#!/bin/bash
TMPDIR=${TMPDIR:-/tmp}

default_script=build.sh
build_order=scripts/build.order

build_scripts=$(cat ${build_order})

# TODO: Make this part of MKTC
SPM_PROG_RELOC=$HOME/Documents/work/reloc/reloc
SPM_PREFIX_BIN=.SPM_PREFIX_BIN
SPM_PREFIX_TEXT=.SPM_PREFIX_TEXT
SPM_DEPENDS=.SPM_DEPENDS
SPM_VERBOSE=0

export prefix_placeholder=_0123456789_0123456789_0123456789_0123456789_0123456789_0123456789_0123456789_
export prefix="/${prefix_placeholder}"
export maxjobs=7
export pkgdir=$(pwd)/pkgs
mkdir -p ${pkgdir}
source include/9999-template.sh


function spm_abspath() {
    local filename="${1}"
    local start="$(dirname ${filename})"

    pushd "${start}" &>/dev/null
        end="$(pwd)"
    popd &>/dev/null

    if [[ -f ${filename} ]]; then
        end="${end}/$(basename ${filename})"
    fi

    echo "${end}"
}


function spm_rpath_nearest() {
    local cwd="$(pwd)"
    local start=$(dirname $(spm_abspath ${1}))
    local result=

    # Jump to location of file
    cd "$(dirname ${start})"

    # Scan upward until we find a "lib" directory
    # OR when:
    # - Top of filesystem is reached (pretty much total failure [missing local dep])
    # - Top of active environment is reached (post installation)
    # - Top of default installation prefix is reached (during packaging)
    while [[ $(pwd) != / ]]
    do
        result+="../"
        if [[ -d lib ]] || [[ $(pwd) == ${SPM_ENV} ]] || [[ $(pwd) == *${prefix} ]]; then
            result+="lib"
            break
        fi
        cd ..
    done

    # Sanitize: removing double-slashes (if any)
    result=${result/\/\//\/}

    # Return to where we were instantiated
    cd "${cwd}"

    echo "${result}"
}

function spm_gen_package_rpath() {
    local rpath_orig
    local rpath_new

    # Assimilate all file paths that contain an RPATH
    for path in $(find . -type f -not -name '.SPM-*')
    do
        readelf -d "${path}" 2>/dev/null | grep RPATH &>/dev/null
        if (( $? )); then
            continue
        fi
        rpath_orig="$(readelf -d "${path}" | grep RPATH | awk -F'[][]' '{ print $2 }')"
        rpath_new='$ORIGIN/'"$(spm_rpath_nearest ${path})"
        echo "${path}: ${rpath_orig} -> ${rpath_new}"
        patchelf --set-rpath "${rpath_new}" "${path}"
    done
}

function spm_gen_package_prefixes() {
    echo "Generating build prefix manifest"
    # Create record files
    >${SPM_PREFIX_BIN}
    >${SPM_PREFIX_TEXT}

    # Assimilate file path for anything containing our prefix
    local count_text=0
    local count_bin=0
    local count_total=0
    local prefixes=(
        ${prefix}
        ${build_runtime}
        ${build_root}
        ${destdir}
    )

    for pkg_prefix in "${prefixes[@]}"; do
        for path in $(find . -type f -not -name ".SPM_*"); do
            # Check for prefix
            grep -l "${pkg_prefix}" "${path}" &>/dev/null

            # Prefix present? (0: yes, 1: no)
            if (( $? )); then
                continue
            fi

            # Get file type
            local mimetype="$(file -i ${path} | awk -F': ' '{ print $2 }')"
            local outfile

            # Record prefix data
            if [[ ${mimetype} = *text/* ]]; then
                outfile=${SPM_PREFIX_TEXT}
                (( count_text++ ))
            else
                outfile=${SPM_PREFIX_BIN}
                (( count_bin++ ))
            fi

            echo "#${prefix}" >> "${outfile}"
            echo "${path}" >> "${outfile}"

        done
    done

    count_total=$(( count_text + count_bin ))
    if (( ${count_total} )); then
        echo "Text: ${count_text}"
        echo "Binary: ${count_bin}"
        echo "Total: ${count_total}"
    else
        echo "No prefixes detected"
    fi
}


function spm_gen_package_depends() {
    echo "Generating dependency manifest"
    local outfile="${SPM_DEPENDS}"
    >${outfile}

    for dep in "${depends[@]}"; do
        echo "${dep}" >> "${outfile}"
    done
}


_spm_install_depends=()
_spm_install_seen=()
function spm_install() {
    local pkg="$(pkg_match $1)"
    if [[ ! -f ${pkg} ]]; then
        echo "Package not found: ${pkg}" >&2
        exit 1
    fi

    local destroot="$2"
    if [[ -z ${destroot} ]]; then
        echo "destination root undefined" >&2
        exit 1
    elif [[ ! -d ${destroot} ]]; then
        mkdir -p "${destroot}"
    fi

