#include "draw.h"
#include "level.h"
#include "geometry.h"
#include <math.h>
#include <gtk/gtk.h>
#include <cairo/cairo.h>


static double scale = 100.0;
static double xTranslate = 0.0, yTranslate = 0.0;


static void drawGrid(cairo_t *cr, const RECTANGLE *rect) {
  double depth = log10(scale)-0.75;
  double depth2 = floor(depth);
  double step = pow(0.1, depth2);
  double x;
  int i;
  
  cairo_set_source_rgb(cr, 0.2*(depth-depth2), 0.2*(depth-depth2), 0.2*(depth-depth2));
  
  for(i = 0; i < 3; i++) {
    for(x = rect->x - fmod(rect->x, step); x <= rect->x+rect->width; x+=step) {
      cairo_move_to(cr, x, rect->y);
      cairo_line_to(cr, x, rect->y+rect->height);
      
      cairo_stroke(cr);
    }
    
    for(x = rect->y - fmod(rect->y, step); x <= rect->y+rect->height; x+=step) {
      cairo_move_to(cr, rect->x, x);
      cairo_line_to(cr, rect->x+rect->width, x);
      
      cairo_stroke(cr);
    }
    
    step *= 10;
    if(i == 0 && 0.2*(depth-depth2+1) < 0.3)
      cairo_set_source_rgb(cr, 0.2*(depth-depth2+1), 0.2*(depth-depth2+1), 0.2*(depth-depth2+1));
    else
      cairo_set_source_rgb(cr, 0.3, 0.3, 0.3);
  }
}

static void room2path(cairo_t *cr, const ROOM *room, const RECTANGLE *rect) {
  int i;
  ROOM room2 = {0, NULL};
  
  // no vertices
  if(room->nVertices == 0) return;
  
  if(rect)
    simplifyPolygon(room, rect, &room2);
  else
    room2 = *room;
  
  if(room2.nVertices == 0) return;
  
  cairo_new_sub_path(cr);
  
  for(i = 0; i < room2.nVertices; i++) {
    cairo_line_to(cr, room2.vertices[i].x, room2.vertices[i].y);
  }
  
  cairo_close_path(cr);
  
  if(rect && room2.vertices)
    free(room2.vertices);
}

gboolean drawTopView(GtkWidget *widget, GdkEventExpose *event, gpointer data) {
  VERTEX vertices[4] = {{-1,-1}, {-1,1}, {1,1}, {1,-1}};
  ROOM room = {sizeof(vertices)/sizeof(vertices[0]), vertices};
  LEVEL lvl = {1, &room};
  cairo_t *cr;
  RECTANGLE rect = {-5, -5, widget->allocation.width+10, widget->allocation.height+10};
  int i;
  
  
  cr = gdk_cairo_create(widget->window);
  
  gdk_cairo_region(cr, event->region);
  cairo_clip(cr);
  
  cairo_translate(cr, getImageWidth()/2-xTranslate, getImageHeight()/2-yTranslate);
  cairo_scale(cr, scale, scale);
  
  cairo_device_to_user(cr, &rect.x, &rect.y);
  cairo_device_to_user_distance(cr, &rect.width, &rect.height);
  
  cairo_set_line_width(cr, 1.0/scale);
  cairo_set_line_join(cr, CAIRO_LINE_JOIN_MITER);
  
  drawGrid(cr, &rect);
  
  for(i = 0; i < lvl.nRooms; i++)
    room2path(cr, &lvl.rooms[i], &rect);
  
  cairo_set_source_rgba(cr, 0.0, 0.7, 1.0, 0.3);
  cairo_fill_preserve(cr);
  
  cairo_set_source_rgba(cr, 0.0, 0.7, 1.0, 0.7);
  cairo_stroke(cr);
  
  cairo_destroy (cr);
  
  return FALSE;
}

double getScale() {
  return scale;
}

void setScale(double s) {
  scale = s;
}

double getImageWidth() {
  return 5*scale;
}

double getImageHeight() {
  return 5*scale;
}

double getXTranslate() {
  return xTranslate;
}

void setXTranslate(double x) {
  xTranslate = x;
}

double getYTranslate() {
  return yTranslate;
}

void setYTranslate(double y) {
  yTranslate = y;
}