#!/usr/bin/env bash

set -euo pipefail

usage() {
    cat <<EOF
$0 [-u|--usage|-h|--help]
    [--list] [-n|--dry-run] [--xoname=NAME]
    [--repo
     |--add-umbrella-remote
     |--split-umbrella-remote
     |--pull-umbrella-remote
     |--push-umbrella-remote]
    [--clone|--configure|--build|--install]
    [--with-examples] [--with-utests] [--with-asm] [--debug-build]
    [--with-opengl=GLFLAG] [--with-vulkan=VKFLAG]
    [-S=SOURCEDIR] [-B=BUILDDIR]
    NAME
EOF
}

help() {
    usage

    cat <<EOF

fetch and/or build xo component libraries

Options:
  -u | --usage            brief help message
  -h | --help             this help message
  --list                  list known xo libraries
  -n | --dry-run          dry-run: don't actually invoke state-changing commands
  --xoname=NAME           operate on xo subsystem NAME
  --clone                 git clone xo library NAME in current directory
  --configure             run cmake for xo library NAME in immediate subdir
                          Will use NAME/.build as build directory
  --build                 run cmake build for xo library NAME in immediate subdir
  --build-docs            build documentation for xo library NAME in immediate subdir
  --install               run cmake install for xo library NAME in immediate subdir
  --realclean             nuke build directory

  -S=SOURCEDIR            override path/to/source
  -B=BUILDDIR             override path/to/build

  --with-examples         in configure step, set -DXO_ENABLE_EXAMPLES=1
  --with-utests           in configure step, set -DENABLE_TESTING=1
  --with-asm              in configure step, set -DXO_ENABLE_ASM=1
  --debug-build           in configure step, set -DCMAKE_BUILD_TYPE=Debug
  --with-opengl=GLFLAG    in configure step, set -DXO_ENABLE_OPENGL=GLFLAG [ON]
  --with-vulkan=VKFLAG    in configure step, set -DXO_ENABLE_VULKAN=VKFLAG [OFF]

  --repo                  report github repo for NAME

  --add-umbrella-remote   (in umbrella sandbox) add remote for xo library NAME
  --split-umbrella-remote (in umbrella sandbox) generate split branch for xo library NAME
  --pull-umbrella-remote  (in umbrella sandbox) pull satellite remote for xo library NAME
  --push-umbrella-remote  (in umbrella sandbox) push satellite remote for xo library NAME

EOF
}

cmd=
noop_flag=0
xoname=
clone_flag=0
configure_flag=0
build_flag=0
build_docs_flag=0
install_flag=0
realclean_flag=0
pathtosource=
pathtobuild=
with_examples=0
with_utests=0
with_asm=0
debug_build=0
with_opengl=
with_vulkan=
repo_flag=0
add_umbrella_remote_flag=0
split_umbrella_remote_flag=0
pull_umbrella_remote_flag=0
push_umbrella_remote_flag=0

while [[ $# > 0 ]]; do
    case "$1" in
        -u | --usage)
            cmd='usage'
            ;;
        -h | --help)
            cmd='help'
            ;;
        -n | --dry-run)
            noop_flag=1
            ;;
        -S)
            shift
            pathtosource=$1
            ;;
        -S=*)
            pathtosource="${1#*=}"
            ;;
        -B)
            shift
            pathtobuild=$1
            ;;
        -B=*)
            pathtobuild="${1#*=}"
            ;;
        --list)
            cmd='list'
            ;;
        --xoname=*)
            xoname="${1#*=}"
            ;;
        --clone)
            clone_flag=1
            ;;
        --configure|--config)
            configure_flag=1
            ;;
        --build)
            build_flag=1
            ;;
        --build-docs)
            build_docs_flag=1
            ;;
        --install)
            install_flag=1
            ;;
        --realclean)
            realclean_flag=1
            ;;
        --with-examples)
            with_examples=1
            ;;
        --with-utests)
            with_utests=1
            ;;
        --with-asm)
            with_asm=1
            ;;
        --debug-build)
            debug_build=1
            ;;
        --with-opengl=*)
            with_opengl="${1#*=}"
            ;;
        --with-vulkan=*)
            with_vulkan="${1#*=}"
            ;;
        --repo)
            repo_flag=1
            ;;
        --add-umbrella-remote)
            add_umbrella_remote_flag=1
            ;;
        --split-umbrella-remote)
            split_umbrella_remote_flag=1
            ;;
        --pull-umbrella-remote)
            pull_umbrella_remote_flag=1
            ;;
        --push-umbrella-remote)
            push_umbrella_remote_flag=1
            ;;
        xo-*)
            xoname="$1"
            ;;
        *)
            usage
            exit 1
            ;;
    esac

