#ifndef WH_AVUTIL_TIMECODE_H_a2fa267b_
#define WH_AVUTIL_TIMECODE_H_a2fa267b_

/*
 * This file was stolen from ffmpeg and modified for usability here.
 *  The original is
 * 
 * Copyright (c) 2006 Smartjog S.A.S, Baptiste Coudurier <baptiste.coudurier@gmail.com>
 * Copyright (c) 2011-2012 Smartjog S.A.S, Clément Bœsch <clement.boesch@smartjog.com>
 *
 * This version is a derivative work of that version.  It is not free
 *  software; it is licensed under the GNU Lesser General Public
 *  License version 2.1, which places nontrivial restrictions on what
 *  may be done with it.  (I'm not terribly happy about that, but for
 *  my purposes accepting LGPL-infected code is a lower price than
 *  reimplementing it all myself.)
 *
 * The LGPL v2.1 as distributed with ffmpeg is in the accompanying file
 *  `LGPL-v2.1'.
 */

#define AV_TIMECODE_STR_SIZE 16

#define AV_TIMECODE_OPTION(ctx, string_field, flags)                     \
    "timecode", "set timecode value following hh:mm:ss[:;.]ff format, "  \
                "use ';' or '.' before frame number for drop frame",     \
    offsetof(ctx, string_field),                                         \
    AV_OPT_TYPE_STRING, {.str=NULL}, CHAR_MIN, CHAR_MAX, flags

enum AVTimecodeFlag {
    AV_TIMECODE_FLAG_DROPFRAME      = 1<<0, ///< timecode is drop frame
    AV_TIMECODE_FLAG_24HOURSMAX     = 1<<1, ///< timecode wraps after 24 hours
    AV_TIMECODE_FLAG_ALLOWNEGATIVE  = 1<<2, ///< negative time values are allowed
};

typedef struct {
    int start;          ///< timecode frame start (first base frame number)
    uint32_t flags;     ///< flags such as drop frame, +24 hours support, ...
    AVRational rate;    ///< frame rate in rational form
    unsigned fps;       ///< frame per second; must be consistent with the rate field
} AVTimecode;

/**
 * Adjust frame number for NTSC drop frame time code.
 *
 * @param framenum frame number to adjust
 * @return         adjusted frame number
 * @warning        adjustment is only valid in NTSC 29.97
 */
int av_timecode_adjust_ntsc_framenum(int framenum);

/**
 * Convert frame number to SMPTE 12M binary representation.
 *
 * @param tc       timecode data correctly initialized
 * @param framenum frame number
 * @return         the SMPTE binary representation
 *
 * @note Frame number adjustment is automatically done in case of drop timecode,
 *       you do NOT have to call av_timecode_adjust_ntsc_framenum().
 * @note The frame number is relative to tc->start.
 * @note Color frame (CF), binary group flags (BGF) and biphase mark polarity
 *       correction (PC) bits are set to zero.
 */
uint32_t av_timecode_get_smpte_from_framenum(const AVTimecode *tc, int framenum);

/**
 * Load timecode string in buf.
 *
 * @param buf      destination buffer, must be at least AV_TIMECODE_STR_SIZE long
 * @param tc       timecode data correctly initialized
 * @param framenum frame number
 * @return         the buf parameter
 *
 * @note Timecode representation can be a negative timecode and have more than
 *       24 hours, but will only be honored if the flags are correctly set.
 * @note The frame number is relative to tc->start.
 */
char *av_timecode_make_string(const AVTimecode *tc, char *buf, int framenum);

/**
 * Get the timecode string from the SMPTE timecode format.
 *
 * @param buf        destination buffer, must be at least AV_TIMECODE_STR_SIZE long
 * @param tcsmpte    the 32-bit SMPTE timecode
 * @param prevent_df prevent the use of a drop flag when it is known the DF bit
 *                   is arbitrary
 * @return           the buf parameter
 */
char *av_timecode_make_smpte_tc_string(char *buf, uint32_t tcsmpte, int prevent_df);

/**
 * Get the timecode string from the 25-bit timecode format (MPEG GOP format).
 *
 * @param buf     destination buffer, must be at least AV_TIMECODE_STR_SIZE long
 * @param tc25bit the 25-bits timecode
 * @return        the buf parameter
 */
char *av_timecode_make_mpeg_tc_string(char *buf, uint32_t tc25bit);

/**
 * Init a timecode struct with the passed parameters.
 *
 * @param log_ctx     a pointer to an arbitrary struct of which the first field
 *                    is a pointer to an AVClass struct (used for av_log)
 * @param tc          pointer to an allocated AVTimecode
 * @param rate        frame rate in rational form
 * @param flags       miscellaneous flags such as drop frame, +24 hours, ...
 *                    (see AVTimecodeFlag)
 * @param frame_start the first frame number
 * @return            0 on success, AVERROR otherwise
 */
int av_timecode_init(AVTimecode *tc, AVRational rate, int flags, int frame_start, void *log_ctx);

/**
 * Parse timecode representation (hh:mm:ss[:;.]ff).
 *
 * @param log_ctx a pointer to an arbitrary struct of which the first field is a
 *                pointer to an AVClass struct (used for av_log).
 * @param tc      pointer to an allocated AVTimecode
 * @param rate    frame rate in rational form
 * @param str     timecode string which will determine the frame start
 * @return        0 on success, AVERROR otherwise
 */
int av_timecode_init_from_string(AVTimecode *tc, AVRational rate, const char *str, void *log_ctx);

#endif