/*
    Copyright (C) 2003 Michael Zucchi <notzed@ximian.com>

    This program is free software; you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation; either version 2 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 General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program; if not, write to the Free Software
    Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
*/

#include <stdio.h>
#include <stdlib.h>
#include <string.h>

#include "config.h"
#include "mp_msg.h"

#include "img_format.h"
#include "mp_image.h"
#include "vf.h"

#include "libvo/fastmemcpy.h"

struct vf_priv_s {
	int mode;
	int frame;
	mp_image_t *dmpi;
};

// Copied verbatim from vf_telecine.c:
static inline void *my_memcpy_pic(void * dst, void * src, int bytesPerLine, int height, int dstStride, int srcStride)
{
	int i;
	void *retval=dst;

	for(i=0; i<height; i++)
	{
		memcpy(dst, src, bytesPerLine);
		src+= srcStride;
		dst+= dstStride;
	}

	return retval;
}

static int put_image(struct vf_instance_s* vf, mp_image_t *mpi, double pts)
{
	int ret = 0;
	mp_image_t *dmpi;

	switch (vf->priv->mode) {
	case 0:
		dmpi = vf->priv->dmpi;
		if (dmpi == NULL) {
			dmpi = vf_get_image(vf->next, mpi->imgfmt,
					    MP_IMGTYPE_STATIC, MP_IMGFLAG_ACCEPT_STRIDE |
					    MP_IMGFLAG_PRESERVE,
					    mpi->width, mpi->height*2);

			vf->priv->dmpi = dmpi;

			memcpy_pic(dmpi->planes[0], mpi->planes[0], mpi->w, mpi->h,
				   dmpi->stride[0]*2, mpi->stride[0]);
			if (mpi->flags & MP_IMGFLAG_PLANAR) {
				memcpy_pic(dmpi->planes[1], mpi->planes[1],
					   mpi->chroma_width, mpi->chroma_height,
					   dmpi->stride[1]*2, mpi->stride[1]);
				memcpy_pic(dmpi->planes[2], mpi->planes[2],
					   mpi->chroma_width, mpi->chroma_height,
					   dmpi->stride[2]*2, mpi->stride[2]);
			}
		} else {
			vf->priv->dmpi = NULL;

			memcpy_pic(dmpi->planes[0]+dmpi->stride[0], mpi->planes[0], mpi->w, mpi->h,
				   dmpi->stride[0]*2, mpi->stride[0]);
			if (mpi->flags & MP_IMGFLAG_PLANAR) {
				memcpy_pic(dmpi->planes[1]+dmpi->stride[1], mpi->planes[1],
					   mpi->chroma_width, mpi->chroma_height,
					   dmpi->stride[1]*2, mpi->stride[1]);
				memcpy_pic(dmpi->planes[2]+dmpi->stride[2], mpi->planes[2],
					   mpi->chroma_width, mpi->chroma_height,
					   dmpi->stride[2]*2, mpi->stride[2]);
			}
			ret = vf_next_put_image(vf, dmpi, MP_NOPTS_VALUE);
		}
		break;
	case 1:
		if (vf->priv->frame & 1)
			ret = vf_next_put_image(vf, mpi, MP_NOPTS_VALUE);
		break;
	case 2:
		if ((vf->priv->frame & 1) == 0)
			ret = vf_next_put_image(vf, mpi, MP_NOPTS_VALUE);
		break;
	case 3:
		dmpi = vf_get_image(vf->next, mpi->imgfmt,
				    MP_IMGTYPE_TEMP, MP_IMGFLAG_ACCEPT_STRIDE,
				    mpi->width, mpi->height*2);
		/* fixme, just clear alternate lines */
		vf_mpi_clear(dmpi, 0, 0, dmpi->w, dmpi->h);
		if ((vf->priv->frame & 1) == 0) {
			memcpy_pic(dmpi->planes[0], mpi->planes[0], mpi->w, mpi->h,
				   dmpi->stride[0]*2, mpi->stride[0]);
			if (mpi->flags & MP_IMGFLAG_PLANAR) {
				memcpy_pic(dmpi->planes[1], mpi->planes[1],
					   mpi->chroma_width, mpi->chroma_height,
					   dmpi->stride[1]*2, mpi->stride[1]);
				memcpy_pic(dmpi->planes[2], mpi->planes[2],
					   mpi->chroma_width, mpi->chroma_height,
					   dmpi->stride[2]*2, mpi->stride[2]);
			}
		} else {
			memcpy_pic(dmpi->planes[0]+dmpi->stride[0], mpi->planes[0], mpi->w, mpi->h,
				   dmpi->stride[0]*2, mpi->stride[0]);
			if (mpi->flags & MP_IMGFLAG_PLANAR) {
				memcpy_pic(dmpi->planes[1]+dmpi->stride[1], mpi->planes[1],
					   mpi->chroma_width, mpi->chroma_height,
					   dmpi->stride[1]*2, mpi->stride[1]);
				memcpy_pic(dmpi->planes[2]+dmpi->stride[2], mpi->planes[2],
					   mpi->chroma_width, mpi->chroma_height,
					   dmpi->stride[2]*2, mpi->stride[2]);
			}
		}
		ret = vf_next_put_image(vf, dmpi, MP_NOPTS_VALUE);
		break;
	case 4:
		// Interleave even lines (only) from Frame 'i' with odd
		// lines (only) from Frame 'i+1', halving the Frame
		// rate and preserving image height.

