#include "mupdf/pdf.h"

typedef struct filter_gstate_s filter_gstate;

typedef enum
{
	FLUSH_CTM = 1,
	FLUSH_COLOR_F = 2,
	FLUSH_COLOR_S = 4,

	FLUSH_ALL = 7,
	FLUSH_STROKE = 1+4,
	FLUSH_FILL = 1+2
} gstate_flush_flags;

struct filter_gstate_s
{
	filter_gstate *next;
	int pushed;
	fz_matrix ctm;
	fz_matrix current_ctm;
	struct
	{
		char name[256];
		fz_colorspace *cs;
	} cs, CS, current_cs, current_CS;
	struct
	{
		char name[256];
		pdf_pattern *pat;
		fz_shade *shd;
		int n;
		float c[FZ_MAX_COLORS];
	} sc, SC, current_sc, current_SC;
	struct
	{
		fz_linecap linecap;
		fz_linejoin linejoin;
		float linewidth;
		float miterlimit;
	} stroke, current_stroke;
};

typedef struct pdf_filter_processor_s
{
	pdf_processor super;
	pdf_processor *chain;
	filter_gstate *gstate;
	pdf_document *doc;
	pdf_obj *old_rdb, *new_rdb;
} pdf_filter_processor;

static void
copy_resource(fz_context *ctx, pdf_filter_processor *p, pdf_obj *key, const char *name)
{
	pdf_obj *res, *obj;

	if (!name || name[0] == 0)
		return;

	res = pdf_dict_get(ctx, p->old_rdb, key);
	obj = pdf_dict_gets(ctx, res, name);
	if (obj)
	{
		res = pdf_dict_get(ctx, p->new_rdb, key);
		if (!res)
		{
			res = pdf_new_dict(ctx, p->doc, 1);
			pdf_dict_put_drop(ctx, p->new_rdb, key, res);
		}
		pdf_dict_putp(ctx, res, name, obj);
	}
}

static void
filter_push(fz_context *ctx, pdf_filter_processor *p)
{
	filter_gstate *gstate = p->gstate;
	filter_gstate *new_gstate = fz_malloc_struct(ctx, filter_gstate);
	*new_gstate = *gstate;
	new_gstate->pushed = 0;
	new_gstate->next = gstate;
	p->gstate = new_gstate;
}

static int
filter_pop(fz_context *ctx, pdf_filter_processor *p)
{
	filter_gstate *gstate = p->gstate;
	filter_gstate *old = gstate->next;

	/* We are at the top, so nothing to pop! */
	if (old == NULL)
		return 1;

	if (gstate->pushed)
		if (p->chain->op_Q)
			p->chain->op_Q(ctx, p->chain);

	fz_free(ctx, gstate);
	p->gstate = old;
	return 0;
}

/* We never allow the topmost gstate to be changed. This allows us
 * to pop back to the zeroth level and be sure that our gstate is
 * sane. This is important for being able to add new operators at
 * the end of pages in a sane way. */
static filter_gstate *
gstate_to_update(fz_context *ctx, pdf_filter_processor *p)
{
	filter_gstate *gstate = p->gstate;

	/* If we're not the top, that's fine */
	if (gstate->next != NULL)
		return gstate;

	/* We are the top. Push a group, so we're not */
	filter_push(ctx, p);
	gstate = p->gstate;
	gstate->pushed = 1;
	if (p->chain->op_q)
		p->chain->op_q(ctx, p->chain);

	return p->gstate;
}

static void filter_flush(fz_context *ctx, pdf_filter_processor *p, int flush)
{
	filter_gstate *gstate = gstate_to_update(ctx, p);
	int i;

	if (gstate->pushed == 0)
	{
		gstate->pushed = 1;
		if (p->chain->op_q)
			p->chain->op_q(ctx, p->chain);
	}

	if (flush & FLUSH_CTM)
	{
		if (gstate->ctm.a != 1 || gstate->ctm.b != 0 ||
			gstate->ctm.c != 0 || gstate->ctm.d != 1 ||
			gstate->ctm.e != 0 || gstate->ctm.f != 0)
		{
			fz_matrix current = gstate->current_ctm;

			if (p->chain->op_cm)
				p->chain->op_cm(ctx, p->chain,
					gstate->ctm.a,
					gstate->ctm.b,
					gstate->ctm.c,
					gstate->ctm.d,
					gstate->ctm.e,
					gstate->ctm.f);

