# -*- coding: utf-8 -*-

"""
***************************************************************************
    layergroup.py
    ---------------------
    Date                 : November 2012
    Copyright            : (C) 2012 by David Winslow
    Email                : dwins at opengeo dot com
***************************************************************************
*                                                                         *
*   This program 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.                                   *
*                                                                         *
***************************************************************************
"""

__author__ = 'David Winslow'
__date__ = 'November 2012'
__copyright__ = '(C) 2012, David Winslow'

# This will get replaced with a git SHA1 when you do a git archive

__revision__ = '$Format:%H$'

from support import ResourceInfo, bbox, \
    write_bbox, write_string, xml_property, url


def _maybe_text(n):
    if n is None:
        return None
    else:
        return n.text


def _layer_list(node):
    if node is not None:
        return [_maybe_text(n.find('name')) for n in node.findall('layer')]


def _style_list(node):
    if node is not None:
        return [_maybe_text(n.find('name')) for n in node.findall('style')]


def _write_layers(builder, layers):
    builder.start('layers', dict())
    for l in layers:
        builder.start('layer', dict())
        if l is not None:
            builder.start('name', dict())
            builder.data(l)
            builder.end('name')
        builder.end('layer')
    builder.end('layers')


def _write_styles(builder, styles):
    builder.start('styles', dict())
    for s in styles:
        builder.start('style', dict())
        if s is not None:
            builder.start('name', dict())
            builder.data(s)
            builder.end('name')
        builder.end('style')
    builder.end('styles')


class LayerGroup(ResourceInfo):
    """Represents a layer group in geoserver.
    """

    resource_type = 'layerGroup'
    save_method = 'PUT'

    def __init__(self, catalog, name):
        super(LayerGroup, self).__init__()

        assert isinstance(name, basestring)

        self.catalog = catalog
        self.name = name

    @property
    def href(self):
        return url(self.catalog.service_url, ['layergroups', self.name + '.xml'
                   ])

    styles = xml_property('styles', _style_list)
    layers = xml_property('layers', _layer_list)
    bounds = xml_property('bounds', bbox)

    writers = dict(name=write_string('name'), styles=_write_styles,
                   layers=_write_layers, bounds=write_bbox('bounds'))

    def __str__(self):
        return '<LayerGroup %s>' % self.name

    __repr__ = __str__


class UnsavedLayerGroup(LayerGroup):

    save_method = 'POST'

    def __init__(self, catalog, name, layers, styles, bounds):
        super(UnsavedLayerGroup, self).__init__(catalog, name)
        self.dirty.update(name=name, layers=layers, styles=styles,
                          bounds=bounds)

    @property
    def href(self):
        return '%s/layergroups?name=%s' % (self.catalog.service_url, self.name)