/*
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *  http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing,
 * software distributed under the License is distributed on an
 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
 * KIND, either express or implied.  See the License for the
 * specific language governing permissions and limitations
 * under the License.
 */

#ifndef H_BLE_
#define H_BLE_

/**
 * @defgroup bt_low_energy Bluetooth Low Energy
 * @{
 */

#include <inttypes.h>
#include <string.h>
#include "syscfg/syscfg.h"
#include "os/os.h"

#ifdef __cplusplus
extern "C" {
#endif

/** The number of advertising instances */
#define BLE_ADV_INSTANCES    (MYNEWT_VAL(BLE_MULTI_ADV_INSTANCES) + 1)

/** BLE encryption block definitions */
#define BLE_ENC_BLOCK_SIZE       (16)

/** 4 byte header + 251 byte payload. */
#define BLE_ACL_MAX_PKT_SIZE     255

/**
 * @cond INTERNAL_DOCS
 */
struct ble_encryption_block
{
    uint8_t     key[BLE_ENC_BLOCK_SIZE];
    uint8_t     plain_text[BLE_ENC_BLOCK_SIZE];
    uint8_t     cipher_text[BLE_ENC_BLOCK_SIZE];
};

/*
 * BLE MBUF structure:
 *
 * The BLE mbuf structure is as follows. Note that this structure applies to
 * the packet header mbuf (not mbufs that are part of a "packet chain"):
 *      struct os_mbuf          (16)
 *      struct os_mbuf_pkthdr   (8)
 *      struct ble_mbuf_hdr     (8)
 *      Data buffer             (payload size, in bytes)
 *
 * The BLE mbuf header contains the following:
 *  flags: bitfield with the following values
 *      0x01:   Set if there was a match on the whitelist
 *      0x02:   Set if a connect request was transmitted upon receiving pdu
 *      0x04:   Set the first time we transmit the PDU (used to detect retry).
 *  channel: The logical BLE channel PHY channel # (0 - 39)
 *  crcok: flag denoting CRC check passed (1) or failed (0).
 *  rssi: RSSI, in dBm.
 */
struct ble_mbuf_hdr_rxinfo
{
    uint16_t flags;
    uint8_t channel;
    uint8_t handle;
    int8_t  rssi;
    /* XXX: we could just use single phy_mode field */
    int8_t  phy;
    uint8_t phy_mode;
#if MYNEWT_VAL(BLE_LL_CFG_FEAT_LL_PRIVACY)
    int8_t  rpa_index;
#endif
#if MYNEWT_VAL(BLE_LL_CFG_FEAT_LL_EXT_ADV)
    void *user_data;
#endif
};

/*
 * Flag definitions for rxinfo
 *
 * Note: it's ok to have symbols with the same values as long as they cannot be
 *       set for the same PDU (e.g. one use by scanner, other one used by
 *       connection)
 */
#define BLE_MBUF_HDR_F_CONNECT_IND_TXD  (0x4000)
#define BLE_MBUF_HDR_F_CONNECT_REQ_TXD  (0x4000)
#define BLE_MBUF_HDR_F_CONNECT_RSP_RXD  (0x0008)
#define BLE_MBUF_HDR_F_CONN_CREDIT      (0x8000)
#define BLE_MBUF_HDR_F_IGNORED          (0x8000)
#define BLE_MBUF_HDR_F_CONN_CREDIT_INT  (0x4000)
#define BLE_MBUF_HDR_F_SCAN_REQ_TXD     (0x4000)
#define BLE_MBUF_HDR_F_INITA_RESOLVED   (0x2000)
#define BLE_MBUF_HDR_F_TARGETA_RESOLVED (0x2000)
#define BLE_MBUF_HDR_F_EXT_ADV_SEC      (0x1000)
#define BLE_MBUF_HDR_F_EXT_ADV          (0x0800)
#define BLE_MBUF_HDR_F_RESOLVED         (0x0400)
#define BLE_MBUF_HDR_F_AUX_PTR_WAIT     (0x0200)
#define BLE_MBUF_HDR_F_AUX_PTR_FAILED   (0x0100)
#define BLE_MBUF_HDR_F_CRC_OK           (0x0080)
#define BLE_MBUF_HDR_F_DEVMATCH         (0x0040)
#define BLE_MBUF_HDR_F_MIC_FAILURE      (0x0020)
#define BLE_MBUF_HDR_F_SCAN_RSP_TXD     (0x0010)
#define BLE_MBUF_HDR_F_SCAN_RSP_RXD     (0x0008)
#define BLE_MBUF_HDR_F_RXSTATE_MASK     (0x0007)

