/*
 *  Copyright (C) 2004-2008 Christos Tsantilas
 *
 *  This program 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 program 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.
 */

/**
 \defgroup ICAPCLIENT ICAP client request API
 \ingroup API
 * API for implementing ICAP clients
 */

#ifndef _REQUEST_H
#define _REQUEST_H

#include "header.h"
#include "service.h"
#include "net_io.h"
#include "array.h"

#ifdef __cplusplus
extern "C"
{
#endif

/**
 \defgroup REQUEST ICAP request API
 \ingroup API
 * ICAP request related API.
 */

/**
 \defgroup ICAPCLIENT ICAP client request API
 \ingroup API
 * API for implementing ICAP clients
 */

//enum REQUEST_STATUS { WAIT,SERVED };

enum GETDATA_STATUS {GET_NOTHING = 0,GET_HEADERS,GET_PREVIEW,GET_BODY,GET_EOF};
enum SENDDATA_STATUS {SEND_NOTHING = 0, SEND_RESPHEAD, SEND_HEAD1, SEND_HEAD2, SEND_HEAD3, SEND_BODY, SEND_EOF };

/*enum BODY_RESPONCE_STATUS{ CHUNK_DEF = 1,CHUNK_BODY,CHUNK_END};*/

enum CLIENT_STATUS {
    CLIENT_INIT = 0,
    CLIENT_SEND_HEADERS,
    CLIENT_SEND_HEADERS_WRITE_NOTHING = CLIENT_SEND_HEADERS,
    CLIENT_SEND_HEADERS_WRITE_ICAP_HEADERS,
    CLIENT_SEND_HEADERS_WRITE_REQ_HEADERS,
    CLIENT_SEND_HEADERS_WRITE_RES_HEADERS,
    CLIENT_SEND_HEADERS_WRITE_PREVIEW_INFO,
    CLIENT_SEND_HEADERS_WRITE_PREVIEW,
    CLIENT_SEND_HEADERS_WRITE_EOF_INFO,
    CLIENT_SEND_HEADERS_FINISHED,

    CLIENT_READ_PREVIEW_RESPONSE,

    CLIENT_PROCESS_DATA,
    CLIENT_PROCESS_DATA_GET_NOTHING = CLIENT_PROCESS_DATA,
    CLIENT_PROCESS_DATA_GET_HEADERS,
    CLIENT_PROCESS_DATA_HEADERS_FINISHED,
    CLIENT_PROCESS_DATA_GET_BODY,
    CLIENT_PROCESS_DATA_GET_EOF
};

#define NEEDS_TO_READ_FROM_ICAP  0x1
#define NEEDS_TO_WRITE_TO_ICAP   0x2
#define NEEDS_TO_READ_USER_DATA  0x4
#define NEEDS_TO_WRITE_USER_DATA 0x8


#define CI_NO_STATUS   0
#define CI_OK                1
#define CI_NEEDS_MORE 2
#define CI_ERROR          -1
#define CI_EOF              -2


#define EXTRA_CHUNK_SIZE  30
#define MAX_CHUNK_SIZE    4064   /*4096 -EXTRA_CHUNK_SIZE-2*/
#define MAX_USERNAME_LEN 255

typedef struct ci_buf {
    char *buf;
    int size;
    int used;
} ci_buf_t;


struct ci_service_module;
struct ci_ring_buf;

/**
   \typedef ci_request_t
   \ingroup REQUEST
   * This is the struct which holds all the data which represent an ICAP
   * request. The developers should not access directly the fields of
   * this struct but better use the documented macros and functions
*/
typedef struct ci_request {
    ci_connection_t *connection;
    int packed;
    int type;
    char req_server[CI_MAXHOSTNAMELEN+1];
    int access_type;
    char user[MAX_USERNAME_LEN+1];
    char service[MAX_SERVICE_NAME+1];
    char args[MAX_SERVICE_ARGS];
    int preview;
    int keepalive;
    int allow204;
    int hasbody;
    int responce_hasbody;
    struct ci_buf preview_data;
    struct ci_service_module *current_service_mod;
    ci_headers_list_t *request_header;
    ci_headers_list_t *response_header;
    ci_encaps_entity_t *entities[5];//At most 3 and 1 for termination.....
    ci_encaps_entity_t *trash_entities[7];
    ci_headers_list_t *xheaders;

    void *service_data;

    char rbuf[BUFSIZE];
    char wbuf[MAX_CHUNK_SIZE+EXTRA_CHUNK_SIZE+2];
    int eof_received;
    int eof_sent;
    int data_locked;

    char *pstrblock_read;
    int  pstrblock_read_len;
    unsigned int current_chunk_len;
    unsigned int chunk_bytes_read;
    unsigned int write_to_module_pending;

    int status;
    int return_code;
    char *pstrblock_responce;
    int remain_send_block_bytes;

    /*Used to echo data back to a client which does not support preview
      in the case of 204 outside preview.*/
    struct ci_ring_buf *echo_body;

    /*Caching values for various subsystems*/
    int preview_data_type;
    int auth_required;

    /*log string*/
    char *log_str;
    ci_str_array_t *attributes;

    /* statistics */
    uint64_t bytes_in; /*May include bytes from next pipelined request*/
    uint64_t bytes_out;
    uint64_t request_bytes_in; /*Current request input bytes*/
    uint64_t http_bytes_in;
    uint64_t http_bytes_out;
    uint64_t body_bytes_in;
    uint64_t body_bytes_out;

    /* added flags/variables*/
    int allow206;
    int64_t i206_use_original_body;
    ci_ip_t xclient_ip;
} ci_request_t;

