#!/bin/bash

set -eu
set -o pipefail

# Collect configuration
# ---------------------

# Development options
DIB_UPDATE_REQUESTED=${DIB_UPDATE_REQUESTED:-true}
USE_OFFLINE_MODE=${USE_OFFLINE_MODE:-"yes"}
ENABLE_DEBUG_MODE=${ENABLE_DEBUG_MODE:-"no"}
DISABLE_IMG_COMPRESSION=${DISABLE_IMG_COMPRESSION:-"no"}

# Manila user settings
MANILA_USER=${MANILA_USER:-"manila"}
MANILA_PASSWORD=${MANILA_PASSWORD-"manila"}
MANILA_USER_AUTHORIZED_KEYS=${MANILA_USER_AUTHORIZED_KEYS:-"None"}

# Manila image settings
MANILA_IMG_ARCH=${MANILA_IMG_ARCH:-"amd64"}
MANILA_IMG_OS=${MANILA_IMG_OS:-"manila-ubuntu-minimal"}
MANILA_IMG_OS_VER=${MANILA_IMG_OS_VER:-"jammy"}
MANILA_IMG_NAME=${MANILA_IMG_NAME:-"manila-service-image"}

# Manila image creation default
MANILA_SHARE_PROTO=${MANILA_SHARE_PROTO:-"default"}
MANILA_DISTRO=${MANILA_DISTRO:-"ubuntu"}

#Misc settings
DHCP_TIMEOUT=${DHCP_TIMEOUT:-"300"}

# Path to elements
SCRIPT_HOME="$( cd "$( dirname "${BASH_SOURCE[0]}" )" && pwd )"

if [ -d $SCRIPT_HOME/../share/manila-elements ]; then
    _PREFIX=$SCRIPT_HOME/../share/manila-elements
elif [ -d $SCRIPT_HOME/../../../elements ]; then
    _PREFIX=$SCRIPT_HOME/../../..
else
    _PREFIX=$SCRIPT_HOME/..
fi
export ELEMENTS_PATH=$_PREFIX/elements

# diskimage-builder general settings
export DIB_DEFAULT_INSTALLTYPE=package
export DIB_RELEASE=$MANILA_IMG_OS_VER

# diskimage-builder user settings
export DIB_MANILA_USER_USERNAME=$MANILA_USER
export DIB_MANILA_USER_PASSWORD=$MANILA_PASSWORD
export DIB_MANILA_USER_AUTHORIZED_KEYS=$MANILA_USER_AUTHORIZED_KEYS
export DIB_DHCP_TIMEOUT=$DHCP_TIMEOUT

# CLI
# ---
err() {
    echo -e "${0##*/}: $@" >&2
}

print_usage() {
    echo "Usage: ${0##*/} [-s share-proto] [-d distro] [-h]"
    echo "Options:"
    echo " -s | --share-proto: name of the share protocol. \
         Possible options are nfs, nfs-ganesha, cephfs, cifs or zfs"
    echo " -d | --distro: name of the Linux distro. \
         Possible options are ubuntu or centos"
    echo " -h | --help: print this usage message and exit"
    echo ""
    echo "Usage example: manila_image_elements -s nfs"
}

valid_share_protocol() {
    if [ "${MANILA_SHARE_PROTO}" != "nfs" ] && [ "${MANILA_SHARE_PROTO}" != "nfs-ganesha" ] &&
       [ "${MANILA_SHARE_PROTO}" != "cifs" ] && [ "${MANILA_SHARE_PROTO}" != "zfs" ] &&
       [ "${MANILA_SHARE_PROTO}" != "cephfs" ]; then
        err "Protocol ${MANILA_SHARE_PROTO} not supported. Valid options are nfs, nfs-ganesha, cephfs, cifs or zfs."
        exit 1
    fi
}

valid_distro() {
    if ["${MANILA_DISTRO}" != "ubuntu" ] && [ "${MANILA_DISTRO}" != "centos" ]; then
        err "Distro ${MANILA_DISTRO} not supported. Valid options are ubuntu or centos."
        exit 1
    fi
}

parse_arguments() {
    while [[ $# > 0 ]]; do
        case "$1" in
            -s|--share)
                export MANILA_SHARE_PROTO=$2
                valid_share_protocol
                shift 2
            ;;
            -d|--distro)
                export MANILA_DISTRO=$2
                export MANILA_IMG_OS=manila-$2-minimal
                valid_distro
                shift 2
            ;;
            -h|--help)
                print_usage
                exit 0
            ;;
            *)
                err "Error: Unknown option: $1."
                exit 1
            ;;
         esac
    done
}

