#!/usr/bin/env bash
# -*- coding: utf-8; mode: sh indent-tabs-mode: nil -*-
# SPDX-License-Identifier: AGPL-3.0-or-later
# shellcheck disable=SC2001

# shellcheck source=utils/lib.sh
source "$(dirname "${BASH_SOURCE[0]}")/lib.sh"
source_dot_config

# ----------------------------------------------------------------------------
# config
# ----------------------------------------------------------------------------

SEARX_INTERNAL_URL="${SEARX_INTERNAL_URL:-127.0.0.1:8888}"

SEARX_URL_PATH="${SEARX_URL_PATH:-$(echo "${PUBLIC_URL}" \
| sed -e 's,^.*://[^/]*\(/.*\),\1,g')}"
[[ "${SEARX_URL_PATH}" == "${PUBLIC_URL}" ]] && SEARX_URL_PATH=/
SEARX_INSTANCE_NAME="${SEARX_INSTANCE_NAME:-searx@$(echo "$PUBLIC_URL" \
| sed -e 's,^.*://\([^\:/]*\).*,\1,g') }"

SERVICE_NAME="searx"
SERVICE_USER="${SERVICE_USER:-${SERVICE_NAME}}"
SERVICE_HOME_BASE="${SERVICE_HOME_BASE:-/usr/local}"
SERVICE_HOME="${SERVICE_HOME_BASE}/${SERVICE_USER}"
# shellcheck disable=SC2034
SERVICE_GROUP="${SERVICE_USER}"

SEARX_GIT_URL="${SEARX_GIT_URL:-https://github.com/asciimoo/searx.git}"
SEARX_GIT_BRANCH="${SEARX_GIT_BRANCH:-master}"
SEARX_PYENV="${SERVICE_HOME}/searx-pyenv"
SEARX_SRC="${SERVICE_HOME}/searx-src"
SEARX_SETTINGS_PATH="/etc/searx/settings.yml"
SEARX_UWSGI_APP="searx.ini"
# shellcheck disable=SC2034
SEARX_UWSGI_SOCKET="/run/uwsgi/app/searx/socket"

case $DIST_ID in
    ubuntu|debian)  # apt packages
        SEARX_PACKAGES="\
 python3-dev python3-babel python3-venv \
 uwsgi uwsgi-plugin-python3 \
 git build-essential libxslt-dev zlib1g-dev libffi-dev libssl-dev "
        ;;
    arch)           # pacman packages
        # FIXME:
        # - /usr/lib/uwsgi/http_plugin.so: cannot open shared object file: No such file or directory !!!
        # - /usr/lib/uwsgi/systemd_logger_plugin.so: cannot open shared object file: No such file or directory !!!
        SEARX_PACKAGES="\
 python python-pip python-lxml python-babel \
 uwsgi uwsgi-plugin-python \
 git base-devel libxml2 "
        ;;
    fedora)          # dnf packages
        SEARX_PACKAGES="\
 python python-pip python-lxml python-babel \
 uwsgi uwsgi-plugin-python3 \
 git @development-tools libxml2 "
        ;;
esac

# Apache Settings

APACHE_APT_PACKAGES="\
  libapache2-mod-uwsgi \
"

APACHE_SEARX_SITE="searx.conf"

# shellcheck disable=SC2034
CONFIG_FILES=(
    "${uWSGI_APPS_AVAILABLE}/${SEARX_UWSGI_APP}"
)

# shellcheck disable=SC2034
CONFIG_BACKUP_ENCRYPTED=(
    "${SEARX_SETTINGS_PATH}"
)

# ----------------------------------------------------------------------------
usage() {
# ----------------------------------------------------------------------------

    # shellcheck disable=SC1117
    cat <<EOF

usage::

  $(basename "$0") shell
  $(basename "$0") install    [all|user|searx-src|pyenv|apache]
  $(basename "$0") update     [searx]
  $(basename "$0") remove     [all|user|pyenv|searx-src]
  $(basename "$0") activate   [service]
  $(basename "$0") deactivate [service]
  $(basename "$0") inspect    [service]
  $(basename "$0") option     [debug-on|debug-off]
  $(basename "$0") apache     [install|remove]

shell
  start interactive shell from user ${SERVICE_USER}
install / remove
  :all:        complete (de-) installation of searx service
  :user:       add/remove service user '$SERVICE_USER' ($SERVICE_HOME)
  :searx-src:  clone $SEARX_GIT_URL
  :pyenv:      create/remove virtualenv (python) in $SEARX_PYENV
  :settings:   reinstall settings from ${REPO_ROOT}/searx/settings.yml
update searx
  Update searx installation ($SERVICE_HOME)
activate service
  activate and start service daemon (systemd unit)
deactivate service
  stop and deactivate service daemon (systemd unit)
inspect service
  run some small tests and inspect service's status and log
option
  set one of the available options
apache
  :install: apache site with the searx uwsgi app
  :remove:  apache site ${APACHE_FILTRON_SITE}

searx settings: ${SEARX_SETTINGS_PATH}

If needed, set PUBLIC_URL of your WEB service in the '${DOT_CONFIG#"$REPO_ROOT/"}' file::

