/*************************************************************************
 * Copyright (c) 2011 AT&T Intellectual Property 
 * All rights reserved. This program and the accompanying materials
 * are made available under the terms of the Eclipse Public License v1.0
 * which accompanies this distribution, and is available at
 * https://www.eclipse.org/legal/epl-v10.html
 *
 * Contributors: Details at https://graphviz.org
 *************************************************************************/

/*

XDOT DRAWING FUNCTIONS, maybe need to move them somewhere else
		for now keep them at the bottom
*/
#include "draw.h"
#include <common/colorprocs.h>
#include "smyrna_utils.h"
#include <glcomp/glutils.h>
#include <math.h>
#include <stdbool.h>
#include <stddef.h>
#include <stdlib.h>
#include <string.h>
#include <util/unreachable.h>
#include <util/list.h>
#include <util/xml.h>

#include <xdot/xdot.h>
#include "viewport.h"
#include "topfisheyeview.h"
#include "gui/appmouse.h"
#include "hotkeymap.h"
#include "polytess.h"
#include <glcomp/glcompimage.h>


//delta values
static float dx = 0.0;
static float dy = 0.0;
#define LAYER_DIFF 0.001

static void DrawBezier(xdot_point* pts, int filled, int param)
{
    /*copied from NEHE */
    /*Written by: David Nikdel ( ogapo@ithink.net ) */
    double Ax = pts[0].x;
    double Ay = pts[0].y;
    double Az = pts[0].z;
    double Bx = pts[1].x;
    double By = pts[1].y;
    double Bz = pts[1].z;
    double Cx = pts[2].x;
    double Cy = pts[2].y;
    double Cz = pts[2].z;
    double Dx = pts[3].x;
    double Dy = pts[3].y;
    double Dz = pts[3].z;
    double X;
    double Y;
    double Z;
    int i = 0;			//loop index
    // Variable
    double a = 1.0;
    double b = 1.0 - a;
    /* Tell OGL to start drawing a line strip */
    glLineWidth(view->LineWidth);
    if (!filled) {

	if (param == 0)
	    glColor4d(view->penColor.R, view->penColor.G, view->penColor.B,
		      view->penColor.A);
	else if (param == 1)		//selected
	    glColor4d(view->selectedNodeColor.R, view->selectedNodeColor.G,
		      view->selectedNodeColor.B,
		      view->selectedNodeColor.A);
	glBegin(GL_LINE_STRIP);
    } else {
	if (param == 0)
	    glColor4d(view->fillColor.R, view->fillColor.G,
		      view->fillColor.B, view->penColor.A);
	else if (param == 1)		//selected
	    glColor4d(view->selectedNodeColor.R, view->selectedNodeColor.G,
		      view->selectedNodeColor.B,
		      view->selectedNodeColor.A);
	glBegin(GL_POLYGON);
    }
    /* We will not actually draw a curve, but we will divide the curve into small
       points and draw a line between each point. If the points are close enough, it
       will appear as a curved line. 20 points are plenty, and since the variable goes
       from 1.0 to 0.0 we must change it by 1/20 = 0.05 each time */
    for (i = 0; i <= 20; i++) {
	// Get a point on the curve
	X = Ax * a * a * a + Bx * 3 * a * a * b + Cx * 3 * a * b * b +
	    Dx * b * b * b;
	Y = Ay * a * a * a + By * 3 * a * a * b + Cy * 3 * a * b * b +
	    Dy * b * b * b;
	Z = Az * a * a * a + Bz * 3 * a * a * b + Cz * 3 * a * b * b +
	    Dz * b * b * b;
	// Draw the line from point to point (assuming OGL is set up properly)
	glVertex3d(X, Y, Z + view->Topview->global_z);
	// Change the variable
	a -= 0.05;
	b = 1.0 - a;
    }
// Tell OGL to stop drawing the line strip
    glEnd();
}

static void set_options(int param)
{

    int a=get_mode(view);
    if (param == 1 && a == 10 && view->mouse.down) // selected, if there is move, move it
    {
	dx = view->mouse.GLinitPos.x-view->mouse.GLfinalPos.x;
	dy = view->mouse.GLinitPos.y-view->mouse.GLfinalPos.y;
    } else {
	dx = 0;
	dy = 0;
    }

}

static void DrawBeziers(xdot_op *op, int param) {
    sdot_op *const o = (sdot_op *)((char *)op - offsetof(sdot_op, op));
    xdot_point* ps = op->u.bezier.pts;
    view->Topview->global_z += o->layer * LAYER_DIFF;

    const int filled = op->kind == xd_filled_bezier;

    for (size_t i = 1; i < op->u.bezier.cnt; i += 3) {
	DrawBezier(ps, filled, param);
	ps += 3;
    }
}

