//gcc -Wall annotator.c -o annotator `pkg-config --cflags --libs gtk+-3.0` `pkg-config --cflags --libs evince-view-3.0`
//Tested on debian 3.16.0 and GTK3.14.5
//      annotator.c
//
//      Copyright 2019 Richard Shann
//
//      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 3 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 Street, Fifth Floor, Boston,
//      MA 02110-1301, USA.
#include <stdlib.h>
#include <math.h>
#include <string.h>
#include<gtk/gtk.h>
#ifdef USE_ATRIL
#include <atril-view.h>
#else
#include <evince-view.h>
#endif

#define SPOT_SIZE (10) //size of spot for picking out an annotation
typedef struct Location {
     gint  adj;
     gint x, y;
} Location;
typedef struct Annotation {
     gchar *annotation;
     gint page;
     gint x, y;
     double r,g,b,a;
     gchar *font;
} Annotation;



static const gchar *music_home;//the directory where your scores are stored
static GtkWidget *score_window;//the window containing the two halves of the score
static GtkWidget *navigation_window = NULL;//floating window for navigation
static GList *repeat_locations = NULL;// a list of locations for use when a repeat starts in the middle/lower half of a page
static GList *annotations = NULL;// a list of annotations to be displayed on the score
static GtkWidget *view;//the EvView* that shows the pages
static GtkWidget *eventbox;
static gchar *fontdesc=NULL;//current default font description string
static gint num_pages;
static gint current_page; // from 0 - 
static gboolean odd_left = TRUE; //if odd nubered pages are on left
static  gint x=0;//Window size and position on screen: 0 0 is top left corner of screen
static  gint y=0;
static  gint width=0;
static  gint height=0;
static gdouble aspect_ratio=1.414; //A4 page size default
static  EvDocumentModel *model;

static void next_page (void);//turn to the next page
static void previous_page (void);//turn back one page
static void goto_page (gint page);//page number starting at 1

static gchar *markings_file = NULL;//full path to file for storing repeat marks and annotations for currently loaded score
static gboolean markings_unsaved = FALSE; //TRUE when user has created or deleted markings in the current score 
static gint page_on = 'c', page_back = 'a', skip_page = 'b';
static guint64 last_pedal_time = 0;

static gchar *help_text =
"The music annotator allows hands-free turning of pages as you play from a musical score."
"\nand adding annotations to be picked up later by Denemo - anything from reminder accidentals"
" to the spectacles O^O that warn of a tricky passage to take special care with."
" The screen is devoted to two pages with either the odd or even pages on the left."
"\nControl of page turning is via foot pedals which send key press signals just like those of a normal keyboard."
" The right pedal goes on and the left goes back "
" The center pedal can be customised to do various tasks"
"\nTo mark up the score for reminders or proof-reading right click with the mouse at the point where you want the annotation to be placed"
" and choose \"Annotate here\" from the menu. You can drag an annotation if it is misplaced."
"\nThe menu also lets you delete an annotation, navigate the score etc."
"\n Currently Keypresses '%c' to go one page on, '%c' to go back for a repeat and '%c' to skip forward."
"\nTo change the defaults you can pass values on the command line - type pageturner --help to see the command line usage."
;

static void navigate (void);

static void show_help (void)
{
   GtkWidget *dialog = gtk_message_dialog_new (GTK_WINDOW (gtk_window_new(GTK_WINDOW_TOPLEVEL)), (GtkDialogFlags) (GTK_DIALOG_DESTROY_WITH_PARENT), GTK_MESSAGE_INFO, GTK_BUTTONS_OK, 
   help_text,
   page_on, page_back, skip_page);
   gtk_widget_show_all (dialog);
   g_signal_connect (dialog, "response", G_CALLBACK (gtk_widget_destroy), NULL);
}

static guint64 elapsed_time ()
{
   gint64 thistime = g_get_monotonic_time ();
   guint64 elapsed = 
   (thistime - last_pedal_time) / 1000; //in milliseconds
   last_pedal_time = g_get_monotonic_time ();
   return elapsed;
}

