#!/bin/bash

# this project absolute path
PRJ_PATH=$(cd $(dirname "${BASH_SOURCE[0]}") && pwd)

# top project absolute path
TOP_PATH=$(realpath $PRJ_PATH/..)

# binaries install path
INST_PATH=$PRJ_PATH/install

# download taballs path
TARBALL_PATH=$PRJ_PATH/tarballs

# config file path
CONF_FILE=$TOP_PATH/config.json

# shell script will exit once get command error
set -e

#+-------------------------+
#| Shell script functions  |
#+-------------------------+

function pr_error() {
    echo -e "\033[40;31m $1 \033[0m"
}

function pr_warn() {
    echo -e "\033[40;33m $1 \033[0m"
}

function pr_info() {
    echo -e "\033[40;32m $1 \033[0m"
}

# decompress a packet to destination path
function do_unpack()
{
    tarball=$1
    dstpath=`pwd`

    if [[ $# == 2 ]] ; then
        dstpath=$2
    fi

    pr_info "decompress $tarball => $dstpath"

    mkdir -p $dstpath
    case $tarball in
        *.tar.gz)
            tar -xzf $tarball -C $dstpath
            ;;

        *.tar.bz2)
            tar -xjf $tarball -C $dstpath
            ;;

        *.tar.xz)
            tar -xJf $tarball -C $dstpath
            ;;

        *.tar.zst)
            tar -I zstd -xf $tarball -C $dstpath
            ;;

        *.tar)
            tar -xf $tarball -C $dstpath
            ;;

        *.zip)
            unzip -qo $tarball -d $dstpath
            ;;

        *)
            pr_error "decompress Unsupport packet: $tarball"
            return 1;
            ;;
    esac
}

# parser configure file and export environment variable
function export_env()
{
    export BOARD=`jq -r ".bsp.board" $CONF_FILE | tr 'A-Z' 'a-z'`
    export BSPVER=`jq -r ".bsp.version" $CONF_FILE | tr 'A-Z' 'a-z'`
    export URL=`jq -r ".bsp.download" $CONF_FILE | tr 'A-Z' 'a-z'`
    export DISTRO=`jq -r ".system.distro" $CONF_FILE | tr 'A-Z' 'a-z'`
    export DISVER=`jq -r ".system.version" $CONF_FILE | tr 'A-Z' 'a-z'`
    export IMAGE_SIZE=`jq -r ".system.imgsize" $CONF_FILE | tr 'A-Z' 'a-z'`
    export BOOT_SIZE=`jq -r ".system.bootsize" $CONF_FILE | tr 'A-Z' 'a-z'`

    export ROOTFS=rootfs-${DISTRO}-${DISVER}
    export IMAGE_NAME=$DISTRO-$DISVER-$BSPVER.img


    # i.MX6ULL only need build uboot-imx
    if [[ $BOARD =~ 6ull ]] ; then

        # u-boot will be deployed in 2nd sector on eMMC/TFCard
        export UBOOT_SECTOR=2

    # i.MX8MP need build atf and u-boot
    elif [[ $BOARD =~ 8mp ]] ; then

        # u-boot will be deployed in 64th sector on eMMC/TFCard
        export UBOOT_SECTOR=64

    fi
}

function do_fetch()
{
    cd $PRJ_PATH

    SRCS=$ROOTFS
    SUFIX=tar.xz

    if [ -d $ROOTFS/bin ] ; then
        pr_info "$ROOTFS fetched already"
        return ;
    fi

    if [ $DISTRO == yocto ] ; then
        if [[ $YCT_VER != hardknott && $YCT_VER != honister ]] ; then
            SUFIX=tar.zst
        fi
    fi

    # Download source code packet
    if [ ! -s $TARBALL_PATH/$ROOTFS.$SUFIX ] ; then
        pr_info "start fetch $ROOTFS source code"
        mkdir -p $TARBALL_PATH
        wget $URL/$BOARD/rootfs/$ROOTFS.$SUFIX -P $TARBALL_PATH
    fi

    # decompress source code packet
    mkdir -p $ROOTFS
    do_unpack $TARBALL_PATH/$ROOTFS.$SUFIX $ROOTFS
}

# System image layout map:
# +-------------------+--------------------+----------------------+
# | Raw Part(10MB)    | FAT32 Part2(100MB) | EXT4 Part3(All left) |
# +-------------------+--------------------+----------------------+
# | U-boot on #2/#64  |   Kernel and DTB   |   Root file system   |
# +-------------------+--------------------+----------------------+

function build_image()
{
    UBOOT_SIZE=10
    UBOOT_BINPATH=$TOP_PATH/bootloader/install/
    KERNEL_BINPATH=$TOP_PATH/kernel/install/

    export LOOP_DEV=`losetup  -f | cut -d/ -f3`
    export MNT_POINT=$PRJ_PATH/mnt


    pr_warn "Build $DISTRO-$DISVER system image"