/* Transmit info. NOTE: no flags defined */
struct ble_mbuf_hdr_txinfo
{
    uint8_t flags;
    uint8_t hdr_byte;
    uint16_t offset;
    uint16_t pyld_len;
};

struct ble_mbuf_hdr_txiso {
    uint16_t packet_seq_num;
};

/**
 * @endcond
 */

/** Structure representing a BLE mbuf header. */
struct ble_mbuf_hdr
{
    union {
        /** RX info for received packets. */
        struct ble_mbuf_hdr_rxinfo rxinfo;

        /** TX info for transmitted packets. */
        struct ble_mbuf_hdr_txinfo txinfo;

        /** TX ISO info for transmitted isochronous packets. */
        struct ble_mbuf_hdr_txiso txiso;
    };

    /** CPU time when the packet processing began. */
    uint32_t beg_cputime;

    /** Remaining microseconds for packet processing. */
    uint32_t rem_usecs;
};

/**
 * @cond INTERNAL_DOCS
 */
#define BLE_MBUF_HDR_IGNORED(hdr) \
    (!!((hdr)->rxinfo.flags & BLE_MBUF_HDR_F_IGNORED))

#define BLE_MBUF_HDR_SCAN_REQ_TXD(hdr) \
    (!!((hdr)->rxinfo.flags & BLE_MBUF_HDR_F_SCAN_REQ_TXD))

#define BLE_MBUF_HDR_EXT_ADV_SEC(hdr) \
    (!!((hdr)->rxinfo.flags & BLE_MBUF_HDR_F_EXT_ADV_SEC))

#define BLE_MBUF_HDR_EXT_ADV(hdr) \
    (!!((hdr)->rxinfo.flags & BLE_MBUF_HDR_F_EXT_ADV))

#define BLE_MBUF_HDR_DEVMATCH(hdr) \
    (!!((hdr)->rxinfo.flags & BLE_MBUF_HDR_F_DEVMATCH))

#define BLE_MBUF_HDR_SCAN_RSP_RXD(hdr) \
    (!!((hdr)->rxinfo.flags & BLE_MBUF_HDR_F_SCAN_RSP_RXD))

#define BLE_MBUF_HDR_WAIT_AUX(hdr)      \
    (!!((hdr)->rxinfo.flags & BLE_MBUF_HDR_F_AUX_PTR_WAIT))

#define BLE_MBUF_HDR_CRC_OK(hdr)        \
    (!!((hdr)->rxinfo.flags & BLE_MBUF_HDR_F_CRC_OK))

#define BLE_MBUF_HDR_MIC_FAILURE(hdr)   \
    (!!((hdr)->rxinfo.flags & BLE_MBUF_HDR_F_MIC_FAILURE))

#define BLE_MBUF_HDR_RESOLVED(hdr)      \
    (!!((hdr)->rxinfo.flags & BLE_MBUF_HDR_F_RESOLVED))

#define BLE_MBUF_HDR_INITA_RESOLVED(hdr)      \
    (!!((hdr)->rxinfo.flags & BLE_MBUF_HDR_F_INITA_RESOLVED))

#define BLE_MBUF_HDR_TARGETA_RESOLVED(hdr)      \
    (!!((hdr)->rxinfo.flags & BLE_MBUF_HDR_F_TARGETA_RESOLVED))

#define BLE_MBUF_HDR_RX_STATE(hdr)      \
    ((uint8_t)((hdr)->rxinfo.flags & BLE_MBUF_HDR_F_RXSTATE_MASK))

#define BLE_MBUF_HDR_PTR(om)            \
    (struct ble_mbuf_hdr *)((uint8_t *)om + sizeof(struct os_mbuf) + \
                            sizeof(struct os_mbuf_pkthdr))

/* BLE mbuf overhead per packet header mbuf */
#define BLE_MBUF_PKTHDR_OVERHEAD        \
    (sizeof(struct os_mbuf_pkthdr) + sizeof(struct ble_mbuf_hdr))

#define BLE_MBUF_MEMBLOCK_OVERHEAD      \
    (sizeof(struct os_mbuf) + BLE_MBUF_PKTHDR_OVERHEAD)

/* Length of host user header.  Only contains the peer's connection handle. */
#define BLE_MBUF_HS_HDR_LEN     (2)

/**
 * @endcond
 */

/** Length of a Bluetooth Device Address. */
#define BLE_DEV_ADDR_LEN        (6)

/**
 * @cond INTERNAL_DOCS
 */
extern uint8_t g_dev_addr[BLE_DEV_ADDR_LEN];
extern uint8_t g_random_addr[BLE_DEV_ADDR_LEN];