# Verify configuration
# --------------------
configure() {
    REQUIRED_ELEMENTS="manila-ssh vm $MANILA_IMG_OS dhcp-all-interfaces"
    IMAGE_FORMAT="qcow2"
    OPTIONAL_ELEMENTS=
    OPTIONAL_DIB_ARGS=

    if [ "$MANILA_SHARE_PROTO" = "default" ]; then
        # NOTE(vkmc) Generic driver uses 2 protocols by default
        # NFS and CIFS. This is required by the gate.
        OPTIONAL_ELEMENTS="$OPTIONAL_ELEMENTS ${MANILA_DISTRO}-nfs ${MANILA_DISTRO}-cifs"
    elif [ "$MANILA_SHARE_PROTO" = "nfs" ]; then
        OPTIONAL_ELEMENTS="$OPTIONAL_ELEMENTS ${MANILA_DISTRO}-nfs"
    elif [ "$MANILA_SHARE_PROTO" = "nfs-ganesha" ]; then
        OPTIONAL_ELEMENTS="$OPTIONAL_ELEMENTS ${MANILA_DISTRO}-nfs-ganesha"
    elif [ "$MANILA_SHARE_PROTO" = "cifs" ]; then
        OPTIONAL_ELEMENTS="$OPTIONAL_ELEMENTS ${MANILA_DISTRO}-cifs"
    elif [ "$MANILA_SHARE_PROTO" = "zfs" ]; then
        OPTIONAL_ELEMENTS="$OPTIONAL_ELEMENTS ${MANILA_DISTRO}-zfs"
    elif [ "$MANILA_SHARE_PROTO" = "cephfs" ]; then
        OPTIONAL_ELEMENTS="$OPTIONAL_ELEMENTS cephfs"
    fi

    if [ "$USE_OFFLINE_MODE" = "yes" ]; then
        OPTIONAL_DIB_ARGS="$OPTIONAL_DIB_ARGS -offline"
    fi

    if [ "$ENABLE_DEBUG_MODE" = "yes" ]; then
        OPTIONAL_DIB_ARGS="$OPTIONAL_DIB_ARGS -x"
        MANILA_USER_AUTHORIZED_KEYS=${MANILA_USER_AUTHORIZED_KEYS:-"$HOME/.ssh/id_rsa.pub"}
    fi

    if [ "$DISABLE_IMG_COMPRESSION" = "yes" ]; then
        OPTIONAL_DIB_ARGS="$OPTIONAL_DIB_ARGS -u"
    fi
}

# Verify dependencies
# -------------------

is_installed() {
    if [ "$platform" = 'ubuntu' ]; then
        dpkg -s "$1" &> /dev/null
    else
        # centos, fedora, opensuse, or rhel
        if ! rpm -q "$1" &> /dev/null; then
            rpm -q "$(rpm -q --whatprovides "$1")"
        fi
    fi
}

need_required_packages() {
    case "$platform" in
        "ubuntu")
            package_list="qemu kpartx debootstrap"
            ;;
        "fedora")
            package_list="qemu-img kpartx debootstrap"
            ;;
        "opensuse")
            package_list="qemu kpartx debootstrap"
            ;;
        "rhel" | "centos")
            package_list="qemu-kvm qemu-img kpartx debootstrap"
            ;;
        *)
            err "Unknown platform '$platform' for the package list.\nAborting"
            exit 2
            ;;
    esac

    for p in `echo $package_list`; do
        if ! is_installed $p; then
            return 0
        fi
    done
    return 1
}

verify_dependencies() {
    if [ -e /etc/os-release ]; then
        platform=$(cat /etc/os-release | awk -F= '/^ID=/ {print tolower($2);}')
        # remove eventual quotes around ID=...
        platform=$(echo $platform | sed -e 's,^",,;s,"$,,')
    elif [ -e /etc/system-release ]; then
        case "$(head -1 /etc/system-release)" in
            "Red Hat Enterprise Linux Server"*)
                platform=rhel
                ;;
            "CentOS"*)
                platform=centos
                ;;
            *)
                err "Unknown value in /etc/system-release. Impossible to build images.\nAborting"
                exit 2
                ;;
        esac
    else
        err "Unknown host OS. Impossible to build images.\nAborting"
        exit 2
    fi

    if need_required_packages; then
        # install required packages if requested
        if [ -n "$DIB_UPDATE_REQUESTED" ]; then
            case "$platform" in
                "ubuntu")
                    sudo apt-get update
                    sudo apt-get install $package_list -y
                    ;;
                "opensuse")
                    sudo zypper --non-interactive --gpg-auto-import-keys in $package_list
                    ;;
                "fedora" | "rhel" | "centos")
                    if [ ${platform} = "fedora" ]; then
                        sudo dnf install $package_list -y
                    else
                        sudo yum install $package_list -y
                    fi
                    ;;
                *)
                    err "Unknown platform '$platform' for installing packages.\nAborting"
                    exit 2
                    ;;
            esac
        else
            err "Missing one of the following packages: $package_list"
            err "Please install manually or rerun with the update option (-u)."
            exit 1
        fi
    fi
}

# Build image
# -----------
build_image() {
    disk-image-create \
        -t $IMAGE_FORMAT \
        -a $MANILA_IMG_ARCH \
        $OPTIONAL_DIB_ARGS \
        -o $MANILA_IMG_NAME \
        $OPTIONAL_ELEMENTS $REQUIRED_ELEMENTS
}

main() {
    parse_arguments "$@"
    configure
    verify_dependencies
    build_image
    exit 0
}

main "$@"