  PUBLIC_URL          : ${PUBLIC_URL}
  PUBLIC_HOST         : ${PUBLIC_HOST}
  SEARX_INSTANCE_NAME : ${SEARX_INSTANCE_NAME}
  SERVICE_USER        : ${SERVICE_USER}

EOF
    [[ -n ${1} ]] &&  err_msg "$1"
}

main() {
    rst_title "$SEARX_INSTANCE_NAME" part

    required_commands \
        sudo systemctl install git wget curl \
        || exit

    local _usage="unknown or missing $1 command $2"

    case $1 in
        --source-only)  ;;
        -h|--help) usage; exit 0;;

        shell)
            sudo_or_exit
            interactive_shell "${SERVICE_USER}"
            ;;
        inspect)
            case $2 in
                service)
                    sudo_or_exit
                    inspect_service
                    ;;
                *) usage "$_usage"; exit 42;;
            esac ;;
        install)
            sudo_or_exit
            case $2 in
                all) install_all ;;
                user) assert_user ;;
                pyenv) create_pyenv ;;
                searx-src) clone_searx ;;
                settings) install_settings ;;
                *) usage "$_usage"; exit 42;;
            esac ;;
        update)
            sudo_or_exit
            case $2 in
                searx) update_searx;;
                *) usage "$_usage"; exit 42;;
            esac ;;
        remove)
            sudo_or_exit
            case $2 in
                all) remove_all;;
                user) drop_service_account "${SERVICE_USER}";;
                pyenv) remove_pyenv ;;
                searx-src) remove_searx ;;
                *) usage "$_usage"; exit 42;;
            esac ;;
        activate)
            sudo_or_exit
            case $2 in
                service)
                    activate_service ;;
                *) usage "$_usage"; exit 42;;
            esac ;;
        deactivate)
            sudo_or_exit
            case $2 in
                service)  deactivate_service ;;
                *) usage "$_usage"; exit 42;;
            esac ;;
        option)
            sudo_or_exit
            case $2 in
                debug-on)  echo; enable_debug ;;
                debug-off)  echo; disable_debug ;;
                *) usage "$_usage"; exit 42;;
            esac ;;
        apache)
            sudo_or_exit
            case $2 in
                install) install_apache_site ;;
                remove) remove_apache_site ;;
                *) usage "$_usage"; exit 42;;
            esac ;;

        *) usage "unknown or missing command $1"; exit 42;;
    esac
}

_service_prefix="  |$SERVICE_USER| "

install_all() {
    rst_title "Install $SEARX_INSTANCE_NAME (service)"
    pkg_install "$SEARX_PACKAGES"
    wait_key
    assert_user
    wait_key
    clone_searx
    wait_key
    create_pyenv
    wait_key
    install_settings
    wait_key
    test_local_searx
    wait_key
    install_searx_uwsgi
    if ! service_is_available "http://$SEARX_INTERNAL_URL"; then
        err_msg "URL http://$SEARX_INTERNAL_URL not available, check searx & uwsgi setup!"
    fi
    if ask_yn "Do you want to inspect the installation?" Yn; then
        inspect_service
    fi
}

update_searx() {
    rst_title "Update searx instance"

    echo
    tee_stderr 0.3 <<EOF | sudo -H -u "${SERVICE_USER}" -i 2>&1 |  prefix_stdout "$_service_prefix"
cd ${SEARX_SRC}
git checkout -B "$SEARX_GIT_BRANCH"
git pull
${SEARX_SRC}/manage.sh update_packages
EOF
    install_settings
    uWSGI_restart "$SEARX_UWSGI_APP"
}

remove_all() {
    rst_title "De-Install $SEARX_INSTANCE_NAME (service)"

    rst_para "\
It goes without saying that this script can only be used to remove
installations that were installed with this script."

