/*
 * Copyright (c) 2020 Nordic Semiconductor ASA
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#include <zephyr/bluetooth/mesh.h>
#include <zephyr/bluetooth/bluetooth.h>

#include "mesh.h"
#include "net.h"
#include "rpl.h"
#include "beacon.h"
#include "settings.h"
#include "heartbeat.h"
#include "friend.h"
#include "cfg.h"
#include "od_priv_proxy.h"
#include "priv_beacon.h"

#define LOG_LEVEL CONFIG_BT_MESH_CFG_LOG_LEVEL
#include <zephyr/logging/log.h>
LOG_MODULE_REGISTER(bt_mesh_cfg);

/* Miscellaneous configuration server model states */
struct cfg_val {
	uint8_t net_transmit;
	uint8_t relay;
	uint8_t relay_retransmit;
	uint8_t beacon;
	uint8_t gatt_proxy;
	uint8_t frnd;
	uint8_t default_ttl;
};

void bt_mesh_beacon_set(bool beacon)
{
	if (atomic_test_bit(bt_mesh.flags, BT_MESH_BEACON) == beacon) {
		return;
	}

	atomic_set_bit_to(bt_mesh.flags, BT_MESH_BEACON, beacon);

	if (beacon) {
		bt_mesh_beacon_enable();
	} else {
		/* Beacon timer will stop automatically when all beacons are disabled. */
	}

	if (IS_ENABLED(CONFIG_BT_SETTINGS) &&
	    atomic_test_bit(bt_mesh.flags, BT_MESH_VALID)) {
		bt_mesh_settings_store_schedule(BT_MESH_SETTINGS_CFG_PENDING);
	}
}

bool bt_mesh_beacon_enabled(void)
{
	return atomic_test_bit(bt_mesh.flags, BT_MESH_BEACON);
}

static int feature_set(int feature_flag, enum bt_mesh_feat_state state)
{
	if (state != BT_MESH_FEATURE_DISABLED &&
	    state != BT_MESH_FEATURE_ENABLED) {
		return -EINVAL;
	}

	if (atomic_test_bit(bt_mesh.flags, feature_flag) ==
	    (state == BT_MESH_FEATURE_ENABLED)) {
		return -EALREADY;
	}

	atomic_set_bit_to(bt_mesh.flags, feature_flag,
			  (state == BT_MESH_FEATURE_ENABLED));

	return 0;
}

static enum bt_mesh_feat_state feature_get(int feature_flag)
{
	return atomic_test_bit(bt_mesh.flags, feature_flag) ?
		       BT_MESH_FEATURE_ENABLED :
		       BT_MESH_FEATURE_DISABLED;
}

int bt_mesh_priv_beacon_set(enum bt_mesh_feat_state priv_beacon)
{
	int err;

	if (!IS_ENABLED(CONFIG_BT_MESH_PRIV_BEACONS)) {
		return -ENOTSUP;
	}

	err = feature_set(BT_MESH_PRIV_BEACON, priv_beacon);
	if (err) {
		return err;
	}

	if (priv_beacon == BT_MESH_FEATURE_ENABLED) {
		bt_mesh_beacon_enable();
	} else {
		/* Beacon timer will stop automatically when all beacons are disabled. */
	}

	if (IS_ENABLED(CONFIG_BT_SETTINGS) && IS_ENABLED(CONFIG_BT_MESH_PRIV_BEACON_SRV) &&
	    atomic_test_bit(bt_mesh.flags, BT_MESH_VALID)) {
		bt_mesh_priv_beacon_srv_store_schedule();
	}

	return 0;
}

enum bt_mesh_feat_state bt_mesh_priv_beacon_get(void)
{
	if (!IS_ENABLED(CONFIG_BT_MESH_PRIV_BEACONS)) {
		return BT_MESH_FEATURE_NOT_SUPPORTED;
	}

	return feature_get(BT_MESH_PRIV_BEACON);
}

void bt_mesh_priv_beacon_update_interval_set(uint8_t interval)
{
#if defined(CONFIG_BT_MESH_PRIV_BEACONS)
	bt_mesh.priv_beacon_int = interval;
#endif
}

uint8_t bt_mesh_priv_beacon_update_interval_get(void)
{
#if defined(CONFIG_BT_MESH_PRIV_BEACONS)
	return bt_mesh.priv_beacon_int;
#else
	return 0;
#endif
}

