/*
 * Copyright (c) 2013 - Andre Roth <neolynx@gmail.com>
 *
 * 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 version 2.1 of the License.
 *
 * 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 program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
 * Or, point your browser to http://www.gnu.org/licenses/old-licenses/gpl-2.0.html
 *
 */

/**
 * @file mgt.h
 * @ingroup dvb_table
 * @brief Provides the table parser for the ATSC MGT (Master Guide Table)
 * @copyright GNU Lesser General Public License version 2.1 (LGPLv2.1)
 * @author Andre Roth
 *
 * @par Relevant specs
 * The table described herein is defined at:
 * - ATSC A/65:2009
 *
 * @see
 * http://www.etherguidesystems.com/help/sdos/atsc/syntax/tablesections/MGT.aspx
 *
 * @par Bug Report
 * Please submit bug reports and patches to linux-media@vger.kernel.org
 */

module libdvbv5_d.mgt;

import core.sys.posix.unistd;

import libdvbv5_d.descriptors: dvb_desc;
import libdvbv5_d.dvb_fe: dvb_v5_fe_parms;
import libdvbv5_d.header: dvb_table_header;

extern (C):

/* ssize_t */

/**
 * @def ATSC_TABLE_MGT
 *	@brief ATSC MGT table ID
 *	@ingroup dvb_table
 */
enum ATSC_TABLE_MGT = 0xC7;

/**
 * @struct atsc_table_mgt_table
 * @brief ATSC tables descrition at MGT table
 * @ingroup dvb_table
 *
 * @param type		table type
 * @param pid		table type pid
 * @param type_version	type type version number
 * @param size		number of bytes for the table entry
 * @param desc_length	table type descriptors length
 * @param descriptor	pointer to struct dvb_desc
 * @param next		pointer to struct atsc_table_mgt_table
 *
 * This structure is used to store the original VCT channel table,
 * converting the integer fields to the CPU endianness.
 *
 * The undocumented parameters are used only internally by the API and/or
 * are fields that are reserved. They shouldn't be used, as they may change
 * on future API releases.
 *
 * Everything after atsc_table_mgt_table::descriptor (including it) won't
 * be bit-mapped * to the data parsed from the MPEG TS. So, metadata are
 * added there.
 */
struct atsc_table_mgt_table
{
    import std.bitmanip : bitfields;
    align (1):

    ushort type;

    union
    {
        align (1):

        ushort bitfield;

        struct
        {
            import std.bitmanip : bitfields;
            align (1):

            mixin(bitfields!(
                ushort, "pid", 13,
                ushort, "one", 3));
        }
    }

    mixin(bitfields!(
        ubyte, "type_version", 5,
        ubyte, "one2", 3));

    uint size;

    union
    {
        align (1):

        ushort bitfield2;

        struct
        {
            import std.bitmanip : bitfields;
            align (1):

            mixin(bitfields!(
                ushort, "desc_length", 12,
                ushort, "one3", 4));
        }
    }

    // struct dvb_desc;
    dvb_desc* descriptor;
    atsc_table_mgt_table* next;
}

/**
 * @struct atsc_table_mgt
 * @brief ATSC MGT table
 * @ingroup dvb_table
 *
 * @param header		struct dvb_table_header content
 * @param protocol_version	protocol version
 * @param tables		tables_defined Number of tables defined
 * @param table			pointer to struct atsc_table_mgt_table
 * @param descriptor		pointer to struct dvb_desc
 *
 * This structure is used to store the original MGT channel table,
 * converting the integer fields to the CPU endianness.
 *
 * The undocumented parameters are used only internally by the API and/or
 * are fields that are reserved. They shouldn't be used, as they may change
 * on future API releases.
 *
 * Everything after atsc_table_mgt::table (including it) won't
 * be bit-mapped * to the data parsed from the MPEG TS. So, metadata are
 * added there.
 */
struct atsc_table_mgt
{
    align (1):

    dvb_table_header header;
    ubyte protocol_version;
    ushort tables;
    atsc_table_mgt_table* table;
    dvb_desc* descriptor;
}

/**
 * @brief Macro used to find a table inside a MGT table
 *
 * @param _table	channel to seek
 * @param _mgt		pointer to struct atsc_table_mgt_table
 */

// struct dvb_v5_fe_parms;

/**
 * @brief Initializes and parses MGT table
 * @ingroup dvb_table
 *
 * @param parms	struct dvb_v5_fe_parms pointer to the opened device
 * @param buf buffer containing the MGT raw data
 * @param buflen length of the buffer
 * @param table pointer to struct atsc_table_mgt to be allocated and filled
 *
 * This function allocates an ATSC MGT table and fills the fields inside
 * the struct. It also makes sure that all fields will follow the CPU
 * endianness. Due to that, the content of the buffer may change.
 *
 * @return On success, it returns the size of the allocated struct.
 *	   A negative value indicates an error.
 */
ssize_t atsc_table_mgt_init (
    dvb_v5_fe_parms* parms,
    const(ubyte)* buf,
    ssize_t buflen,
    atsc_table_mgt** table);

/**
 * @brief Frees all data allocated by the MGT table parser
 * @ingroup dvb_table
 *
 * @param table pointer to struct atsc_table_mgt to be freed
 */
void atsc_table_mgt_free (atsc_table_mgt* table);

/**
 * @brief Prints the content of the MGT table
 * @ingroup dvb_table
 *
 * @param parms	struct dvb_v5_fe_parms pointer to the opened device
 * @param table pointer to struct atsc_table_mgt
 */
void atsc_table_mgt_print (dvb_v5_fe_parms* parms, atsc_table_mgt* table);