		dmpi = vf->priv->dmpi;
		
		// @@ Need help:  Should I set dmpi->fields to indicate
		// that the (new) frame will be interlaced!?  E.g. ...
		// dmpi->fields |= MP_IMGFIELD_INTERLACED;
		// dmpi->fields |= MP_IMGFIELD_TOP_FIRST;
		// etc.
		
		if (dmpi == NULL) {
			dmpi = vf_get_image(vf->next, mpi->imgfmt,
					    MP_IMGTYPE_STATIC, MP_IMGFLAG_ACCEPT_STRIDE |
					    MP_IMGFLAG_PRESERVE,
					    mpi->width, mpi->height);

			vf->priv->dmpi = dmpi;

			my_memcpy_pic(dmpi->planes[0], mpi->planes[0], mpi->w, mpi->h/2,
				      dmpi->stride[0]*2, mpi->stride[0]*2);
			if (mpi->flags & MP_IMGFLAG_PLANAR) {
				my_memcpy_pic(dmpi->planes[1], mpi->planes[1],
					      mpi->chroma_width, mpi->chroma_height/2,
					      dmpi->stride[1]*2, mpi->stride[1]*2);
				my_memcpy_pic(dmpi->planes[2], mpi->planes[2],
					      mpi->chroma_width, mpi->chroma_height/2,
					      dmpi->stride[2]*2, mpi->stride[2]*2);
			}
		} else {
			vf->priv->dmpi = NULL;

			my_memcpy_pic(dmpi->planes[0]+dmpi->stride[0], 
				      mpi->planes[0]+mpi->stride[0],
				      mpi->w, mpi->h/2, 
				      dmpi->stride[0]*2, mpi->stride[0]*2);
			if (mpi->flags & MP_IMGFLAG_PLANAR) {
				my_memcpy_pic(dmpi->planes[1]+dmpi->stride[1], 
					      mpi->planes[1]+mpi->stride[1],
					      mpi->chroma_width, mpi->chroma_height/2,
					      dmpi->stride[1]*2, mpi->stride[1]*2);
				my_memcpy_pic(dmpi->planes[2]+dmpi->stride[2], 
					      mpi->planes[2]+mpi->stride[2],
					      mpi->chroma_width, mpi->chroma_height/2,
					      dmpi->stride[2]*2, mpi->stride[2]*2);
			}
			ret = vf_next_put_image(vf, dmpi, MP_NOPTS_VALUE);
		}
		break;
	}

	vf->priv->frame++;

	return ret;
}

static int query_format(struct vf_instance_s* vf, unsigned int fmt)
{
	/* FIXME - figure out which other formats work */
	switch (fmt) {
	case IMGFMT_YV12:
	case IMGFMT_IYUV:
	case IMGFMT_I420:
		return vf_next_query_format(vf, fmt);
	}
	return 0;
}

static int config(struct vf_instance_s* vf,
        int width, int height, int d_width, int d_height,
	unsigned int flags, unsigned int outfmt)
{
	switch (vf->priv->mode) {
	case 0:
	case 3:
		return vf_next_config(vf,width,height*2,d_width,d_height*2,flags,outfmt);
	case 1:			/* odd frames */
	case 2:			/* even frames */
	case 4:			/* alternate frame (height-preserving) interlacing */
		return vf_next_config(vf,width,height,d_width,d_height,flags,outfmt);
	}
	return 0;
}

static void uninit(struct vf_instance_s* vf)
{
	free(vf->priv);
}

static int open(vf_instance_t *vf, char* args)
{
	struct vf_priv_s *p;
	vf->config = config;
	vf->put_image = put_image;
	vf->query_format = query_format;
	vf->uninit = uninit;
	vf->default_reqs = VFCAP_ACCEPT_STRIDE;
	vf->priv = p = calloc(1, sizeof(struct vf_priv_s));
	vf->priv->mode = 0;
	if (args)
	  sscanf(args, "%d", &vf->priv->mode);
	vf->priv->frame = 0;
	return 1;
}

vf_info_t vf_info_tinterlace = {
	"temporal field interlacing",
	"tinterlace",
	"Michael Zucchi",
	"",
	open,
	NULL
};