			fz_concat(&gstate->current_ctm, &current, &gstate->ctm);
			gstate->ctm.a = 1;
			gstate->ctm.b = 0;
			gstate->ctm.c = 0;
			gstate->ctm.d = 1;
			gstate->ctm.e = 0;
			gstate->ctm.f = 0;
		}
	}

	if (flush & FLUSH_COLOR_F)
	{
		if (gstate->cs.cs == fz_device_gray(ctx) && !gstate->sc.pat && !gstate->sc.shd && gstate->sc.n == 1)
		{
			if (p->chain->op_g)
				p->chain->op_g(ctx, p->chain, gstate->sc.c[0]);
			goto done_sc;
		}
		if (gstate->cs.cs == fz_device_rgb(ctx) && !gstate->sc.pat && !gstate->sc.shd && gstate->sc.n == 3)
		{
			if (p->chain->op_rg)
				p->chain->op_rg(ctx, p->chain, gstate->sc.c[0], gstate->sc.c[1], gstate->sc.c[2]);
			goto done_sc;
		}
		if (gstate->cs.cs == fz_device_cmyk(ctx) && !gstate->sc.pat && !gstate->sc.shd && gstate->sc.n == 4)
		{
			if (p->chain->op_k)
				p->chain->op_k(ctx, p->chain, gstate->sc.c[0], gstate->sc.c[1], gstate->sc.c[2], gstate->sc.c[3]);
			goto done_sc;
		}

		if (strcmp(gstate->cs.name, gstate->current_cs.name))
		{
			if (p->chain->op_cs)
				p->chain->op_cs(ctx, p->chain, gstate->cs.name, gstate->cs.cs);
		}

		/* pattern or shading */
		if (gstate->sc.name[0])
		{
			int emit = 0;
			if (strcmp(gstate->sc.name, gstate->current_sc.name))
				emit = 1;
			if (gstate->sc.n != gstate->current_sc.n)
				emit = 1;
			else
				for (i = 0; i < gstate->sc.n; ++i)
					if (gstate->sc.c[i] != gstate->current_sc.c[i])
						emit = 1;
			if (emit)
			{
				if (gstate->sc.pat)
					if (p->chain->op_sc_pattern)
						p->chain->op_sc_pattern(ctx, p->chain, gstate->sc.name, gstate->sc.pat, gstate->sc.n, gstate->sc.c);
				if (gstate->sc.shd)
					if (p->chain->op_sc_shade)
						p->chain->op_sc_shade(ctx, p->chain, gstate->sc.name, gstate->sc.shd);
			}
		}

		/* plain color */
		else
		{
			int emit = 0;
			if (gstate->sc.n != gstate->current_sc.n)
				emit = 1;
			else
				for (i = 0; i < gstate->sc.n; ++i)
					if (gstate->sc.c[i] != gstate->current_sc.c[i])
						emit = 1;
			if (emit)
			{
				if (p->chain->op_sc_color)
					p->chain->op_sc_color(ctx, p->chain, gstate->sc.n, gstate->sc.c);
			}
		}

done_sc:
		gstate->current_cs = gstate->cs;
		gstate->current_sc = gstate->sc;
	}

	if (flush & FLUSH_COLOR_S)
	{
		if (gstate->CS.cs == fz_device_gray(ctx) && !gstate->SC.pat && !gstate->SC.shd && gstate->SC.n == 1)
		{
			if (p->chain->op_G)
				p->chain->op_G(ctx, p->chain, gstate->SC.c[0]);
			goto done_SC;
		}
		if (gstate->CS.cs == fz_device_rgb(ctx) && !gstate->SC.pat && !gstate->SC.shd && gstate->SC.n == 3)
		{
			if (p->chain->op_RG)
				p->chain->op_RG(ctx, p->chain, gstate->SC.c[0], gstate->SC.c[1], gstate->SC.c[2]);
			goto done_SC;
		}
		if (gstate->CS.cs == fz_device_cmyk(ctx) && !gstate->SC.pat && !gstate->SC.shd && gstate->SC.n == 4)
		{
			if (p->chain->op_K)
				p->chain->op_K(ctx, p->chain, gstate->SC.c[0], gstate->SC.c[1], gstate->SC.c[2], gstate->SC.c[3]);
			goto done_SC;
		}

		if (strcmp(gstate->CS.name, gstate->current_CS.name))
		{
			if (p->chain->op_CS)
				p->chain->op_CS(ctx, p->chain, gstate->CS.name, gstate->CS.cs);
		}