static void free_annotation (Annotation *a)
{
   g_free (a->annotation);
   g_free (a->font);
   g_free (a);
}
//load repeat marks and annotations from the file associated with the opened pdf score
static void load_markings (gchar *pdfname)
{
   if (markings_file) 
      g_free (markings_file);
   markings_file = g_strdup_printf ("%s%s", pdfname, ".marks");
   FILE *fp = fopen (markings_file, "r");
   if (fp)
      {
         gint window_width, window_height;
         if (2==fscanf (fp, "%d%d", &window_width, &window_height))
            {
               if ((width != window_width) || (height != window_height))
                  g_warning ("Height and Width of markings file does not match current window - expect misplaced marks %d %d %d %d\n", width, height, window_width, window_height);
               gint page, x, y;  
               gchar text1[100], text2[100];
               *text1 = *text2 = 0;
               double r,g,b,a;   
               while ( 7 == fscanf (fp, "%d%d%d%lf%lf%lf%lf\n", &page, &x, &y, &r, &g, &b, &a))
                                 {
                                    Annotation *ann = (Annotation*)g_malloc (sizeof (Annotation));
                                    ann->x = x;
                                    ann->y = y;
                              
                                    ann->page = page;
                                    ann->r = r;
                                    ann->g = g;
                                    ann->b = b;
                                    ann->a = a;
                                    if (fgets (text1, 100, fp))
                                       ann->font = g_strdup (text1);
                                    else
                                       ann->font = g_strdup ("Times 12\n");  
                                    
                                    if (fgets (text2, 100, fp))
                                       ann->annotation = g_strdup (text2);
                                    else
                                       ann->annotation = g_strdup ("???\n"); 
                                    *(ann->font + strlen (ann->font) - 1) = 0;   
                                    *(ann->annotation + strlen (ann->annotation) - 1) = 0;   
                                          
                                    annotations = g_list_append (annotations, ann);
                                 } 
            }
         else  g_warning ("Corrupt markings file");
        fclose (fp);
      }
   markings_unsaved = FALSE;
}
static void
load_score (gchar *pdfname, GError ** err)
{
  GFile *file;
  file = g_file_new_for_commandline_arg (pdfname);
  gchar *uri = g_file_get_uri (file);
  EvDocument *doc = ev_document_factory_get_document (uri, err);
  if (*err)
    {
      g_warning ("Trying to read the pdf file %s gave an error: %s", uri, (*err)->message);
      gtk_widget_queue_draw (view);
    }
  else
   {
     if (model == NULL)
       {
         model = ev_document_model_new_with_document (doc);
         ev_view_set_model ((EvView *) view, model);
      }
     else
      {
         ev_document_model_set_document (model, doc);
       }
G_GNUC_BEGIN_IGNORE_DEPRECATIONS    
      ev_document_model_set_dual_page (model, FALSE);
G_GNUC_END_IGNORE_DEPRECATIONS   
      ev_document_model_set_page (model, 0);
      for (num_pages=1;;num_pages++)
         {
            if (!ev_view_next_page ((EvView*)view))
               break;
         }
      g_print ("Number of pages %d\n", num_pages);
G_GNUC_BEGIN_IGNORE_DEPRECATIONS    
      ev_document_model_set_dual_page (model, TRUE);
G_GNUC_END_IGNORE_DEPRECATIONS   
      ev_document_model_set_page (model, 0);
      ev_document_model_set_dual_page_odd_pages_left (model, odd_left);
      current_page = odd_left?0:-1;  g_print ("current page  %d \n", current_page);
       
      g_list_free_full (repeat_locations, g_free);
      repeat_locations = NULL;
      g_list_free_full (annotations, (GDestroyNotify)free_annotation);
      annotations = NULL;
      load_markings (pdfname);
      goto_page (1);
      if (navigation_window) 
         {
            gtk_widget_destroy (navigation_window);
            navigation_window = NULL;
            navigate ();
         }
   }
  return;
}

