/*****************************************************************************
 * eit.h: ETSI EN 300 468 Event Information Table (EIT)
 *****************************************************************************
 * Copyright (C) 2009-2010 VideoLAN
 *
 * Authors: Christophe Massiot <massiot@via.ecp.fr>
 *
 * Permission is hereby granted, free of charge, to any person obtaining
 * a copy of this software and associated documentation files (the
 * "Software"), to deal in the Software without restriction, including
 * without limitation the rights to use, copy, modify, merge, publish,
 * distribute, sublicense, and/or sell copies of the Software, and to
 * permit persons to whom the Software is furnished to do so, subject
 * to the following conditions:
 *
 * The above copyright notice and this permission notice shall be
 * included in all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
 * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
 * IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
 *****************************************************************************/

/*
 * Normative references:
 *  - ETSI EN 300 468 V1.11.1 (2010-04) (SI in DVB systems)
 */

#ifndef __BITSTREAM_DVB_EIT_H__
#define __BITSTREAM_DVB_EIT_H__

#include <bitstream/common.h>
#include <bitstream/mpeg/psi/psi.h>
#include <bitstream/mpeg/psi/descriptors.h>

#ifdef __cplusplus
extern "C"
{
#endif

/*****************************************************************************
 * Event Information Table
 *****************************************************************************/
#define EIT_PID                         0x12
#define EIT_TABLE_ID_PF_ACTUAL          0x4e
#define EIT_TABLE_ID_PF_OTHER           0x4f
#define EIT_TABLE_ID_SCHED_ACTUAL_FIRST 0x50
#define EIT_TABLE_ID_SCHED_ACTUAL_LAST  0x5f
#define EIT_TABLE_ID_SCHED_OTHER_FIRST  0x60
#define EIT_TABLE_ID_SCHED_OTHER_LAST   0x6f
#define EIT_HEADER_SIZE                 (PSI_HEADER_SIZE_SYNTAX1 + 6)
#define EIT_EVENT_SIZE                  12

#define eit_set_sid psi_set_tableidext
#define eit_get_sid psi_get_tableidext

static inline void eit_init(uint8_t *p_eit, bool b_actual)
{
    psi_init(p_eit, true);
    psi_set_tableid(p_eit, b_actual ? EIT_TABLE_ID_PF_ACTUAL :
                    EIT_TABLE_ID_PF_OTHER);
}

static inline void eit_set_length(uint8_t *p_eit, uint16_t i_eit_length)
{
    psi_set_length(p_eit, EIT_HEADER_SIZE + PSI_CRC_SIZE - PSI_HEADER_SIZE
                    + i_eit_length);
}

static inline void eit_set_tsid(uint8_t *p_eit, uint16_t i_tsid)
{
    p_eit[8] = i_tsid >> 8;
    p_eit[9] = i_tsid & 0xff;
}

static inline uint16_t eit_get_tsid(const uint8_t *p_eit)
{
    return (p_eit[8] << 8) | p_eit[9];
}

static inline uint16_t eitn_get_desclength(const uint8_t *p_eit_n)
{
    return ((p_eit_n[10] & 0xf) << 8) | p_eit_n[11];
}

static inline bool eit_validate_event(const uint8_t *p_eit,
                                      const uint8_t *p_eit_n,
                                      uint16_t i_desclength)
{
    uint16_t i_section_size = psi_get_length(p_eit) + PSI_HEADER_SIZE
                               - PSI_CRC_SIZE;
    return (p_eit_n + EIT_EVENT_SIZE + i_desclength
             <= p_eit + i_section_size);
}

static inline bool eit_validate(const uint8_t *p_eit)
{
    uint16_t i_section_size = psi_get_length(p_eit) + PSI_HEADER_SIZE
                               - PSI_CRC_SIZE;
    uint8_t i_tid = psi_get_tableid(p_eit);
    const uint8_t *p_eit_n;

    if (!psi_get_syntax(p_eit)
         || (i_tid != EIT_TABLE_ID_PF_ACTUAL
              && i_tid != EIT_TABLE_ID_PF_OTHER
              && !(i_tid >= EIT_TABLE_ID_SCHED_ACTUAL_FIRST
                    && i_tid <= EIT_TABLE_ID_SCHED_ACTUAL_LAST)
              && !(i_tid >= EIT_TABLE_ID_SCHED_OTHER_FIRST
                    && i_tid <= EIT_TABLE_ID_SCHED_OTHER_LAST)))
        return false;

    if (!psi_check_crc(p_eit))
        return false;

    p_eit_n = p_eit + EIT_HEADER_SIZE;

    while (p_eit_n + EIT_EVENT_SIZE - p_eit <= i_section_size
            && p_eit_n + EIT_EVENT_SIZE + eitn_get_desclength(p_eit_n) - p_eit
                <= i_section_size) {
        if (!descs_validate(p_eit_n + 10))
            return false;

        p_eit_n += EIT_EVENT_SIZE + eitn_get_desclength(p_eit_n);
    }

    return (p_eit_n - p_eit == i_section_size);
}

/* TODO: unfinished support */

#ifdef __cplusplus
}
#endif

#endif