    # extract package into temp directory
    local pkgtmp=$(mktemp -d ${TMPDIR}/spm.XXXX)
    pushd "${pkgtmp}" &>/dev/null
        echo "Unpacking: ${pkg}"
        tar xf "${pkg}"

        local prefix_base

        # relocate binaries
        if [[ -f ${SPM_PREFIX_BIN} ]]; then
            while read path; do
                if [[ -z $path ]]; then
                    continue
                elif [[ $path =~ ^# ]]; then
                    if [[ -z $path ]]; then
                        continue;
                    fi
                    prefix_base="${path#\#}"
                    continue
                fi

                if [[ ! -f $path ]]; then
                    echo "WARNING: ${path} does not exist!" >&2
                    continue
                fi

                if (( $SPM_VERBOSE )); then
                    if [[ $path =~ .pyc$ ]]; then
                        continue
                    fi
                    echo "Relocating binary paths: ${path}"
                fi
                ${SPM_PROG_RELOC} "${prefix_base}" "${destroot}" "${path}" 1>/dev/null
            done <<< $(cat "${SPM_PREFIX_BIN}")
            rm -f ${SPM_PREFIX_BIN}
        fi
        prefix_base=""

        # relocate text
        if [[ -f ${SPM_PREFIX_TEXT} ]]; then
            while read path; do
                if [[ -z $path ]]; then
                    continue
                elif [[ $path =~ ^# ]]; then
                    if [[ -z $path ]]; then
                        continue;
                    fi
                    prefix_base="${path#\#}"
                    continue
                fi

                if [[ ! -f $path ]]; then
                    echo "WARNING: ${path} does not exist!" >&2
                    continue
                fi
                if (( $SPM_VERBOSE )); then
                    if [[ $path =~ .pyc$ ]]; then
                        continue
                    fi
                    echo "Relocating text paths: ${path}"
                fi
                sed -i -e "s|${prefix_base}|${destroot}|g" "${path}"
            done <<< $(cat "${SPM_PREFIX_TEXT}")
            rm -f ${SPM_PREFIX_TEXT}
        fi

        # service package dependencies
        if [[ -f ${SPM_DEPENDS} ]]; then
            if [[ -z ${_spm_install_depends} ]]; then
                _spm_install_depends=($(cat ${SPM_DEPENDS}))
            else
                _spm_install_depends+=($(cat ${SPM_DEPENDS}))
            fi

            for dep in "${_spm_install_depends[@]}"; do
                # Track dependencies we have already processed to avoid infinite recursion
                if [[ "${_spm_install_seen[@]}" =~ "$dep" ]]; then
                    # Pop dependency and do nothing
                    _spm_install_depends=("${_spm_install_depends[@]:1}")
                    continue
                fi

                # Pop dependency and process it
                _spm_install_depends=("${_spm_install_depends[@]:1}")

                # Stop processing when the array is totally empty
                if (( ${#_spm_install_depends[@]} < 0 )); then
                    break
                fi

                _spm_install_seen+=("${dep}")
                spm_install "${dep}" "${destroot}"
            done
            rm -f "${SPM_DEPENDS}"
        fi

        # install package
        echo "Installing: ${pkg}"
        rsync -a ./ "${destroot}"

    popd &>/dev/null
    if [[ -d $pkgtmp ]]; then
        rm -rf "${pkgtmp}"
    fi
}


function builder() {
    for build_script in ${build_scripts}; do
        build_script=$(readlink -f scripts/$build_script/build.sh)
        build_script_root=$(dirname ${build_script})
        export build_root="${build_script_root}/buildroot"
        export build_runtime="${build_script_root}/runtime"
        export destdir="${build_script_root}/root"

