/*
 * Copyright (C) 2021 Twain Byrnes <binarynewts@google.com>
 * Copyright (C) 2021 George Popoola <gpopoola@google.com>
 *
 * SPDX-License-Identifier: LGPL-2.1+
 */

#include "config.h"

#include <fwupdplugin.h>

#define MINIMUM_BATTERY_PERCENTAGE_FALLBACK 10

struct FuPluginData {
	GDBusProxy *proxy; /* nullable */
};

void
fu_plugin_init (FuPlugin *plugin)
{
	fu_plugin_set_build_hash (plugin, FU_BUILD_HASH);
	fu_plugin_alloc_data (plugin, sizeof (FuPluginData));
}

void
fu_plugin_destroy (FuPlugin *plugin)
{
	FuPluginData *data = fu_plugin_get_data (plugin);
	if (data->proxy != NULL)
		g_object_unref (data->proxy);
}

gboolean
fu_plugin_startup (FuPlugin *plugin, GError **error)
{
	FuPluginData *data = fu_plugin_get_data (plugin);
	g_autoptr(GDBusConnection) connection = NULL;
	g_autofree gchar *name_owner = NULL;

	/* establishing DBus connection and proxy for method call to powerd */
	connection = g_bus_get_sync (G_BUS_TYPE_SYSTEM, NULL, error);

	if (connection == NULL) {
		g_prefix_error (error,
				"Connection with system was not established: ");
		return FALSE;
	}

	data->proxy = g_dbus_proxy_new_sync (connection,
					     G_DBUS_PROXY_FLAGS_NONE,
					     NULL,
					     "org.chromium.PowerManager",
					     "/org/chromium/PowerManager",
					     "org.chromium.PowerManager",
					     NULL,
					     error);

	if (data->proxy == NULL) {
		g_prefix_error (
		    error,
		    "Failed to establish proxy for power manager server: ");
		return FALSE;
	}

	name_owner = g_dbus_proxy_get_name_owner (data->proxy);
	if (name_owner == NULL) {
		g_set_error (error,
			     FWUPD_ERROR,
			     FWUPD_ERROR_NOT_SUPPORTED,
			     "No service that owns the name for %s",
			     g_dbus_proxy_get_name (data->proxy));
		return FALSE;
	}
	return TRUE;
}

gboolean
fu_plugin_update_prepare (FuPlugin *plugin,
			  FwupdInstallFlags flags,
			  FuDevice *device,
			  GError **error)
{
	FuPluginData *data = fu_plugin_get_data (plugin);
	guint32 power_type = 0;
	guint32 current_status = 0;
	gdouble current_percentage = 0;
	g_autoptr(GVariant) powerd_response = NULL;

	/* making method call to "GetBatteryState" through the proxy */
	powerd_response = g_dbus_proxy_call_sync (data->proxy,
						  "GetBatteryState",
						  NULL,
						  G_DBUS_CALL_FLAGS_NONE,
						  -1,
						  NULL,
						  error);

	if (powerd_response == NULL) {
		g_prefix_error (
		    error,
		    "Battery information from powerd was not loaded "
		    "successfully: ");
		return FALSE;
	}

	/* parsing data in powerd_response and inputting it into battery-check
	 * conditions */
	g_variant_get (powerd_response,
		       "(uud)",
		       &power_type,
		       &current_status,
		       &current_percentage);

	/* blocking updates if there is no AC power or if battery
	 * percentage is too low
	 */
	if (fu_device_has_flag (device, FWUPD_DEVICE_FLAG_REQUIRE_AC) &&
	    current_status == FU_BATTERY_STATE_DISCHARGING) {
		g_set_error (error,
			     FWUPD_ERROR,
			     FWUPD_ERROR_AC_POWER_REQUIRED,
			     "Cannot install update without external power "
			     "unless forced ");
		return FALSE;
	}

	if (current_percentage < MINIMUM_BATTERY_PERCENTAGE_FALLBACK) {
		g_set_error (error,
			     FWUPD_ERROR,
			     FWUPD_ERROR_BATTERY_LEVEL_TOO_LOW,
			     "Cannot install update when system battery "
			     "is not at least %i%% unless forced",
			     MINIMUM_BATTERY_PERCENTAGE_FALLBACK);
		return FALSE;
	}
	return TRUE;
}