#!/usr/bin/env bash
#
# Copyright 2022 Bryan C. Roessler
#
# Build and flash/upgrade OpenWRT devices
#
# Apache 2.0 License

# Set default release
: "${RELEASE:="22.03.2"}"

printHelp() {
    debug "${FUNCNAME[0]}"

    cat <<-'EOF'
Run and deploy OpenWRT images using the Image Builder.

USAGE:
openwrtbuilder [OPTION [VALUE]]...

OPTIONS
    --profile, -p PROFILE
    --info, -i PROFILE
    --list-profiles, -l
    --release, -r, --version, -v RELEASE_VERSION ("snapshot", "22.03.3", etc.)
    --builddir, -b PATH
    --ssh-upgrade HOST
        Example: root@192.168.1.1
    --ssh-backup SSH_PATH
        (Enabled by default for --ssh-upgrade)
    --flash, -f DEVICE
        Example: /dev/sdX
    --reset
        Cleanup all source and output files
    --debug, -d
    --help, -h
EOF
}


readInput() {
    debug "${FUNCNAME[0]}"

    unset RESET

    if _input=$(getopt -o +r:v:p:i:lb:f:dh -l release:,version:,profile:,info:,list-profiles,builddir:,ssh-upgrade:,ssh-backup:,flash:,reset,debug,help -- "$@"); then
        eval set -- "$_input"
        while true; do
            case "$1" in
                --release|-r|--version|-v)
                    shift && RELEASE="$1"
                    ;;
                --profile|-p)
                    shift && PROFILE="$1"
                    ;;
                --info|-i)
                    shift && PROFILE="$1" && PROFILE_INFO=1 && exit $?
                    ;;
                --list-profiles|-l)
                    listProfiles && exit $?
                    ;;
                --builddir|-b)
                    shift && BUILDDIR="$1"
                    ;;
                --ssh-upgrade)
                    shift && SSH_UPGRADE_PATH="$1"
                    ;;
                --ssh-backup)
                    shift && SSH_BACKUP_PATH="$1"
                    ;;
                --flash|-f)
                    shift && FLASH_DEV="$1"
                    ;;
                --reset)
                    RESET=1
                    ;;
                --debug|-d)
                    echo "Debugging on"
                    DEBUG=1
                    ;;
                --help|-h)
                    printHelp && exit 0
                    ;;
                --)
                    shift
                    break
                    ;;
            esac
            shift
        done
    else
        echo "Incorrect options provided"
        printHelp && exit 1
    fi
}


listProfiles() {
    debug "${FUNCNAME[0]}"
    grep "declare -Ag" "$PFILE" | cut -d" " -f3
}


installHostDependencies() {
    debug "${FUNCNAME[0]}"

    local -a _pkg_list
    local _pkg_cmd

    source /etc/os-release

    if [[ "$ID" =~ ^(fedora)$ ]]; then
        _pkg_list=(\
            "@c-development" \
            "@development-tools" \
            "@development-libs" \
            "perl-FindBin" \
            "zlib-static" \
            "elfutils-libelf-devel" \
            "gawk" \
            "unzip" \
            "file" \
            "wget" \
            "python3" \
            "python2" \
            "axel" \
        )
        _pkg_cmd="dnf"
    elif [[ "$ID" =~ ^(debian|ubuntu)$ ]]; then
        _pkg_list=(\
            "build-essential" \
            "libncurses5-dev" \
            "libncursesw5-dev" \
            "zlib1g-dev" \
            "gawk" \
            "git" \
            "gettext" \
            "libssl-dev" \
            "xsltproc" \
            "wget" \
            "unzip" \
            "python" \
            "axel" \
        )
        _pkg_cmd="apt-get"
    fi

    debug "Installing dependencies"
    debug "sudo $_pkg_cmd -y install ${_pkg_list[*]}"
    if ! sudo "$_pkg_cmd" -y install "${_pkg_list[@]}" > /dev/null 2>&1; then
        echo "Warning: Problem installing dependencies"
        return 1
    fi
}