        export CC=gcc
        export CXX=g++
        export LD_LIBRARY_PATH="${build_runtime}/lib"
        export CFLAGS="-I${build_runtime}/include"
        export CPPFLAGS="${CFLAGS}"
        export LDFLAGS="-L${build_runtime}/lib -Wl,-rpath="'\$$ORIGIN'"/../lib"

        echo "Building: ${build_script}"

        if [[ ! -f ${build_script} ]]; then
            echo "${build_script} does not exist, check ${build_order}" >&2
            exit 1
        fi

        if [[ -d ${build_root} ]]; then
            rm -rf ${build_root}
        fi
        mkdir -p ${build_root}

        if [[ -d ${build_runtime} ]]; then
            rm -rf ${build_runtime}
        fi
        mkdir -p ${build_runtime}

        if [[ -d ${destdir} ]]; then
            rm -rf ${destdir}
        fi
        mkdir -p ${destdir}

        export PATH="${build_runtime}/bin:${build_runtime}/sbin:$PATH"
        export PKG_CONFIG_PATH="${build_runtime}/lib/pkgconfig"

        pushd ${build_root} &>/dev/null
            source ${build_script}
            for url in "${sources[@]}"; do
                if [[ -f $(basename $url) ]]; then
                    continue
                fi
                echo "Downloading source: ${url}"
                curl -LO $url
            done

            for dep in "${depends[@]}"; do
                echo "Depends on: ${dep}"
                pkg=$(basename $(pkg_match "${dep}"))
                spm_install "${pkg}" "${build_runtime}"
            done
            hash -r

            set -e
            prepare
            build
            package
            set +e

            if [[ -d ${destdir} ]]; then
                pushd ${destdir} &>/dev/null
                    if [[ -d ${destdir}/${prefix} ]]; then
                        pushd ${destdir}/${prefix} &>/dev/null
                    fi
                    spm_gen_package_rpath
                    spm_gen_package_prefixes
                    spm_gen_package_depends

                    pkg="${pkgdir}/${name}-${version}-${revision}.tar.gz"
                    echo "Creating package: ${pkg}"
                    pwd
                    ls -la
                    tar cfz "${pkg}" .SPM_* .

                    if [[ -d ${destdir}/${prefix} ]]; then
                        popd &>/dev/null
                    fi
                popd &>/dev/null
            fi
        popd &>/dev/null
    done
}

function pkg_match() {
    if [[ -z $1 ]]; then
        echo "pkg_match: missing argument, package" >&2
        exit 1
    fi
    match=$(find "${pkgdir}" -type f -regex ".*/${1}\-?[0-9]+?.*" 2>/dev/null | sort | head -n 1)
    echo "${match}"
}

function installer() {
    local root=""
    local packages=()

    while [[ $# != 0 ]]; do
        case "$1" in
            --verbose|-v)
                SPM_VERBOSE=1
                ;;
            --root|-r)
                root="$2"
                shift
                ;;
            -*|--*)
                echo "installer: unknown argument: $1" >&2
                exit 1
                ;;
            *)
                # "Most-likely" match the requested package by name
                p=$(basename $(pkg_match "${1}"))
                packages+=("$p")
                ;;
        esac
        shift
    done

    if [[ -z $root ]]; then
        echo "missing required argument: --root {destination}" >&2
        exit 1
    fi

    export PATH="${root}/bin:${PATH}"
    for pkg in "${packages[@]}"; do
        spm_install "${pkg}" "${root}"
    done
}

function usage() {
echo "Usage: $0 [build|install] {package}

Options:
    --help    (-h)      this message
    --verbose (-v)      increase verbosity

Commands:
    build               build a package
    install             install a package

Positional arguments:
    package             package to interact with

"
}


if [[ $# < 2 ]]; then
    usage
    exit 1
fi

fn=
args=
while [[ $# != 0 ]]; do
    case "$1" in
        --verbose|-v)
            SPM_VERBOSE=1
            ;;
        --help|-h)
            usage
            exit 0
            ;;
        build)
            fn=builder
            if [[ $2 != "all" ]]; then
                build_scripts="$2"
                if [[ $build_scripts =~ .*/build.sh ]]; then
                    build_scripts=$(dirname ${build_scripts})
                fi
            fi
            shift 2
            break
            ;;

        install)
            fn=installer
            shift
            args=("$@")
            break
            ;;

        *)
            echo "unknown argument: $1"
            exit 1
            ;;
    esac
    shift
done

$fn "${args[@]}"