/*
 * Copyright (c) 2022 Huawei Technologies Co.,Ltd.
 *
 * openGauss is licensed under Mulan PSL v2.
 * You can use this software according to the terms and conditions of the Mulan PSL v2.
 * You may obtain a copy of Mulan PSL v2 at:
 *
 *          http://license.coscl.org.cn/MulanPSL2
 *
 * THIS SOFTWARE IS PROVIDED ON AN "AS IS" BASIS, WITHOUT WARRANTIES OF ANY KIND,
 * EITHER EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO NON-INFRINGEMENT,
 * MERCHANTABILITY OR FIT FOR A PARTICULAR PURPOSE.
 * See the Mulan PSL v2 for more details.
 * -------------------------------------------------------------------------
 *
 * srv_session.h
 *    header file for session-related functions
 *
 * IDENTIFICATION
 *    src/server/srv_session.h
 *
 * -------------------------------------------------------------------------
 */
#ifndef __SRV_SESSION_H__
#define __SRV_SESSION_H__

#include "cm_defs.h"
#include "cs_pipe.h"
#include "cm_spinlock.h"
#include "cm_queue.h"
#include "cm_sync.h"
#include "executor.h"
#include "dcc_interface.h"
#include "cm_profile_stat.h"

#ifdef __cplusplus
extern "C" {
#endif

#define SRV_SESS_API_REQ_BUFF_LEN (MAX_KV_KEY_LEN + MAX_KV_VALUE_LEN * 2 + 2 * sizeof(uint32) + 64)
#define DCC_MAX_SESS_APPLY_INST_NUM 40

typedef enum en_session_type {
    SESSION_TYPE_CS = 1,
    SESSION_TYPE_API,
} session_type_e;

typedef struct st_sess_watch_record {
    text_t key;
    bool32 is_prefix;
    uint32 session_id;
    struct st_sess_watch_record *prev;
    struct st_sess_watch_record *next;
} sess_watch_record_t;

typedef struct st_session {
    uint32 id;
    uint32 serial_number; // cs msg SN
    void *stg_handle;  // handle of storage
    session_type_e ses_type;
    uint32 proto_type;
    cs_pipe_t pipe_entity;  // if pipe info specified when create a session, pointer pipe will point to
    // if pipe info specified when create a session, it will point to pipe_entity, otherwise null assigned
    cs_pipe_t *pipe;
    char os_host[CM_HOST_NAME_BUFFER_SIZE];
    union {
        cs_packet_t *recv_pack;
        char *req_buf; // for api req buf
    };
    cs_packet_t *send_pack;
    struct st_agent *agent;
    struct st_reactor *reactor;
    struct st_session *prev;
    struct st_session *next;
    spinlock_t detaching_lock;
    struct {
        bool32 is_reg : 1;
        bool32 is_free : 1;
        bool32 unused : 30;
    };
    uint64 index;
    cm_event_t event;
    int64 start_proc_time;
    uint64 write_key;
    uint32 serial_id; // attach session cnt
    uint32 qry_eof;
    sess_watch_record_t *watch_head;
} session_t;

typedef struct st_session_pool {
    spinlock_t lock;
    biqueue_t idle_sessions;
    uint32 hwm; /* high water mark */
    uint32 max_sessions;
    session_t *sessions[CM_MAX_SESSIONS];
} session_pool_t;

typedef struct st_sess_apply_inst {
    uint32 id;
    spinlock_t lock;
    biqueue_t apply_que;
    thread_t thread;
    cs_packet_t pack;
    cm_event_t event;
} sess_apply_inst_t;

typedef struct st_sess_apply_mgr {
    uint32 apply_inst_num;
    bool32 is_ready;
    sess_apply_inst_t *appy_inst[DCC_MAX_SESS_APPLY_INST_NUM];
    uint32 node_id;
} sess_apply_mgr_t;

typedef struct st_sess_consense_obj {
    uint32 nodeid;
    uint32 sid;
    uint32 serial_id;
    uint32 cmd;
    bool32 cmd_result;
    uint64 index;
    int32 sequence;
    struct st_sess_consense_obj *prev;
    struct st_sess_consense_obj *next;
} sess_consense_obj_t;

status_t srv_alloc_session(session_t **session, const cs_pipe_t *pipe, session_type_e type);
status_t srv_create_session(const cs_pipe_t *pipe);
void srv_release_session(session_t *session);
void srv_deinit_session(session_t *session);
void srv_return_session(session_t *session);
status_t srv_init_session_pool(void);
void srv_kill_all_session(void);
void srv_wait_all_session_free(void);
status_t srv_process_command(session_t *session);

status_t srv_get_sess_by_id(uint32 sessid, session_t **session);
status_t srv_sess_consensus_proc(const exc_consense_obj_t* obj);
status_t srv_init_sess_apply_mgr(void);
void srv_uninit_sess_apply_mgr(void);

#ifdef __cplusplus
}
#endif
#endif /* __SRV_SESSION_H__ */