/* BLE Error Codes (Core v4.2 Vol 2 part D) */
enum ble_error_codes
{
    /* An "error" code of 0x0 means success */
    BLE_ERR_SUCCESS             = 0x00,
    BLE_ERR_UNKNOWN_HCI_CMD     = 0x01,
    BLE_ERR_UNK_CONN_ID         = 0x02,
    BLE_ERR_HW_FAIL             = 0x03,
    BLE_ERR_PAGE_TMO            = 0x04,
    BLE_ERR_AUTH_FAIL           = 0x05,
    BLE_ERR_PINKEY_MISSING      = 0x06,
    BLE_ERR_MEM_CAPACITY        = 0x07,
    BLE_ERR_CONN_SPVN_TMO       = 0x08,
    BLE_ERR_CONN_LIMIT          = 0x09,
    BLE_ERR_SYNCH_CONN_LIMIT    = 0x0a,
    BLE_ERR_ACL_CONN_EXISTS     = 0x0b,
    BLE_ERR_CMD_DISALLOWED      = 0x0c,
    BLE_ERR_CONN_REJ_RESOURCES  = 0x0d,
    BLE_ERR_CONN_REJ_SECURITY   = 0x0e,
    BLE_ERR_CONN_REJ_BD_ADDR    = 0x0f,
    BLE_ERR_CONN_ACCEPT_TMO     = 0x10,
    BLE_ERR_UNSUPPORTED         = 0x11,
    BLE_ERR_INV_HCI_CMD_PARMS   = 0x12,
    BLE_ERR_REM_USER_CONN_TERM  = 0x13,
    BLE_ERR_RD_CONN_TERM_RESRCS = 0x14,
    BLE_ERR_RD_CONN_TERM_PWROFF = 0x15,
    BLE_ERR_CONN_TERM_LOCAL     = 0x16,
    BLE_ERR_REPEATED_ATTEMPTS   = 0x17,
    BLE_ERR_NO_PAIRING          = 0x18,
    BLE_ERR_UNK_LMP             = 0x19,
    BLE_ERR_UNSUPP_REM_FEATURE  = 0x1a,
    BLE_ERR_SCO_OFFSET          = 0x1b,
    BLE_ERR_SCO_ITVL            = 0x1c,
    BLE_ERR_SCO_AIR_MODE        = 0x1d,
    BLE_ERR_INV_LMP_LL_PARM     = 0x1e,
    BLE_ERR_UNSPECIFIED         = 0x1f,
    BLE_ERR_UNSUPP_LMP_LL_PARM  = 0x20,
    BLE_ERR_NO_ROLE_CHANGE      = 0x21,
    BLE_ERR_LMP_LL_RSP_TMO      = 0x22,
    BLE_ERR_LMP_COLLISION       = 0x23,
    BLE_ERR_LMP_PDU             = 0x24,
    BLE_ERR_ENCRYPTION_MODE     = 0x25,
    BLE_ERR_LINK_KEY_CHANGE     = 0x26,
    BLE_ERR_UNSUPP_QOS          = 0x27,
    BLE_ERR_INSTANT_PASSED      = 0x28,
    BLE_ERR_UNIT_KEY_PAIRING    = 0x29,
    BLE_ERR_DIFF_TRANS_COLL     = 0x2a,
    /* BLE_ERR_RESERVED         = 0x2b */
    BLE_ERR_QOS_PARM            = 0x2c,
    BLE_ERR_QOS_REJECTED        = 0x2d,
    BLE_ERR_CHAN_CLASS          = 0x2e,
    BLE_ERR_INSUFFICIENT_SEC    = 0x2f,
    BLE_ERR_PARM_OUT_OF_RANGE   = 0x30,
    /* BLE_ERR_RESERVED         = 0x31 */
    BLE_ERR_PENDING_ROLE_SW     = 0x32,
    /* BLE_ERR_RESERVED         = 0x33 */
    BLE_ERR_RESERVED_SLOT       = 0x34,
    BLE_ERR_ROLE_SW_FAIL        = 0x35,
    BLE_ERR_INQ_RSP_TOO_BIG     = 0x36,
    BLE_ERR_SEC_SIMPLE_PAIR     = 0x37,
    BLE_ERR_HOST_BUSY_PAIR      = 0x38,
    BLE_ERR_CONN_REJ_CHANNEL    = 0x39,
    BLE_ERR_CTLR_BUSY           = 0x3a,
    BLE_ERR_CONN_PARMS          = 0x3b,
    BLE_ERR_DIR_ADV_TMO         = 0x3c,
    BLE_ERR_CONN_TERM_MIC       = 0x3d,
    BLE_ERR_CONN_ESTABLISHMENT  = 0x3e,
    BLE_ERR_MAC_CONN_FAIL       = 0x3f,
    BLE_ERR_COARSE_CLK_ADJ      = 0x40,
    BLE_ERR_TYPE0_SUBMAP_NDEF   = 0x41,
    BLE_ERR_UNK_ADV_INDENT      = 0x42,
    BLE_ERR_LIMIT_REACHED       = 0x43,
    BLE_ERR_OPERATION_CANCELLED = 0x44,
    BLE_ERR_PACKET_TOO_LONG     = 0x45,
    BLE_ERR_MAX                 = 0xff
};