int bt_mesh_od_priv_proxy_get(void)
{
#if IS_ENABLED(CONFIG_BT_MESH_OD_PRIV_PROXY_SRV)
	return bt_mesh.on_demand_state;
#else
	return -ENOTSUP;
#endif
}

int bt_mesh_od_priv_proxy_set(uint8_t on_demand_proxy)
{
#if !IS_ENABLED(CONFIG_BT_MESH_OD_PRIV_PROXY_SRV)
	return -ENOTSUP;
#else

	if (bt_mesh_priv_gatt_proxy_get() != BT_MESH_FEATURE_NOT_SUPPORTED) {
		bt_mesh.on_demand_state = on_demand_proxy;
	}

	if (IS_ENABLED(CONFIG_BT_SETTINGS) && IS_ENABLED(CONFIG_BT_MESH_OD_PRIV_PROXY_SRV) &&
	    atomic_test_bit(bt_mesh.flags, BT_MESH_VALID)) {
		bt_mesh_od_priv_proxy_srv_store_schedule();
	}
	return 0;
#endif
}

static bool node_id_is_running(struct bt_mesh_subnet *sub, void *cb_data)
{
	return sub->node_id == BT_MESH_NODE_IDENTITY_RUNNING;
}

int bt_mesh_gatt_proxy_set(enum bt_mesh_feat_state gatt_proxy)
{
	int err;

	if (!IS_ENABLED(CONFIG_BT_MESH_GATT_PROXY)) {
		return -ENOTSUP;
	}

	err = feature_set(BT_MESH_GATT_PROXY, gatt_proxy);
	if (err) {
		return err;
	}

	/* The binding from section 4.2.45.1 disables Private GATT Proxy state when non-private
	 * state is enabled.
	 */
	if (gatt_proxy == BT_MESH_FEATURE_ENABLED) {
		feature_set(BT_MESH_PRIV_GATT_PROXY, BT_MESH_FEATURE_DISABLED);
	}

	if ((gatt_proxy == BT_MESH_FEATURE_ENABLED) ||
	    (gatt_proxy == BT_MESH_FEATURE_DISABLED &&
	     !bt_mesh_subnet_find(node_id_is_running, NULL))) {
		bt_mesh_adv_gatt_update();
	}

	bt_mesh_hb_feature_changed(BT_MESH_FEAT_PROXY);

	if (IS_ENABLED(CONFIG_BT_SETTINGS) &&
	    atomic_test_bit(bt_mesh.flags, BT_MESH_VALID)) {
		bt_mesh_settings_store_schedule(BT_MESH_SETTINGS_CFG_PENDING);
	}

	return 0;
}

enum bt_mesh_feat_state bt_mesh_gatt_proxy_get(void)
{
	if (!IS_ENABLED(CONFIG_BT_MESH_GATT_PROXY)) {
		return BT_MESH_FEATURE_NOT_SUPPORTED;
	}

	return feature_get(BT_MESH_GATT_PROXY);
}

int bt_mesh_priv_gatt_proxy_set(enum bt_mesh_feat_state priv_gatt_proxy)
{
	int err;

	if (!IS_ENABLED(CONFIG_BT_MESH_GATT_PROXY) || !IS_ENABLED(CONFIG_BT_MESH_PRIV_BEACONS)) {
		return BT_MESH_FEATURE_NOT_SUPPORTED;
	}

	/* Reverse binding from section 4.2.45.1 doesn't allow to enable private state if
	 * non-private state is enabled.
	 */
	if (bt_mesh_gatt_proxy_get() == BT_MESH_FEATURE_ENABLED) {
		return BT_MESH_FEATURE_DISABLED;
	}

	err = feature_set(BT_MESH_PRIV_GATT_PROXY, priv_gatt_proxy);
	if (err) {
		return err;
	}

	if (priv_gatt_proxy == BT_MESH_FEATURE_ENABLED) {
		/* Re-generate proxy beacon */
		bt_mesh_adv_gatt_update();
	}

	if (IS_ENABLED(CONFIG_BT_SETTINGS) && IS_ENABLED(CONFIG_BT_MESH_PRIV_BEACON_SRV) &&
	    atomic_test_bit(bt_mesh.flags, BT_MESH_VALID)) {
		bt_mesh_priv_beacon_srv_store_schedule();
	}