		/* pattern or shading */
		if (gstate->SC.name[0])
		{
			int emit = 0;
			if (strcmp(gstate->SC.name, gstate->current_SC.name))
				emit = 1;
			if (gstate->SC.n != gstate->current_SC.n)
				emit = 1;
			else
				for (i = 0; i < gstate->SC.n; ++i)
					if (gstate->SC.c[i] != gstate->current_SC.c[i])
						emit = 1;
			if (emit)
			{
				if (gstate->SC.pat)
					if (p->chain->op_SC_pattern)
						p->chain->op_SC_pattern(ctx, p->chain, gstate->SC.name, gstate->SC.pat, gstate->SC.n, gstate->SC.c);
				if (gstate->SC.shd)
					if (p->chain->op_SC_shade)
						p->chain->op_SC_shade(ctx, p->chain, gstate->SC.name, gstate->SC.shd);
			}
		}

		/* plain color */
		else
		{
			int emit = 0;
			if (gstate->SC.n != gstate->current_SC.n)
				emit = 1;
			else
				for (i = 0; i < gstate->SC.n; ++i)
					if (gstate->SC.c[i] != gstate->current_SC.c[i])
						emit = 1;
			if (emit)
			{
				if (p->chain->op_SC_color)
					p->chain->op_SC_color(ctx, p->chain, gstate->SC.n, gstate->SC.c);
			}
		}

done_SC:
		gstate->current_CS = gstate->CS;
		gstate->current_SC = gstate->SC;
	}

	if (flush & FLUSH_STROKE)
	{
		if (gstate->stroke.linecap != gstate->current_stroke.linecap)
		{
			if (p->chain->op_J)
				p->chain->op_J(ctx, p->chain, gstate->stroke.linecap);
		}
		if (gstate->stroke.linejoin != gstate->current_stroke.linejoin)
		{
			if (p->chain->op_j)
				p->chain->op_j(ctx, p->chain, gstate->stroke.linejoin);
		}
		if (gstate->stroke.linewidth != gstate->current_stroke.linewidth)
		{
			if (p->chain->op_w)
				p->chain->op_w(ctx, p->chain, gstate->stroke.linewidth);
		}
		if (gstate->stroke.miterlimit != gstate->current_stroke.miterlimit)
		{
			if (p->chain->op_M)
				p->chain->op_M(ctx, p->chain, gstate->stroke.linewidth);
		}
		gstate->current_stroke = gstate->stroke;
	}
}

/* general graphics state */

static void
pdf_filter_w(fz_context *ctx, pdf_processor *proc, float linewidth)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_gstate *gstate = gstate_to_update(ctx, p);
	gstate->stroke.linewidth = linewidth;
}

static void
pdf_filter_j(fz_context *ctx, pdf_processor *proc, int linejoin)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_gstate *gstate = gstate_to_update(ctx, p);
	gstate->stroke.linejoin = linejoin;
}

static void
pdf_filter_J(fz_context *ctx, pdf_processor *proc, int linecap)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_gstate *gstate = gstate_to_update(ctx, p);
	gstate->stroke.linecap = linecap;
}

static void
pdf_filter_M(fz_context *ctx, pdf_processor *proc, float miterlimit)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_gstate *gstate = gstate_to_update(ctx, p);
	gstate->stroke.miterlimit = miterlimit;
}

static void
pdf_filter_d(fz_context *ctx, pdf_processor *proc, pdf_obj *array, float phase)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_d)
		p->chain->op_d(ctx, p->chain, array, phase);
}

static void
pdf_filter_ri(fz_context *ctx, pdf_processor *proc, const char *intent)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_ri)
		p->chain->op_ri(ctx, p->chain, intent);
}

static void
pdf_filter_i(fz_context *ctx, pdf_processor *proc, float flatness)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_i)
		p->chain->op_i(ctx, p->chain, flatness);
}

static void
pdf_filter_gs_begin(fz_context *ctx, pdf_processor *proc, const char *name, pdf_obj *extgstate)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_ALL);
	if (p->chain->op_gs_begin)
		p->chain->op_gs_begin(ctx, p->chain, name, extgstate);
	copy_resource(ctx, p, PDF_NAME_ExtGState, name);
}

static void
pdf_filter_gs_BM(fz_context *ctx, pdf_processor *proc, const char *blendmode)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	if (p->chain->op_gs_BM)
		p->chain->op_gs_BM(ctx, p->chain, blendmode);
}

static void
pdf_filter_gs_CA(fz_context *ctx, pdf_processor *proc, float alpha)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	if (p->chain->op_gs_CA)
		p->chain->op_gs_CA(ctx, p->chain, alpha);
}

static void
pdf_filter_gs_ca(fz_context *ctx, pdf_processor *proc, float alpha)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	if (p->chain->op_gs_ca)
		p->chain->op_gs_ca(ctx, p->chain, alpha);
}

static void
pdf_filter_gs_SMask(fz_context *ctx, pdf_processor *proc, pdf_xobject *smask, pdf_obj *page_resources, float *bc, int luminosity)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	if (p->chain->op_gs_SMask)
		p->chain->op_gs_SMask(ctx, p->chain, smask, page_resources, bc, luminosity);
}

static void
pdf_filter_gs_end(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	if (p->chain->op_gs_end)
		p->chain->op_gs_end(ctx, p->chain);
}

