Some spelling fixes in a comment

[andy/viking.git] / src / bingmapsource.c

/* -*- Mode: C; indent-tabs-mode: t; c-basic-offset: 4; tab-width: 4 -*- */
/*
 * viking
 * Copyright (C) 2011, Guilhem Bonnefille <guilhem.bonnefille@gmail.com>
 * 
 * viking 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 2 of the License, or
 * (at your option) any later version.
 * 
 * viking 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, see <http://www.gnu.org/licenses/>.
 */
 
 /**
  * SECTION:bingmapsource
  * @short_description: the class for Bing Maps
  * 
  * The #BingMapSource class handles Bing map source.
  * 
  * License and term of use are available here:
  * http://wiki.openstreetmap.org/wiki/File:Bing_license.pdf
  * 
  * Technical details are available here:
  * http://msdn.microsoft.com/en-us/library/dd877180.aspx
  */
  
#ifdef HAVE_CONFIG_H
#include "config.h"
#endif

#ifdef HAVE_MATH_H
#include <math.h>
#endif

#ifdef HAVE_STDLIB_H
#include <stdlib.h>
#endif
#include <glib.h>
#include <glib/gstdio.h>
#include <glib/gi18n.h>
#include <gdk-pixbuf/gdk-pixdata.h>
#include "globals.h"
#include "bingmapsource.h"
#include "maputils.h"
#include "bbox.h"
#include "background.h"
#include "icons/icons.h"

/* Format for URL */
#define URL_ATTR_FMT "http://dev.virtualearth.net/REST/v1/Imagery/Metadata/Aerial/0,0?zl=1&mapVersion=v1&key=%s&include=ImageryProviders&output=xml"

static gchar *bget_uri ( VikMapSourceDefault *self, MapCoord *src );
static gchar *bget_hostname ( VikMapSourceDefault *self );
static void _get_copyright (VikMapSource * self, LatLonBBox bbox, gdouble zoom, void (*fct)(VikViewport*,const gchar*), void *data);
static const GdkPixbuf *_get_logo ( VikMapSource *self );
static int _load_attributions ( BingMapSource *self );
static void _async_load_attributions ( BingMapSource *self );

struct _Attribution
{
	gchar *attribution;
	int minZoom;
	int maxZoom;
	LatLonBBox bounds;
};

typedef struct _BingMapSourcePrivate BingMapSourcePrivate;
struct _BingMapSourcePrivate
{
	gchar *hostname;
	gchar *url;
	gchar *api_key;
	GList *attributions;
	/* Current attribution, when parsing */
	gchar *attribution;
	gboolean loading_attributions;
};

/* The pixbuf to store the logo */
static GdkPixbuf *pixbuf = NULL;

#define BING_MAP_SOURCE_GET_PRIVATE(o)  (G_TYPE_INSTANCE_GET_PRIVATE ((o), BING_TYPE_MAP_SOURCE, BingMapSourcePrivate))

/* properties */
enum
{
	PROP_0,

	PROP_HOSTNAME,
	PROP_URL,
	PROP_API_KEY,
};

G_DEFINE_TYPE (BingMapSource, bing_map_source, VIK_TYPE_SLIPPY_MAP_SOURCE);

static void
bing_map_source_init (BingMapSource *self)
{
	/* initialize the object here */
	BingMapSourcePrivate *priv = BING_MAP_SOURCE_GET_PRIVATE (self);

	priv->hostname = NULL;
	priv->url = NULL;
	priv->api_key = NULL;
	priv->attributions = NULL;
	priv->attribution = NULL;
	priv->loading_attributions = FALSE;
}

static void
bing_map_source_finalize (GObject *object)
{
	BingMapSource *self = BING_MAP_SOURCE (object);
	BingMapSourcePrivate *priv = BING_MAP_SOURCE_GET_PRIVATE (self);

	g_free (priv->hostname);
	priv->hostname = NULL;
	g_free (priv->url);
	priv->url = NULL;
	g_free (priv->api_key);
	priv->api_key = NULL;

	G_OBJECT_CLASS (bing_map_source_parent_class)->finalize (object);
}

static void
_set_property (GObject      *object,
               guint         property_id,
               const GValue *value,
               GParamSpec   *pspec)
{
	BingMapSource *self = BING_MAP_SOURCE (object);
	BingMapSourcePrivate *priv = BING_MAP_SOURCE_GET_PRIVATE (self);

	switch (property_id)
	{
	case PROP_HOSTNAME:
		g_free (priv->hostname);
		priv->hostname = g_value_dup_string (value);
		break;

	case PROP_URL:
		g_free (priv->url);
		priv->url = g_value_dup_string (value);
		break;

	case PROP_API_KEY:
		priv->api_key = g_strdup (g_value_get_string (value));
		break;

