#!/bin/bash

source ../scripts/setup_env.sh

JSON_CONF=rootfs.json

DEF_USER=`jq -r ".SYS_CONF.DEF_USER" $JSON_CONF`
DEF_PASSWD=`jq -r ".SYS_CONF.DEF_PASSWD" $JSON_CONF`
DEF_HOSTNAME=${BOARD}

TARBALL_DIR=${PRJ_PATH}/../tarballs/

set -e

trap 'exit_handler' EXIT
function exit_handler()
{
    rm -f  ${ROOTFS_DIR}/usr/bin/qemu-arm-static
    umount ${ROOTFS_DIR}/{sys,proc,dev/pts,dev} 2>/dev/null || true
}

function do_debian_fetch()
{
    if [ $SYSTEM != debian -o -d $ROOTFS_DIR ] ; then
        return;
    fi

    debian_src=$1
    ARCH=$2

    # debootstrap fetch debian rootfs
    export DEBIAN_FRONTEND=noninteractive
    export DEBCONF_NONINTERACTIVE_SEEN=true
    export LC_ALL=C
    export LANGUAGE=C
    export LANG=C

    pr_warn "debootstrap fetch start"

    pr_info "debootstrap --arch=${ARCH} --foreign ${DISTRO} ${ROOTFS_DIR} ${debian_src}"
    debootstrap --arch=${ARCH} --foreign ${DISTRO} ${ROOTFS_DIR} ${debian_src}
    chroot ${ROOTFS_DIR} debootstrap/debootstrap --second-stage

    pr_warn "debootstrap fetch done"
    chroot ${ROOTFS_DIR} dpkg --configure -a

    cd ${ROOTFS_DIR}
    tar -cjf ../${ROOTFS_DIR}.orig.tar.bz2 *
    cd -
}

# Install extra apps defined in configure file
function do_debian_apt()
{
    if [ $SYSTEM != debian ] ; then
        return;
    fi

    apt_install=$(eval echo `jq -r .SYS_DEBIAN.INSTALL_APT $JSON_CONF` | tr 'A-Z' 'a-z')
    if [ $apt_install != yes ] ; then
        pr_warn "skip debootstrap apt install extra apps"
        return;
    fi

    pr_warn "debootstrap apt install extra apps"

    extra_apps=`eval jq -r .SYS_DEBIAN.APT_APPS[] $JSON_CONF`

    cp -f /usr/bin/qemu-arm-static ${ROOTFS_DIR}/usr/bin/

    mount -o bind /proc ${ROOTFS_DIR}/proc
    mount -o bind /dev ${ROOTFS_DIR}/dev
    mount -o bind /dev/pts ${ROOTFS_DIR}/dev/pts
    mount -o bind /sys ${ROOTFS_DIR}/sys

    chroot ${ROOTFS_DIR} apt update
    chroot ${ROOTFS_DIR} apt install -y ${extra_apps}
    chroot ${ROOTFS_DIR} apt autoremove

    umount ${ROOTFS_DIR}/{sys,proc,dev/pts,dev}
    pr_warn "debootstrap apt install done"
}

function do_debian_conf()
{
    if [ $SYSTEM != debian ] ; then
        return;
    fi

    pr_warn "update debian system configuration"

    # add default user account
    set +e
    grep "$DEF_USER" ${ROOTFS_DIR}/etc/passwd > /dev/null 2>&1
    if [ $? != 0 ] ; then
        pr_info "setup default user account"
        cp -f /usr/bin/qemu-arm-static ${ROOTFS_DIR}/usr/bin/
        chroot ${ROOTFS_DIR} chmod 4755 /usr/bin/sudo
        chroot ${ROOTFS_DIR} sh -c "useradd -m -s /bin/bash ${DEF_USER}"
        chroot ${ROOTFS_DIR} sh -c "echo ${DEF_USER}:${DEF_PASSWD} | chpasswd"
        chroot ${ROOTFS_DIR} sh -c "usermod -aG video,audio,sudo ${DEF_USER}"
    fi
    set -e