/* special graphics state */

static void
pdf_filter_q(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_push(ctx, p);
}

static void
pdf_filter_Q(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_pop(ctx, p);
}

static void
pdf_filter_cm(fz_context *ctx, pdf_processor *proc, float a, float b, float c, float d, float e, float f)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_gstate *gstate = gstate_to_update(ctx, p);
	fz_matrix old, ctm;

	/* If we're being given an identity matrix, don't bother sending it */
	if (a == 1 && b == 0 && c == 0 && d == 1 && e == 0 && f == 0)
		return;

	ctm.a = a;
	ctm.b = b;
	ctm.c = c;
	ctm.d = d;
	ctm.e = e;
	ctm.f = f;

	old = gstate->ctm;
	fz_concat(&gstate->ctm, &ctm, &old);
}

/* path construction */

static void
pdf_filter_m(fz_context *ctx, pdf_processor *proc, float x, float y)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_m)
		p->chain->op_m(ctx, p->chain, x, y);
}

static void
pdf_filter_l(fz_context *ctx, pdf_processor *proc, float x, float y)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_l)
		p->chain->op_l(ctx, p->chain, x, y);
}

static void
pdf_filter_c(fz_context *ctx, pdf_processor *proc, float x1, float y1, float x2, float y2, float x3, float y3)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_c)
		p->chain->op_c(ctx, p->chain, x1, y1, x2, y2, x3, y3);
}

static void
pdf_filter_v(fz_context *ctx, pdf_processor *proc, float x2, float y2, float x3, float y3)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_v)
		p->chain->op_v(ctx, p->chain, x2, y2, x3, y3);
}

static void
pdf_filter_y(fz_context *ctx, pdf_processor *proc, float x1, float y1, float x3, float y3)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_y)
		p->chain->op_y(ctx, p->chain, x1, y1, x3, y3);
}

static void
pdf_filter_h(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_h)
		p->chain->op_h(ctx, p->chain);
}

static void
pdf_filter_re(fz_context *ctx, pdf_processor *proc, float x, float y, float w, float h)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_re)
		p->chain->op_re(ctx, p->chain, x, y, w, h);
}

/* path painting */

static void
pdf_filter_S(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_STROKE);
	if (p->chain->op_S)
		p->chain->op_S(ctx, p->chain);
}

static void
pdf_filter_s(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_STROKE);
	if (p->chain->op_s)
		p->chain->op_s(ctx, p->chain);
}

static void
pdf_filter_F(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_FILL);
	if (p->chain->op_F)
		p->chain->op_F(ctx, p->chain);
}

static void
pdf_filter_f(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_FILL);
	if (p->chain->op_f)
		p->chain->op_f(ctx, p->chain);
}

static void
pdf_filter_fstar(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_FILL);
	if (p->chain->op_fstar)
		p->chain->op_fstar(ctx, p->chain);
}

static void
pdf_filter_B(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_ALL);
	if (p->chain->op_B)
		p->chain->op_B(ctx, p->chain);
}

static void
pdf_filter_Bstar(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_ALL);
	if (p->chain->op_Bstar)
		p->chain->op_Bstar(ctx, p->chain);
}

static void
pdf_filter_b(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_ALL);
	if (p->chain->op_b)
		p->chain->op_b(ctx, p->chain);
}

static void
pdf_filter_bstar(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_ALL);
	if (p->chain->op_bstar)
		p->chain->op_bstar(ctx, p->chain);
}

static void
pdf_filter_n(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_n)
		p->chain->op_n(ctx, p->chain);
}

/* clipping paths */

static void
pdf_filter_W(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_W)
		p->chain->op_W(ctx, p->chain);
}

static void
pdf_filter_Wstar(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_Wstar)
		p->chain->op_Wstar(ctx, p->chain);
}