/* HW error codes */
#define BLE_HW_ERR_DO_NOT_USE           (0) /* XXX: reserve this one for now */
#define BLE_HW_ERR_HCI_SYNC_LOSS        (1)

/**
 * @endcond
 */

/**
 * @defgroup ble_own_address_types Bluetooth Device Own Address Types
 * @{
 */

/** Bluetooth Device Own Address Type: Public. */
#define BLE_OWN_ADDR_PUBLIC                  (0x00)

/** Bluetooth Device Own Address Type: Random. */
#define BLE_OWN_ADDR_RANDOM                  (0x01)

/**
 * Bluetooth Device Own Address Type: Resolvable Private Address (RPA)
 * with Public fallback.
 */
#define BLE_OWN_ADDR_RPA_PUBLIC_DEFAULT      (0x02)

/**
 * Bluetooth Device Own Address Type: Resolvable Private Address (RPA)
 * with Random fallback.
 */
#define BLE_OWN_ADDR_RPA_RANDOM_DEFAULT      (0x03)

/** @} */

/**
 * @defgroup ble_address_types Bluetooth Device Address Types
 * @{
 */

/** Bluetooth Device Address Type: Public. */
#define BLE_ADDR_PUBLIC      (0x00)

/** Bluetooth Device Address Type: Random. */
#define BLE_ADDR_RANDOM      (0x01)

/**
 * Bluetooth Device Address Type: Public Identity Address
 * (Corresponds to Resolved Private Address).
 */
#define BLE_ADDR_PUBLIC_ID   (0x02)

/**
 * Bluetooth Device Address Type: Random (Static) Identity Address
 * (Corresponds to Resolved Private Address).
 */
#define BLE_ADDR_RANDOM_ID   (0x03)

/** @} */

/**
 * @brief A macro representing any BLE address.
 *
 * This macro initializes a `ble_addr_t` structure to all zeros.
 */
#define BLE_ADDR_ANY (&(ble_addr_t) { 0, {0, 0, 0, 0, 0, 0} })

/**
 * Checks if the given address is a Resolvable Private Address (RPA).
 *
 * @param addr              Pointer to the `ble_addr_t` structure.
 * @return                  Non-zero if the address is an RPA,
 *                          zero otherwise.
 */
#define BLE_ADDR_IS_RPA(addr)     (((addr)->type == BLE_ADDR_RANDOM) && \
                                   ((addr)->val[5] & 0xc0) == 0x40)

/**
 * Checks if the given address is a Non-Resolvable Private Address (NRPA).
 *
 * @param addr              Pointer to the `ble_addr_t` structure.
 * @return                  Non-zero if the address is an NRPA,
 *                          zero otherwise.
 */
#define BLE_ADDR_IS_NRPA(addr)    (((addr)->type == BLE_ADDR_RANDOM) && \
                                   ((addr)->val[5] & 0xc0) == 0x00)

/**
 * @brief Checks if the given address is a Static Random Address.
 *
 * @param addr              Pointer to the `ble_addr_t` structure.
 * @return                  Non-zero if the address is a Static Random Address,
 *                          zero otherwise.
 */
#define BLE_ADDR_IS_STATIC(addr)  (((addr)->type == BLE_ADDR_RANDOM) && \
                                   ((addr)->val[5] & 0xc0) == 0xc0)

/** Structure representing a BLE address. */
typedef struct {
    /** The type of the address. */
    uint8_t type;

    /** The value of the address as an array of 6 bytes. */
    uint8_t val[6];
} ble_addr_t;


static inline int ble_addr_cmp(const ble_addr_t *a, const ble_addr_t *b)
{
    int type_diff;

    type_diff = a->type - b->type;
    if (type_diff != 0) {
        return type_diff;
    }

    return memcmp(a->val, b->val, sizeof(a->val));
}

#ifdef __cplusplus
}
#endif

/** @} **/

#endif /* H_BLE_ */