#!/bin/sh

# Copyright (C) 2015  Codethink Limited
#
# This program is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; version 2 of the License.
#
# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License along
# with this program.  If not, see <http://www.gnu.org/licenses/>.

set -e

ROOT="$1"

enable(){
    ln -sf "/usr/lib/systemd/system/$1.service" \
            "$ROOT/etc/systemd/system/multi-user.target.wants/$1.service"
}

unnaceptable(){
    eval echo Unexpected value \$$1 for $1 >&2
    exit 1
}

check_bool(){
    case "$(eval echo \"\$$1\")" in
    True)
        eval "$1=true"
        ;;
    False|'')
        eval "$1=false"
        ;;
    *)
        unnaceptable "$1"
        ;;
    esac
}

check_weston_config(){
    weston_ini_folder="$ROOT/usr/share/doc/weston"
    case "$GENIVI_WESTON_CONFIG" in
    'baseline'|'')
        weston_ini_file=ivi-shell-weston.ini
        ;;
    'gdp')
        weston_ini_file=gdp-weston.ini
        ;;
    *)
        unnaceptable "GENIVI_WESTON_CONFIG"
        ;;
    esac
    weston_ini_file="$weston_ini_folder/$weston_ini_file"
    if [ ! -f "$weston_ini_file" ]; then
        echo ERROR: Failed to locate weston config file: $weston_ini_file
        exit 1
    fi
}

check_weston_backend (){
    # If nothing defined, use drm-backend.so
    if [ "x$GENIVI_WESTON_BACKEND" == "x" ]; then
        echo GENIVI_WESTON_BACLEND not set, defaulting to drm-backend.so
        GENIVI_WESTON_BACKEND=drm-backend.so
    fi

    backends_folder="$ROOT/usr/lib/weston"
    backend_file="$backends_folder/$GENIVI_WESTON_BACKEND"
    # Check that the backend exists
    echo Checking for "$backend_file" ...
    if [ ! -f "$backend_file" ]; then
        echo "File $backend_file doesn't exist"
        GENIVI_WESTON_BACKEND="$GENIVI_WESTON_BACKEND-backend.so"
        backend_file="$backends_folder/$GENIVI_WESTON_BACKEND"
        echo Checking for "$backend_file" ...
        if [ ! -f "$backend_file" ]; then
            echo "File $backend_file doesn't exist"
            echo ERROR: Failed to find Weston backend in the system
            exit 1
        fi
    fi
    echo Backend $backend_file found
}

##########################################################################
# Check variables
##########################################################################

check_bool GENIVI_WESTON_AUTOSTART
check_weston_config
check_weston_backend

######################################
# Create and enable weston.service   #
######################################

cat > "$ROOT/usr/lib/systemd/system/weston.service" <<EOF
[Unit]
Description=Weston reference Wayland compositor
After=dbus.service

[Service]
ExecStart=/usr/bin/weston-launch -u root -- --log=/tmp/weston.log --backend="$GENIVI_WESTON_BACKEND"
ExecStop=/usr/bin/killall -s KILL weston

[Install]
WantedBy=multi-user.target
EOF

if "$GENIVI_WESTON_AUTOSTART"; then
    enable weston
fi

######################################
# Set weston.ini file                #
######################################

install -d "$ROOT/etc/xdg/weston"
install -m 0644 $weston_ini_file "$ROOT/etc/xdg/weston/weston.ini"