/* text objects */

static void
pdf_filter_BT(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_BT)
		p->chain->op_BT(ctx, p->chain);
}

static void
pdf_filter_ET(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_ET)
		p->chain->op_ET(ctx, p->chain);
}

/* text state */

static void
pdf_filter_Tc(fz_context *ctx, pdf_processor *proc, float charspace)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_Tc)
		p->chain->op_Tc(ctx, p->chain, charspace);
}

static void
pdf_filter_Tw(fz_context *ctx, pdf_processor *proc, float wordspace)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_Tw)
		p->chain->op_Tw(ctx, p->chain, wordspace);
}

static void
pdf_filter_Tz(fz_context *ctx, pdf_processor *proc, float scale)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_Tz)
		p->chain->op_Tz(ctx, p->chain, scale);
}

static void
pdf_filter_TL(fz_context *ctx, pdf_processor *proc, float leading)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_TL)
		p->chain->op_TL(ctx, p->chain, leading);
}

static void
pdf_filter_Tf(fz_context *ctx, pdf_processor *proc, const char *name, pdf_font_desc *font, float size)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_Tf)
		p->chain->op_Tf(ctx, p->chain, name, font, size);
	copy_resource(ctx, p, PDF_NAME_Font, name);
}

static void
pdf_filter_Tr(fz_context *ctx, pdf_processor *proc, int render)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_Tr)
		p->chain->op_Tr(ctx, p->chain, render);
}

static void
pdf_filter_Ts(fz_context *ctx, pdf_processor *proc, float rise)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_Ts)
		p->chain->op_Ts(ctx, p->chain, rise);
}

/* text positioning */

static void
pdf_filter_Td(fz_context *ctx, pdf_processor *proc, float tx, float ty)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_Td)
		p->chain->op_Td(ctx, p->chain, tx, ty);
}

static void
pdf_filter_TD(fz_context *ctx, pdf_processor *proc, float tx, float ty)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_TD)
		p->chain->op_TD(ctx, p->chain, tx, ty);
}

static void
pdf_filter_Tm(fz_context *ctx, pdf_processor *proc, float a, float b, float c, float d, float e, float f)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_Tm)
		p->chain->op_Tm(ctx, p->chain, a, b, c, d, e, f);
}

static void
pdf_filter_Tstar(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_CTM);
	if (p->chain->op_Tstar)
		p->chain->op_Tstar(ctx, p->chain);
}

/* text showing */

static void
pdf_filter_TJ(fz_context *ctx, pdf_processor *proc, pdf_obj *array)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_ALL);
	if (p->chain->op_TJ)
		p->chain->op_TJ(ctx, p->chain, array);
}

static void
pdf_filter_Tj(fz_context *ctx, pdf_processor *proc, char *str, int len)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_ALL);
	if (p->chain->op_Tj)
		p->chain->op_Tj(ctx, p->chain, str, len);
}

static void
pdf_filter_squote(fz_context *ctx, pdf_processor *proc, char *str, int len)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_ALL);
	if (p->chain->op_squote)
		p->chain->op_squote(ctx, p->chain, str, len);
}

static void
pdf_filter_dquote(fz_context *ctx, pdf_processor *proc, float aw, float ac, char *str, int len)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_ALL);
	if (p->chain->op_dquote)
		p->chain->op_dquote(ctx, p->chain, aw, ac, str, len);
}

/* type 3 fonts */

static void
pdf_filter_d0(fz_context *ctx, pdf_processor *proc, float wx, float wy)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_d0)
		p->chain->op_d0(ctx, p->chain, wx, wy);
}

static void
pdf_filter_d1(fz_context *ctx, pdf_processor *proc, float wx, float wy, float llx, float lly, float urx, float ury)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_d1)
		p->chain->op_d1(ctx, p->chain, wx, wy, llx, lly, urx, ury);
}

/* color */

static void
pdf_filter_CS(fz_context *ctx, pdf_processor *proc, const char *name, fz_colorspace *cs)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_gstate *gstate = gstate_to_update(ctx, p);
	fz_strlcpy(gstate->CS.name, name, sizeof gstate->CS.name);
	gstate->CS.cs = cs;
	copy_resource(ctx, p, PDF_NAME_ColorSpace, name);
}

static void
pdf_filter_cs(fz_context *ctx, pdf_processor *proc, const char *name, fz_colorspace *cs)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_gstate *gstate = gstate_to_update(ctx, p);
	fz_strlcpy(gstate->cs.name, name, sizeof gstate->cs.name);
	gstate->cs.cs = cs;
	copy_resource(ctx, p, PDF_NAME_ColorSpace, name);
}