getImageBuilder() {
    debug "${FUNCNAME[0]}"

    local _url _filename _dl_tool

    if [[ "${P_ARR[release]}" == "snapshot" ]]; then
        _filename="openwrt-imagebuilder-${P_ARR[target]//\//-}.Linux-x86_64.tar.xz"
        _url="https://downloads.openwrt.org/snapshots/targets/${P_ARR[target]}/$_filename"
        if [[ -f "${P_ARR[source_archive]}" ]]; then
            if askOk "Update ImageBuilder snapshot?"; then
                rm -f "${P_ARR[source_archive]}"
            else
                return 0
            fi
        fi
    else
        _filename="openwrt-imagebuilder-${P_ARR[release]}-${P_ARR[target]//\//-}.Linux-x86_64.tar.xz"
        _url="https://downloads.openwrt.org/releases/${P_ARR[release]}/targets/${P_ARR[target]}/$_filename"
        [[ -f "${P_ARR[source_archive]}" ]] && return 0 # Reuse existing ImageBuilders
    fi
    
    # Make sources directory if it does not exist
    [[ ! -d "$BUILDDIR/sources" ]] && mkdir -p "$BUILDDIR/sources"

    if hash axel &>/dev/null; then
        _dl_tool="axel"
    elif hash curl &>/dev/null; then
        _dl_tool="curl"
    else
        echo "Downloading the ImageBuilder requires axel or curl!"
        return 1
    fi

    #_dl_tool="curl" # TODO remove
    
    echo "Downloading imagebuilder archive using $_dl_tool"

    debug "$_dl_tool -o ${P_ARR[source_archive]} $_url"
    if ! "$_dl_tool" -o "${P_ARR[source_archive]}" "$_url"; then
        echo "Could not download imagebuilder archive"
        exit 1
    fi

    if [[ ! -f "${P_ARR[source_archive]}" ]]; then
        echo "Archive missing"
        exit 1
    fi

    echo "Extracting image archive"
    [[ ! -d "${P_ARR[source_dir]}" ]] && mkdir -p "${P_ARR[source_dir]}"
    debug "tar -xf ${P_ARR[source_archive]} -C ${P_ARR[source_dir]} --strip-components 1"
    if ! tar -xf "${P_ARR[source_archive]}" -C "${P_ARR[source_dir]}" --strip-components 1; then
        echo "Extraction failed"
        exit 1
    fi
}


addRepos() {
    debug "${FUNCNAME[0]}"

    if [[ -v P_ARR[repo] ]]; then
        if ! grep -q "${P_ARR[repo]}" "${P_ARR[source_dir]}/repositories.conf"; then
            echo "${P_ARR[repo]}" >> "${P_ARR[source_dir]}/repositories.conf"
        fi
        sed -i '/option check_signature/d' "${P_ARR[source_dir]}/repositories.conf"
    fi
}


sshBackup() {
    debug "${FUNCNAME[0]}"

    local _date _hostname _backup_fname

    [[ -d "$FILESDIR" ]] || mkdir -p "$FILESDIR"

    printf -v _date '%(%Y-%m-%d-%H-%M-%S)T'
    _hostname=$(ssh -qt "$SSH_BACKUP_PATH" echo -n \$HOSTNAME)
    _backup_fname="backup-$_hostname-$_date.tar.gz"

    # Make backup archive on remote
    debug "ssh -t $SSH_BACKUP_PATH sysupgrade -b /tmp/$_backup_fname"
    if ! ssh -t "$SSH_BACKUP_PATH" "sysupgrade -b /tmp/$_backup_fname"; then
        echo "SSH backup failed"
        exit 1
    fi

    # Move backup archive locally
    debug "rsync -avz --remove-source-files $SSH_BACKUP_PATH:/tmp/$_backup_fname $BUILDDIR/"
    if ! rsync -avz --remove-source-files "$SSH_BACKUP_PATH":"/tmp/$_backup_fname" "$BUILDDIR/"; then
        echo "Could not copy SSH backup"
        exit 1
    fi