#define lock_data(req) (req->data_locked = 1)
#define unlock_data(req) (req->data_locked = 0)

/*This functions needed in server (mpmt_server.c ) */
ci_request_t *newrequest(ci_connection_t *connection);
int recycle_request(ci_request_t *req,ci_connection_t *connection);
int keepalive_request(ci_request_t *req);
int process_request(ci_request_t *);

/*Functions used in both server and icap-client library*/
CI_DECLARE_FUNC(int) parse_chunk_data(ci_request_t *req, char **wdata);
CI_DECLARE_FUNC(int) net_data_read(ci_request_t *req);
CI_DECLARE_FUNC(int) process_encapsulated(ci_request_t *req, const char *buf);

/*********************************************/
/*Buffer functions (I do not know if they must included in ci library....) */
CI_DECLARE_FUNC(void)  ci_buf_init(struct ci_buf *buf);
CI_DECLARE_FUNC(void)  ci_buf_reset(struct ci_buf *buf);
CI_DECLARE_FUNC(int)   ci_buf_mem_alloc(struct ci_buf *buf,int size);
CI_DECLARE_FUNC(void)  ci_buf_mem_free(struct ci_buf *buf);
CI_DECLARE_FUNC(int)   ci_buf_write(struct ci_buf *buf,char *data,int len);
CI_DECLARE_FUNC(int)   ci_buf_reset_size(struct ci_buf *buf,int req_size);

/***************/
/*API defines */
#define ci_service_data(req) ((req)->service_data)
#define ci_allow204(req)     ((req)->allow204)
#define ci_allow206(req)     ((req)->allow206)
/*API functions ......*/
CI_DECLARE_FUNC(ci_request_t *)  ci_request_alloc(ci_connection_t *connection);
CI_DECLARE_FUNC(void)         ci_request_reset(ci_request_t *req);
CI_DECLARE_FUNC(void)         ci_request_destroy(ci_request_t *req);
CI_DECLARE_FUNC(void)         ci_request_pack(ci_request_t *req);
CI_DECLARE_FUNC(void)         ci_response_pack(ci_request_t *req);
CI_DECLARE_FUNC(ci_encaps_entity_t *) ci_request_alloc_entity(ci_request_t *req,int type,int val);
CI_DECLARE_FUNC(int)          ci_request_release_entity(ci_request_t *req,int pos);
CI_DECLARE_FUNC(char *)       ci_request_set_log_str(ci_request_t *req, char *logstr);
CI_DECLARE_FUNC(int)       ci_request_set_str_attribute(ci_request_t *req, const char *name, const char *value);

CI_DECLARE_FUNC(int)          ci_request_206_origin_body(ci_request_t *req, uint64_t offset);

/*ICAP client api*/
CI_DECLARE_FUNC(ci_request_t *)  ci_client_request(ci_connection_t *conn,const char *server,const char *service);
CI_DECLARE_FUNC(void)         ci_client_request_reuse(ci_request_t *req);

CI_DECLARE_FUNC(int)          ci_client_get_server_options(ci_request_t *req,int timeout);
CI_DECLARE_FUNC(int)          ci_client_get_server_options_non_blocking(ci_request_t *req);

CI_DECLARE_FUNC(int)          ci_client_icapfilter(ci_request_t *req,
        int timeout,
        ci_headers_list_t *req_headers,
        ci_headers_list_t *resp_headers,
        void *data_source,
        int (*source_read)(void *,char *,int),
        void *data_dest,
        int (*dest_write) (void *,char *,int));

/**
 \ingroup ICAPCLIENT
 * Function to send HTTP objects to an ICAP server for processing. It sends
 * the HTTP request headers, and the HTTP response from HTTP server (headers
 * plus body data), and receives modified HTTP response headers and body data.
 \param req The ci_request_t object.
 \param io_action is a combination set of ci_wait_for_read and
 *      ci_wait_for_write flags. It has the meaning that the
 *      ci_client_icapfilter_nonblocking can read from or write to ICAP server.
 \param req_headers The HTTP request headers to use.
 \param resp_headers The HTTP response headers to use.
 \param data_source User data to use with source_read callback function.
 \param source_read Callback function to use for reading HTTP object body data.
 \param data_dest User data to use with dest_write callback function.
 \param dest_write Callback function to use for storing modified body data.
 \return combination of the following flags: NEEDS_TO_READ_FROM_ICAP,
 *       NEEDS_TO_WRITE_TO_ICAP, NEEDS_TO_READ_USER_DATA and
 *       NEEDS_TO_WRITE_USER_DATA.
 */
CI_DECLARE_FUNC(int) ci_client_icapfilter_nonblocking(ci_request_t * req, int io_action,
        ci_headers_list_t * req_headers,
        ci_headers_list_t * resp_headers,
        void *data_source,
        int (*source_read) (void *, char *, int),
        void *data_dest,
        int (*dest_write) (void *, char *, int));

CI_DECLARE_FUNC(int) ci_client_http_headers_completed(ci_request_t * req);

CI_DECLARE_FUNC(void) ci_client_set_user_agent(const char *agent);

CI_DECLARE_FUNC(void) ci_client_library_init();

CI_DECLARE_FUNC(void) ci_client_library_release();

/** Deprecated. Use ci_connect_to declared in net_io.h instead. */
CI_DECLARE_FUNC(ci_connection_t *)  ci_client_connect_to(char *servername,int port,int proto);

#ifdef __CI_COMPAT
#define request_t   ci_request_t
#endif

#ifdef __cplusplus
}
#endif

#endif