    if ! ask_yn "Do you really want to deinstall $SEARX_INSTANCE_NAME?"; then
        return
    fi
    remove_searx_uwsgi
    drop_service_account "${SERVICE_USER}"
    remove_settings
    wait_key
    if service_is_available "${PUBLIC_URL}"; then
        MSG="** Don't forgett to remove your public site! (${PUBLIC_URL}) **" wait_key 10
    fi
}

assert_user() {
    rst_title "user $SERVICE_USER" section
    echo
    tee_stderr 1 <<EOF | bash | prefix_stdout
useradd --shell /bin/bash --system \
 --home-dir "$SERVICE_HOME" \
 --comment 'Privacy-respecting metasearch engine' $SERVICE_USER
mkdir "$SERVICE_HOME"
chown -R "$SERVICE_GROUP:$SERVICE_GROUP" "$SERVICE_HOME"
groups $SERVICE_USER
EOF
    #SERVICE_HOME="$(sudo -i -u "$SERVICE_USER" echo \$HOME)"
    #export SERVICE_HOME
    #echo "export SERVICE_HOME=$SERVICE_HOME"
}

clone_is_available() {
    [[ -f "$SEARX_SRC/.git/config" ]]
}

# shellcheck disable=SC2164
clone_searx() {
    rst_title "Clone searx sources" section
    echo
    SERVICE_HOME="$(sudo -i -u "$SERVICE_USER" echo \$HOME 2>/dev/null)"
    if [[ ! "${SERVICE_HOME}" ]]; then
        err_msg "to clone searx sources, user $SERVICE_USER hast to be created first"
        return 42
    fi
    export SERVICE_HOME
    git_clone "$REPO_ROOT" "$SEARX_SRC" \
              "$SEARX_GIT_BRANCH" "$SERVICE_USER"

    pushd "${SEARX_SRC}" > /dev/null
    tee_stderr 0.1 <<EOF | sudo -H -u "${SERVICE_USER}" -i 2>&1 | prefix_stdout "$_service_prefix"
cd "${SEARX_SRC}"
git remote set-url origin ${SEARX_GIT_URL}
git config user.email "$ADMIN_EMAIL"
git config user.name "$ADMIN_NAME"
git config --list
EOF
    popd > /dev/null
}

install_settings() {
    rst_title "${SEARX_SETTINGS_PATH}" section
    if ! clone_is_available; then
        err_msg "you have to install searx first"
        exit 42
    fi
    mkdir -p "$(dirname ${SEARX_SETTINGS_PATH})"

    if [[ ! -f ${SEARX_SETTINGS_PATH} ]]; then
        info_msg "install settings ${REPO_ROOT}/searx/settings.yml"
        info_msg "  --> ${SEARX_SETTINGS_PATH}"
        cp "${REPO_ROOT}/searx/settings.yml" "${SEARX_SETTINGS_PATH}"
        configure_searx
        return
    fi

    rst_para "Diff between origin's setting file (-) and current (+):"
    echo
    $DIFF_CMD "${SEARX_SRC}/searx/settings.yml" "${SEARX_SETTINGS_PATH}"

    local action
    choose_one action "What should happen to the settings file? " \
           "keep new configuration" \
           "start interactiv shell"
    case $action in
        "keep new configuration")
            info_msg "continue using new settings file"
            ;;
        "start interactiv shell")
            echo -e "// exit with [${_BCyan}CTRL-D${_creset}]"
            sudo -H -i
            rst_para 'Diff between new setting file (-) and current (+):'
            echo
            $DIFF_CMD "${SEARX_SRC}/searx/settings.yml" "${SEARX_SETTINGS_PATH}" 
            wait_key
            ;;
    esac
}

remove_settings() {
    rst_title "remove searx settings" section
    echo
    info_msg "delete ${SEARX_SETTINGS_PATH}"
    rm -f "${SEARX_SETTINGS_PATH}"
}

remove_searx() {
    rst_title "Drop searx sources" section
    if ask_yn "Do you really want to drop searx sources ($SEARX_SRC)?"; then
        rm -rf "$SEARX_SRC"
    else
        rst_para "Leave searx sources unchanged."
    fi
}

