from django.utils.safestring import mark_safe

from django.contrib.gis.geos import fromstr, Point, LineString, LinearRing, Polygon

class GEvent(object):

    """

    A Python wrapper for the Google GEvent object.

    Events can be attached to any object derived from GOverlayBase with the

    add_event() call.

    For more information please see the Google Maps API Reference:

     http://code.google.com/apis/maps/documentation/reference.html#GEvent

    Example:

      from django.shortcuts import render_to_response

      from django.contrib.gis.maps.google import GoogleMap, GEvent, GPolyline

      def sample_request(request):

          polyline = GPolyline('LINESTRING(101 26, 112 26, 102 31)')

          event = GEvent('click', 

            'function() { location.href = "http://www.google.com"}')

          polyline.add_event(event)

          return render_to_response('mytemplate.html', 

          {'google' : GoogleMap(polylines=[polyline])})

    """

    def __init__(self, event, action):

        """

        Initializes a GEvent object. 

        Parameters:

        event: 

          string for the event, such as 'click'. The event must be a valid

          event for the object in the Google Maps API. 

          There is no validation of the event type within Django.

        action:

          string containing a Javascript function, such as 

          'function() { location.href = "newurl";}'

          The string must be a valid Javascript function. Again there is no 

          validation fo the function within Django.

        """

        self.event = event

        self.action = action

    def __unicode__(self):

        "Returns the parameter part of a GEvent."

        return mark_safe('"%s", %s' %(self.event, self.action))

class GOverlayBase(object):

    def __init__(self):

        self.events = []

    def latlng_from_coords(self, coords):

        "Generates a JavaScript array of GLatLng objects for the given coordinates."

        return '[%s]' % ','.join(['new GLatLng(%s,%s)' % (y, x) for x, y in coords])

    def add_event(self, event):

        "Attaches a GEvent to the overlay object."

        self.events.append(event)

    def __unicode__(self):

        "The string representation is the JavaScript API call."

        return mark_safe('%s(%s)' % (self.__class__.__name__, self.js_params))

class GPolygon(GOverlayBase):

    """

    A Python wrapper for the Google GPolygon object.  For more information

    please see the Google Maps API Reference:

     http://code.google.com/apis/maps/documentation/reference.html#GPolygon

    """

    def __init__(self, poly, 

                 stroke_color='#0000ff', stroke_weight=2, stroke_opacity=1,

                 fill_color='#0000ff', fill_opacity=0.4):

        """

        The GPolygon object initializes on a GEOS Polygon or a parameter that

        may be instantiated into GEOS Polygon.  Please note that this will not

        depict a Polygon's internal rings.

        Keyword Options:

          stroke_color:

            The color of the polygon outline. Defaults to '#0000ff' (blue).

          stroke_weight:

            The width of the polygon outline, in pixels.  Defaults to 2.

          stroke_opacity:

            The opacity of the polygon outline, between 0 and 1.  Defaults to 1.

          fill_color:

            The color of the polygon fill.  Defaults to '#0000ff' (blue).

          fill_opacity:

            The opacity of the polygon fill.  Defaults to 0.4.

        """

        if isinstance(poly, basestring): poly = fromstr(poly)

        if isinstance(poly, (tuple, list)): poly = Polygon(poly)

        if not isinstance(poly, Polygon): 

            raise TypeError('GPolygon may only initialize on GEOS Polygons.')

