/*
 * Copyright (c) 2021 Nordic Semiconductor ASA
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#include <zephyr/device.h>
#include <zephyr/devicetree.h>
#include <zephyr/bluetooth/bluetooth.h>
#include <zephyr/bluetooth/conn.h>
#include <zephyr/bluetooth/hci.h>

static struct bt_conn *default_conn;

static K_SEM_DEFINE(sem_per_sync, 0, 1);
static K_SEM_DEFINE(sem_per_sync_lost, 0, 1);

static void sync_cb(struct bt_le_per_adv_sync *sync,
		    struct bt_le_per_adv_sync_synced_info *info)
{
	char le_addr[BT_ADDR_LE_STR_LEN];
	char past_peer_addr[BT_ADDR_LE_STR_LEN];

	if (!info->conn) {
		printk("Sync not from PAST\n");
		return;
	}

	bt_addr_le_to_str(info->addr, le_addr, sizeof(le_addr));

	bt_addr_le_to_str(bt_conn_get_dst(info->conn), past_peer_addr,
			  sizeof(past_peer_addr));

	printk("PER_ADV_SYNC[%u]: [DEVICE]: %s synced, Interval 0x%04x (%u ms). PAST peer %s\n",
	       bt_le_per_adv_sync_get_index(sync), le_addr, info->interval,
	       info->interval * 5 / 4, past_peer_addr);

	k_sem_give(&sem_per_sync);
}

static void term_cb(struct bt_le_per_adv_sync *sync,
		    const struct bt_le_per_adv_sync_term_info *info)
{
	char le_addr[BT_ADDR_LE_STR_LEN];

	bt_addr_le_to_str(info->addr, le_addr, sizeof(le_addr));

	printk("PER_ADV_SYNC[%u]: [DEVICE]: %s sync terminated\n",
	       bt_le_per_adv_sync_get_index(sync), le_addr);

	k_sem_give(&sem_per_sync_lost);
}

static void recv_cb(struct bt_le_per_adv_sync *sync,
		    const struct bt_le_per_adv_sync_recv_info *info,
		    struct net_buf_simple *buf)
{
	char le_addr[BT_ADDR_LE_STR_LEN];
	char data_str[129];

	bt_addr_le_to_str(info->addr, le_addr, sizeof(le_addr));
	bin2hex(buf->data, buf->len, data_str, sizeof(data_str));

	printk("PER_ADV_SYNC[%u]: [DEVICE]: %s, tx_power %i, RSSI %i, CTE %u, data length %u, "
	       "data: %s\n", bt_le_per_adv_sync_get_index(sync), le_addr,
	       info->tx_power, info->rssi, info->cte_type, buf->len, data_str);
}

static struct bt_le_per_adv_sync_cb sync_callbacks = {
	.synced = sync_cb,
	.term = term_cb,
	.recv = recv_cb
};

static void connected(struct bt_conn *conn, uint8_t err)
{
	char addr[BT_ADDR_LE_STR_LEN];

	bt_addr_le_to_str(bt_conn_get_dst(conn), addr, sizeof(addr));

	if (default_conn == NULL) {
		default_conn = bt_conn_ref(conn);
	}

	if (conn != default_conn) {
		return;
	}

	printk("Connected: %s\n", addr);
}

static void disconnected(struct bt_conn *conn, uint8_t reason)
{
	char addr[BT_ADDR_LE_STR_LEN];

	if (conn != default_conn) {
		return;
	}

	bt_addr_le_to_str(bt_conn_get_dst(conn), addr, sizeof(addr));

	printk("Disconnected: %s, reason 0x%02x %s\n", addr, reason, bt_hci_err_to_str(reason));

	bt_conn_unref(default_conn);
	default_conn = NULL;
}

static struct bt_conn_cb conn_callbacks = {
	.connected = connected,
	.disconnected = disconnected,
};

static const struct bt_data sd[] = {
	BT_DATA(BT_DATA_NAME_COMPLETE, CONFIG_BT_DEVICE_NAME, sizeof(CONFIG_BT_DEVICE_NAME) - 1),
};

int main(void)
{
	struct bt_le_per_adv_sync_transfer_param past_param;
	int err;

	printk("Starting Peripheral Periodic Advertising Synchronization Transfer (PAST) Demo\n");

	/* Initialize the Bluetooth Subsystem */
	err = bt_enable(NULL);
	if (err) {
		printk("Bluetooth init failed (err %d)\n", err);
		return 0;
	}

	printk("Connection callbacks register...");
	bt_conn_cb_register(&conn_callbacks);
	printk("Success\n");

	printk("Periodic Advertising callbacks register...");
	bt_le_per_adv_sync_cb_register(&sync_callbacks);
	printk("Success.\n");

	printk("Subscribing to periodic advertising sync transfers\n");
	past_param.skip = 1;
	past_param.timeout = 1000; /* 10 seconds */
	err = bt_le_per_adv_sync_transfer_subscribe(NULL /* any peer */,
						    &past_param);
	if (err) {
		printk("PAST subscribe failed (err %d)\n", err);
		return 0;
	}

	err = bt_le_adv_start(BT_LE_ADV_CONN_FAST_1, NULL, 0, sd, ARRAY_SIZE(sd));
	if (err) {
		printk("Advertising failed to start (err %d)\n", err);
		return 0;
	}

	do {
		printk("Waiting for periodic sync...\n");
		err = k_sem_take(&sem_per_sync, K_FOREVER);
		if (err) {
			printk("failed (err %d)\n", err);
			return 0;
		}
		printk("Periodic sync established.\n");

		printk("Waiting for periodic sync lost...\n");
		err = k_sem_take(&sem_per_sync_lost, K_FOREVER);
		if (err) {
			printk("failed (err %d)\n", err);
			return 0;
		}
		printk("Periodic sync lost.\n");
	} while (true);
	return 0;
}