pyenv_is_available() {
    [[ -f "${SEARX_PYENV}/bin/activate" ]]
}

create_pyenv() {
    rst_title "Create virtualenv (python)" section
    echo
    if [[ ! -f "${SEARX_SRC}/manage.sh" ]]; then
        err_msg "to create pyenv for searx, searx has to be cloned first"
        return 42
    fi
    info_msg "create pyenv in ${SEARX_PYENV}"
    tee_stderr 0.1 <<EOF | sudo -H -u "${SERVICE_USER}" -i 2>&1 |  prefix_stdout "$_service_prefix"
rm -rf "${SEARX_PYENV}"
python3 -m venv "${SEARX_PYENV}"
grep -qFs -- 'source ${SEARX_PYENV}/bin/activate' ~/.profile \
  || echo 'source ${SEARX_PYENV}/bin/activate' >> ~/.profile
EOF
    info_msg "inspect python's virtual environment"
    tee_stderr 0.1 <<EOF | sudo -H -u "${SERVICE_USER}" -i 2>&1 |  prefix_stdout "$_service_prefix"
command -v python && python --version
EOF
    wait_key
    info_msg "install needed python packages"
    tee_stderr 0.1 <<EOF | sudo -H -u "${SERVICE_USER}" -i 2>&1 |  prefix_stdout "$_service_prefix"
${SEARX_SRC}/manage.sh update_packages
EOF
}

remove_pyenv() {
    rst_title "Remove virtualenv (python)" section
    if ! ask_yn "Do you really want to drop ${SEARX_PYENV} ?"; then
        return
    fi
    info_msg "remove pyenv activation from ~/.profile"
    tee_stderr 0.1 <<EOF | sudo -H -u "${SERVICE_USER}" -i 2>&1 |  prefix_stdout "$_service_prefix"
grep -v 'source ${SEARX_PYENV}/bin/activate' ~/.profile > ~/.profile.##
mv ~/.profile.## ~/.profile
EOF
    rm -rf "${SEARX_PYENV}"
}

configure_searx() {
    rst_title "Configure searx" section
    rst_para "Setup searx config located at $SEARX_SETTINGS_PATH"
    echo
    tee_stderr 0.1 <<EOF | sudo -H -i 2>&1 |  prefix_stdout "$_service_prefix"
cd ${SEARX_SRC}
sed -i -e "s/ultrasecretkey/$(openssl rand -hex 16)/g" "$SEARX_SETTINGS_PATH"
sed -i -e "s/{instance_name}/${SEARX_INSTANCE_NAME}/g" "$SEARX_SETTINGS_PATH"
EOF
}

test_local_searx() {
    rst_title "Testing searx instance localy" section
    echo

    if service_is_available "http://$SEARX_INTERNAL_URL" &>/dev/null; then
        err_msg "URL/port http://$SEARX_INTERNAL_URL is already in use, you"
        err_msg "should stop that service before starting local tests!"
        if ! ask_yn "Continue with local tests?"; then
            return
        fi
    fi
    sed -i -e "s/debug : False/debug : True/g" "$SEARX_SETTINGS_PATH"
    tee_stderr 0.1 <<EOF | sudo -H -u "${SERVICE_USER}" -i 2>&1 |  prefix_stdout "$_service_prefix"
export SEARX_SETTINGS_PATH="${SEARX_SETTINGS_PATH}" 
cd ${SEARX_SRC}
timeout 10 python3 searx/webapp.py &
sleep 3
curl --location --verbose --head --insecure $SEARX_INTERNAL_URL
EOF
    sed -i -e "s/debug : True/debug : False/g" "$SEARX_SETTINGS_PATH"
}

install_searx_uwsgi() {
    rst_title "Install searx's uWSGI app (searx.ini)" section
    echo
    uWSGI_install_app "$SEARX_UWSGI_APP"
}

remove_searx_uwsgi() {
    rst_title "Remove searx's uWSGI app (searx.ini)" section
    echo
    uWSGI_remove_app "$SEARX_UWSGI_APP"
}

activate_service() {
    rst_title "Activate $SEARX_INSTANCE_NAME (service)" section
    echo
    uWSGI_enable_app "$SEARX_UWSGI_APP"
    uWSGI_restart "$SEARX_UWSGI_APP"
}

deactivate_service() {
    rst_title "De-Activate $SEARX_INSTANCE_NAME (service)" section
    echo
    uWSGI_disable_app "$SEARX_UWSGI_APP"
    uWSGI_restart "$SEARX_UWSGI_APP"
}

enable_debug() {
    warn_msg "Do not enable debug in production enviroments!!"
    info_msg "try to enable debug mode ..."
    tee_stderr 0.1 <<EOF | sudo -H -i 2>&1 |  prefix_stdout "$_service_prefix"
cd ${SEARX_SRC}
sed -i -e "s/debug : False/debug : True/g" "$SEARX_SETTINGS_PATH"
EOF
    uWSGI_restart "$SEARX_UWSGI_APP"
}

disable_debug() {
    info_msg "try to disable debug mode ..."
    tee_stderr 0.1 <<EOF | sudo -H -i 2>&1 |  prefix_stdout "$_service_prefix"
cd ${SEARX_SRC}
sed -i -e "s/debug : True/debug : False/g" "$SEARX_SETTINGS_PATH"
EOF
    uWSGI_restart "$SEARX_UWSGI_APP"
}

inspect_service() {
    rst_title "service status & log"
    cat <<EOF

sourced ${DOT_CONFIG#"$REPO_ROOT/"} :