    pr_info "start generate empty system image"
    dd if=/dev/zero of=${IMAGE_NAME} bs=1024k count=${IMAGE_SIZE} conv=sync
    chmod a+x ${IMAGE_NAME}

    pr_info "start partition system image"
    fat_start=$UBOOT_SIZE
    fat_end=`expr $UBOOT_SIZE + $BOOT_SIZE`
    parted ${IMAGE_NAME} mklabel msdos
    parted ${IMAGE_NAME} mkpart primary fat32 ${fat_start}M ${fat_end}M
    parted ${IMAGE_NAME} mkpart primary ext4 ${fat_end}M 100%
    sync

    pr_info "losetup system image on $LOOP_DEV"
    losetup /dev/${LOOP_DEV}  ${IMAGE_NAME}
    kpartx -av /dev/${LOOP_DEV}

    pr_info "start format system image"
    mkfs.vfat /dev/mapper/${LOOP_DEV}p1
    mkfs.ext4 /dev/mapper/${LOOP_DEV}p2
    sync

    pr_info "start install u-boot image"
    dd if=$UBOOT_BINPATH/u-boot-${BOARD}.imx of=${IMAGE_NAME} bs=512 seek=66 conv=notrunc,sync

    pr_info "start install linux kernel images"
    mkdir -p $MNT_POINT

    mount -t vfat /dev/mapper/${LOOP_DEV}p1 ${MNT_POINT}
    cp -rf $KERNEL_BINPATH/zImage       ${MNT_POINT}/
    cp -rf $KERNEL_BINPATH/${BOARD}.dtb ${MNT_POINT}/
    cp -rf $KERNEL_BINPATH/overlays/    ${MNT_POINT}/
    cp -rf files/config-${BOARD}.txt    ${MNT_POINT}/config.txt
    sync && umount ${MNT_POINT}

    pr_info "update drivers in root filesystem"
    rm -rf $ROOTFS/lib/modules/
    mkdir -p $ROOTFS/lib/modules/
    cp -rf $KERNEL_BINPATH/lib/* $ROOTFS/lib/

    pr_info "start install root filesystem"
    mount -t ext4 /dev/mapper/${LOOP_DEV}p2 ${MNT_POINT}
    cp -af $ROOTFS/*                    ${MNT_POINT}
    cp -rf files/pinctrl-${BOARD}       ${MNT_POINT}/usr/sbin/pinctrl
    cp -rf files/pinloop                ${MNT_POINT}/usr/sbin/
    cp -rf files/expand_rootfs          ${MNT_POINT}/usr/sbin/
    chmod +x ${MNT_POINT}/usr/sbin/pinctrl
    chmod +x ${MNT_POINT}/usr/sbin/pinloop
    chmod +x ${MNT_POINT}/usr/sbin/expand_rootfs
    sync && umount ${MNT_POINT}

    pr_warn "Build $DISTRO-$DISVER system image down"
}

function exit_handler()
{
    pr_warn "Shell script exit now, do some clean work\n"
    set +e

    if mountpoint ${MNT_POINT} > /dev/null 2>&1 ; then
        pr_info "umount ${MNT_POINT}"
        umount ${MNT_POINT} > /dev/null 2>&1
    fi

    rm -rf ${MNT_POINT}

    if [ -z ${LOOP_DEV} ] ; then
        return ;
    fi

    if [ -e /dev/mapper/${LOOP_DEV}p1 ] ; then
        pr_info "kpartx -dv /dev/${LOOP_DEV}"
        kpartx -dv /dev/${LOOP_DEV}
    fi

    losetup -a | grep "${LOOP_DEV}" > /dev/null 2>&1
    if [ $? == 0 ]  ; then
        pr_info "losetup -d /dev/${LOOP_DEV}"
        losetup -d /dev/${LOOP_DEV}
    fi
}

function do_build()
{
    cd $PRJ_PATH

    build_image
}

function do_install()
{
    cd $PRJ_PATH

    mkdir -p $INST_PATH
    cp $UBOOT_BINPATH/u-boot-${BOARD}.imx $INST_PATH
    mv $IMAGE_NAME $INST_PATH

    cd $INST_PATH

    pr_info "\ncompress system images $IMAGE_NAME"
    bzip2 $IMAGE_NAME

    pr_info "\nsystem images installed to '$INST_PATH'"
    ls && echo ""
}

function do_clean()
{
    for d in rootfs-*
    do
        rm -rf $PRJ_PATH/$d
    done

    rm -rf $INST_PATH
    rm -f *.img
    rm -rf $TARBALL_PATH
}

#+-------------------------+
#| Shell script body entry |
#+-------------------------+

if [ `id -u` != 0 ] ; then
    pr_error "ERROR: This shell script must run as root"
    exit;
fi

cd $PRJ_PATH

export_env

if [[ $# == 1 && $1 == -c ]] ;then
    pr_warn "start clean system image"
    do_clean
    exit;
fi

pr_warn "start build $DISTRO-$DISVER for ${BOARD}"

trap 'exit_handler' EXIT

do_fetch

do_build

do_install