/*!
 * restd.h
 *
 * Copyright (c) 2015-2020, NADAL Jean-Baptiste. All rights reserved.
 *
 * This library is free software; you can redistribute it and/or
 * modify it under the terms of the GNU Lesser General Public
 * License as published by the Free Software Foundation; either
 * version 2.1 of the License, or (at your option) any later version.
 *
 * This library is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
 * Lesser General Public License for more details.
 *
 * You should have received a copy of the GNU Lesser General Public
 * License along with this library; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
 * MA 02110-1301 USA
 * 
 * @Author:  NADAL Jean-Baptiste
 * @Date: 07/02/2020
 *
 */

#ifndef _RESTD_H
#define _RESTD_H

/*------------------------------- INCLUDES ----------------------------------*/

#include <pthread.h>

#include <event2/http.h>

#include <qlibc/qlibc.h>

/*------------------------------- TYPEDEFS ----------------------------------*/

typedef struct restd_server_s restd_server_t;
typedef struct restd_hook_s restd_hook_t;
typedef struct restd_resp_s restd_resp_t;

typedef int (*restd_callback)(restd_resp_t *response, void *arg);
typedef int (*restd__error_callback)(restd_resp_t *response, int reason, void *arg);

/*------------------------------- INCLUDES ----------------------------------*/

extern restd_server_t *restd_server_new(void);
extern void restd_server_free(restd_server_t *server);
extern int restd_server_start(restd_server_t *server);
extern int restd_server_attach_event_loop(restd_server_t *server, struct event_base *ev_base);

extern void restd_server_set_option(restd_server_t *server, const char *key, const char *value);

extern void restd_server_register_hook_on_path(restd_server_t *server, enum evhttp_cmd_type method, const char *path,
                                               restd_callback cb, void *userdata);

extern void restd_server_register_error_handler(restd_server_t *server, restd__error_callback cb, void *userdata);

extern void restd_http_response(restd_resp_t *response, int code, const char *contenttype, const char *data);
extern char *restd_http_get_body(restd_resp_t *response);

extern restd_hook_t *restd_hook_new(void);
extern void restd_hook_free(restd_hook_t *hook);

extern restd_resp_t *restd_resp_new(void);
extern void restd_resp_free(restd_resp_t *response);


/*------------------------------- DEFINES ------------------------------------*/

/*
 * These flags are used for ad_log_level();
 */
enum restd_log_e
{
    RESTD_LOG_DISABLE = 0,
    RESTD_LOG_ERROR,
    RESTD_LOG_WARN,
    RESTD_LOG_INFO,
    RESTD_LOG_DEBUG,
    RESTD_LOG_DEBUG2,
};

#define RESTD_OK (0)       /*!< I'm done with this request. Escalate to other hooks. */
#define RESTD_FAILED (1)       /*!< I'm done with this request. But the Process failed. */

#define RESTD_ERROR_METHOD_NOT_ALLOWED (2)
#define RESTD_ERROR_PATH_NOT_FOUND (3)

/*---------------------------------------------------------------------------*\
|                            DATA STRUCTURES                                  |
\*---------------------------------------------------------------------------*/

/**
 * Server info container.
 */
struct restd_server_s
{
    int errcode;       /*!< exit status. 0 for normal exit, non zero for error. */
    pthread_t *thread; /*!< thread object. not null if server runs as a thread */

    qhashtbl_t *options;             /*!< server options */
    qlist_t *hooks;                  /*!< list of registered hooks */
    struct event_base *evbase;       /*!< event base */
    struct evhttp *evhttp;

    struct bufferevent *notify_buffer; /*!< internal notification channel */

    restd__error_callback error_handler;
    void *error_userdata;
};

/*
 * User callback hook container.
 */
struct restd_hook_s
{
    enum evhttp_cmd_type method;
    char *path;
    restd_callback cb;
    void *userdata;
    qlist_t *path_fragments;
    bool has_parameter;
    int parameter_position;
    char *parameter_name;
    char *action_name;
};

/*
 * Response callback parameter.
 */
struct restd_resp_s
{
    struct evhttp_request *request;
    bool has_parameter;
    char *parameter_name;
    uint32_t parameter_value;
    char *action;
};

#endif /*_RESTD_H */