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

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

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

#include "libvo/video_out.h"

#include "m_option.h"
#include "m_struct.h"

static struct vf_priv_s {
	unsigned char *buf;
	float level1;
	float level2;
	float pos1;		// position to start changing chroma level to level1
	float pos2;		// position to start rolling off from level1 to level2
	float pos3;		// position to roll off to level2
	float pos4;		// position to changing chroma level to original
	int pixel_pos1;
	int pixel_pos2;
	int pixel_pos3;
	int pixel_pos4;
	float delta;
} const vf_priv_dflt = {
  NULL,
  0,
  0,
  0, 0, 0
};

static inline void process(unsigned char *dest, int dstride, unsigned char *src, int sstride, int w, int h, struct vf_priv_s* priv)
{
	int i;
	int dstep = dstride-w;
	int sstep = sstride-w;
	int pos1 = (int)priv->pixel_pos1;
	int pos2 = (int)priv->pixel_pos2;
	int pos3 = (int)priv->pixel_pos3;
	int pos4 = (int)priv->pixel_pos4;
	float delta = priv->delta;
	
	while (h--) {
		float level = priv->level1;
		for (i = 0; i < w; i++)
		{
			if (i >= pos1 && i < pos4) {
				if (i >= pos2 && i < pos3) level += delta;
				*dest++ = level * (*src++);
			} else {
				*dest++ = *src++;
			}
		}
		src += sstep;
		dest += dstep;
	}
}

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

	dmpi=vf_get_image(vf->next, mpi->imgfmt,
			  MP_IMGTYPE_EXPORT, 0,
			  mpi->w, mpi->h);
	
	dmpi->stride[0] = mpi->stride[0];
	dmpi->planes[1] = mpi->planes[1];
	dmpi->planes[2] = mpi->planes[2];
	dmpi->stride[1] = mpi->stride[1];
	dmpi->stride[2] = mpi->stride[2];

	if (!vf->priv->buf) vf->priv->buf = malloc(mpi->stride[0]*mpi->h);

	dmpi->planes[0] = vf->priv->buf;
	process(dmpi->planes[0], dmpi->stride[0],
		mpi->planes[0], mpi->stride[0],
		mpi->w, mpi->h, vf->priv);

	return vf_next_put_image(vf,dmpi, pts);
}

static int query_format(struct vf_instance_s* vf, unsigned int fmt)
{
	switch (fmt) {
	case IMGFMT_YVU9:
	case IMGFMT_IF09:
	case IMGFMT_YV12:
	case IMGFMT_I420:
	case IMGFMT_IYUV:
	case IMGFMT_CLPL:
	case IMGFMT_Y800:
	case IMGFMT_Y8:
	case IMGFMT_NV12:
	case IMGFMT_NV21:
	case IMGFMT_444P:
	case IMGFMT_422P:
	case IMGFMT_411P:
		return vf_next_query_format(vf, fmt);
	}
	return 0;
}

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

static int config(struct vf_instance_s* vf,
        int width, int height, int d_width, int d_height,
	unsigned int flags, unsigned int outfmt){

	// convert percentage to pixel
	vf->priv->pixel_pos1 = (int)(vf->priv->pos1 / 100 * width);
	vf->priv->pixel_pos2 = (int)(vf->priv->pos2 / 100 * width);
	vf->priv->pixel_pos3 = (int)(vf->priv->pos3 / 100 * width);
	vf->priv->pixel_pos4 = (int)(vf->priv->pos4 / 100 * width);
	vf->priv->delta = (vf->priv->level2 - vf->priv->level1) / (vf->priv->pixel_pos3 -vf->priv->pixel_pos2);

	mp_msg(MSGT_VFILTER, MSGL_INFO, "[Roll-off] l1: %f l2: %f p1: %d p2: %d p3: %d p4: %d\n",
		vf->priv->level1, vf->priv->level2, vf->priv->pixel_pos1, vf->priv->pixel_pos2, vf->priv->pixel_pos3, vf->priv->pixel_pos4);
	return vf_next_config(vf,width,height,d_width,d_height,flags,outfmt);
}

static int open(vf_instance_t *vf, char* args)
{
	vf->config=config;
	vf->query_format=query_format;
	vf->put_image=put_image;
	vf->uninit=uninit;
	
	return 1;
}

#define ST_OFF(f) M_ST_OFF(struct vf_priv_s,f)
static m_option_t vf_opts_fields[] = {
  {"level1", ST_OFF(level1), CONF_TYPE_FLOAT, M_OPT_RANGE, 0, 1, NULL},
  {"level2", ST_OFF(level2), CONF_TYPE_FLOAT, M_OPT_RANGE, 0, 1, NULL},
  {"pos1", ST_OFF(pos1), CONF_TYPE_FLOAT, M_OPT_RANGE, 0, 100, NULL},
  {"pos2", ST_OFF(pos2), CONF_TYPE_FLOAT, M_OPT_RANGE, 0 ,100, NULL},
  {"pos3", ST_OFF(pos3), CONF_TYPE_FLOAT, M_OPT_RANGE, 0 ,100, NULL},
  {"pos4", ST_OFF(pos4), CONF_TYPE_FLOAT, M_OPT_RANGE, 0 ,100, NULL},
  { NULL, NULL, 0, 0, 0, 0,  NULL }
};

static m_struct_t vf_opts = {
  "rolloff",
  sizeof(struct vf_priv_s),
  &vf_priv_dflt,
  vf_opts_fields
};

vf_info_t vf_info_rolloff = {
	"chroma roll-off filter",
	"rolloff",
	"Stanley Huang",
	"",
	open,
	&vf_opts
};