ ${#build_depends[@]} != 0 ]]; then
    msg2 "Installing build dependencies"
    spm_build_install "${build_depends[@]}"
fi

if [[ ${#depends[@]} != 0 ]]; then
    msg2 "Installing runtime dependencies"
    spm_build_install "${depends[@]}"
fi

if [[ ${name} != "filesystem" ]]; then
    depends=(filesystem "${depends[@]}")
fi

pushd "${SPM_BUILD_ROOT}"
    msg2 "prepare()"
    spm_build_do_stage_prepare
    msg2 "build()"
    spm_build_do_stage_build
    msg2 "package()"
    spm_build_do_stage_package
popd

msg "Create package: ${package_final}"
spm_build_do_stage_archive "${package_final}"

msg "Update manifest"
spm_build_mkmanifest "${package_target}"

msg "Clean"
spm_build_cleanup