/*
 * Copyright (c) 2020 Cisco and/or its affiliates.
 * Licensed 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 __included_hicn_hs_h__
#define __included_hicn_hs_h__

#include "producer_dpo.h"
#include "hicn_buffer.h"

#include <vnet/session/application_interface.h>
#include <vnet/session/transport.h>

#include <vppinfra/lock.h>
#include <vppinfra/tw_timer_1t_3w_1024sl_ov.h>
#include <vppinfra/bihash_24_8.h>
#include <vnet/crypto/crypto.h>
#include <vppinfra/lock.h>


/* Log levels
 * 1 - errors
 * 2 - connection/stream events
 * 3 - packet events
 * 4 - timer events
 **/

#define HICN_HS_DEBUG               1
#define HICN_HS_TSTAMP_RESOLUTION  0.001	/* HICN_HS tick resolution (1ms) */
#define HICN_HS_TIMER_HANDLE_INVALID ((u32) ~0)
#define HICN_HS_SESSION_INVALID ((u32) ~0 - 1)
#define HICN_HS_MAX_PACKET_SIZE 1280

#define HICN_HS_INT_MAX  0x3FFFFFFFFFFFFFFF
#define HICN_HS_DEFAULT_FIFO_SIZE (64 << 10)
#define HICN_HS_DEFAULT_CONN_TIMEOUT (30 * 1000)	/* 30 seconds */
#define HICN_HS_SEND_PACKET_VEC_SIZE 16
#define HICN_HS_IV_LEN 17

#define HICN_HS_INPUT4_NODE_NAME "hicn_hs-input4"
#define HICN_HS_OUTPUT4_NODE_NAME "hicn_hs-output4"

#define HICN_HS_INPUT6_NODE_NAME "hicn_hs-input6"
#define HICN_HS_OUTPUT6_NODE_NAME "hicn_hs-output6"

#define HICN_HS_INPUT_INTEREST_NODE_NAME "hicn_hs-input-interest"
#define HICN_HS_INPUT_DATA_NODE_NAME "hicn_hs-input-data"

#define HICN_HS_DEFAULT_MTU (1500 - 40 - 20)

#define PROTO_DATA_SIZE 32
#define HICN_HS_PEND_INT_SIZE (1 << 11)
#define HICN_HS_PEND_INT_MASK (HICN_HS_PEND_INT_SIZE - 1)

#if HICN_HS_DEBUG
#define HICN_HS_DBG(_lvl, _fmt, _args...)   \
  if (_lvl <= HICN_HS_DEBUG)                \
    clib_warning (_fmt, ##_args)
#else
#define HICN_HS_DBG(_lvl, _fmt, _args...)
#endif

#if CLIB_ASSERT_ENABLE
#define HICN_HS_ASSERT(truth) ASSERT (truth)
#else
#define HICN_HS_ASSERT(truth)                        	\
  do {                                            	\
    if (PREDICT_FALSE (! (truth)))                	\
      HICN_HS_ERR ("ASSERT(%s) failed", # truth);    	\
  } while (0)
#endif

#define HICN_HS_ERR(_fmt, _args...)                	\
  do {                                          	\
    clib_warning ("HICN_HS-ERR: " _fmt, ##_args);  	\
  } while (0)

extern vlib_node_registration_t hicn_hs_input_node;
extern vlib_node_registration_t hicn_hs_input_interest_node;
extern vlib_node_registration_t hicn_hs_input_data_node;

typedef enum
{
#define hicn_hs_error(n,s) HICN_HS_ERROR_##n,
#include "errors/hicn_hs.def"
#undef hicn_hs_error
  HICN_HS_N_ERROR,
} hicn_hs_error_t;

typedef struct hicn_hs_proto_ hicn_hs_proto_t;

/* hicn configuration flags */
#define foreach_hicn_hs_cfg_flag 			\
  _(NO_CSUM_OFFLOAD, "No csum offload")    	\
  _(NO_TSO, "TSO off")

typedef enum hicn_hs_cfg_flag_bits_
{
#define _(sym, str) HICN_HS_CFG_F_##sym##_BIT,
  foreach_hicn_hs_cfg_flag
#undef _
  HICN_HS_CFG_N_FLAG_BITS
} hicn_hs_cfg_flag_bits_e;

typedef enum hicn_hs_cfg_flag_
{
#define _(sym, str) HICN_HS_CFG_F_##sym = 1 << HICN_HS_CFG_F_##sym##_BIT,
  foreach_hicn_hs_cfg_flag
#undef _
  HICN_HS_CFG_N_FLAGS
} hicn_hs_cfg_flags_e;

typedef enum hicn_hs_proto_event_
{
  PROTO_N_EVENT,
} hicn_hs_proto_event_t;

typedef struct hicn_hs_ctx_
{
  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
  transport_connection_t connection;		/* Must be first, for convenient casts!!! */
  u32 parent_app_wrk_id;
  u32 client_opaque;
  u32 timer_handle;
  u8 cfg_flags;					/**< Hicn ctx configuration flags */
  hicn_hs_proto_t *hs_proto;
  u8 hs_proto_data[PROTO_DATA_SIZE];

