##############################################################################
#
# Copyright (c) 2001, 2002 Zope Corporation and Contributors.
# All Rights Reserved.
#
# This software is subject to the provisions of the Zope Public License,
# Version 2.1 (ZPL).  A copy of the ZPL should accompany this distribution.
# THIS SOFTWARE IS PROVIDED "AS IS" AND ANY AND ALL EXPRESS OR IMPLIED
# WARRANTIES ARE DISCLAIMED, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
# WARRANTIES OF TITLE, MERCHANTABILITY, AGAINST INFRINGEMENT, AND FITNESS
# FOR A PARTICULAR PURPOSE.
#
##############################################################################
"""Browser configuration code

$Id$
"""
import os
import sys

from zope.interface import implements, Interface
from zope.publisher.interfaces import NotFound
from zope.security.checker import CheckerPublic, Checker
from zope.security.checker import defineChecker
from zope.configuration.exceptions import ConfigurationError
from zope.app.component.interface import provideInterface
from zope.publisher.interfaces.browser import IBrowserRequest
from zope.publisher.interfaces.browser import IDefaultBrowserLayer
from zope.publisher.interfaces.browser import IBrowserPublisher
from zope.app.component.metaconfigure import handler
from zope.app.publisher.browser import BrowserView
from z3meld.meldtemplatefile import MeldTemplateFile

def page(_context, name, permission, for_,
         layer=IDefaultBrowserLayer, template=None, transform=None,
         ):
    required = {}

    permission = _handle_permission(_context, permission)

    if not template:
        raise ConfigurationError("Must specify a template")

    template = os.path.abspath(str(_context.path(template)))
    if not os.path.isfile(template):
        raise ConfigurationError("No such file", template)

    required['__getitem__'] = permission

    new_class = MeldViewClass(template, name=name, transform=transform)

    for n in ('__call__', 'browserDefault', 'publishTraverse'):
        required[n] = permission

    _handle_for(_context, for_)

    defineChecker(MeldViewClass, Checker(required))

    _context.action(
        discriminator = ('view', for_, name, IBrowserRequest, layer),
        callable = handler,
        args = ('provideAdapter',
                (for_, layer), Interface, name, new_class,
                _context.info),
        )

def _handle_permission(_context, permission):
    if permission == 'zope.Public':
        permission = CheckerPublic

    return permission

def _handle_for(_context, for_):
    if for_ is not None:
        _context.action(
            discriminator = None,
            callable = provideInterface,
            args = ('', for_)
            )

def _handle_for(_context, for_):
    if for_ is not None:
        _context.action(
            discriminator = None,
            callable = provideInterface,
            args = ('', for_)
            )

class MeldViewClass(BrowserView):

    implements(IBrowserPublisher)

    def __init__(self, filename, name, _prefix=None, transform=None):
        if _prefix is None:
            _prefix = sys._getframe(1).f_globals
        self.__name__ = name
        self.template = MeldTemplateFile(filename, _prefix,
                                         transform=transform)

    def publishTraverse(self, request, name):
        raise NotFound(self, name, request)

    def index(self):
        result = self.template(self.context, self.request)
        response = self.request.response
        if not response.getHeader("Content-Type"):
            response.setHeader("Content-Type", self.template.content_type)
        return result

    def browserDefault(self, request):
        return (self.index, ())

    def __call__(self, context, request):
        self.context = context
        self.request = request
        return self