/*  Bluetooth Mesh */

/*
 * Copyright (c) 2017 Intel Corporation
 *
 * SPDX-License-Identifier: Apache-2.0
 */
#ifndef _MESH_NET_H_
#define _MESH_NET_H_

#define BT_MESH_NET_FLAG_KR BIT(0)
#define BT_MESH_NET_FLAG_IVU BIT(1)

#define BT_MESH_KR_NORMAL 0x00
#define BT_MESH_KR_PHASE_1 0x01
#define BT_MESH_KR_PHASE_2 0x02
#define BT_MESH_KR_PHASE_3 0x03

#define BT_MESH_IV_UPDATE(flags) ((flags >> 1) & 0x01)
#define BT_MESH_KEY_REFRESH(flags) (flags & 0x01)

/* How many hours in between updating IVU duration */
#define BT_MESH_IVU_MIN_HOURS 96
#define BT_MESH_IVU_HOURS (BT_MESH_IVU_MIN_HOURS / CONFIG_BT_MESH_IVU_DIVIDER)
#define BT_MESH_IVU_TIMEOUT K_HOURS(BT_MESH_IVU_HOURS)

#define BT_MESH_NET_MAX_PDU_LEN 29

#if defined(CONFIG_BT_MESH_RELAY_SRC_DBG)
struct net_buf_trace_t {
    void *buf;
    u8_t addr[12];
};
extern struct net_buf_trace_t net_buf_trace;
#endif

struct bt_mesh_app_key {
    u16_t net_idx;
    u16_t app_idx;
    bool updated;
    bool appkey_active;

    struct bt_mesh_app_keys {
        u8_t id;
        u8_t val[16];
    } keys[2];
};

struct bt_mesh_subnet {
    bt_u32_t beacon_sent; /* Timestamp of last sent beacon */
    u8_t beacons_last; /* Number of beacons during last
				   * observation window
				   */
    u8_t beacons_cur; /* Number of beaconds observed during
				   * currently ongoing window.
				   */

    u8_t beacon_cache[21]; /* Cached last authenticated beacon */

    u16_t net_idx; /* NetKeyIndex */

    bool kr_flag; /* Key Refresh Flag */
    u8_t kr_phase; /* Key Refresh Phase */

    u8_t node_id; /* Node Identity State */
    bt_u32_t node_id_start; /* Node Identity started timestamp */

    u8_t auth[8]; /* Beacon Authentication Value */

    bool subnet_active;

    struct bt_mesh_subnet_keys {
        u8_t net[16]; /* NetKey */
        u8_t nid; /* NID */
        u8_t enc[16]; /* EncKey */
        u8_t net_id[8]; /* Network ID */
#if defined(CONFIG_BT_MESH_GATT_PROXY)
        u8_t identity[16]; /* IdentityKey */
#endif
        u8_t privacy[16]; /* PrivacyKey */
        u8_t beacon[16]; /* BeaconKey */
    } keys[2];
};

struct bt_mesh_rpl {
    u16_t src;
    bool old_iv;
#if defined(CONFIG_BT_SETTINGS)
    bool store;
#endif
    bt_u32_t seq;
};

#if defined(CONFIG_BT_MESH_FRIEND)
#define FRIEND_SEG_RX CONFIG_BT_MESH_FRIEND_SEG_RX
#define FRIEND_SUB_LIST_SIZE CONFIG_BT_MESH_FRIEND_SUB_LIST_SIZE
#else
#define FRIEND_SEG_RX 0
#define FRIEND_SUB_LIST_SIZE 0
#endif

struct bt_mesh_friend {
    u16_t lpn;
    u8_t recv_delay;
    u8_t fsn:1, send_last:1, pending_req:1, sec_update:1, pending_buf:1, valid:1, established:1;
    bt_s32_t poll_to;
    u8_t num_elem;
    u16_t lpn_counter;
    u16_t counter;

    u16_t net_idx;

    u16_t sub_list[FRIEND_SUB_LIST_SIZE];

    struct k_delayed_work timer;

    struct bt_mesh_friend_seg {
        sys_slist_t queue;
    } seg[FRIEND_SEG_RX];

    struct net_buf *last;

    sys_slist_t queue;
    bt_u32_t queue_size;

    /* Friend Clear Procedure */
    struct {
        bt_u32_t start; /* Clear Procedure start */
        u16_t frnd; /* Previous Friend's address */
        u16_t repeat_sec; /* Repeat timeout in seconds */
        struct k_delayed_work timer; /* Repeat timer */
    } clear;
};

#if defined(CONFIG_BT_MESH_LOW_POWER)
#define LPN_GROUPS CONFIG_BT_MESH_LPN_GROUPS
#else
#define LPN_GROUPS 0
#endif