  /* Maps interest suffix -> vlib buffer index */
  u32 *pending_interests;

  // The hicn name for the consumer session
  hicn_name_t consumer_name;
  // The current name in production in th eproducer session
  hicn_name_t current_production_name;

  // The prefix for the producer names.
  /* XXX To be retrieved from a pool of names configured by the control protocol / network admin */
  fib_prefix_t producer_prefix;

  /* Store the size of the content currently produced. */
  u32 current_content_size;
  u32 number_of_segments;

  /* Store size of content to download - consumer side */
  u32 download_content_size;

  u32 bytes_produced;

  /* Seq number to assign to next segment */
  u32 snd_nxt;

  /* Expected bytes */
  u32 rcv_nxt;

  /* Some stats */
  u64 int_in;
  u64 data_in;
  u64 int_out;
  u64 data_out;
  u64 bytes_in;
  u64 bytes_outs;

  /* The DPO for this hicn_hs ctx */
  dpo_id_t dpo;

  /* Hash table for exact match prefix-suffix */
  clib_bihash_24_8_t output_buffer;

  /* Unused listener session index */
  u32 session_index;

  u8 running;
  u8 accepted;

  u16 mss;
} hicn_hs_ctx_t;

typedef clib_bihash_kv_24_8_t obuffer_kv4_t;

typedef struct {
  u32 ctx_index;
  u8 is_interest;
  u8 is_ip4;
  u8 flush;
  u32 seq_number;
  hicn_type_t type; 
} hicn_hs_buffer_t;

#define hicn_hs_buffer(b) ((hicn_hs_buffer_t *) (b)->opaque2)
#define hicn_buffer_hdr(b) ((hicn_header_t *) (vlib_buffer_get_current(b)))

always_inline void *
hicn_hs_proto_data(hicn_hs_ctx_t *ctx)
{
  return (void*)(ctx->hs_proto_data);
}

struct hicn_hs_proto_
{
  u32 (*init) (hicn_hs_ctx_t * hc);
  u32 (*rcv_data) (hicn_hs_ctx_t * hc, u16 n_data);
  u32 (*rcv_interest) (hicn_hs_ctx_t * hc);
  u32 (*on_interest_timeout) (hicn_hs_ctx_t *hc);
  u32 (*event) (hicn_hs_ctx_t *hc, hicn_hs_proto_event_t event);
  struct {
    u8 is_stream;
  } options;
};

typedef struct hicn_hs_worker_ctx_
{
  CLIB_CACHE_LINE_ALIGN_MARK (cacheline0);
  hicn_hs_ctx_t *hicn_ctxs;		   	   /**< worker's pool of hicn context */
  u32 next_hicn_ctx;				   /**< Next hicn context, to be used in start_listen*/
  int64_t time_now;				   /**< worker time */
  tw_timer_wheel_1t_3w_1024sl_ov_t timer_wheel;	   /**< worker timer wheel */
  vlib_main_t *vm;				   /**< pointer to thread's vlib main*/
  /** Peekers rw lock */
  clib_rwlock_t peekers_rw_locks;
} hicn_hs_worker_t;

typedef struct hicn_hs_configuration_
{
  /** Max rx fifo size for a session (in bytes). It is used in to compute the
   *  rfc 7323 window scaling factor */
  u32 max_rx_fifo;

  /** Min rx fifo for a session (in bytes) */
  u32 min_rx_fifo;

  /** Default MTU to be used when establishing connections */
  u16 default_mtu;

  /** Enable tx pacing for new connections */
  u8 enable_tx_pacing;

  /** Allow use of TSO whenever available */
  u8 allow_tso;

  /** Set if csum offloading is enabled */
  u8 csum_offload;

  /** Timer ticks to wait for close from app */
  u16 closewait_time;

  /** Time to wait (sec) before cleaning up the connection */
  f32 cleanup_time;
} hicn_hs_configuration_t;

typedef struct _hicn_hs_lookup_dispatch
{
  u8 next, error;
} hicn_hs_lookup_dispatch_t;

