#!/usr/bin/env python2
#-*- coding: utf-8 -*-

# SàT: a XMPP client
# Copyright (C) 2009-2016 Jérôme Poisson (goffi@goffi.org)

# This program is free software: you can redistribute it and/or modify
# it under the terms of the GNU Affero General Public License as published by
# the Free Software Foundation, either version 3 of the License, or
# (at your option) any later version.

# This program is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
# GNU Affero General Public License for more details.

# You should have received a copy of the GNU Affero General Public License
# along with this program.  If not, see <http://www.gnu.org/licenses/>.

from sat.core.constants import Const as C
import sys
import os
import argparse
from ConfigParser import SafeConfigParser as Parser
from ConfigParser import NoOptionError
import re
from datetime import datetime
from xml.dom import minidom

#consts
NAME = u"bridge_constructor"
__version__ = C.APP_VERSION
DEST_DIR_DEFAULT = "generated"
DESCRIPTION = u"""{name} Copyright (C) 2009-2016 Jérôme Poisson (aka Goffi)

This script construct a SàT bridge using the given protocol

This program comes with ABSOLUTELY NO WARRANTY;
This is free software, and you are welcome to redistribute it
under certain conditions.
""".format(name=NAME, version=__version__)
# TODO: move protocoles in separate files (plugins?)
MANAGED_PROTOCOLES = ['dbus', 'mediawiki', 'dbus-xml']
DEFAULT_PROTOCOLE = 'dbus'

# flags used method/signal declaration (not to be confused with constructor flags)
DECLARATION_FLAGS = ['deprecated', 'async']

ENV_OVERRIDE = "SAT_BRIDGE_CONST_"  # Prefix used to override a constant



class ParseError(Exception):
    #Used when the signature parsing is going wrong (invalid signature ?)
    pass


class Constructor(object):

    def __init__(self, bridge_template, options):
        self.bridge_template = bridge_template
        self.args = options

    def getValues(self, name):
        """Return values of a function in a dict
        @param name: Name of the function to get
        @return: dict, each key has the config value or None if the value is not set"""
        function = {}
        for option in ['type', 'category', 'sig_in', 'sig_out', 'doc']:
            try:
                value = self.bridge_template.get(name, option)
            except NoOptionError:
                value = None
            function[option] = value
        return function

    def getDefault(self, name):
        """Return default values of a function in a dict
        @param name: Name of the function to get
        @return: dict, each key is the integer param number (no key if no default value)"""
        default_dict = {}
        def_re = re.compile(r"param_(\d+)_default")

        for option in self.bridge_template.options(name):
            match = def_re.match(option)
            if match:
                try:
                    idx = int(match.group(1))
                except ValueError:
                    raise ParseError("Invalid value [%s] for parameter number" % match.group(1))
                default_dict[idx] = self.bridge_template.get(name, option)

        return default_dict

    def getFlags(self, name):
        """Return list of flags set for this function
        @param name: Name of the function to get
        @return: List of flags (string)"""
        flags = []
        for option in self.bridge_template.options(name):
            if option in DECLARATION_FLAGS:
                flags.append(option)
        return flags

    def getArgumentsDoc(self, name):
        """Return documentation of arguments
        @param name: Name of the function to get
        @return: dict, each key is the integer param number (no key if no argument doc), value is a tuple (name, doc)"""
        doc_dict = {}
        option_re = re.compile(r"doc_param_(\d+)")
        value_re = re.compile(r"^(\w+): (.*)$", re.MULTILINE | re.DOTALL)
        for option in self.bridge_template.options(name):
            if option == 'doc_return':
                doc_dict['return'] = self.bridge_template.get(name, option)
                continue
            match = option_re.match(option)
            if match:
                try:
                    idx = int(match.group(1))
                except ValueError:
                    raise ParseError("Invalid value [%s] for parameter number" % match.group(1))
                value_match = value_re.match(self.bridge_template.get(name, option))
                if not value_match:
                    raise ParseError("Invalid value for parameter doc [%i]" % idx)
                doc_dict[idx] = (value_match.group(1), value_match.group(2))
        return doc_dict

    def getDoc(self, name):
        """Return documentation of the method
        @param name: Name of the function to get
        @return: string documentation, or None"""
        if self.bridge_template.has_option(name, "doc"):
            return self.bridge_template.get(name, "doc")
        return None

    def argumentsParser(self, signature):
        """Generator which return individual arguments signatures from a global signature"""
        start = 0
        i = 0

        while i < len(signature):
            if signature[i] not in ['b', 'y', 'n', 'i', 'x', 'q', 'u', 't', 'd', 's', 'a']:
                raise ParseError("Unmanaged attribute type [%c]" % signature[i])

            if signature[i] == 'a':
                i += 1
                if signature[i] != '{' and signature[i] != '(':  # FIXME: must manage tuples out of arrays
                    i += 1
                    yield signature[start:i]
                    start = i
                    continue  # we have a simple type for the array
                opening_car = signature[i]
                assert(opening_car in ['{', '('])
                closing_car = '}' if opening_car == '{' else ')'
                opening_count = 1
                while (True):  # we have a dict or a list of tuples
                    i += 1
                    if i >= len(signature):
                        raise ParseError("missing }")
                    if signature[i] == opening_car:
                        opening_count += 1
                    if signature[i] == closing_car:
                        opening_count -= 1
                        if opening_count == 0:
                            break
            i += 1
            yield signature[start:i]
            start = i

    def getArguments(self, signature, name=None, default=None, unicode_protect=False):
        """Return arguments to user given a signature