/* Low Power Node state */
struct bt_mesh_lpn {
    enum __packed {
        BT_MESH_LPN_DISABLED, /* LPN feature is disabled */
        BT_MESH_LPN_CLEAR, /* Clear in progress */
        BT_MESH_LPN_TIMER, /* Waiting for auto timer expiry */
        BT_MESH_LPN_ENABLED, /* LPN enabled, but no Friend */
        BT_MESH_LPN_REQ_WAIT, /* Wait before scanning for offers */
        BT_MESH_LPN_WAIT_OFFER, /* Friend Req sent */
        BT_MESH_LPN_ESTABLISHED, /* Friendship established */
        BT_MESH_LPN_RECV_DELAY, /* Poll sent, waiting ReceiveDelay */
        BT_MESH_LPN_WAIT_UPDATE, /* Waiting for Update or message */
    } state;

    /* Transaction Number (used for subscription list) */
    u8_t xact_next;
    u8_t xact_pending;
    u8_t sent_req;

    /* Address of our Friend when we're a LPN. Unassigned if we don't
	 * have a friend yet.
	 */
    u16_t frnd;

    /* Value from the friend offer */
    u8_t recv_win;

    u8_t req_attempts; /* Number of Request attempts */

    bt_s32_t poll_timeout;

    u8_t groups_changed:1, /* Friend Subscription List needs updating */
        pending_poll:1, /* Poll to be sent after subscription */
        disable:1, /* Disable LPN after clearing */
        fsn:1, /* Friend Sequence Number */
        established:1, /* Friendship established */
        clear_success:1; /* Friend Clear Confirm received */

    /* Friend Queue Size */
    u8_t queue_size;

    /* LPNCounter */
    u16_t counter;

    /* Previous Friend of this LPN */
    u16_t old_friend;

    /* Duration reported for last advertising packet */
    u16_t adv_duration;

    /* Next LPN related action timer */
    struct k_delayed_work timer;

    /* Subscribed groups */
    u16_t groups[LPN_GROUPS];

    /* Bit fields for tracking which groups the Friend knows about */
    ATOMIC_DEFINE(added, LPN_GROUPS);
    ATOMIC_DEFINE(pending, LPN_GROUPS);
    ATOMIC_DEFINE(to_remove, LPN_GROUPS);
};

/* bt_mesh_net.flags */
enum {
    BT_MESH_VALID, /* We have been provisioned */
    BT_MESH_SUSPENDED, /* Network is temporarily suspended */
    BT_MESH_IVU_IN_PROGRESS, /* IV Update in Progress */
    BT_MESH_IVU_INITIATOR, /* IV Update initiated by us */
    BT_MESH_IVU_TEST, /* IV Update test mode */
    BT_MESH_IVU_PENDING, /* Update blocked by SDU in progress */

    /* pending storage actions */
    BT_MESH_RPL_PENDING,
    BT_MESH_KEYS_PENDING,
    BT_MESH_NET_PENDING,
    BT_MESH_IV_PENDING,
    BT_MESH_SEQ_PENDING,
    BT_MESH_HB_PUB_PENDING,
    BT_MESH_CFG_PENDING,
    BT_MESH_MOD_PENDING,

#ifdef CONFIG_BT_MESH_PROVISIONER
    BT_MESH_PROV_NODE_PENDING,
#endif

    /* Don't touch - intentionally last */
    BT_MESH_FLAG_COUNT,
};

struct bt_mesh_net {
    bt_u32_t iv_index; /* Current IV Index */
    bt_u32_t seq:24, /* Next outgoing sequence number */
        iv_update:1, /* 1 if IV Update in Progress */
        ivu_initiator:1, /* IV Update initiated by us */
        ivu_test:1, /* IV Update test mode */
        pending_update:1, /* Update blocked by SDU in progress */
        valid:1; /* 0 if unused */

    ATOMIC_DEFINE(flags, BT_MESH_FLAG_COUNT);
    s64_t last_update; /* Time since last IV Update change */

    /* Local network interface */
    struct k_work local_work;
    sys_slist_t local_queue;

#if defined(CONFIG_BT_MESH_FRIEND)
    /* Friend state, unique for each LPN that we're Friends for */
    struct bt_mesh_friend frnd[CONFIG_BT_MESH_FRIEND_LPN_COUNT];
#endif

#if defined(CONFIG_BT_MESH_LOW_POWER)
    struct bt_mesh_lpn lpn; /* Low Power Node state */
#endif

    /* Number of hours in current IV Update state */
    u8_t ivu_duration;

    /* Timer to track duration in current IV Update state */
    struct k_delayed_work ivu_timer;

    u8_t dev_key[16];

    struct bt_mesh_app_key app_keys[CONFIG_BT_MESH_APP_KEY_COUNT];

    struct bt_mesh_subnet sub[CONFIG_BT_MESH_SUBNET_COUNT];

    struct bt_mesh_rpl rpl[CONFIG_BT_MESH_CRPL];

#ifdef CONFIG_BT_MESH_PROVISIONER
    /* Provisioner and node share arguments from 'iv_index' to 'local_queue' + 'ivu_complete' */

    /* Application keys stored by provisioner */
    // struct bt_mesh_app_key p_app_keys[CONFIG_BT_MESH_PROVISIONER_APP_KEY_COUNT];

