#!/usr/bin/python2.7 -E
#
# Copyright (c) 2013, Oracle and/or its affiliates. All rights reserved.
#
'''
Retrieve the default manifest for a service.
'''

import cgi
import logging
from lxml import etree
import os.path
import simplejson
import sys

from solaris_install import SCRIPT_LOGGER_NAME
from solaris_install.ai.server import Server

DEFAULT_DEFAULT_MANIFEST = "/usr/share/auto_install/manifest/default.xml"


def element_to_dict(element):
    '''Convert element to dictionary'''
    my_dict = dict()

    #for element in tree.getroot().iter(tag=etree.Element):
    for sub_element in element.iterchildren(tag=etree.Element):
        sub_dict = element_to_dict(sub_element)
        value = sub_dict[sub_element.tag]
        try:
            # add to existing list for this tag
            my_dict[sub_element.tag].append(value)
        except AttributeError:
            # turn existing entry into a list
            my_dict[sub_element.tag] = [my_dict[sub_element.tag], value]
        except KeyError:
            # add a new non-list entry
            my_dict[sub_element.tag] = value

    # Add attributes
    for key, value in element.items():
        my_dict['@' + key] = value

    # Add text sub-element
    if element.text is not None:
        my_dict['#text'] = element.text

    return {element.tag: my_dict}


def get_default_manifest(this_service):
    '''Retrieve the default manifest for this service'''
    manifest_file = None
    service = \
        Server.get_instance().get_services(filter_by_name=this_service)[0]
    manifest_file = os.path.join(service.image_path,
                                 'auto_install/default.xml')
    return manifest_file


def main():
    '''Main defaultManifest method'''
    # - locate correct default.xml file depending on the AI service
    # - convert XML file to element tree with etree
    # - convert element tree to dictionary (elements are not JSON serializable)
    # - convert dictionary to JSON with simplejson
    # - write output

    # process CGI params
    this_service = None
    try:
        form = cgi.FieldStorage()
        if ('service' in form):
            this_service = form['service'].value.strip('\'')
    except SystemExit:
        pass

    # Configure script logger to output to stderr so logging gets stored
    # in apache error_log
    logging.basicConfig(stream=sys.stderr, level=logging.INFO,
                        format="%(message)s")
    logging.getLogger(SCRIPT_LOGGER_NAME)

    # Ensure default handlers created are at the level we want here.
    for handler in logging.getLogger().handlers:
        handler.setLevel(logging.INFO)

    # Get the correct default.xml file for this AI service, or fall back
    # to the one in /usr/share/...
    manifest_file = DEFAULT_DEFAULT_MANIFEST
    if this_service is not None:
        manifest_file = get_default_manifest(this_service)

    # Create the XML parser
    parser = etree.XMLParser(remove_blank_text=True,
                             dtd_validation=True,
                             attribute_defaults=True)

    # parse the XML file
    try:
        tree = etree.parse(manifest_file, parser)
    except IOError, _error:
        print "Cannot access Manifest file [%s]" % (manifest_file)
    except etree.XMLSyntaxError, _error:
        print "XML syntax error in manifest [%s]" % (manifest_file)

    # convert from etree.Element to python dictionary
    my_dict = element_to_dict(tree.getroot())
    my_dict['auto_install']['ai_instance']['save_server'] = \
        Server.get_instance().wizard_saves_to_server

    # convert python dictionary to JSON
    out_text = simplejson.dumps(my_dict)

    # write output
    print out_text

if __name__ == "__main__":
    print "Content-Type: text/json\n"

    # Ensure we always make a valid response by catching
    # any exceptions that occur
    try:
        main()
    except:
        pass