static void set_page (gint num)
{
   if ((num >= num_pages) || (num <0))
      {  static gboolean once = FALSE;
         if (once)
            {
               if(num>0)
                  goto_page (1);
               else
                  goto_page (num_pages - 1);
               once = FALSE;
            }
         else
            {
               g_warning ("Attempt to go off page %d\n", num);// two presses of forward wraps round
               once = TRUE;
            }
         return;
      }

  ev_document_model_set_page (model, num);
  current_page = num; 
  if (current_page == 0)
   current_page = odd_left?0:-1;
  g_print ("current page  %d (set page) \n", current_page);
  gtk_widget_queue_draw (view);
}
static void next_page (void)
{
   set_page (current_page + 2);
}


static void previous_page (void)
{
   if (current_page>1)
      set_page (current_page - 2);
   else
     set_page (0);
}

static void do_skip (void)
{

         g_warning ("Nothing implemented");
      
}
static void goto_page (gint page)
{
   ev_document_model_set_page (model, page - 1);
   current_page = page - 1; 
   if (current_page == 0)
      current_page = odd_left?0:-1;
   g_print ("current page  %d (set page) \n", current_page);
}
static void change_page (GtkSpinButton * widget)
{
   goto_page ((gint)gtk_spin_button_get_value (widget));
}

static gboolean keypress (GtkWidget *eventbox, GdkEventKey * event)
{
  guint keyval = event->keyval; 
  
 if (elapsed_time()>100)
      {
      if (keyval==page_on)
       {
         next_page();
       }

      if (keyval==skip_page)
       {
         do_skip ();
       }
      if (keyval==page_back)
       {
         previous_page();
       }
      }
 
  return FALSE;
}

static gboolean choose (gchar *filename)
{
   GtkWidget *top_window=gtk_window_new(GTK_WINDOW_TOPLEVEL);

   GtkWidget *chooser = gtk_file_chooser_dialog_new ("Choose Score",
                        GTK_WINDOW (top_window),
                        GTK_FILE_CHOOSER_ACTION_OPEN,
                        "Ok", GTK_RESPONSE_ACCEPT,
                         NULL);

   GtkFileFilter *filter = gtk_file_filter_new ();
   gtk_file_filter_set_name (filter, "PDF files");
   gtk_file_filter_add_pattern (filter, "*.pdf");
   gtk_file_filter_add_pattern (filter, "*.PDF");
   gtk_file_chooser_add_filter (GTK_FILE_CHOOSER (chooser), filter);

   if (filename && g_file_test(filename, G_FILE_TEST_IS_DIR))
    gtk_file_chooser_set_current_folder (GTK_FILE_CHOOSER (chooser), filename);
   if (gtk_dialog_run (GTK_DIALOG (chooser)) == GTK_RESPONSE_ACCEPT)
       {
         gchar *filename = gtk_file_chooser_get_filename (GTK_FILE_CHOOSER (chooser));
         GError *err = NULL;
         load_score (filename, &err);
      }
   gtk_widget_destroy (chooser);
  return FALSE; //remove this callback
}

static void back_to_main_window ()
{
   gtk_widget_grab_focus (score_window);
   gtk_window_present (GTK_WINDOW (score_window)); 
}

static void navigate (void)
{
  
   if (navigation_window) gtk_widget_destroy (navigation_window);

