import os.path

import paste.fileapp
from pylons import request
from pylons.middleware import error_document_template, media_path
from pylons.controllers import WSGIController
from tg import render

class ErrorController(WSGIController):
    """Generates error documents as and when they are required.

    The ErrorDocuments middleware forwards to ErrorController when error
    related status codes are returned from the application.

    This behaviour can be altered by changing the parameters to the
    ErrorDocuments middleware in your config/middleware.py file.
    """

    def document(self):
        """Render the error document"""
        resp = request.environ.get('pylons.original_response')
        template_vars = dict(prefix=request.environ.get('SCRIPT_NAME', ''),
                             code=request.params.get('code', resp.status_int),
                             message=request.params.get('message', resp.body))
        
        return render.render_genshi("error.html", template_vars)

    def img(self, id):
        """Serve stock images"""
        return self._serve_file(os.path.join(media_path, 'img', id))

    def style(self, id):
        """Serve stock stylesheets"""
        return self._serve_file(os.path.join(media_path, 'style', id))

    def _serve_file(self, path):
        """Call Paste's FileApp (a WSGI application) to serve the file
        at the specified path
        """
        fapp = paste.fileapp.FileApp(path)
        return fapp(request.environ, self.start_response)