	return 0;
}

enum bt_mesh_feat_state bt_mesh_priv_gatt_proxy_get(void)
{
	if (!IS_ENABLED(CONFIG_BT_MESH_GATT_PROXY) || !IS_ENABLED(CONFIG_BT_MESH_PRIV_BEACONS)) {
		return BT_MESH_FEATURE_NOT_SUPPORTED;
	}

	return feature_get(BT_MESH_PRIV_GATT_PROXY);
}

int bt_mesh_default_ttl_set(uint8_t default_ttl)
{
	if (default_ttl == 1 || default_ttl > BT_MESH_TTL_MAX) {
		return -EINVAL;
	}

	if (default_ttl == bt_mesh.default_ttl) {
		return 0;
	}

	bt_mesh.default_ttl = default_ttl;

	if (IS_ENABLED(CONFIG_BT_SETTINGS) &&
	    atomic_test_bit(bt_mesh.flags, BT_MESH_VALID)) {
		bt_mesh_settings_store_schedule(BT_MESH_SETTINGS_CFG_PENDING);
	}

	return 0;
}

uint8_t bt_mesh_default_ttl_get(void)
{
	return bt_mesh.default_ttl;
}

int bt_mesh_friend_set(enum bt_mesh_feat_state friendship)
{
	int err;

	if (!IS_ENABLED(CONFIG_BT_MESH_FRIEND)) {
		return -ENOTSUP;
	}

	err = feature_set(BT_MESH_FRIEND, friendship);
	if (err) {
		return err;
	}

	bt_mesh_hb_feature_changed(BT_MESH_FEAT_FRIEND);

	if (IS_ENABLED(CONFIG_BT_SETTINGS) &&
	    atomic_test_bit(bt_mesh.flags, BT_MESH_VALID)) {
		bt_mesh_settings_store_schedule(BT_MESH_SETTINGS_CFG_PENDING);
	}

	if (friendship == BT_MESH_FEATURE_DISABLED) {
		bt_mesh_friends_clear();
	}

	return 0;
}

enum bt_mesh_feat_state bt_mesh_friend_get(void)
{
	if (!IS_ENABLED(CONFIG_BT_MESH_FRIEND)) {
		return BT_MESH_FEATURE_NOT_SUPPORTED;
	}

	return feature_get(BT_MESH_FRIEND);
}

void bt_mesh_net_transmit_set(uint8_t xmit)
{
	if (bt_mesh.net_xmit == xmit) {
		return;
	}

	bt_mesh.net_xmit = xmit;

	if (IS_ENABLED(CONFIG_BT_SETTINGS) &&
	    atomic_test_bit(bt_mesh.flags, BT_MESH_VALID)) {
		bt_mesh_settings_store_schedule(BT_MESH_SETTINGS_CFG_PENDING);
	}
}

uint8_t bt_mesh_net_transmit_get(void)
{
	return bt_mesh.net_xmit;
}

int bt_mesh_relay_set(enum bt_mesh_feat_state relay, uint8_t xmit)
{
	int err;

	if (!IS_ENABLED(CONFIG_BT_MESH_RELAY)) {
		return -ENOTSUP;
	}

	err = feature_set(BT_MESH_RELAY, relay);
	if (err == -EINVAL) {
		return err;
	}

	if (err == -EALREADY && bt_mesh.relay_xmit == xmit) {
		return -EALREADY;
	}

	bt_mesh.relay_xmit = xmit;
	bt_mesh_hb_feature_changed(BT_MESH_FEAT_RELAY);

	if (IS_ENABLED(CONFIG_BT_SETTINGS) &&
	    atomic_test_bit(bt_mesh.flags, BT_MESH_VALID)) {
		bt_mesh_settings_store_schedule(BT_MESH_SETTINGS_CFG_PENDING);
	}

	return 0;
}

enum bt_mesh_feat_state bt_mesh_relay_get(void)
{
	return feature_get(BT_MESH_RELAY);
}

uint8_t bt_mesh_relay_retransmit_get(void)
{
	if (!IS_ENABLED(CONFIG_BT_MESH_RELAY)) {
		return 0;
	}