//Draws an ellipse made out of points.
static void DrawEllipse(xdot_op *op, int param) {
    sdot_op *const o = (sdot_op *)((char *)op - offsetof(sdot_op, op));
    int filled;
    view->Topview->global_z += o->layer * LAYER_DIFF;
    set_options(param);
    double x = op->u.ellipse.x - dx;
    double y = op->u.ellipse.y - dy;
    double xradius = op->u.ellipse.w;
    double yradius = op->u.ellipse.h;
    if (op->kind == xd_filled_ellipse) {
	if (param == 0)
	    glColor4d(view->fillColor.R, view->fillColor.G,
		      view->fillColor.B, view->fillColor.A);
	if (param == 1)		//selected
	    glColor4d(view->selectedNodeColor.R, view->selectedNodeColor.G,
		      view->selectedNodeColor.B,
		      view->selectedNodeColor.A);

	filled = 1;
    } else {
	if (param == 0)
	    glColor4d(view->penColor.R, view->penColor.G, view->penColor.B,
		      view->penColor.A);
	if (param == 1)		//selected
	    glColor4d(view->selectedNodeColor.R, view->selectedNodeColor.G,
		      view->selectedNodeColor.B,
		      view->selectedNodeColor.A);

	filled = 0;
    }

    if (!filled)
	glBegin(GL_LINE_LOOP);
    else
	glBegin(GL_POLYGON);
    for (int i = 0; i < 360; ++i) {
	//convert degrees into radians
	const double degInRad = i * DEG2RAD;
	glVertex3d(x + cos(degInRad) * xradius,
		   y + sin(degInRad) * yradius, view->Topview->global_z);
    }
    glEnd();
}

static void DrawPolygon(xdot_op *op, int param) {
    sdot_op *const o = (sdot_op *)((char *)op - offsetof(sdot_op, op));
    view->Topview->global_z += o->layer * LAYER_DIFF;

    set_options(param);

    if (op->kind == xd_filled_polygon) {
	if (param == 0)
	    glColor4d(view->fillColor.R, view->fillColor.G,
		      view->fillColor.B, view->fillColor.A);
	if (param == 1)		//selected
	    glColor4d(view->selectedNodeColor.R, view->selectedNodeColor.G,
		      view->selectedNodeColor.B,
		      view->selectedNodeColor.A);
    } else {
	if (param == 0)
	    glColor4d(view->penColor.R, view->penColor.G, view->penColor.B,
		      view->penColor.A);
	if (param == 1)		//selected
	    glColor4d(view->selectedNodeColor.R, view->selectedNodeColor.G,
		      view->selectedNodeColor.B,
		      view->selectedNodeColor.A);

    }
    glLineWidth(view->LineWidth);
    drawTessPolygon(o);
}

static void DrawPolyline(xdot_op *op, int param) {
    sdot_op *const o = (sdot_op *)((char *)op - offsetof(sdot_op, op));
    view->Topview->global_z += o->layer * LAYER_DIFF;

    if (param == 0)
	glColor4d(view->penColor.R, view->penColor.G, view->penColor.B,
		  view->penColor.A);
    if (param == 1)		//selected
	glColor4d(view->selectedNodeColor.R, view->selectedNodeColor.G,
		  view->selectedNodeColor.B, view->selectedNodeColor.A);
    set_options(param);
    glLineWidth(view->LineWidth);
    glBegin(GL_LINE_STRIP);
    for (size_t i = 0; i < op->u.polyline.cnt; ++i) {
	glVertex3d(op->u.polyline.pts[i].x - dx,
		   op->u.polyline.pts[i].y - dy,
		   op->u.polyline.pts[i].z + view->Topview->global_z);
    }
    glEnd();
}

static glCompColor GetglCompColor(const char *color) {
    gvcolor_t cl;
    glCompColor c;
    if (color != NULL) {
	colorxlate(color, &cl, RGBA_DOUBLE);
	c.R = cl.u.RGBA[0];
	c.G = cl.u.RGBA[1];
	c.B = cl.u.RGBA[2];
	c.A = cl.u.RGBA[3];
    } else {
	c = view->penColor;
    }
    return c;
}

static void SetFillColor(xdot_op *op, int param) {
    (void)param;
    view->fillColor = GetglCompColor(op->u.color);
}

static void SetPenColor(xdot_op *op, int param) {
    (void)param;
    view->penColor = GetglCompColor(op->u.color);
}

static sdot_op * font_op;

static void SetFont(xdot_op *op, int param) {
	sdot_op *const o = (sdot_op *)((char *)op - offsetof(sdot_op, op));
	(void)param;

	font_op=o;
}

/*for now we only support png files in 2d space, no image rotation*/
static void InsertImage(xdot_op *op, int param) {
    sdot_op *const o = (sdot_op *)((char *)op - offsetof(sdot_op, op));
    (void)param;

    if(!o->obj)
	return;


    if(!o->img) {
	const float x = o->op.u.image.pos.x;
	const float y = o->op.u.image.pos.y;
	glCompImage *const i = o->img = glCompImageNewFile(x, y, o->op.u.image.name);
	if (!o->img) {
	    fprintf (stderr, "Could not open file \"%s\" to read image.\n", o->op.u.image.name);
	    return;
	}
	i->width = o->op.u.image.pos.w;
	i->height = o->op.u.image.pos.h;
	i->base.common.functions.draw(i);
    }
}