	default:
		/* We don't have any other property... */
		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
		break;
	}
}

static void
_get_property (GObject    *object,
               guint       property_id,
               GValue     *value,
               GParamSpec *pspec)
{
	BingMapSource *self = BING_MAP_SOURCE (object);
	BingMapSourcePrivate *priv = BING_MAP_SOURCE_GET_PRIVATE (self);

	switch (property_id)
	{
	case PROP_HOSTNAME:
		g_value_set_string (value, priv->hostname);
		break;

	case PROP_URL:
		g_value_set_string (value, priv->url);
		break;

	case PROP_API_KEY:
		g_value_set_string (value, priv->api_key);
		break;

	default:
		/* We don't have any other property... */
		G_OBJECT_WARN_INVALID_PROPERTY_ID (object, property_id, pspec);
		break;
	}
}


static void
bing_map_source_class_init (BingMapSourceClass *klass)
{
	GObjectClass* object_class = G_OBJECT_CLASS (klass);
	VikMapSourceDefaultClass* grandparent_class = VIK_MAP_SOURCE_DEFAULT_CLASS (klass);
	VikMapSourceClass* base_class = VIK_MAP_SOURCE_CLASS (klass);
	GParamSpec *pspec = NULL;

	/* Overiding methods */
	object_class->set_property = _set_property;
	object_class->get_property = _get_property;
	grandparent_class->get_uri = bget_uri;
	grandparent_class->get_hostname = bget_hostname;
	base_class->get_logo      = _get_logo;
	base_class->get_copyright = _get_copyright;

	pspec = g_param_spec_string ("hostname",
	                             "Hostname",
	                             "The hostname of the map server",
	                             "<no-set>" /* default value */,
	                             G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
	g_object_class_install_property (object_class, PROP_HOSTNAME, pspec);

	pspec = g_param_spec_string ("url",
	                             "URL",
	                             "The template of the tiles' URL",
	                             "<no-set>" /* default value */,
	                             G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
	g_object_class_install_property (object_class, PROP_URL, pspec);

	pspec = g_param_spec_string ("api-key",
                                     "API key",
                                     "The API key to access Bing",
                                     "<no-set>" /* default value */,
                                     G_PARAM_CONSTRUCT_ONLY | G_PARAM_READWRITE);
	g_object_class_install_property (object_class, PROP_API_KEY, pspec);

	g_type_class_add_private (klass, sizeof (BingMapSourcePrivate));
	
	object_class->finalize = bing_map_source_finalize;

	pixbuf = gdk_pixbuf_from_pixdata ( &bing_maps_pixbuf, TRUE, NULL );
}

static gchar *
compute_quad_tree(int zoom, int tilex, int tiley)
{
	/* Picked from http://trac.openstreetmap.org/browser/applications/editors/josm/plugins/slippymap/src/org/openstreetmap/josm/plugins/slippymap/SlippyMapPreferences.java?rev=24486 */
	gchar k[20];
	int ik = 0;
	int i = 0;
	for(i = zoom; i > 0; i--)
	{
		char digit = 48;
		int mask = 1 << (i - 1);
		if ((tilex & mask) != 0) {
			digit += 1;
		}
		if ((tiley & mask) != 0) {
			digit += 2;
		}
		k[ik++] = digit;
	}
	k[ik] = '\0';
	return g_strdup(k);
}

static gchar *
bget_uri( VikMapSourceDefault *self, MapCoord *src )
{
	g_return_val_if_fail (BING_IS_MAP_SOURCE(self), NULL);

	BingMapSourcePrivate *priv = BING_MAP_SOURCE_GET_PRIVATE(self);
	gchar *quadtree = compute_quad_tree (17 - src->scale, src->x, src->y);
	gchar *uri = g_strdup_printf ( priv->url, quadtree );
	g_free (quadtree);
	return uri;
} 

static gchar *
bget_hostname( VikMapSourceDefault *self )
{
	g_return_val_if_fail (BING_IS_MAP_SOURCE(self), NULL);

	BingMapSourcePrivate *priv = BING_MAP_SOURCE_GET_PRIVATE(self);
	return g_strdup( priv->hostname );
}

static const GdkPixbuf *
_get_logo( VikMapSource *self )
{
	return pixbuf;
}

static void
_get_copyright(VikMapSource * self, LatLonBBox bbox, gdouble zoom, void (*fct)(VikViewport*,const gchar*), void *data)
{
	g_return_if_fail (BING_IS_MAP_SOURCE(self));
	g_debug("%s: looking for %g %g %g %g at %g", __FUNCTION__, bbox.south, bbox.north, bbox.east, bbox.west, zoom);