    # modify root password
    chroot ${ROOTFS_DIR} sh -c "echo root:${DEF_PASSWD} | chpasswd"

    # update PATH environment in /etc/profile
    sed -i 's|PATH=.*|PATH="/usr/local/sbin:/usr/local/bin:/usr/sbin:/usr/bin:/sbin:/bin"|g' ${ROOTFS_DIR}/etc/profile

    # update sudo without passwd
    sed -i "s|^%sudo.*|%sudo   ALL=(ALL:ALL) NOPASSWD:ALL|g" ${ROOTFS_DIR}/etc/sudoers

    # enable ping command for all user
    chmod 4755 ${ROOTFS_DIR}/usr/bin/ping*

    # enable root login on serial port
    MOD_FILE=${ROOTFS_DIR}/etc/securetty
    set +e
    grep ttyLP1 ${MOD_FILE} > /dev/null 2>&1
    if [ $? != 0 ] ; then
        echo "" >> ${MOD_FILE}
        echo "# i.MX8ULP serial console" >> ${MOD_FILE}
        echo "ttyLP1" >> ${MOD_FILE}
        echo "ttyLP2" >> ${MOD_FILE}
        echo "ttyLP3" >> ${MOD_FILE}
    fi
    set -e
}


function do_fetch()
{
    if [ -d $ROOTFS_DIR ] ; then
        pr_warn "rootfs tree for $SYSTEM($DISTRO) fetch already"
        return;
    fi

    pr_warn "start fetch rootfs tree for $SYSTEM($DISTRO) "

    if [ -f $ROOTFS_DIR.tar.bz2 ] ; then
        do_unpack $TARBALL_DIR/$ROOTFS_DIR.tar.bz2 $ROOTFS_DIR
        return;
    fi

    if [ $SYSTEM == "yocto" ] ; then

        mkdir -p $ROOTFS_DIR
        do_fetch_json  $JSON_CONF SYS_YOCTO $ROOTFS_DIR
        do_unpack $TARBALL_DIR/$ROOTFS_DIR.tar.bz2 $ROOTFS_DIR

    elif [ $SYSTEM == "buildroot" ] ; then

        mkdir -p $ROOTFS_DIR
        do_fetch_json  $JSON_CONF SYS_BUILDROOT $ROOTFS_DIR
        do_unpack $TARBALL_DIR/$ROOTFS_DIR.tar.bz2 $ROOTFS_DIR

    elif [ $SYSTEM == "debian" ] ; then
        protocal=`jq -r ".SYS_DEBIAN.PROTOCAL" $JSON_CONF`
        if [ $protocal != "debootstrap" ] ; then
            mkdir -p $ROOTFS_DIR
            do_fetch_json $JSON_CONF SYS_DEBIAN $ROOTFS_DIR
            do_unpack $TARBALL_DIR/$ROOTFS_DIR.tar.bz2 $ROOTFS_DIR

        else
            debian_src=`jq -r ".SYS_DEBIAN.URL" $JSON_CONF`
            arch=`jq -r ".SYS_DEBIAN.ARCH" $JSON_CONF`
            do_debian_fetch $debian_src $arch
        fi

    fi
    rm -f *.tar.*
}


function do_install()
{
    # Remove lib/modules first
    rm -rf $ROOTFS_DIR/lib/modules/*

