#!/bin/sh

set -e
set -u

. gettext.sh
TEXTDOMAIN="tails"
export TEXTDOMAIN

# Import the TBB_EXT variable, and guess_best_tor_browser_locale().
. /usr/local/lib/tails-shell-library/tor-browser.sh

# Import try_cleanup_browser_chroot(), setup_browser_chroot(),
# configure_chroot_dns_servers(), configure_chroot_browser(),
# configure_chroot_browser(), set_chroot_browser_locale()
# set_chroot_torbutton_browser_name(), set_chroot_browser_permissions()
# and run_browser_in_chroot().
. /usr/local/lib/tails-shell-library/chroot-browser.sh

# Import i2p_router_console_is_ready() and i2p_is_enabled().
. /usr/local/lib/tails-shell-library/i2p.sh

error () {
    local cli_text="${CMD}: `gettext \"error:\"` ${@}"
    local dialog_text="<b><big>`gettext \"Error\"`</big></b>

${@}"
    echo "${cli_text}" >&2
    sudo -u "${SUDO_USER}" zenity --error --title "" --text "${dialog_text}"
    exit 1
}

verify_start () {
    # Make sure the user really wants to start the browser in case the router console isn't available
    local dialog_msg="<b><big>`gettext \"Do you still want to launch I2P Browser?\"`</big></b>

`gettext \"The I2P router console is not ready.\"`"
    local launch="`gettext \"_Launch\"`"
    local exit="`gettext \"_Exit\"`"
    # Since zenity can't set the default button to cancel, we switch the
    # labels and interpret the return value as its negation.
    if sudo -u "${SUDO_USER}" zenity --question --title "" --ok-label "${exit}" \
       --cancel-label "${launch}" --text "${dialog_msg}"; then
        exit 0
    fi
}

show_start_notification () {
    local title="`gettext \"Starting the I2P Browser...\"`"
    local body="`gettext \"This may take a while, so please be patient.\"`"
    tails-notify-user "${title}" "${body}" 10000
}

copy_extra_tbb_prefs () {
    local chroot="${1}"
    local browser_name="${2}"
    local browser_user="${3}"

    local tbb_prefs="/etc/tor-browser/profile/preferences"
    local browser_prefs_dir="${chroot}/home/${browser_user}/.${browser_name}/profile.default/preferences"
    mkdir -p "${browser_prefs_dir}"
    # Selectively copy the TBB prefs we want
    sed '/\(security\|update\|download\|spell\|noscript\|torbrowser\)/!d' "${tbb_prefs}/0000tails.js" > \
                    "${browser_prefs_dir}/0000tails.js"
    sed '/\(capability\|noscript\)/!d' "${tbb_prefs}/extension-overrides.js" > \
                    "${browser_prefs_dir}/extension-overrides.js"
    chown -R "${browser_user}:${browser_user}" "${browser_prefs_dir}"
}

show_shutdown_notification () {
    local title="`gettext \"Shutting down the I2P Browser...\"`"
    local body="`gettext \"This may take a while, and you may not restart the I2P Browser until it is properly shut down.\"`"
    tails-notify-user "${title}" "${body}" 10000
}

# Main script:

# This isn't very useful without I2P...
i2p_is_enabled || exit 0

CMD="$(basename "${0}")"
LOCK="/var/lock/${CMD}"
CONF_DIR="/var/lib/i2p-browser"
COW="${CONF_DIR}/cow"
CHROOT="${CONF_DIR}/chroot"
BROWSER_NAME="i2p-browser"
BROWSER_USER="i2pbrowser"
HOME_PAGE="http://127.0.0.1:7657"
NOSCRIPT_EXT_XPI="${TBB_EXT}/{73a6fe31-595d-460b-a920-fcc0f8843232}.xpi"
TORBUTTON_EXT_DIR="${TBB_EXT}/torbutton@torproject.org"
HUMAN_READABLE_NAME="`gettext \"I2P Browser\"`"
IP4_NAMESERVERS="0.0.0.0"

# Prevent multiple instances of the script.
exec 9>"${LOCK}"
if ! flock -x -n 9; then
    error "`gettext \"Another I2P Browser is currently running, or being cleaned up. Please retry in a while.\"`"
fi

if ! i2p_router_console_is_ready; then
    verify_start
fi
show_start_notification

echo "* Setting up chroot"
setup_chroot_for_browser "${CHROOT}" "${COW}" "${BROWSER_USER}" || \
    error "`gettext \"Failed to setup chroot.\"`"

echo "* Configuring chroot"
configure_chroot_browser "${CHROOT}" "${BROWSER_USER}" "${BROWSER_NAME}" \
    "${HUMAN_READABLE_NAME}" "${HOME_PAGE}" "${IP4_NAMESERVERS}" \
    "${TBB_EXT}"/langpack-*.xpi "${NOSCRIPT_EXT_XPI}" "${TORBUTTON_EXT_DIR}" && \
    copy_extra_tbb_prefs "${CHROOT}" "${BROWSER_NAME}" "${BROWSER_USER}" || \
        error "`gettext \"Failed to configure browser.\"`"

echo "* Starting I2P Browser"
run_browser_in_chroot "${CHROOT}" "${BROWSER_NAME}" "${BROWSER_USER}" \
    "${SUDO_USER}" || \
    error "`gettext \"Failed to run browser.\"`"

echo "* Exiting the I2P Browser"
show_shutdown_notification

exit 0