    /* Next app_idx can be assigned */
    u16_t p_app_idx_next;

    /* Network keys stored by provisioner */
    // struct bt_mesh_subnet p_sub[CONFIG_BT_MESH_PROVISIONER_SUBNET_COUNT];

    /* Next net_idx can be assigned */
    u16_t p_net_idx_next;
#endif
};

/* Network interface */
enum bt_mesh_net_if {
    BT_MESH_NET_IF_ADV,
    BT_MESH_NET_IF_LOCAL,
    BT_MESH_NET_IF_PROXY,
    BT_MESH_NET_IF_PROXY_CFG,
};

/* Decoding context for Network/Transport data */
struct bt_mesh_net_rx {
    struct bt_mesh_subnet *sub;
    struct bt_mesh_msg_ctx ctx;
    bt_u32_t seq; /* Sequence Number */
    u8_t old_iv:1, /* iv_index - 1 was used */
        new_key:1, /* Data was encrypted with updated key */
        friend_cred:1, /* Data was encrypted with friend cred */
        ctl:1, /* Network Control */
        net_if:2, /* Network interface */
        local_match:1, /* Matched a local element */
        friend_match:1; /* Matched an LPN we're friends for */
    s8_t rssi;
};

/* Encoding context for Network/Transport data */
struct bt_mesh_net_tx {
    struct bt_mesh_subnet *sub;
    struct bt_mesh_msg_ctx *ctx;
    u16_t src;
    u8_t xmit;
    u8_t friend_cred:1, aszmic:1, aid:6;
};

extern struct bt_mesh_net bt_mesh;
extern u16_t g_sub_list[CONFIG_BT_MESH_MODEL_GROUP_COUNT];

#define BT_MESH_NET_IVI_TX (bt_mesh.iv_index - atomic_test_bit(bt_mesh.flags, BT_MESH_IVU_IN_PROGRESS))
#define BT_MESH_NET_IVI_RX(rx) (bt_mesh.iv_index - (rx)->old_iv)

#define BT_MESH_NET_HDR_LEN 9

int bt_mesh_net_keys_create(struct bt_mesh_subnet_keys *keys, const u8_t key[16]);

int bt_mesh_net_create(u16_t idx, u8_t flags, const u8_t key[16], bt_u32_t iv_index);

u8_t bt_mesh_net_flags(struct bt_mesh_subnet *sub);

bool bt_mesh_kr_update(struct bt_mesh_subnet *sub, u8_t new_kr, bool new_key);

void bt_mesh_net_revoke_keys(struct bt_mesh_subnet *sub);

int bt_mesh_net_beacon_update(struct bt_mesh_subnet *sub);

void bt_mesh_rpl_reset(void);

bool bt_mesh_net_iv_update(bt_u32_t iv_index, bool iv_update);

void bt_mesh_net_sec_update(struct bt_mesh_subnet *sub);

struct bt_mesh_subnet *bt_mesh_subnet_get(u16_t net_idx);

struct bt_mesh_subnet *bt_mesh_subnet_find(const u8_t net_id[8], u8_t flags, bt_u32_t iv_index, const u8_t auth[8],
                                           bool *new_key);

int bt_mesh_net_encode(struct bt_mesh_net_tx *tx, struct net_buf_simple *buf, bool proxy);

int bt_mesh_net_send(struct bt_mesh_net_tx *tx, struct net_buf *buf, const struct bt_mesh_send_cb *cb, void *cb_data);

int bt_mesh_net_resend(struct bt_mesh_subnet *sub, struct net_buf *buf, bool new_key, const struct bt_mesh_send_cb *cb,
                       void *cb_data);

int bt_mesh_net_decode(struct net_buf_simple *data, enum bt_mesh_net_if net_if, struct bt_mesh_net_rx *rx,
                       struct net_buf_simple *buf);

void bt_mesh_net_recv(struct net_buf_simple *data, s8_t rssi, enum bt_mesh_net_if net_if);

bt_u32_t bt_mesh_next_seq(void);

void bt_mesh_net_start(void);

void bt_mesh_net_init(void);

/* Friendship Credential Management */
struct friend_cred {
    u16_t net_idx;
    u16_t addr;

    u16_t lpn_counter;
    u16_t frnd_counter;

    struct {
        u8_t nid; /* NID */
        u8_t enc[16]; /* EncKey */
        u8_t privacy[16]; /* PrivacyKey */
    } cred[2];
};

int friend_cred_get(struct bt_mesh_subnet *sub, u16_t addr, u8_t *nid, const u8_t **enc, const u8_t **priv);
int friend_cred_set(struct friend_cred *cred, u8_t idx, const u8_t net_key[16]);
void friend_cred_refresh(u16_t net_idx);
int friend_cred_update(struct bt_mesh_subnet *sub);
struct friend_cred *friend_cred_create(struct bt_mesh_subnet *sub, u16_t addr, u16_t lpn_counter, u16_t frnd_counter);
void friend_cred_clear(struct friend_cred *cred);
int friend_cred_del(u16_t net_idx, u16_t addr);

#endif