#define foreach_hicn_hs_packet                 	\
  _ (DATA, "data")				\
  _ (INTEREST, "interest")			\
  _ (NO_HICN, "ho hicn")

typedef enum _hicn_hs_packet
{
  #define _(n, s) HICN_HS_##n,
  foreach_hicn_hs_packet
  #undef _
  HICN_HS_N_PACKET,
} hicn_hs_packet_t;

typedef struct hicn_hs_main_
{
  u32 app_index;
  hicn_hs_worker_t *workers;
  clib_bihash_24_8_t connection_hash;	/**< connection id -> conn handle */
  f64 tstamp_ticks_per_clock;

  // The new registered transport ID
  transport_proto_t transport_protocol_id;

  // Input/Output nodes information
  u32 hicn_hs_in4_idx;
  u32 hicn_hs_on4_idx;
  u32 hicn_hs_in6_idx;
  u32 hicn_hs_on6_idx;

  // Enabled/Disabled
  u8 enabled;

  u32 udp_fifo_size;
  u32 udp_fifo_prealloc;
  u32 connection_timeout;

  // Configuration
  hicn_hs_configuration_t cfg;

  // Dispatch table
  hicn_hs_lookup_dispatch_t dispatch_table[HICN_HS_N_PACKET];
} hicn_hs_main_t;

void hicn_hs_init (vlib_main_t * vm);

extern hicn_hs_main_t hicn_hs_main;
extern vlib_node_registration_t hicn_hs_input4_node;
extern vlib_node_registration_t hicn_hs_output4_node;
extern vlib_node_registration_t hicn_hs_input6_node;
extern vlib_node_registration_t hicn_hs_output6_node;
extern char *hicn_hs_error_strings[];

#define hicn_hs_cfg (hicn_hs_main.cfg)

// Protocols
extern hicn_hs_proto_t cbr_proto;

always_inline
hicn_hs_main_t *hicn_hs_get_main ()
{
  return &hicn_hs_main;
}

always_inline
transport_proto_t hicn_hs_get_protocol_id()
{
  hicn_hs_main_t *hm = hicn_hs_get_main ();
  return hm->transport_protocol_id;
}

clib_error_t * hicn_hs_enable_disable(vlib_main_t * vm, u8 is_en);

always_inline void
hicn_hs_update_transport(hicn_hs_ctx_t *ctx, u16 recv_data)
{
  // Pass data packet to transport
  ctx->hs_proto->rcv_data(ctx, recv_data);
}

always_inline void
hicn_hs_set_next_prod_size (hicn_hs_ctx_t *ctx, u32 prod_size)
{
  ctx->current_content_size = prod_size;
  ctx->number_of_segments = (prod_size / ctx->mss) + ((prod_size % ctx->mss) > 0);
}

always_inline hicn_hs_worker_t *
hicn_hs_get_worker_by_context (hicn_hs_ctx_t *ctx)
{
  hicn_hs_main_t *hmm = hicn_hs_get_main ();
  return &hmm->workers[ctx->c_thread_index];
}

always_inline hicn_hs_worker_t *
hicn_hs_get_worker_by_thread (u32 thread_idx)
{
  hicn_hs_main_t *hmm = hicn_hs_get_main ();
  return &hmm->workers[thread_idx];
}

always_inline hicn_hs_ctx_t *
hicn_hs_wrk_get_ctx(hicn_hs_worker_t *wrk, u32 index)
{
  return pool_elt_at_index (wrk->hicn_ctxs, index);
}

always_inline u32
hicn_hs_wrk_get_next_ctx_index(hicn_hs_worker_t *wrk)
{
  return wrk->next_hicn_ctx++;
}

always_inline hicn_hs_ctx_t *
hicn_hs_get_ctx_by_index (u32 ctx_index, u32 thread_index)
{
  hicn_hs_worker_t *wrk = hicn_hs_get_worker_by_thread(thread_index);
  return hicn_hs_wrk_get_ctx(wrk, ctx_index);
}

always_inline hicn_name_t*
hicn_hs_ctx_get_consumer_name(hicn_hs_ctx_t *ctx)
{
  return &ctx->consumer_name;
}

always_inline dpo_id_t*
hicn_hs_ctx_get_dpo(hicn_hs_ctx_t *ctx)
{
  return &ctx->dpo;
}

#endif /* __included_hicn_hs_h__ */

/*
 * fd.io coding-style-patch-verification: ON
 *
 * Local Variables:
 * eval: (c-set-style "gnu")
 * End:
 */