static void
pdf_filter_SC_pattern(fz_context *ctx, pdf_processor *proc, const char *name, pdf_pattern *pat, int n, float *color)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_gstate *gstate = gstate_to_update(ctx, p);
	int i;
	fz_strlcpy(gstate->SC.name, name, sizeof gstate->SC.name);
	gstate->SC.pat = pat;
	gstate->SC.shd = NULL;
	gstate->SC.n = n;
	for (i = 0; i < n; ++i)
		gstate->SC.c[i] = color[i];
	copy_resource(ctx, p, PDF_NAME_Pattern, name);
}

static void
pdf_filter_sc_pattern(fz_context *ctx, pdf_processor *proc, const char *name, pdf_pattern *pat, int n, float *color)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_gstate *gstate = gstate_to_update(ctx, p);
	int i;
	fz_strlcpy(gstate->sc.name, name, sizeof gstate->sc.name);
	gstate->sc.pat = pat;
	gstate->sc.shd = NULL;
	gstate->sc.n = n;
	for (i = 0; i < n; ++i)
		gstate->sc.c[i] = color[i];
	copy_resource(ctx, p, PDF_NAME_Pattern, name);
}

static void
pdf_filter_SC_shade(fz_context *ctx, pdf_processor *proc, const char *name, fz_shade *shade)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_gstate *gstate = gstate_to_update(ctx, p);
	fz_strlcpy(gstate->SC.name, name, sizeof gstate->SC.name);
	gstate->SC.pat = NULL;
	gstate->SC.shd = shade;
	gstate->SC.n = 0;
	copy_resource(ctx, p, PDF_NAME_Pattern, name);
}

static void
pdf_filter_sc_shade(fz_context *ctx, pdf_processor *proc, const char *name, fz_shade *shade)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_gstate *gstate = gstate_to_update(ctx, p);
	fz_strlcpy(gstate->sc.name, name, sizeof gstate->sc.name);
	gstate->sc.pat = NULL;
	gstate->sc.shd = shade;
	gstate->sc.n = 0;
	copy_resource(ctx, p, PDF_NAME_Pattern, name);
}

static void
pdf_filter_SC_color(fz_context *ctx, pdf_processor *proc, int n, float *color)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_gstate *gstate = gstate_to_update(ctx, p);
	int i;
	gstate->SC.name[0] = 0;
	gstate->SC.pat = NULL;
	gstate->SC.shd = NULL;
	gstate->SC.n = n;
	for (i = 0; i < n; ++i)
		gstate->SC.c[i] = color[i];
}

static void
pdf_filter_sc_color(fz_context *ctx, pdf_processor *proc, int n, float *color)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_gstate *gstate = gstate_to_update(ctx, p);
	int i;
	gstate->sc.name[0] = 0;
	gstate->sc.pat = NULL;
	gstate->sc.shd = NULL;
	gstate->sc.n = n;
	for (i = 0; i < n; ++i)
		gstate->sc.c[i] = color[i];
}

static void
pdf_filter_G(fz_context *ctx, pdf_processor *proc, float g)
{
	float color[1] = { g };
	pdf_filter_CS(ctx, proc, "DeviceGray", fz_device_gray(ctx));
	pdf_filter_SC_color(ctx, proc, 1, color);
}

static void
pdf_filter_g(fz_context *ctx, pdf_processor *proc, float g)
{
	float color[1] = { g };
	pdf_filter_cs(ctx, proc, "DeviceGray", fz_device_gray(ctx));
	pdf_filter_sc_color(ctx, proc, 1, color);
}

static void
pdf_filter_RG(fz_context *ctx, pdf_processor *proc, float r, float g, float b)
{
	float color[3] = { r, g, b };
	pdf_filter_CS(ctx, proc, "DeviceRGB", fz_device_rgb(ctx));
	pdf_filter_SC_color(ctx, proc, 3, color);
}

static void
pdf_filter_rg(fz_context *ctx, pdf_processor *proc, float r, float g, float b)
{
	float color[3] = { r, g, b };
	pdf_filter_cs(ctx, proc, "DeviceRGB", fz_device_rgb(ctx));
	pdf_filter_sc_color(ctx, proc, 3, color);
}

static void
pdf_filter_K(fz_context *ctx, pdf_processor *proc, float c, float m, float y, float k)
{
	float color[4] = { c, m, y, k };
	pdf_filter_CS(ctx, proc, "DeviceCMYK", fz_device_cmyk(ctx));
	pdf_filter_SC_color(ctx, proc, 4, color);
}

static void
pdf_filter_k(fz_context *ctx, pdf_processor *proc, float c, float m, float y, float k)
{
	float color[4] = { c, m, y, k };
	pdf_filter_cs(ctx, proc, "DeviceCMYK", fz_device_cmyk(ctx));
	pdf_filter_sc_color(ctx, proc, 4, color);
}