// see usage in EmbedText
static int put(void *buffer, const char *s) {
  char **b = buffer;

  const size_t len = strlen(s);
  memcpy(*b, s, len);
  *b += len;

  return 0;
}

static void EmbedText(xdot_op *op, int param) {
	sdot_op *const o = (sdot_op *)((char *)op - offsetof(sdot_op, op));
	(void)param;

	float x, y;
	glColor4d(view->penColor.R,view->penColor.G,view->penColor.B,view->penColor.A);
	view->Topview->global_z += o->layer * LAYER_DIFF + 0.05;
	switch (o->op.u.text.align)
	{
		case xd_left:
			x=o->op.u.text.x ;
			break;
		case xd_center:
			x=o->op.u.text.x - o->op.u.text.width / 2.0;
			break;
		case xd_right:
			x=o->op.u.text.x - o->op.u.text.width;
			break;
		default:
			UNREACHABLE();
	}
	y=o->op.u.text.y;
	if (o->font.fontdesc == NULL) {
		// allocate a buffer large enough to hold the maximum escaped version of the
		// text
		char *escaped = calloc(sizeof(char), strlen(o->op.u.text.text) *
		                                     sizeof("&#xFFFFFFFF;") + 1);
		if (escaped == NULL)
		  return;

		// XML-escape the text
		const xml_flags_t flags = {.dash = 1, .nbsp = 1};
		char *ptr = escaped;
		(void)gv_xml_escape(o->op.u.text.text, flags, put, &ptr);

		o->font = glNewFont(view->widgets, escaped, &view->penColor,
		                    font_op->op.u.font.name, font_op->op.u.font.size,
		                    false);

		free(escaped);
	}
	glCompDrawText3D(o->font, x, y, view->Topview->global_z, o->op.u.text.width,
	                 font_op->op.u.font.size);
}

void drawBorders(ViewInfo * vi)
{
    if (vi->bdVisible) {
	glColor4d(vi->borderColor.R, vi->borderColor.G,
		  vi->borderColor.B, vi->borderColor.A);
	glLineWidth(2);
	glBegin(GL_LINE_STRIP);
	glVertex3d(vi->bdxLeft, vi->bdyBottom,-0.001);
	glVertex3d(vi->bdxRight, vi->bdyBottom,-0.001);
	glVertex3d(vi->bdxRight, vi->bdyTop,-0.001);
	glVertex3d(vi->bdxLeft, vi->bdyTop,-0.001);
	glVertex3d(vi->bdxLeft, vi->bdyBottom,-0.001);
	glEnd();
	glLineWidth(1);
    }
}

void drawCircle(double x, double y, double radius, double zdepth) {
    if (radius < 0.3)
	radius = 0.4;
    glBegin(GL_POLYGON);
    for (int i = 0; i < 360; i += 36) {
	const double degInRad = i * DEG2RAD;
	glVertex3d(x + cos(degInRad) * radius, y + sin(degInRad) * radius,
		   zdepth + view->Topview->global_z);
    }

    glEnd();
}

drawfunc_t OpFns[] = {
  [xop_ellipse] = DrawEllipse,
  [xop_polygon] = DrawPolygon,
  [xop_bezier] = DrawBeziers,
  [xop_polyline] = DrawPolyline,
  [xop_text] = EmbedText,
  [xop_fill_color] = SetFillColor,
  [xop_pen_color] = SetPenColor,
  [xop_font] = SetFont,
  [xop_style] = NULL,
  [xop_image] = InsertImage,
  [xop_grad_color] = NULL,
  [xop_fontchar] = NULL,
};

void draw_selpoly(glCompPoly_t *selPoly) {
    glColor4f(1,0,0,1);
    glBegin(GL_LINE_STRIP);
    for (size_t i = 0; i < LIST_SIZE(selPoly); ++i) {
	const glCompPoint pt = LIST_GET(selPoly, i);
	glVertex3f(pt.x, pt.y, pt.z);
    }
    glEnd();
    if (!LIST_IS_EMPTY(selPoly)) {
        const glCompPoint last = *LIST_BACK(selPoly);
        glBegin(GL_LINE_STRIP);
	glVertex3f(last.x, last.y, last.z);
	glVertex3f(view->mouse.GLpos.x,view->mouse.GLpos.y,0);
	glEnd();
    }
}