    # Extract backup archive
    debug "tar -C $FILESDIR -xzf $BUILDDIR/$_backup_fname"
    if ! tar -C "$FILESDIR" -xzf "$BUILDDIR/$_backup_fname"; then
        echo "Could not extract SSH backup"
        exit 1
    fi

    rm "$BUILDDIR/$_backup_fname"
}


makeImage() {
    debug "${FUNCNAME[0]}"

    # Reuse the existing output
    if [[ -d "${P_ARR[out_bin_dir]}" ]]; then
        if askOk "${P_ARR[out_bin_dir]} exists. Rebuild?"; then
            rm -rf "${P_ARR[out_bin_dir]}"
        else
            return 0
        fi
    fi

    [[ ! -d "${P_ARR[out_bin_dir]}" ]] && mkdir -p "${P_ARR[out_bin_dir]}"

    if ! make image \
            BIN_DIR="${P_ARR[out_bin_dir]}" \
            PROFILE="${P_ARR[profile]}" \
            PACKAGES="${P_ARR[packages]}" \
            FILES="$FILESDIR" \
            --directory="${P_ARR[source_dir]}" \
            --jobs=$(( $(nproc) - 1 )) \
            > make.log; then
        echo "Make image failed!"
        exit 1
    fi
}


flashImage() {
    debug "${FUNCNAME[0]}"

    local _umount

    if [[ ! -e "$FLASH_DEV" ]]; then
        echo "The device specified by --flash could not be found"
        exit 1
    fi

    # TODO Roughly chooses the correct image
    if [[ -f "${P_ARR[factory_img_gz]}" ]]; then
        img_gz="${P_ARR[factory_img_gz]}"
        img="${P_ARR[factory_img]}"
    elif [[ -f "${P_ARR[sysupgrade_img_gz]}" ]]; then
        img_gz="${P_ARR[sysupgrade_img_gz]}"
        img="${P_ARR[sysupgrade_img]}"
    else
        return 1
    fi

    debug "$img_gz $img"

    debug "gunzip -qfk $img_gz"
    gunzip -qfk "$img_gz"
        
    echo "Unmounting target device $FLASH_DEV partitions"
    _umount=( "$FLASH_DEV"?* )
    debug "umount ${_umount[*]}"
    sudo umount "${_umount[@]}"

    debug "sudo dd if=\"$img\" of=\"$FLASH_DEV\" bs=2M conv=fsync"
    if sudo dd if="$img" of="$FLASH_DEV" bs=2M conv=fsync; then
        sync
        echo "Image flashed sucessfully!"
    else
        echo "dd failed!"
        exit 1
    fi
}


sshUpgrade() {
    debug "${FUNCNAME[0]}"

    echo "Copying \"${P_ARR[sysupgrade_bin_gz]}\" to $SSH_UPGRADE_PATH/tmp/"
    debug "scp \"${P_ARR[sysupgrade_bin_gz]}\" \"$SSH_UPGRADE_PATH\":\"/tmp/${P_ARR[sysupgrade_bin_gz_fname]}\""
    # shellcheck disable=SC2140
    if ! scp "${P_ARR[sysupgrade_bin_gz]}" "$SSH_UPGRADE_PATH":"/tmp/${P_ARR[sysupgrade_bin_gz_fname]}"; then
        echo "Could not access the --ssh-upgrade PATH"
        exit 1
    fi

    echo "Executing remote sysupgrade"
    debug "ssh \"$SSH_UPGRADE_PATH\" \"sysupgrade -F /tmp/${P_ARR[sysupgrade_bin_gz_fname]}\""
    # shellcheck disable=SC2029
    ssh "$SSH_UPGRADE_PATH" "sysupgrade -F /tmp/${P_ARR[sysupgrade_bin_gz_fname]}"
}


