"""
request dispatcher
"""

__all__ = ['MapserverMiddleware', 'SVGSiteMap']

import os
from pygraphviz import AGraph
from webob import Request, exc

class MapserverMiddleware(object):
    """silly middleware to serve just the svg"""
    def __init__(self, app, svgmap, path='/map'):
        self.app
        self.svgmap = svgmap
        self.path = path

    def __call__(self, environ, start_response):
        request = Request(environ)
        if request.path_info == self.path or not self.path:
            content = file(self.svgmap).read()
            return Response(content_type='image/svg+xml', body=content)
        return app(environ, start_response)
    

class SVGSiteMap(object):

    ### class level variables
    defaults = { 'app': None,
                 'name': 'k0s.org',
                 'file': None,
                 'output': None,
                 'bgcolor': 'black',
                 'fontcolor': 'white',
                 'fontname': 'Helvetica',
                 'nodecolor': 'aqua',
                 'edgecolor': 'lime',
                 'shape': 'box'
                 }

    def __init__(self, app, **kw):
        self.app = app
        self.edges = {}
        for key in self.defaults:
            setattr(self, key, kw.get(key, self.defaults[key]))
        assert self.output, "Please give an output file"
        assert self.file, "Cannot save file!"
        if os.path.exists(self.file):
            self.graph = AGraph(self.file, directed=True)
            for edge in self.graph.edges():
                self.edges[(edge[0], edge[1])] = int(edge.attr['label'])
        else:
            self.graph = AGraph(directed=True)
        self.graph.graph_attr['title'] = self.name
        self.graph.graph_attr['label'] = self.name
        self.graph.graph_attr['fontname'] = self.fontname
        self.graph.graph_attr['fontcolor'] = self.fontcolor
        self.graph.graph_attr['bgcolor'] = self.bgcolor
        self.graph.node_attr['color'] = self.nodecolor
        self.graph.node_attr['fontcolor'] = self.fontcolor
        self.graph.node_attr[
        self.graph.node_attr['shape'] = self.shape
        self.graph.edge_attr['color'] = self.edgecolor
        self.graph.edge_attr['fontcolor'] = self.fontcolor
        
    ### methods dealing with HTTP
    def __call__(self, environ, start_response):
        request = Request(environ)
        import pdb; pdb.set_trace()
        return self.app(environ, start_response)

    def add(self, from_url, to_url):
        if (from_url, to_url) in self.edges:
            count = self.edges[(from_url, to_url)]
            count += 1
            self.edges[(from_url, to_url)] = count
            edge = self.graph.get_edge(from_url, to_url)
            edge.attr['label'] =  str(count)
        else:
            self.edges[(from_url, to_url)] = 1
            self.graph.add_edge(from_url, to_url, label='1')

        for url in from_url, to_url:
            node = self.graph.get_node(url)
            node.attr['label'] = url
            node.attr['href'] = url

        if self.file:
            self.graph.write(self.file)
        if self.output:
            self.graph.draw(self.output, prog='dot')