	BingMapSourcePrivate *priv = BING_MAP_SOURCE_GET_PRIVATE(self);

	int level = map_utils_mpp_to_scale (zoom);

	/* Loop over all known attributions */
	GList *attribution = priv->attributions;
	if (attribution == NULL && g_strcmp0 ("<no-set>", priv->api_key)) {
		if ( ! priv->loading_attributions )
			_async_load_attributions (BING_MAP_SOURCE (self));
		else
			// Wait until attributions loaded before processing them
			return;
	}
	while (attribution != NULL) {
		struct _Attribution *current = (struct _Attribution*)attribution->data;
		/* g_debug("%s %g %g %g %g %d %d", __FUNCTION__, current->bounds.south, current->bounds.north, current->bounds.east, current->bounds.west, current->minZoom, current->maxZoom); */
		if (BBOX_INTERSECT(bbox, current->bounds) &&
		    (17 - level) > current->minZoom &&
		    (17 - level) < current->maxZoom) {
			(*fct)(data, current->attribution);
			g_debug("%s: found match %s", __FUNCTION__, current->attribution);
		}
		attribution = attribution->next;
	}
}

/* Called for open tags <foo bar="baz"> */
static void
bstart_element (GMarkupParseContext *context,
                const gchar         *element_name,
                const gchar        **attribute_names,
                const gchar        **attribute_values,
                gpointer             user_data,
                GError             **error)
{
	BingMapSource *self = BING_MAP_SOURCE (user_data);
	BingMapSourcePrivate *priv = BING_MAP_SOURCE_GET_PRIVATE (self);
	const gchar *element = g_markup_parse_context_get_element (context);
	if (strcmp (element, "CoverageArea") == 0) {
		/* New Attribution */
		struct _Attribution *attribution = g_malloc0 (sizeof(struct _Attribution));
		priv->attributions = g_list_append (priv->attributions, attribution);
		attribution->attribution = g_strdup (priv->attribution);
	}
}

/* Called for character data */
/* text is not nul-terminated */
static void
btext (GMarkupParseContext *context,
       const gchar         *text,
       gsize                text_len,  
       gpointer             user_data,
       GError             **error)
{
	BingMapSource *self = BING_MAP_SOURCE (user_data);
	BingMapSourcePrivate *priv = BING_MAP_SOURCE_GET_PRIVATE (self);

	struct _Attribution *attribution = priv->attributions == NULL ? NULL : g_list_last (priv->attributions)->data;
	const gchar *element = g_markup_parse_context_get_element (context);
	gchar *textl = g_strndup (text, text_len);
	const GSList *stack = g_markup_parse_context_get_element_stack (context);
	int len = g_slist_length ((GSList *)stack);

	const gchar *parent = len > 1 ? g_slist_nth_data ((GSList *)stack, 1) : NULL;
	if (strcmp (element, "Attribution") == 0) {
		g_free (priv->attribution);
		priv->attribution = g_strdup (textl);
	}
	else {
		if ( attribution ) {
			if (parent != NULL && strcmp (parent, "CoverageArea") == 0) {
				if (strcmp (element, "ZoomMin") == 0) {
					attribution->minZoom = atoi (textl);
				} else if (strcmp (element, "ZoomMax") == 0) {
					attribution->maxZoom = atoi (textl);
				}
			} else if (parent != NULL && strcmp (parent, "BoundingBox") == 0) {
				if (strcmp (element, "SouthLatitude") == 0) {
					attribution->bounds.south = g_ascii_strtod (textl, NULL);
				} else if (strcmp (element, "WestLongitude") == 0) {
					attribution->bounds.west = g_ascii_strtod (textl, NULL);
				} else if (strcmp (element, "NorthLatitude") == 0) {
					attribution->bounds.north = g_ascii_strtod (textl, NULL);
				} else if (strcmp (element, "EastLongitude") == 0) {
					attribution->bounds.east = g_ascii_strtod (textl, NULL);
				}
			}
		}
	}
	g_free(textl);
}

static gboolean
_parse_file_for_attributions(BingMapSource *self, gchar *filename)
{
	GMarkupParser xml_parser;
	GMarkupParseContext *xml_context = NULL;
	GError *error = NULL;
	BingMapSourcePrivate *priv = BING_MAP_SOURCE_GET_PRIVATE (self);
	g_return_val_if_fail(priv != NULL, FALSE);

	FILE *file = g_fopen (filename, "r");
	if (file == NULL)
		/* TODO emit warning */
		return FALSE;
	