    shift
done

#echo xoname=$xoname pathtosource=$pathtosource pathtobuild=$pathtobuild

if [[ -z "$pathtosource" ]]; then
    pathtosource=$xoname
fi

if [[ -z "$pathtobuild" ]]; then
    if [[ -n $xoname ]]; then
        pathtobuild=$xoname/.build
    else
        pathtobuild=.build
    fi
fi

SUBSYSTEMLIST_FILE=@CMAKE_INSTALL_FULL_DATADIR@/etc/xo/subsystem-list

subsystem_list() {
    cat ${SUBSYSTEMLIST_FILE}
}

XO_REPO_STEM=
if [[ $(whoami) == "roland" ]]; then
    XO_REPO_STEM="git@github.com:Rconybea"
else
    XO_REPO_STEM="https://github.com/Rconybea"
fi

printrepo() {
    xoname=$1

    case "$xoname" in
        # carve-outs for 4 snowflake xo repo names
        xo-indentlog)
            echo "${XO_REPO_STEM}/indentlog.git"
            ;;
        xo-refcnt)
            echo "${XO_REPO_STEM}/refcnt.git"
            ;;
        xo-subsys)
            echo "${XO_REPO_STEM}/subsys.git"
            ;;
        xo-reflect)
            echo "${XO_REPO_STEM}/reflect.git"
            ;;
        *)
            if grep -q $1 ${SUBSYSTEMLIST_FILE}; then
                echo "${XO_REPO_STEM}/${1}.git"
            else
                >&2 echo "$0: unknown xo component [${xoname}]"
                return 1
            fi
    esac

    return 0
}

if [[ $cmd == 'usage' ]]; then
    echo -n "usage: "
    usage
    exit 0
elif [[ $cmd == 'help' ]]; then
    echo -n "help; "
    help
    exit 0
fi

set -e

if [[ $cmd == 'list' ]]; then
    subsystem_list
fi

if [[ $repo_flag -eq 1 ]]; then
    if [[ -n "$xoname" ]]; then
        printrepo $xoname
    fi
fi

if [[ $add_umbrella_remote_flag -eq 1 ]]; then
    if [[ $clone_flag -eq 1 || $configure_flag -eq 1 || $build_flag -eq 1 || $build_docs_flag -eq 1 || $install_flag -eq 1 || $realclean_flag -eq 1 ]]; then
        2>&1 echo "error: xo-build: repo operation --add-umbrella-remote conflicts with"
        2>&1 echo "                 build operation --clone|--configure|--build|--build-docs|--install|--realclean"
        exit 1
    fi

    if [[ -n "$xoname" ]]; then
        url=$(printrepo $xoname)

        cmd="git remote add $xoname $url"

        if [[ $noop_flag -eq 1 ]]; then
            echo $cmd
        else
            $cmd
        fi
    fi
fi

if [[ $split_umbrella_remote_flag -eq 1 ]]; then
    if [[ -n "$xoname" ]]; then
        #branch=$(git branch --show-current)
        demux_branch=_demux/$xoname
        cmd="git subtree split --rejoin --prefix=$xoname -b ${demux_branch}"

        if [[ $noop_flag -eq 1 ]]; then
            echo $cmd
        else
            $cmd
        fi
    fi
fi

if [[ $pull_umbrella_remote_flag -eq 1 ]]; then
    if [[ -n "$xoname" ]]; then
        branch=$(git branch --show-current)
        cmd="git subtree pull --rejoin --prefix=$xoname $xoname ${branch}"

