#!/bin/sh
# Copyright (c) Advanced Micro Devices, Inc. All rights reserved.
#
# Permission is hereby granted, free of charge, to any person obtaining a copy
# of this software and associated documentation files (the "Software"), to deal
# in the Software without restriction, including without limitation the rights
# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
# copies of the Software, and to permit persons to whom the Software is
# furnished to do so, subject to the following conditions:
#
# The above copyright notice and this permission notice shall be included in
# all copies or substantial portions of the Software.
#
# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
# THE SOFTWARE.

# Post-installation script for amdcuid daemon.
# Template processed by CMake to generate the installed 'postinst' script.
# Do not edit the generated 'postinst' script directly; edit this 'postinst.in' template instead.
# This script reads the daemon config file to decide whether to install udev
# rules (daemonize=true) or a one-shot boot service (daemonize=false) for the daemon.

SCRIPT_DIR="$(dirname "$(readlink -f "$0")")"
CONFIG_DIR="@AMDCUID_SHARED_CONFIG_DIR@"
VERSIONED_CONFIG_FILE="$SCRIPT_DIR/config/amdcuid_daemon.conf"
CONFIG_FILE="$CONFIG_DIR/amdcuid_daemon.conf"
TOOL_BIN="$SCRIPT_DIR/../../bin/amdcuid_tool"
UDEV_RULES_FILE="/etc/udev/rules.d/90-amdcuid.rules"
SERVICE_NAME="amdcuid_daemon"

# Determine the correct systemd unit directory.
# DEB-based distros (Debian, Ubuntu) use /lib/systemd/system;
# RPM-based distros (RHEL, Fedora, SUSE) use /usr/lib/systemd/system.
if [ -f /etc/debian_version ]; then
    SYSTEMD_UNIT_DIR="/lib/systemd/system"
else
    SYSTEMD_UNIT_DIR="/usr/lib/systemd/system"
fi

if [ ! -f "$CONFIG_FILE" ]; then
    # First install: seed the shared config dir from the versioned defaults.
    mkdir -p "$CONFIG_DIR"
    chmod 755 "$CONFIG_DIR"
    if [ -f "$VERSIONED_CONFIG_FILE" ]; then
        cp "$VERSIONED_CONFIG_FILE" "$CONFIG_FILE"
    else
        echo "Warning: amdcuid config not found at $VERSIONED_CONFIG_FILE; skipping daemon setup."
        exit 0
    fi
fi

SETUP_HMAC="$SCRIPT_DIR/amdcuid_setup_hmac.sh"
if [ -x "$SETUP_HMAC" ]; then
    "$SETUP_HMAC"
else
    echo "POST-INSTALL ERROR: HMAC setup script not found at $SETUP_HMAC." >&2
    exit 1
fi

# Remove any existing service or udev rules in case we're upgrading from a
# previous install with different settings.
if systemctl is-active --quiet "$SERVICE_NAME" 2>/dev/null; then
    echo "Stopping $SERVICE_NAME..."
    systemctl stop "$SERVICE_NAME" || true
fi

if systemctl is-enabled --quiet "$SERVICE_NAME" 2>/dev/null; then
    echo "Disabling $SERVICE_NAME..."
    systemctl disable "$SERVICE_NAME" || true
fi

SERVICE_LINK="$SYSTEMD_UNIT_DIR/${SERVICE_NAME}.service"
if [ -L "$SERVICE_LINK" ] || [ -f "$SERVICE_LINK" ]; then
    echo "Removing systemd service file: $SERVICE_LINK"
    rm -f "$SERVICE_LINK"
fi

systemctl daemon-reload 2>/dev/null || true

if [ -f "$UDEV_RULES_FILE" ]; then
    echo "Removing udev rules: $UDEV_RULES_FILE"
    rm -f "$UDEV_RULES_FILE"
    udevadm control --reload-rules 2>/dev/null || true
    udevadm trigger 2>/dev/null || true
fi

DAEMONIZE=$(grep "^daemonize=" "$CONFIG_FILE" | cut -d'=' -f2 | tr -d '[:space:]')

if [ "$DAEMONIZE" = "true" ]; then
    # Persistent mode: install udev rules so the daemon is notified on device
    # changes, then enable and start the service.
    echo "Setting up udev rules for amdcuid daemon..."
    cat > "$UDEV_RULES_FILE" << EOF
# AMD CUID daemon udev rules
SUBSYSTEM=="drm", ACTION=="add|remove|change", RUN+="$TOOL_BIN --notify-daemon"
SUBSYSTEM=="net", ACTION=="add|remove|change", RUN+="$TOOL_BIN --notify-daemon"
EOF
    udevadm control --reload-rules
    udevadm trigger
fi

# Install, enable, and start the service regardless of mode.
# When daemonize=false the daemon runs once on start and exits with code 0;
# Restart=on-failure in the unit file will not trigger on a clean exit, so
# no additional unit type is required.
# To apply future config changes, edit the config file then run:
#   sudo systemctl restart amdcuid_daemon
if [ -d /run/systemd/system ]; then
    SERVICE_FILE="$SCRIPT_DIR/../../libexec/amdcuid/amdcuid_daemon.service"
    ACTUAL_DAEMON_BIN="$SCRIPT_DIR/../../bin/amdcuid_daemon"
    sed -i "s|^ExecStart=.*|ExecStart=${ACTUAL_DAEMON_BIN}|" "$SERVICE_FILE"
    ln -s -f -r "$SERVICE_FILE" "$SYSTEMD_UNIT_DIR/amdcuid_daemon.service"
fi
systemctl daemon-reload
systemctl enable "$SERVICE_NAME"
systemctl start "$SERVICE_NAME"