  PUBLIC_URL          : ${PUBLIC_URL}
  PUBLIC_HOST         : ${PUBLIC_HOST}
  SEARX_URL_PATH      : ${SEARX_URL_PATH}
  SEARX_INSTANCE_NAME : ${SEARX_INSTANCE_NAME}
  SEARX_INTERNAL_URL  : ${SEARX_INTERNAL_URL}

EOF

    apache_is_installed && info_msg "Apache is installed."

    if service_account_is_available "$SERVICE_USER"; then
        info_msg "Service account $SERVICE_USER exists."
    else
        err_msg "Service account $SERVICE_USER does not exists!"
    fi

    if pyenv_is_available; then
        info_msg "~$SERVICE_USER: python environment is available."
    else
        err_msg "~$SERVICE_USER: python environment is not available!"
    fi

    if clone_is_available; then
        info_msg "~$SERVICE_USER: Searx software is installed."
    else
        err_msg "~$SERVICE_USER: Missing searx software!"
    fi

    if uWSGI_app_enabled "$SEARX_UWSGI_APP"; then
        info_msg "uWSGI app $SEARX_UWSGI_APP is enabled."
    else
        err_msg "uWSGI app $SEARX_UWSGI_APP not enabled!"
    fi

    uWSGI_app_available "$SEARX_UWSGI_APP" \
        || err_msg "uWSGI app $SEARX_UWSGI_APP not available!"

    if ! service_is_available "http://${SEARX_INTERNAL_URL}"; then
        err_msg "uWSGI app (service) at http://${SEARX_INTERNAL_URL} is not available!"
        echo -e "${_Green}stop with [${_BCyan}CTRL-C${_Green}] or .."
        wait_key
    fi

    if ! service_is_available "${PUBLIC_URL}"; then
        warn_msg "Public service at ${PUBLIC_URL} is not available!"
    fi

    local _debug_on
    if ask_yn "Enable searx debug mode?"; then
        enable_debug
        _debug_on=1
    fi
    echo
    systemctl --no-pager -l status "${SERVICE_NAME}"
    echo

    info_msg "public URL   --> ${PUBLIC_URL}"
    info_msg "internal URL --> http://${SEARX_INTERNAL_URL}"
    # shellcheck disable=SC2059
    printf "// use ${_BCyan}CTRL-C${_creset} to stop monitoring the log"
    read -r -s -n1 -t 2
    echo
    while true;  do
        trap break 2
        #journalctl -f -u "${SERVICE_NAME}"
        tail -f /var/log/uwsgi/app/searx.log
    done

    if [[ $_debug_on == 1 ]]; then
        disable_debug
    fi
    return 0
}

install_apache_site() {
    rst_title "Install Apache site $APACHE_SEARX_SITE"

    rst_para "\
This installs the searx uwsgi app as apache site.  If your server ist public to
the internet you should instead use a reverse proxy (filtron) to block
excessively bot queries."

    ! apache_is_installed && err_msg "Apache is not installed."

    if ! ask_yn "Do you really want to install apache site for searx-uwsgi?"; then
        return
    fi

    pkg_install "$APACHE_APT_PACKAGES"
    a2enmod uwsgi

    echo
    apache_install_site --variant=uwsgi "${APACHE_SEARX_SITE}"

    if ! service_is_available "${PUBLIC_URL}"; then
        err_msg "Public service at ${PUBLIC_URL} is not available!"
    fi
}

remove_apache_site() {

    rst_title "Remove Apache site ${APACHE_SEARX_SITE}"

    rst_para "\
This removes apache site ${APACHE_SEARX_SITE}."

    ! apache_is_installed && err_msg "Apache is not installed."

    if ! ask_yn "Do you really want to continue?"; then
        return
    fi

    apache_remove_site "${APACHE_SEARX_SITE}"
}

# ----------------------------------------------------------------------------
main "$@"
# ----------------------------------------------------------------------------