	return bt_mesh.relay_xmit;
}

bool bt_mesh_fixed_group_match(uint16_t addr)
{
	/* Check for fixed group addresses */
	switch (addr) {
	case BT_MESH_ADDR_ALL_NODES:
		return true;
	case BT_MESH_ADDR_PROXIES:
		return (bt_mesh_gatt_proxy_get() == BT_MESH_FEATURE_ENABLED);
	case BT_MESH_ADDR_FRIENDS:
		return (bt_mesh_friend_get() == BT_MESH_FEATURE_ENABLED);
	case BT_MESH_ADDR_RELAYS:
		return (bt_mesh_relay_get() == BT_MESH_FEATURE_ENABLED);
	default:
		return false;
	}
}

void bt_mesh_cfg_default_set(void)
{
	bt_mesh.default_ttl = CONFIG_BT_MESH_DEFAULT_TTL;
	bt_mesh.net_xmit =
		BT_MESH_TRANSMIT(CONFIG_BT_MESH_NETWORK_TRANSMIT_COUNT,
				 CONFIG_BT_MESH_NETWORK_TRANSMIT_INTERVAL);

#if defined(CONFIG_BT_MESH_RELAY)
	bt_mesh.relay_xmit =
		BT_MESH_TRANSMIT(CONFIG_BT_MESH_RELAY_RETRANSMIT_COUNT,
				 CONFIG_BT_MESH_RELAY_RETRANSMIT_INTERVAL);
#endif

	if (IS_ENABLED(CONFIG_BT_MESH_RELAY_ENABLED)) {
		atomic_set_bit(bt_mesh.flags, BT_MESH_RELAY);
	}

	if (IS_ENABLED(CONFIG_BT_MESH_BEACON_ENABLED)) {
		atomic_set_bit(bt_mesh.flags, BT_MESH_BEACON);
	}

	if (IS_ENABLED(CONFIG_BT_MESH_GATT_PROXY_ENABLED)) {
		atomic_set_bit(bt_mesh.flags, BT_MESH_GATT_PROXY);
	}

	if (IS_ENABLED(CONFIG_BT_MESH_FRIEND_ENABLED)) {
		atomic_set_bit(bt_mesh.flags, BT_MESH_FRIEND);
	}
}

static int cfg_set(const char *name, size_t len_rd,
		   settings_read_cb read_cb, void *cb_arg)
{
	struct cfg_val cfg;
	int err;

	if (len_rd == 0) {
		LOG_DBG("Cleared configuration state");
		return 0;
	}

	err = bt_mesh_settings_set(read_cb, cb_arg, &cfg, sizeof(cfg));
	if (err) {
		LOG_ERR("Failed to set \'cfg\'");
		return err;
	}

	bt_mesh_net_transmit_set(cfg.net_transmit);
	bt_mesh_relay_set(cfg.relay, cfg.relay_retransmit);
	bt_mesh_beacon_set(cfg.beacon);
	bt_mesh_gatt_proxy_set(cfg.gatt_proxy);
	bt_mesh_friend_set(cfg.frnd);
	bt_mesh_default_ttl_set(cfg.default_ttl);

	LOG_DBG("Restored configuration state");

	return 0;
}

BT_MESH_SETTINGS_DEFINE(cfg, "Cfg", cfg_set);

static void clear_cfg(void)
{
	int err;

	err = settings_delete("bt/mesh/Cfg");
	if (err) {
		LOG_ERR("Failed to clear configuration (err: %d)", err);
	} else {
		LOG_DBG("Cleared configuration");
	}
}

static void store_pending_cfg(void)
{
	struct cfg_val val;
	int err;

	val.net_transmit = bt_mesh_net_transmit_get();
	val.relay = bt_mesh_relay_get();
	val.relay_retransmit = bt_mesh_relay_retransmit_get();
	val.beacon = bt_mesh_beacon_enabled();
	val.gatt_proxy = bt_mesh_gatt_proxy_get();
	val.frnd = bt_mesh_friend_get();
	val.default_ttl = bt_mesh_default_ttl_get();

	err = settings_save_one("bt/mesh/Cfg", &val, sizeof(val));
	if (err) {
		LOG_ERR("Failed to store configuration value");
	} else {
		LOG_DBG("Stored configuration value");
		LOG_HEXDUMP_DBG(&val, sizeof(val), "raw value");
	}
}

void bt_mesh_cfg_pending_store(void)
{
	if (atomic_test_bit(bt_mesh.flags, BT_MESH_VALID)) {
		store_pending_cfg();
	} else {
		clear_cfg();
	}
}