        # Getting the envelope of the input polygon (used for automatically

        # determining the zoom level).

        self.envelope = poly.envelope

        # Translating the coordinates into a JavaScript array of 

        # Google `GLatLng` objects.

        self.points = self.latlng_from_coords(poly.shell.coords)

        # Stroke settings.

        self.stroke_color, self.stroke_opacity, self.stroke_weight = stroke_color, stroke_opacity, stroke_weight

        # Fill settings.

        self.fill_color, self.fill_opacity = fill_color, fill_opacity

        super(GPolygon, self).__init__()

    @property

    def js_params(self):

        return '%s, "%s", %s, %s, "%s", %s' % (self.points, self.stroke_color, self.stroke_weight, self.stroke_opacity,

                                               self.fill_color, self.fill_opacity)

class GPolyline(GOverlayBase):

    """

    A Python wrapper for the Google GPolyline object.  For more information

    please see the Google Maps API Reference:

     http://code.google.com/apis/maps/documentation/reference.html#GPolyline

    """

    def __init__(self, geom, color='#0000ff', weight=2, opacity=1):

        """

        The GPolyline object may be initialized on GEOS LineStirng, LinearRing,

        and Polygon objects (internal rings not supported) or a parameter that

        may instantiated into one of the above geometries.

        Keyword Options:

          color:

            The color to use for the polyline.  Defaults to '#0000ff' (blue).

          weight:

            The width of the polyline, in pixels.  Defaults to 2.

          opacity:

            The opacity of the polyline, between 0 and 1.  Defaults to 1.

        """

        # If a GEOS geometry isn't passed in, try to contsruct one.

        if isinstance(geom, basestring): geom = fromstr(geom)

        if isinstance(geom, (tuple, list)): geom = Polygon(geom)

        # Generating the lat/lng coordinate pairs.

        if isinstance(geom, (LineString, LinearRing)):

            self.latlngs = self.latlng_from_coords(geom.coords)

        elif isinstance(geom, Polygon):

            self.latlngs = self.latlng_from_coords(geom.shell.coords)

        else:

            raise TypeError('GPolyline may only initialize on GEOS LineString, LinearRing, and/or Polygon geometries.')

        # Getting the envelope for automatic zoom determination.

        self.envelope = geom.envelope

        self.color, self.weight, self.opacity = color, weight, opacity

        super(GPolyline, self).__init__()

    @property

    def js_params(self):

        return '%s, "%s", %s, %s' % (self.latlngs, self.color, self.weight, self.opacity)

class GMarker(GOverlayBase):

    """

    A Python wrapper for the Google GMarker object.  For more information

    please see the Google Maps API Reference:

     http://code.google.com/apis/maps/documentation/reference.html#GMarker

    Example:

      from django.shortcuts import render_to_response

      from django.contrib.gis.maps.google.overlays import GMarker, GEvent

      def sample_request(request):

          marker = GMarker('POINT(101 26)')

          event = GEvent('click', 

                         'function() { location.href = "http://www.google.com"}')

          marker.add_event(event)

          return render_to_response('mytemplate.html', 

                 {'google' : GoogleMap(markers=[marker])})

    """

    def __init__(self, geom, title=None):

        """

        The GMarker object may initialize on GEOS Points or a parameter

        that may be instantiated into a GEOS point.  Keyword options map to

        GMarkerOptions -- so far only the title option is supported.

        Keyword Options:

         title: 

           Title option for GMarker, will be displayed as a tooltip.

        """

        # If a GEOS geometry isn't passed in, try to construct one.

        if isinstance(geom, basestring): geom = fromstr(geom)

        if isinstance(geom, (tuple, list)): geom = Point(geom)

        if isinstance(geom, Point):

            self.latlng = self.latlng_from_coords(geom.coords)

        else:

            raise TypeError('GMarker may only initialize on GEOS Point geometry.')

        # Getting the envelope for automatic zoom determination.

        self.envelope = geom.envelope

        # TODO: Add support for more GMarkerOptions

        self.title = title

        super(GMarker, self).__init__()

    def latlng_from_coords(self, coords):

        return 'new GLatLng(%s,%s)' %(coords[1], coords[0])

    def options(self):

        result = []

        if self.title: result.append('title: "%s"' % self.title) 

        return '{%s}' % ','.join(result)

    @property

    def js_params(self):

        return '%s, %s' % (self.latlng, self.options())