debug() { (( DEBUG )) && echo "Running: $*"; }


askOk() {
    local _response
    read -r -p "$* [y/N]" _response
    _response=${_response,,}
    [[ ! "$_response" =~ ^(yes|y)$ ]] && return 1
    return 0
}


reset() {
    debug "${FUNCNAME[0]}"
    askOk "Remove $FILESDIR $BUILDDIR/sources $BUILDDIR/bin?" || exit $?
    debug "rm -rf $FILESDIR $BUILDDIR/sources $BUILDDIR/bin"
    rm -rf "$FILESDIR" "${BUILDDIR:?}/sources" "${BUILDDIR:?}/bin"
}


loadProfiles() {
    debug "${FUNCNAME[0]}"
    declare -g SCRIPTDIR PFILE
    # https://stackoverflow.com/a/4774063
    SCRIPTDIR="$( cd -- "$(dirname "$0")" >/dev/null 2>&1 || exit $? ; pwd -P )"
    PFILE="$SCRIPTDIR/profiles"
    # shellcheck source=./profiles
    ! source "$PFILE" && echo "profiles file missing!" && return 1
}


main() {
    debug "${FUNCNAME[0]}"

    loadProfiles
   
    readInput "$@"

    [[ ! ${!PROFILE@a} = A ]] && echo "Profile does not exist" && return 1
    declare -gn P_ARR="$PROFILE"
    declare _out_prefix

    : "${BUILDDIR:=$SCRIPTDIR}"
    : "${FILESDIR:=$BUILDDIR/files}"

    : "${P_ARR[release]:=$RELEASE}"
    : "${P_ARR[source_archive]:=$BUILDDIR/sources/${P_ARR[profile]}-${P_ARR[release]}.tar.xz}"
    : "${P_ARR[source_dir]:=${P_ARR[source_archive]%.tar.xz}}"
    : "${P_ARR[out_bin_dir]:=$BUILDDIR/bin/${P_ARR[profile]}-${P_ARR[release]}}"

    if [[ "${P_ARR[release]}" == "snapshot" ]]; then
        _out_prefix="${P_ARR[out_bin_dir]}/openwrt-${P_ARR[target]//\//-}-${P_ARR[profile]}"
    else
        _out_prefix="${P_ARR[out_bin_dir]}/openwrt-${P_ARR[release]}-${P_ARR[target]//\//-}-${P_ARR[profile]}"
    fi

    : "${P_ARR[factory_img]:=$_out_prefix-${P_ARR[filesystem]}-factory.img}"
    : "${P_ARR[factory_img_gz]:=${P_ARR[factory_img]}.gz}"
    : "${P_ARR[sysupgrade_img]:=$_out_prefix-${P_ARR[filesystem]}-sysupgrade.img}"
    : "${P_ARR[sysupgrade_img_gz]:=${P_ARR[sysupgrade_img]}.gz}"
    : "${P_ARR[sysupgrade_bin]:=$_out_prefix-${P_ARR[filesystem]}-sysupgrade.img}"
    : "${P_ARR[sysupgrade_bin_fname]:=${P_ARR[sysupgrade_bin]##*/}}"
    : "${P_ARR[sysupgrade_bin_gz]:=${P_ARR[sysupgrade_bin]}.gz}"
    : "${P_ARR[sysupgrade_bin_gz_fname]:=${P_ARR[sysupgrade_bin_gz]##*/}}"

    (( RESET )) && reset

    if (( DEBUG )) || (( PROFILE_INFO )); then
        for x in "${!P_ARR[@]}"; do printf "[%s]=%s\n" "$x" "${P_ARR[$x]}"; done
    fi

    installHostDependencies

    getImageBuilder

    addRepos

    #copyFiles

    [[ -v SSH_BACKUP_PATH ]] && sshBackup
    if makeImage; then
        [[ -v SSH_UPGRADE_PATH ]] && sshUpgrade
        [[ -v FLASH_DEV ]] && flashImage
    fi
}

main "$@"
exit