/* shadings, images, xobjects */

static void
pdf_filter_BI(fz_context *ctx, pdf_processor *proc, fz_image *img)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_ALL);
	if (p->chain->op_BI)
		p->chain->op_BI(ctx, p->chain, img);
}

static void
pdf_filter_sh(fz_context *ctx, pdf_processor *proc, const char *name, fz_shade *shade)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_ALL);
	if (p->chain->op_sh)
		p->chain->op_sh(ctx, p->chain, name, shade);
	copy_resource(ctx, p, PDF_NAME_Shading, name);
}

static void
pdf_filter_Do_image(fz_context *ctx, pdf_processor *proc, const char *name, fz_image *image)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_ALL);
	if (p->chain->op_Do_image)
		p->chain->op_Do_image(ctx, p->chain, name, image);
	copy_resource(ctx, p, PDF_NAME_XObject, name);
}

static void
pdf_filter_Do_form(fz_context *ctx, pdf_processor *proc, const char *name, pdf_xobject *xobj, pdf_obj *page_resources)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, FLUSH_ALL);
	if (p->chain->op_Do_form)
		p->chain->op_Do_form(ctx, p->chain, name, xobj, page_resources);
	copy_resource(ctx, p, PDF_NAME_XObject, name);
}

/* marked content */

static void
pdf_filter_MP(fz_context *ctx, pdf_processor *proc, const char *tag)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_MP)
		p->chain->op_MP(ctx, p->chain, tag);
}

static void
pdf_filter_DP(fz_context *ctx, pdf_processor *proc, const char *tag, pdf_obj *raw, pdf_obj *cooked)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_DP)
		p->chain->op_DP(ctx, p->chain, tag, raw, cooked);
}

static void
pdf_filter_BMC(fz_context *ctx, pdf_processor *proc, const char *tag)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_BMC)
		p->chain->op_BMC(ctx, p->chain, tag);
}

static void
pdf_filter_BDC(fz_context *ctx, pdf_processor *proc, const char *tag, pdf_obj *raw, pdf_obj *cooked)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_BDC)
		p->chain->op_BDC(ctx, p->chain, tag, raw, cooked);
}

static void
pdf_filter_EMC(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_EMC)
		p->chain->op_EMC(ctx, p->chain);
}

/* compatibility */

static void
pdf_filter_BX(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_BX)
		p->chain->op_BX(ctx, p->chain);
}

static void
pdf_filter_EX(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	filter_flush(ctx, p, 0);
	if (p->chain->op_EX)
		p->chain->op_EX(ctx, p->chain);
}

static void
pdf_filter_END(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	while (!filter_pop(ctx, p))
	{
		/* Nothing to do in the loop, all work done above */
	}
}

static void
pdf_drop_imp_filter_processor(fz_context *ctx, pdf_processor *proc)
{
	pdf_filter_processor *p = (pdf_filter_processor*)proc;
	fz_free(ctx, p->gstate);
}

pdf_processor *
pdf_new_filter_processor(fz_context *ctx, pdf_processor *chain, pdf_document *doc, pdf_obj *old_rdb, pdf_obj *new_rdb)
{

	pdf_filter_processor *proc = pdf_new_processor(ctx, sizeof *proc);
	{
		proc->super.drop_imp = pdf_drop_imp_filter_processor;

		/* general graphics state */
		proc->super.op_w = pdf_filter_w;
		proc->super.op_j = pdf_filter_j;
		proc->super.op_J = pdf_filter_J;
		proc->super.op_M = pdf_filter_M;
		proc->super.op_d = pdf_filter_d;
		proc->super.op_ri = pdf_filter_ri;
		proc->super.op_i = pdf_filter_i;
		proc->super.op_gs_begin = pdf_filter_gs_begin;
		proc->super.op_gs_end = pdf_filter_gs_end;

		/* transparency graphics state */
		proc->super.op_gs_BM = pdf_filter_gs_BM;
		proc->super.op_gs_CA = pdf_filter_gs_CA;
		proc->super.op_gs_ca = pdf_filter_gs_ca;
		proc->super.op_gs_SMask = pdf_filter_gs_SMask;