   navigation_window = gtk_window_new (GTK_WINDOW_TOPLEVEL);
   g_signal_connect (navigation_window, "delete-event", G_CALLBACK(gtk_widget_hide), NULL);
   GtkWidget *label = gtk_label_new ("Set Page Number:");
   GtkWidget *box = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0);
   gtk_container_add (GTK_CONTAINER (navigation_window), box);
   gtk_box_pack_start (GTK_BOX (box), label, FALSE, TRUE, 0);
   GtkWidget *spinner_adj = (GtkWidget *) gtk_adjustment_new (1.0, 1.0, num_pages, 1.0, 1.0, 1.0);
   GtkWidget *spinner = (GtkWidget *) gtk_spin_button_new (GTK_ADJUSTMENT(spinner_adj), 100.0, 0);
   gtk_box_pack_start (GTK_BOX (box), spinner, FALSE, TRUE, 0);
   g_signal_connect (G_OBJECT (spinner), "value-changed", G_CALLBACK (change_page), NULL);
   g_signal_connect_after (G_OBJECT (spinner),  "value-changed", G_CALLBACK (back_to_main_window), NULL);

   gtk_widget_show_all (navigation_window);
}

static void odd_even (void)
{
   odd_left = !odd_left;
   ev_document_model_set_dual_page_odd_pages_left (model, odd_left);
   goto_page (1);
   gtk_widget_queue_draw (view);
}

// text and font must be malloc'd memory so the annotation can be freed
static Annotation *create_annotation (gchar *text, gint page, gdouble x, gdouble y, gchar *font, GdkRGBA *color)
{
    Annotation *ann;
    markings_unsaved = TRUE;
    ann = g_malloc (sizeof (Annotation));
    if (x>width/2)
      {
         x -= width/2;
         page++;
      }
    ann->annotation = text;
    ann->page = page;
    ann->x = x;
    ann->y = y;
    ann->r = color->red;
    ann->g = color->green;
    ann->b = color->blue;
    ann->a = color->alpha;
    ann->font = font;
    return ann;
}

static void delete_annotation (GList *annlink)
{
   
             markings_unsaved = TRUE;
             free_annotation (annlink->data);
             annotations = g_list_delete_link (annotations, annlink);
             gtk_widget_queue_draw (view);
}

static void font_chosen (GtkWidget *fontchooser)
{
   fontdesc = gtk_font_chooser_get_font (GTK_FONT_CHOOSER(fontchooser));
}

static GdkRGBA colordesc = {1.0,0.0,0.0,1.0};
#if 1 //!((GTK_MAJOR_VERSION>=3) && (GTK_MINOR_VERSION>=4)) bizarrely gtk_color_button_get_rgba is declared deprecated but gtk_color_chooser_get_color is not available.
static void color_chosen (GtkWidget *colorchooser)
   {
   G_GNUC_BEGIN_IGNORE_DEPRECATIONS    
      gtk_color_button_get_rgba (GTK_COLOR_BUTTON(colorchooser), &colordesc);
   G_GNUC_END_IGNORE_DEPRECATIONS
   }                    
#else
static void color_chosen (GtkWidget *colorchooser)
   {
      gtk_color_chooser_get_color (GTK_COLOR_CHOOSER(colorchooser), &colordesc);
   }
#endif

static void insert_button_text (GtkWidget *button, GtkWidget *entry)
{
    gchar *text = g_strdup_printf ("%s%s", gtk_entry_get_text (GTK_ENTRY (entry)), gtk_button_get_label(GTK_BUTTON(button)));
    gtk_entry_set_text (GTK_ENTRY (entry), text);
    g_free (text);
}

static void create_button (GtkWidget *hbox, GtkWidget *entry, gchar *text)
{
  GtkWidget *widget = gtk_button_new_with_label (text);
  g_signal_connect (G_OBJECT (widget), "clicked", G_CALLBACK (insert_button_text), entry);
  gtk_box_pack_start (GTK_BOX (hbox), widget, FALSE, FALSE,2); 