	/* setup context parse (ie callbacks) */
	xml_parser.start_element = &bstart_element;
	xml_parser.end_element = NULL;
	xml_parser.text = &btext;
	xml_parser.passthrough = NULL;
	xml_parser.error = NULL;
	
	xml_context = g_markup_parse_context_new(&xml_parser, 0, self, NULL);

	gchar buff[BUFSIZ];
	size_t nb;
	size_t offset = -1;
	while (xml_context &&
	       (nb = fread (buff, sizeof(gchar), BUFSIZ, file)) > 0)
	{
		if (offset == -1)
			/* first run */
			/* Avoid possible BOM at begining of the file */
			offset = buff[0] == '<' ? 0 : 3;
		else
			/* reset offset */
			offset = 0;
		if (!g_markup_parse_context_parse(xml_context, buff+offset, nb-offset, &error))
		{
			fprintf(stderr, "%s: parsing error: %s.\n",
				__FUNCTION__, error->message);
			g_markup_parse_context_free(xml_context);
			xml_context = NULL;
		}
		g_clear_error (&error);
	}
	/* cleanup */
	if (xml_context &&
	    !g_markup_parse_context_end_parse(xml_context, &error))
		fprintf(stderr, "%s: errors occurred while reading file: %s.\n",
			__FUNCTION__, error->message);
	g_clear_error (&error);
	
	if (xml_context)
		g_markup_parse_context_free(xml_context);
	xml_context = NULL;
	fclose (file);

	if (vik_debug) {
		GList *attribution = priv->attributions;
		while (attribution != NULL) {
			struct _Attribution *aa = (struct _Attribution*)attribution->data;
			g_debug ("Bing Attribution: %s from %d to %d %g %g %g %g", aa->attribution, aa->minZoom, aa->maxZoom, aa->bounds.south, aa->bounds.north, aa->bounds.east, aa->bounds.west);
			attribution = attribution->next;
		}
	}

	return TRUE;
}

static int
_load_attributions ( BingMapSource *self )
{
	int ret = 0;  /* OK */

	BingMapSourcePrivate *priv = BING_MAP_SOURCE_GET_PRIVATE (self);
	priv->loading_attributions = TRUE;
	gchar *uri = g_strdup_printf(URL_ATTR_FMT, priv->api_key);

	gchar *tmpname = a_download_uri_to_tmp_file ( uri, vik_map_source_default_get_download_options(VIK_MAP_SOURCE_DEFAULT(self)) );
	if ( !tmpname ) {
		ret = -1;
		goto done;
	}

	g_debug("%s: %s", __FUNCTION__, tmpname);
	if (!_parse_file_for_attributions(self, tmpname)) {
		ret = -1;
	}

	(void)g_remove(tmpname);
	g_free(tmpname);
done:
	priv->loading_attributions = FALSE;
	g_free(uri);
	return ret;
}

static gboolean
_emit_update ( gpointer data )
{
	//if ( data )
	//	vik_layers_panel_emit_update ( VIK_LAYERS_PANEL (data) );
	return FALSE;
}

static int
_load_attributions_thread ( BingMapSource *self, gpointer threaddata )
{
	_load_attributions ( self );
	int result = a_background_thread_progress ( threaddata, 1.0 );
	if ( result != 0 )
		return -1; /* Abort thread */

	/* Emit update */
	// As we are on a download thread, must the update GUI from the main loop
	// TODO: have reference to the window/viewport/layerspanel to update...
	(void)gdk_threads_add_idle ( _emit_update, NULL );

	return 0;
}

static void
_async_load_attributions ( BingMapSource *self )
{
	a_background_thread ( BACKGROUND_POOL_REMOTE,
	                      /*VIK_GTK_WINDOW_FROM_WIDGET(vp)*/NULL,
	                      _("Bing attribution Loading"),
	                      (vik_thr_func) _load_attributions_thread,
	                      self,
	                      NULL,
	                      NULL,
	                      1 );
     
}

/**
 * bing_map_source_new_with_id:
 * @id: internal identifier.
 * @label: the label to display in map provider selector.
 * @key: the API key to access Bing's services.
 *
 * Constructor for Bing map source.
 *
 * Returns: a newly allocated BingMapSource GObject.
 */
BingMapSource *
bing_map_source_new_with_id (guint16 id, const gchar *label, const gchar *key)
{
	/* initialize settings here */
	return g_object_new(BING_TYPE_MAP_SOURCE,
	                    "id", id,
						"label", label,
						"name", "Bing-Aerial",
						"hostname", "ecn.t2.tiles.virtualearth.net",
						"url", "/tiles/a%s.jpeg?g=587",
						"api-key", key,
						"check-file-server-time", TRUE,
						"zoom-min", 0,
						"zoom-max", 19, // NB: Might be regionally different rather than the same across the world
						"copyright", "© 2011 Microsoft Corporation and/or its suppliers",
						"license", "Microsoft Bing Maps Specific",
						"license-url", "http://www.microsoft.com/maps/assets/docs/terms.aspx",
						NULL);
}