    # apt install extra packet for debian rootfs
    if [ $SYSTEM == "debian" ] ; then
        do_debian_apt
        do_debian_conf
        do_install_json $JSON_CONF SYS_DEBIAN.INSTALL_FILES
    elif [ $SYSTEM == "yocto" ] ; then
        do_install_json $JSON_CONF SYS_YOCTO.INSTALL_FILES
    elif [ $SYSTEM == "buildroot" ] ; then
        do_install_json $JSON_CONF SYS_BUILDROOT.INSTALL_FILES
    fi
}

function do_config()
{
    pr_warn "start configure for $SYSTEM($DISTRO) rootfs"

    set +e

    # update hostnmae and issue
    echo "Welcome to ${BOARD} Board GNU/Linux ${SYSTEM}(${DISTRO}) system, default password '$DEF_PASSWD'." > ${ROOTFS_DIR}/etc/issue
    echo $DEF_HOSTNAME > ${ROOTFS_DIR}/etc/hostname
    grep "${DEF_HOSTNAME}" ${ROOTFS_DIR}/etc/hosts > /dev/null 2>&1
    if [ $? != 0 ] ; then
       echo "127.0.0.1       ${DEF_HOSTNAME}" >> ${ROOTFS_DIR}/etc/hosts
    fi

    # update dns server
    echo "nameserver 114.114.114.114" > ${ROOTFS_DIR}/etc/resolv.conf
    echo "nameserver 223.5.5.5" >> ${ROOTFS_DIR}/etc/resolv.conf

    # update profile
    sed -i "s|PS1='# '|PS1='\\\u@\\\h:\\\w# '|g" ${ROOTFS_DIR}/etc/profile
    sed -i "s|PS1='$ '|PS1='\\\u@\\\h:\\\w$ '|g" ${ROOTFS_DIR}/etc/profile

    # add ls alias for display with color
    grep "^alias ls=" ${ROOTFS_DIR}/etc/profile > /dev/null 2>&1
    if [ $? != 0 ] ; then
       echo "alias ls='ls --color=auto'" >> ${ROOTFS_DIR}/etc/profile
    fi

    # permit root ssh login
    if [ -f ${ROOTFS_DIR}/etc/ssh/sshd_config ] ; then
        sed -i "s|^#PermitRootLogin.*|PermitRootLogin yes|g" ${ROOTFS_DIR}/etc/ssh/sshd_config
        sed -i "s|^#PasswordAuthentication.*|PasswordAuthentication yes|g" ${ROOTFS_DIR}/etc/ssh/sshd_config
    fi

    set -e
    pr_warn "configure for $SYSTEM($DISTRO) rootfs done"
}

function do_pack()
{
    pr_warn "start generate $SYSTEM($DISTRO) rootfs packet"

    cd ${ROOTFS_DIR}
    tar -cjf ../${ROOTFS_DIR}.tar.bz2 *
    cd ${PRJ_PATH}

    pr_warn "generate $SYSTEM($DISTRO) rootfs packet done"
}

function do_distclean()
{
    pr_warn "clean rootfs source tree"

    rm -rf $ROOTFS_DIR* rootfs_*

    exit;
}

function do_rootfs()
{
    do_fetch
    do_install
    do_config
}

function do_root()
{
    echo ""
    if [[ $1 == "yes" ]] && [ `id -u` != 0 ] ; then
        echo "ERROR: This action must run as root!"
        echo ""
        exit;
    elif [[ $1 != "yes" ]] && [ `id -u` == 0 ] ; then
        echo "ERROR: This action cannot run as root!"
        echo ""
        exit;
    fi
}

function do_usage()
{
    echo ""
    echo "Usage:"
    echo "   $0 [-b] [p] [-c] [-h]"
    echo "       -b: download and build $PRJ_NAME"
    echo "       -p: packet the rootfs tree source"
    echo "       -c: clean all the source code"
    echo "       -h: show this help message"
    echo ""
    echo " WARNNING: This shell script must run as sudo"
    echo ""
    exit;
}

while getopts "bpch" OPTNAME
do
    case "${OPTNAME}" in
        "b")
            break;
            ;;

        "p")
            do_pack
            ;;

        "c")
            do_root "yes"
            do_distclean
            ;;

        "h")
            do_usage
            ;;
    esac
done

do_root "yes"
do_rootfs