}
Annotation *get_annotation_from_user (gint page, gint x, gint y)
{
  GtkWidget *dialog;
  GtkWidget *entry;
  GtkWidget *label;
  gchar *entry_string = NULL;
  entry = gtk_entry_new ();

  dialog = gtk_dialog_new_with_buttons ("Annotation", GTK_WINDOW (gtk_window_new(GTK_WINDOW_TOPLEVEL)), (GtkDialogFlags) (GTK_DIALOG_DESTROY_WITH_PARENT), "OK", GTK_RESPONSE_ACCEPT, "Cancel", GTK_RESPONSE_REJECT, NULL);
  label = gtk_label_new ("Give annotation");
  GtkWidget *content_area = gtk_dialog_get_content_area (GTK_DIALOG (dialog));
  gtk_container_add (GTK_CONTAINER (content_area), label);
  GtkWidget *widget = gtk_font_button_new_with_font (fontdesc?fontdesc:"Sans 16");
  g_signal_connect (G_OBJECT (widget), "font-set", G_CALLBACK (font_chosen), NULL);
  gtk_container_add (GTK_CONTAINER (content_area), widget);
  widget = gtk_color_button_new ();
  G_GNUC_BEGIN_IGNORE_DEPRECATIONS
 gtk_color_button_set_rgba (GTK_COLOR_BUTTON(widget), &colordesc); 
 G_GNUC_END_IGNORE_DEPRECATIONS

  g_signal_connect (G_OBJECT (widget), "color-set", G_CALLBACK (color_chosen), NULL);
  gtk_container_add (GTK_CONTAINER (content_area), widget); 
  GtkWidget *hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0);
  gtk_container_add (GTK_CONTAINER (content_area), hbox); 
  
  create_button (hbox, entry, "O^O");
  create_button (hbox, entry, "♯");
  create_button (hbox, entry, "♭");
  create_button (hbox, entry, "♮");
  create_button (hbox, entry, "𝄪");
  create_button (hbox, entry, "𝄫");
  create_button (hbox, entry, "FIX -->");
  create_button (hbox, entry, "<---FIX");
   
    
  gtk_entry_set_text (GTK_ENTRY (entry), "");
  gtk_container_add (GTK_CONTAINER (content_area), entry);

  gtk_entry_set_activates_default (GTK_ENTRY (entry), TRUE);
  gtk_dialog_set_default_response (GTK_DIALOG (dialog), GTK_RESPONSE_ACCEPT);
  gtk_widget_show_all (dialog);

  if (gtk_dialog_run (GTK_DIALOG (dialog)) == GTK_RESPONSE_ACCEPT)
        {
          gchar *string = NULL;
          
          if (GTK_DIALOG (dialog))
            {
               entry_string = (gchar *) gtk_entry_get_text (GTK_ENTRY (entry));
               string = g_strdup (entry_string);
               gtk_widget_destroy (dialog);
               Annotation *ann = create_annotation (string, page, x, y, g_strdup (fontdesc?fontdesc:"Sans 16"), &colordesc);
               return ann;
           }
       }
  else
   {
     gtk_widget_destroy (dialog);
   }
   return NULL;
}


  
static void mark_annotation (Annotation *p)
{
   Annotation *ann = get_annotation_from_user (p->page, p->x, p->y);
   if (ann)
      {
         annotations = g_list_append (annotations, ann);
         gtk_widget_queue_draw (view);
      }
}

static void mark_spot (Annotation *p)
{
   GdkRGBA color = { 0.98, 0.91, 0.3, 0.8 };
   Annotation *ann = create_annotation  (g_strdup("●"), p->page, p->x, p->y, g_strdup("denemo medium 40"), &color);
   if (ann)
      {
         annotations = g_list_append (annotations, ann);
         gtk_widget_queue_draw (view);
      }
}

static void save_annotations (void)
{
  if (markings_file)
      {
         FILE *fp = fopen (markings_file, "w");
         if (fp)
            {
               GList *g;
               fprintf (fp, "%d %d\n", width/2, height); g_print ("Saved %d %d\n", width/2, height);
             
               for (g=annotations;g;g=g->next)
                  {
                   Annotation *ann = (Annotation *)g->data;
                   fprintf (fp, "%d %d %d %f %f %f %f\n%s\n%s\n", ann->page, (int)ann->x, (int)ann->y, ann->r, ann->g, ann->b, ann->a, ann->font, ann->annotation);
                  }  
               fclose (fp);
            }
         else
            g_warning ("Could not write %s for markings\n", markings_file);
      }
   else
      g_warning ("No file for markings");
}

