/* cropscale.c

   Copyright (c) 2003-2012 HandBrake Team
   This file is part of the HandBrake source code
   Homepage: <http://handbrake.fr/>.
   It may be used under the terms of the GNU General Public License v2.
   For full terms see the file COPYING file or visit http://www.gnu.org/licenses/gpl-2.0.html
 */
   
#include "hb.h"
#include "hbffmpeg.h"

struct hb_filter_private_s
{
    int                 width_in;
    int                 height_in;
    int                 pix_fmt;
    int                 pix_fmt_out;
    int                 width_out;
    int                 height_out;
    int                 crop[4];
    struct SwsContext * context;
};

static int hb_crop_scale_init( hb_filter_object_t * filter,
                               hb_filter_init_t * init );

static int hb_crop_scale_work( hb_filter_object_t * filter,
                               hb_buffer_t ** buf_in,
                               hb_buffer_t ** buf_out );

static int hb_crop_scale_info( hb_filter_object_t * filter,
                               hb_filter_info_t * info );

static void hb_crop_scale_close( hb_filter_object_t * filter );

hb_filter_object_t hb_filter_crop_scale =
{
    .id            = HB_FILTER_CROP_SCALE,
    .enforce_order = 1,
    .name          = "Crop and Scale",
    .settings      = NULL,
    .init          = hb_crop_scale_init,
    .work          = hb_crop_scale_work,
    .close         = hb_crop_scale_close,
    .info          = hb_crop_scale_info,
};

static int hb_crop_scale_init( hb_filter_object_t * filter,
                               hb_filter_init_t * init )
{
    filter->private_data = calloc( 1, sizeof(struct hb_filter_private_s) );
    hb_filter_private_t * pv = filter->private_data;

    // TODO: add pix format option to settings
    pv->pix_fmt_out = init->pix_fmt;
    pv->width_in = init->width;
    pv->height_in = init->height;
    pv->width_out = init->width;
    pv->height_out = init->height;
    memcpy( pv->crop, init->crop, sizeof( int[4] ) );
    if( filter->settings )
    {
        sscanf( filter->settings, "%d:%d:%d:%d:%d:%d",
                &pv->width_out, &pv->height_out,
                &pv->crop[0], &pv->crop[1], &pv->crop[2], &pv->crop[3] );
    }
    // Set init values so the next stage in the pipline
    // knows what it will be getting
    init->pix_fmt = pv->pix_fmt;
    init->width = pv->width_out;
    init->height = pv->height_out;
    memcpy( init->crop, pv->crop, sizeof( int[4] ) );

    return 0;
}

static int hb_crop_scale_info( hb_filter_object_t * filter,
                               hb_filter_info_t * info )
{
    hb_filter_private_t * pv = filter->private_data;

    if( !pv )
        return 0;

    // Set init values so the next stage in the pipline
    // knows what it will be getting
    memset( info, 0, sizeof( hb_filter_info_t ) );
    info->out.pix_fmt = pv->pix_fmt;
    info->out.width = pv->width_out;
    info->out.height = pv->height_out;
    memcpy( info->out.crop, pv->crop, sizeof( int[4] ) );

    int cropped_width = pv->width_in - ( pv->crop[2] + pv->crop[3] );
    int cropped_height = pv->height_in - ( pv->crop[0] + pv->crop[1] );

    sprintf( info->human_readable_desc, 
        "source: %d * %d, crop (%d/%d/%d/%d): %d * %d, scale: %d * %d",
        pv->width_in, pv->height_in,
        pv->crop[0], pv->crop[1], pv->crop[2], pv->crop[3],
        cropped_width, cropped_height, pv->width_out, pv->height_out );

    return 0;
}

static void hb_crop_scale_close( hb_filter_object_t * filter )
{
    hb_filter_private_t * pv = filter->private_data;

    if ( !pv )
    {
        return;
    }

    if ( pv->context )
    {
        sws_freeContext( pv->context );
    }

    free( pv );
    filter->private_data = NULL;
}

static hb_buffer_t* crop_scale( hb_filter_private_t * pv, hb_buffer_t * in )
{
    AVPicture           pic_in;
    AVPicture           pic_out;
    AVPicture           pic_crop;
    hb_buffer_t * out;
    out = hb_video_buffer_init( pv->width_out, pv->height_out );

    hb_avpicture_fill( &pic_in, in );
    hb_avpicture_fill( &pic_out, out );

    // Crop; this alters the pointer to the data to point to the
    // correct place for cropped frame
    av_picture_crop( &pic_crop, &pic_in, in->f.fmt,
                     pv->crop[0], pv->crop[2] );

    if ( !pv->context ||
         pv->width_in   != in->f.width  ||
         pv->height_in  != in->f.height ||
         pv->pix_fmt != in->f.fmt )
    {
        // Something changed, need a new scaling context.
        if( pv->context )
            sws_freeContext( pv->context );

        pv->context = hb_sws_get_context(
                                in->f.width  - (pv->crop[2] + pv->crop[3]),
                                in->f.height - (pv->crop[0] + pv->crop[1]),
                                in->f.fmt,
                                out->f.width, out->f.height, out->f.fmt,
                                SWS_LANCZOS | SWS_ACCURATE_RND );
        pv->width_in = in->f.width;
        pv->height_in = in->f.height;
        pv->pix_fmt = in->f.fmt;
    }

    // Scale pic_crop into pic_render according to the
    // context set up above
    sws_scale(pv->context,
              (const uint8_t* const*)pic_crop.data,
              pic_crop.linesize,
              0, in->f.height - (pv->crop[0] + pv->crop[1]),
              pic_out.data,  pic_out.linesize);

    out->s = in->s;
    hb_buffer_move_subs( out, in );
    return out;
}

static int hb_crop_scale_work( hb_filter_object_t * filter,
                               hb_buffer_t ** buf_in,
                               hb_buffer_t ** buf_out )
{
    hb_filter_private_t * pv = filter->private_data;
    hb_buffer_t * in = *buf_in;

    if ( in->size <= 0 )
    {
        *buf_out = in;
        *buf_in = NULL;
        return HB_FILTER_DONE;
    }

    if ( !pv )
    {
        *buf_out = in;
        *buf_in = NULL;
        return HB_FILTER_OK;
    }

    // If width or height were not set, set them now based on the
    // input width & height
    if ( pv->width_out <= 0 || pv->height_out <= 0 )
    {
        pv->width_out = in->f.width - (pv->crop[2] + pv->crop[3]);
        pv->height_out = in->f.height - (pv->crop[0] + pv->crop[1]);
    }
    if ( in->f.fmt == pv->pix_fmt_out &&
         !pv->crop[0] && !pv->crop[1] && !pv->crop[2] && !pv->crop[3] &&
         in->f.width == pv->width_out && in->f.height == pv->height_out )
    {
        *buf_out = in;
        *buf_in = NULL;
        return HB_FILTER_OK;
    }
    *buf_out = crop_scale( pv, in );

    return HB_FILTER_OK;
}