		/* special graphics state */
		proc->super.op_q = pdf_filter_q;
		proc->super.op_Q = pdf_filter_Q;
		proc->super.op_cm = pdf_filter_cm;

		/* path construction */
		proc->super.op_m = pdf_filter_m;
		proc->super.op_l = pdf_filter_l;
		proc->super.op_c = pdf_filter_c;
		proc->super.op_v = pdf_filter_v;
		proc->super.op_y = pdf_filter_y;
		proc->super.op_h = pdf_filter_h;
		proc->super.op_re = pdf_filter_re;

		/* path painting */
		proc->super.op_S = pdf_filter_S;
		proc->super.op_s = pdf_filter_s;
		proc->super.op_F = pdf_filter_F;
		proc->super.op_f = pdf_filter_f;
		proc->super.op_fstar = pdf_filter_fstar;
		proc->super.op_B = pdf_filter_B;
		proc->super.op_Bstar = pdf_filter_Bstar;
		proc->super.op_b = pdf_filter_b;
		proc->super.op_bstar = pdf_filter_bstar;
		proc->super.op_n = pdf_filter_n;

		/* clipping paths */
		proc->super.op_W = pdf_filter_W;
		proc->super.op_Wstar = pdf_filter_Wstar;

		/* text objects */
		proc->super.op_BT = pdf_filter_BT;
		proc->super.op_ET = pdf_filter_ET;

		/* text state */
		proc->super.op_Tc = pdf_filter_Tc;
		proc->super.op_Tw = pdf_filter_Tw;
		proc->super.op_Tz = pdf_filter_Tz;
		proc->super.op_TL = pdf_filter_TL;
		proc->super.op_Tf = pdf_filter_Tf;
		proc->super.op_Tr = pdf_filter_Tr;
		proc->super.op_Ts = pdf_filter_Ts;

		/* text positioning */
		proc->super.op_Td = pdf_filter_Td;
		proc->super.op_TD = pdf_filter_TD;
		proc->super.op_Tm = pdf_filter_Tm;
		proc->super.op_Tstar = pdf_filter_Tstar;

		/* text showing */
		proc->super.op_TJ = pdf_filter_TJ;
		proc->super.op_Tj = pdf_filter_Tj;
		proc->super.op_squote = pdf_filter_squote;
		proc->super.op_dquote = pdf_filter_dquote;

		/* type 3 fonts */
		proc->super.op_d0 = pdf_filter_d0;
		proc->super.op_d1 = pdf_filter_d1;

		/* color */
		proc->super.op_CS = pdf_filter_CS;
		proc->super.op_cs = pdf_filter_cs;
		proc->super.op_SC_color = pdf_filter_SC_color;
		proc->super.op_sc_color = pdf_filter_sc_color;
		proc->super.op_SC_pattern = pdf_filter_SC_pattern;
		proc->super.op_sc_pattern = pdf_filter_sc_pattern;
		proc->super.op_SC_shade = pdf_filter_SC_shade;
		proc->super.op_sc_shade = pdf_filter_sc_shade;

		proc->super.op_G = pdf_filter_G;
		proc->super.op_g = pdf_filter_g;
		proc->super.op_RG = pdf_filter_RG;
		proc->super.op_rg = pdf_filter_rg;
		proc->super.op_K = pdf_filter_K;
		proc->super.op_k = pdf_filter_k;

		/* shadings, images, xobjects */
		proc->super.op_BI = pdf_filter_BI;
		proc->super.op_sh = pdf_filter_sh;
		proc->super.op_Do_image = pdf_filter_Do_image;
		proc->super.op_Do_form = pdf_filter_Do_form;

		/* marked content */
		proc->super.op_MP = pdf_filter_MP;
		proc->super.op_DP = pdf_filter_DP;
		proc->super.op_BMC = pdf_filter_BMC;
		proc->super.op_BDC = pdf_filter_BDC;
		proc->super.op_EMC = pdf_filter_EMC;

		/* compatibility */
		proc->super.op_BX = pdf_filter_BX;
		proc->super.op_EX = pdf_filter_EX;

		proc->super.op_END = pdf_filter_END;
	}

	proc->chain = chain;
	proc->doc = doc;
	proc->old_rdb = old_rdb;
	proc->new_rdb = new_rdb;

	proc->gstate = fz_malloc_struct(ctx, filter_gstate);
	proc->gstate->ctm = fz_identity;
	proc->gstate->current_ctm = fz_identity;

	proc->gstate->stroke = proc->gstate->stroke;
	proc->gstate->current_stroke = proc->gstate->stroke;

	return (pdf_processor*)proc;
}