   
static GList *nearby_annotation (gint page, gint x, gint y)
{
   GList *g;
   for (g = annotations; g; g=g->next)
      {
        Annotation *ann = g->data;
         if ((ann->page == current_page) && abs(ann->x-x+15)<SPOT_SIZE && abs(ann->y-y+15)<SPOT_SIZE)
            {
              return g;
            }
         else 
           if ((ann->page == current_page + 1) && abs(width/2 + ann->x-x+15)<SPOT_SIZE && abs(ann->y-y+15)<SPOT_SIZE)
            {
              return g;
            }
      }
   return NULL;
}


void
hot_cursor (void)
{
  static GdkCursor *circ = NULL;
  if (!circ)
    circ = gdk_cursor_new_for_display (gdk_display_get_default (), GDK_TARGET);
  gdk_window_set_cursor (gtk_widget_get_window (score_window), circ);
}

void
normal_cursor (void)
{
  static GdkCursor *arrowcursor = NULL;
  if (!arrowcursor)
    arrowcursor = gdk_cursor_new_for_display (gdk_display_get_default (), GDK_LEFT_PTR);
  gdk_window_set_cursor (gtk_widget_get_window (score_window), arrowcursor);
}


static GList *dragging_annlink = NULL;
static gboolean button_press (GtkWidget * view, GdkEventButton * event)
{
  if (event->button == 1)
   { 
      Annotation current_position;//just as a page, x, y , not a real annotation
      current_position.page = current_page;
      current_position.x = (int)event->x;
      current_position.y = (int)event->y;
      dragging_annlink = nearby_annotation (current_position.page, current_position.x, current_position.y);
    //  if (dragging_annlink)
     //    hot_cursor();
   }
   return TRUE;
  return FALSE;                 //propagate further 
}

static gboolean motion_notify (GtkWidget * view, GdkEventMotion * event)
{
   if (dragging_annlink)
      { 
         Annotation *ann = dragging_annlink->data;
         if (ann->page == current_page)
           {
               markings_unsaved = TRUE;
               ann->x = event->x, ann->y = event->y;
               gtk_widget_queue_draw (view);
               return TRUE;
            }
         else
         if (ann->page == current_page +1)
           {
               markings_unsaved = TRUE;
               ann->x = event->x - width/2, ann->y = event->y;
               gtk_widget_queue_draw (view);
               return TRUE;
            }         
         
         
      }
      Annotation current_position;//just as a page, x, y , not a real annotation
      current_position.page = current_page;
      current_position.x = (int)event->x;
      current_position.y = (int)event->y;
      if (nearby_annotation (current_position.page, current_position.x, current_position.y))
         hot_cursor ();
      else
         normal_cursor ();
 
   return FALSE;                 //propagate further
}

static gboolean button_release (GtkWidget * view, GdkEventButton * event)
{
  if (dragging_annlink)
      {
      normal_cursor ();
      dragging_annlink = NULL;
      return TRUE;
      }
  if (event->button != 1)
   { 
      static Annotation current_position;//just as a page, x, y , not a real annotation
      current_position.page = current_page;
      current_position.x = (int)event->x;
      current_position.y = (int)event->y;
      GtkWidget *menu = gtk_menu_new ();
      GtkWidget *item;



      item = gtk_menu_item_new_with_label ("Annotate here");
      gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
      g_signal_connect_swapped (G_OBJECT (item), "activate", G_CALLBACK (mark_annotation), &current_position);
      item = gtk_menu_item_new_with_label ("Spot here");
      gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
      g_signal_connect_swapped (G_OBJECT (item), "activate", G_CALLBACK (mark_spot), &current_position);
      
      
      
