/* att_internal.h - Attribute protocol handling */

/*
 * Copyright (c) 2015-2016 Intel Corporation
 *
 * SPDX-License-Identifier: Apache-2.0
 */

#define BT_ATT_DEFAULT_LE_MTU	23

#if BT_L2CAP_RX_MTU < CONFIG_BLUETOOTH_L2CAP_TX_MTU
#define BT_ATT_MTU BT_L2CAP_RX_MTU
#else
#define BT_ATT_MTU CONFIG_BLUETOOTH_L2CAP_TX_MTU
#endif

struct bt_att_hdr {
	u8_t  code;
} __packed;

#define BT_ATT_OP_ERROR_RSP			0x01
struct bt_att_error_rsp {
	u8_t  request;
	u16_t handle;
	u8_t  error;
} __packed;

#define BT_ATT_OP_MTU_REQ			0x02
struct bt_att_exchange_mtu_req {
	u16_t mtu;
} __packed;

#define BT_ATT_OP_MTU_RSP			0x03
struct bt_att_exchange_mtu_rsp {
	u16_t mtu;
} __packed;

/* Find Information Request */
#define BT_ATT_OP_FIND_INFO_REQ			0x04
struct bt_att_find_info_req {
	u16_t start_handle;
	u16_t end_handle;
} __packed;

/* Format field values for BT_ATT_OP_FIND_INFO_RSP */
#define BT_ATT_INFO_16				0x01
#define BT_ATT_INFO_128				0x02

struct bt_att_info_16 {
	u16_t handle;
	u16_t uuid;
} __packed;

struct bt_att_info_128 {
	u16_t handle;
	u8_t  uuid[16];
} __packed;

/* Find Information Response */
#define BT_ATT_OP_FIND_INFO_RSP			0x05
struct bt_att_find_info_rsp {
	u8_t  format;
	u8_t  info[0];
} __packed;

/* Find By Type Value Request */
#define BT_ATT_OP_FIND_TYPE_REQ			0x06
struct bt_att_find_type_req {
	u16_t start_handle;
	u16_t end_handle;
	u16_t type;
	u8_t  value[0];
} __packed;

struct bt_att_handle_group {
	u16_t start_handle;
	u16_t end_handle;
} __packed;

/* Find By Type Value Response */
#define BT_ATT_OP_FIND_TYPE_RSP			0x07
struct bt_att_find_type_rsp {
	struct bt_att_handle_group list[0];
} __packed;

/* Read By Type Request */
#define BT_ATT_OP_READ_TYPE_REQ			0x08
struct bt_att_read_type_req {
	u16_t start_handle;
	u16_t end_handle;
	u8_t  uuid[0];
} __packed;

struct bt_att_data {
	u16_t handle;
	u8_t  value[0];
} __packed;

/* Read By Type Response */
#define BT_ATT_OP_READ_TYPE_RSP			0x09
struct bt_att_read_type_rsp {
	u8_t  len;
	struct bt_att_data data[0];
} __packed;

/* Read Request */
#define BT_ATT_OP_READ_REQ			0x0a
struct bt_att_read_req {
	u16_t handle;
} __packed;

/* Read Response */
#define BT_ATT_OP_READ_RSP			0x0b
struct bt_att_read_rsp {
	u8_t  value[0];
} __packed;

/* Read Blob Request */
#define BT_ATT_OP_READ_BLOB_REQ			0x0c
struct bt_att_read_blob_req {
	u16_t handle;
	u16_t offset;
} __packed;

/* Read Blob Response */
#define BT_ATT_OP_READ_BLOB_RSP			0x0d
struct bt_att_read_blob_rsp {
	u8_t  value[0];
} __packed;

/* Read Multiple Request */
#define BT_ATT_READ_MULT_MIN_LEN_REQ		0x04

#define BT_ATT_OP_READ_MULT_REQ			0x0e
struct bt_att_read_mult_req {
	u16_t handles[0];
} __packed;

/* Read Multiple Respose */
#define BT_ATT_OP_READ_MULT_RSP			0x0f
struct bt_att_read_mult_rsp {
	u8_t  value[0];
} __packed;

/* Read by Group Type Request */
#define BT_ATT_OP_READ_GROUP_REQ		0x10
struct bt_att_read_group_req {
	u16_t start_handle;
	u16_t end_handle;
	u8_t  uuid[0];
} __packed;

struct bt_att_group_data {
	u16_t start_handle;
	u16_t end_handle;
	u8_t  value[0];
} __packed;

/* Read by Group Type Response */
#define BT_ATT_OP_READ_GROUP_RSP		0x11
struct bt_att_read_group_rsp {
	u8_t  len;
	struct bt_att_group_data data[0];
} __packed;

/* Write Request */
#define BT_ATT_OP_WRITE_REQ			0x12
struct bt_att_write_req {
	u16_t handle;
	u8_t  value[0];
} __packed;

/* Write Response */
#define BT_ATT_OP_WRITE_RSP			0x13

/* Prepare Write Request */
#define BT_ATT_OP_PREPARE_WRITE_REQ		0x16
struct bt_att_prepare_write_req {
	u16_t handle;
	u16_t offset;
	u8_t  value[0];
} __packed;

/* Prepare Write Respond */
#define BT_ATT_OP_PREPARE_WRITE_RSP		0x17
struct bt_att_prepare_write_rsp {
	u16_t handle;
	u16_t offset;
	u8_t  value[0];
} __packed;

/* Execute Write Request */
#define BT_ATT_FLAG_CANCEL			0x00
#define BT_ATT_FLAG_EXEC			0x01

#define BT_ATT_OP_EXEC_WRITE_REQ		0x18
struct bt_att_exec_write_req {
	u8_t  flags;
} __packed;

/* Execute Write Response */
#define BT_ATT_OP_EXEC_WRITE_RSP		0x19

/* Handle Value Notification */
#define BT_ATT_OP_NOTIFY			0x1b
struct bt_att_notify {
	u16_t handle;
	u8_t  value[0];
} __packed;

/* Handle Value Indication */
#define BT_ATT_OP_INDICATE			0x1d
struct bt_att_indicate {
	u16_t handle;
	u8_t  value[0];
} __packed;

/* Handle Value Confirm */
#define BT_ATT_OP_CONFIRM			0x1e

struct bt_att_signature {
	u8_t  value[12];
} __packed;

/* Write Command */
#define BT_ATT_OP_WRITE_CMD			0x52
struct bt_att_write_cmd {
	u16_t handle;
	u8_t  value[0];
} __packed;

/* Signed Write Command */
#define BT_ATT_OP_SIGNED_WRITE_CMD		0xd2
struct bt_att_signed_write_cmd {
	u16_t handle;
	u8_t  value[0];
} __packed;

void bt_att_init(void);
u16_t bt_att_get_mtu(struct bt_conn *conn);
struct net_buf *bt_att_create_pdu(struct bt_conn *conn, u8_t op,
				  size_t len);

/* Send ATT PDU over a connection */
int bt_att_send(struct bt_conn *conn, struct net_buf *buf);

/* Send ATT Request over a connection */
int bt_att_req_send(struct bt_conn *conn, struct bt_att_req *req);

/* Cancel ATT request */
void bt_att_req_cancel(struct bt_conn *conn, struct bt_att_req *req);