        if [[ $noop_flag -eq 1 ]]; then
            echo $cmd
        else
            $cmd
        fi
    fi
fi

if [[ $push_umbrella_remote_flag -eq 1 ]]; then
    if [[ -n "$xoname" ]]; then
        branch=$(git branch --show-current)
        demux_branch=_demux/$xoname
        cmd1="git subtree split --rejoin --prefix=$xoname -b ${demux_branch}"
        remote=${xoname}
        remote_branch=${branch}
        cmd2="git push ${remote} ${demux_branch}:${remote_branch}"
        #cmd="git subtree push --rejoin --prefix=$xoname $xoname ${branch}"

        if [[ $noop_flag -eq 1 ]]; then
            echo $cmd1
            echo $cmd2
        else
            $cmd1
            $cmd2
        fi
    fi
fi

if [[ $clone_flag -eq 1 ]]; then
    if [[ -n "$xoname" ]]; then
        url=$(printrepo $xoname)

        cmd="git clone $url"

        if [[ $noop_flag -eq 1 ]]; then
            echo $cmd
        else
            $cmd
        fi
    fi
fi

if [[ $configure_flag -eq 1 ]]; then
    if [[ -n "$xoname" ]]; then
        testingarg=
        if [[ $with_utests -eq 1 ]]; then
            testingarg="-DENABLE_TESTING=1"
        fi

        asmarg=
        if [[ $with_asm -eq 1 ]]; then
            asmarg="-DENABLE_ASM=1"
        fi

        examplearg=
        if [[ $with_examples -eq 1 ]]; then
            examplearg="-DXO_ENABLE_EXAMPLES=1"
        fi

        cmakebuildtype=
        if [[ $debug_build -eq 1 ]]; then
            cmakebuildtype="-DCMAKE_BUILD_TYPE=Debug"
        fi

        openglarg=
        if [[ -n ${with_opengl} ]]; then
            openglarg="-DXO_ENABLE_OPENGL=${with_opengl}"
        fi

        vulkanarg=
        if [[ -n ${with_vulkan} ]]; then
            vulkanarg="-DXO_ENABLE_VULKAN=${with_vulkan}"
        fi

        cmd="cmake -DCMAKE_INSTALL_PREFIX=@CMAKE_INSTALL_PREFIX@ -DCMAKE_MODULE_PATH=@CMAKE_INSTALL_PREFIX@/share/cmake -S $pathtosource -B $pathtobuild ${testingarg} ${examplearg} ${asmarg} ${openglarg} ${vulkanarg} ${cmakebuildtype}"

        if [[ $noop_flag -eq 1 ]]; then
            echo $cmd
        else
            cwd=$(pwd)
            # write script to re-run cmake later
            rebootcmake=$pathtobuild/rebootcmake

            mkdir -p $(dirname ${rebootcmake})

            cat > ${rebootcmake} <<EOF
#!/usr/bin/env bash

cd ${cwd} && ${cmd}

EOF
            chmod +rx ${rebootcmake}

            $cmd
        fi
    fi
fi

if [[ $build_flag -eq 1 ]]; then
    if [[ -n "$xoname" ]]; then
        cmd="cmake --build $pathtobuild -j"

        if [[ $noop_flag -eq 1 ]]; then
            echo $cmd
        else
            $cmd
        fi
    fi
fi

if [[ $build_docs_flag -eq 1 ]]; then
    if [[ -n "$xoname" ]]; then
        cmd="cmake --build $pathtobuild -- docs"

        if [[ $noop_flag -eq 1 ]]; then
            echo $cmd
        else
            $cmd
        fi
    fi
fi

if [[ $install_flag -eq 1 ]]; then
    if [[ -n "$xoname" ]]; then
        cmd="cmake --install $pathtobuild"

        if [[ $noop_flag -eq 1 ]]; then
            echo $cmd
        else
            $cmd
        fi
    fi
fi

if [[ $realclean_flag -eq 1 ]]; then
    if [[ $noop_flag -eq 1 ]]; then
        echo "rm -rf $pathtobuild"
    else
        rm -rf "${pathtobuild}"
    fi
fi