      GList *annlink = nearby_annotation (current_position.page, current_position.x, current_position.y);
      item = gtk_menu_item_new_with_label ("Delete this annotation");
      gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
      g_signal_connect_swapped (G_OBJECT (item), "activate", G_CALLBACK (delete_annotation), annlink);
      gtk_widget_set_sensitive (item,(annlink != NULL));
      
      item = gtk_menu_item_new_with_label ("Save annotations");
      gtk_widget_set_sensitive (item,markings_unsaved);
      gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
      g_signal_connect (G_OBJECT (item), "activate", G_CALLBACK (save_annotations), NULL);
        
      item = gtk_menu_item_new_with_label ("Navigate");
      gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
      g_signal_connect_swapped (G_OBJECT (item), "activate", G_CALLBACK (navigate), NULL);

      item = gtk_menu_item_new_with_label ("Choose score");
      gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
      g_signal_connect_swapped (G_OBJECT (item), "activate", G_CALLBACK (choose), NULL);
      
      item = gtk_menu_item_new_with_label ("Switch Odd/Even pages on left");
      gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
      g_signal_connect_swapped (G_OBJECT (item), "activate", G_CALLBACK (odd_even), NULL);
          
       
      item = gtk_menu_item_new_with_label ("Help");
      gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
      g_signal_connect_swapped (G_OBJECT (item), "activate", G_CALLBACK (show_help), NULL); 
      item = gtk_menu_item_new_with_label ("Quit");
      gtk_menu_shell_append (GTK_MENU_SHELL (menu), item);
      g_signal_connect_swapped (G_OBJECT (item), "activate", G_CALLBACK (gtk_main_quit), NULL);     

      gtk_widget_show_all (menu);
#if ((GTK_MAJOR_VERSION==3) && (GTK_MINOR_VERSION>=22))
      gtk_menu_popup_at_pointer (GTK_MENU (menu), NULL);
#else
// FIXME something for gtk2
#endif   
      return TRUE;
   }
 return FALSE;
}


static void draw_text (cairo_t * cr, const char *font, const char *text, double x, double y, gboolean invert)
{
  //y -= size;
  //size *= 0.75;
  PangoLayout *layout;
  PangoFontDescription *desc;
  /* Create a PangoLayout, set the font and text */
  layout = pango_cairo_create_layout (cr);

  pango_layout_set_text (layout, text, -1);
  desc = pango_font_description_from_string (font);
 // pango_font_description_set_size (desc, size * PANGO_SCALE);
  pango_layout_set_font_description (layout, desc);
  pango_font_description_free (desc);
  pango_cairo_update_layout (cr, layout);


  cairo_move_to (cr, x, y);
  if (invert)
    cairo_scale (cr, 1, -1);
  pango_cairo_show_layout (cr, layout);
  /* free the layout object */
  g_object_unref (layout);
}



      
static gboolean overdraw (GtkWidget* view, cairo_t * cr)
{
   GList *g;
   gint pnum = current_page;
   for (g = annotations; g; g=g->next)
      {
         Annotation *ann = (Annotation*)g->data;
         gdouble x = ann->x, y = ann->y; 
         //g_print ("annotation %s page %d for current page %d?  x %d x+ halfwidth %d\n", ann->annotation, ann->page, pnum, (int)x, (int)(x+width/2));
         if (ann->page == pnum)
            {

               cairo_set_source_rgba (cr, ann->r, ann->g, ann->b, ann->a);
              
                  draw_text (cr, ann->font, ann->annotation, x, y, FALSE);
                  
            }
         else
         if (ann->page == pnum + 1)
            {
               cairo_set_source_rgba (cr, ann->r, ann->g, ann->b, ann->a);
               draw_text (cr, ann->font, ann->annotation, x + width/2, y, FALSE);
            }
      }
  return FALSE;
}


int main(int argc, char **argv)
 {
   gtk_init(&argc, &argv);
   GdkRectangle r;
#if ((GTK_MAJOR_VERSION==3) && (GTK_MINOR_VERSION>=22))
   gdk_monitor_get_workarea (gdk_display_get_primary_monitor (gdk_display_get_default ()), &r);
#else
// FIXME something for gtk2
#endif   
   width = r.width;
   height = 0;
 
   if (argc>1 && (1 != sscanf (argv[1], "%d", (int*)&page_on)))
    goto error;      
   if (argc>2 && (1 != sscanf (argv[2], "%d", (int*)&page_back)))
    goto error;      
   if (argc>3 && (1 != sscanf (argv[3], "%d", (int*)&skip_page)))
    goto error;      

      
   if (argc>4 && (1 != sscanf (argv[4], "%lf", &aspect_ratio)))
    goto error;
   if (argc>5 && (1 != sscanf (argv[5], "%d", &width)))
    goto error;
   if (argc>6 && (1 != sscanf (argv[6], "%d", &height)))
    goto error;
   if (height == 0)
         {
            if (aspect_ratio<0.001)
               aspect_ratio = 1.414;
            height = width * aspect_ratio;
            if (height > r.height)
               height = r.height;
            width = height/aspect_ratio;   
            x = (r.width-width)/2;
         }
   width *= 2; //duplex view see set_dual above
   g_print ("Using height %d width %d, aspect ratio %f at %d horizontally\n", height, width, aspect_ratio, x);
   music_home = g_get_home_dir();
   ev_init ();
   score_window=gtk_window_new(GTK_WINDOW_TOPLEVEL);
   gtk_window_set_decorated (GTK_WINDOW (score_window), FALSE);
   g_signal_connect (score_window, "destroy", G_CALLBACK(gtk_main_quit), NULL);

   gtk_window_move (GTK_WINDOW (score_window), x, y);
   gtk_window_set_default_size (GTK_WINDOW (score_window), width, height);
   GtkWidget *main_hbox = gtk_box_new (GTK_ORIENTATION_HORIZONTAL, 0);
   gtk_container_add (GTK_CONTAINER(score_window), main_hbox);
   
   eventbox = gtk_event_box_new ();
   
   gtk_widget_add_events (eventbox, (GDK_BUTTON_RELEASE_MASK | GDK_BUTTON_PRESS_MASK | GDK_KEY_PRESS_MASK | GDK_KEY_RELEASE_MASK ));
   gtk_box_pack_start (GTK_BOX(main_hbox), eventbox, TRUE, TRUE, 0);
   
   GtkWidget *scroll = gtk_scrolled_window_new (NULL, NULL);
   gtk_container_add (GTK_CONTAINER(eventbox), scroll); 
   g_signal_connect (G_OBJECT(eventbox), "key-press-event", G_CALLBACK (keypress), NULL);
   view = (GtkWidget *) ev_view_new ();
   g_signal_connect (G_OBJECT(view), "button-release-event", G_CALLBACK (button_release), NULL);
   g_signal_connect (G_OBJECT(view), "button-press-event", G_CALLBACK (button_press), NULL);

   g_signal_connect (G_OBJECT (view), "motion_notify_event", G_CALLBACK (motion_notify), NULL);

   g_signal_connect_after (G_OBJECT (view), "draw", G_CALLBACK (overdraw), NULL);
   gtk_container_add (GTK_CONTAINER (scroll), view);

   gtk_widget_show_all (score_window);
   gtk_widget_hide (gtk_scrolled_window_get_vscrollbar (GTK_SCROLLED_WINDOW(scroll)));
  
   if (argc==1)
      show_help();
   g_idle_add ((GSourceFunc) choose, (gpointer) music_home);
   gtk_main();

   return 0;  
   error:
        g_print ("Usage: pageswitcher [page onward, default %d (ie '%c')] [lh page back, default  %d (ie '%c')]  [rh page forward, default  %d (ie '%c')]  [aspect ratio, default 1.414, ie A4] [width in pixels, default maximum][height in pixels - overrides monitor size and aspect ratio]\n",
               page_on, page_on, page_back, page_back, skip_page, skip_page);
         return -1;
 }