        @param signature: signature in the short form (using s,a,i,b etc)
        @param name: dictionary of arguments name like given by getArguments
        @param default: dictionary of default values, like given by getDefault
        @param unicode_protect: activate unicode protection on strings (return strings as unicode(str))
        @return: list of arguments that correspond to a signature (e.g.: "sss" return "arg1, arg2, arg3")
        """
        idx = 0
        attr_string = []

        for arg in self.argumentsParser(signature):
            attr_string.append(("unicode(%(name)s)%(default)s" if (unicode_protect and arg == 's') else "%(name)s%(default)s") % {
                'name': name[idx][0] if (name and idx in name) else "arg_%i" % idx,
                'default': "=" + default[idx] if (default and idx in default) else ''})
                # give arg_1, arg2, etc or name1, name2=default, etc.
                #give unicode(arg_1), unicode(arg_2), etc. if unicode_protect is set and arg is a string
            idx += 1

        return ", ".join(attr_string)

    def generateCoreSide(self):
        """create the constructor in SàT core side (backend)"""
        raise NotImplementedError

    def generateFrontendSide(self):
        """create the constructor in SàT frontend side"""
        raise NotImplementedError

    def finalWrite(self, filename, file_buf):
        """Write the final generated file in [dest dir]/filename

        @param filename: name of the file to generate
        @param file_buf: list of lines (stings) of the file
        """
        if os.path.exists(self.args.dest_dir) and not os.path.isdir(self.args.dest_dir):
            print ("The destination dir [%s] can't be created: a file with this name already exists !")
            sys.exit(1)
        try:
            if not os.path.exists(self.args.dest_dir):
                os.mkdir(self.args.dest_dir)
            full_path = os.path.join(self.args.dest_dir, filename)
            if os.path.exists(full_path) and not self.args.force:
                print ("The destination file [%s] already exists ! Use --force to overwrite it" % full_path)
            try:
                with open(full_path, 'w') as dest_file:
                    dest_file.write('\n'.join(file_buf))
            except IOError:
                print ("Can't open destination file [%s]" % full_path)
        except OSError:
            print("It's not possible to generate the file, check your permissions")
            exit(1)


class MediawikiConstructor(Constructor):

    def __init__(self, bridge_template, options):
        Constructor.__init__(self, bridge_template, options)
        self.core_template = "mediawiki_template.tpl"
        self.core_dest = "mediawiki.wiki"

    def _addTextDecorations(self, text):
        """Add text decorations like coloration or shortcuts"""

        def anchor_link(match):
            link = match.group(1)
            #we add anchor_link for [method_name] syntax:
            if link in self.bridge_template.sections():
                return "[[#%s|%s]]" % (link, link)
            print ("WARNING: found an anchor link to an unknown method")
            return link

        return re.sub(r"\[(\w+)\]", anchor_link, text)

    def _wikiParameter(self, name, sig_in):
        """Format parameters with the wiki syntax
        @param name: name of the function
        @param sig_in: signature in
        @return: string of the formated parameters"""
        arg_doc = self.getArgumentsDoc(name)
        arg_default = self.getDefault(name)
        args_str = self.getArguments(sig_in)
        args = args_str.split(', ') if args_str else []  # ugly but it works :)
        wiki = []
        for i in range(len(args)):
            if i in arg_doc:
                name, doc = arg_doc[i]
                doc = '\n:'.join(doc.rstrip('\n').split('\n'))
                wiki.append("; %s: %s" % (name, self._addTextDecorations(doc)))
            else:
                wiki.append("; arg_%d: " % i)
            if i in arg_default:
                wiki.append(":''DEFAULT: %s''" % arg_default[i])
        return "\n".join(wiki)

    def _wikiReturn(self, name):
        """Format return doc with the wiki syntax
        @param name: name of the function
        """
        arg_doc = self.getArgumentsDoc(name)
        wiki = []
        if 'return' in arg_doc:
            wiki.append('\n|-\n! scope=row | return value\n|')
            wiki.append('<br />\n'.join(self._addTextDecorations(arg_doc['return']).rstrip('\n').split('\n')))
        return "\n".join(wiki)

    def generateCoreSide(self):
        signals_part = []
        methods_part = []
        sections = self.bridge_template.sections()
        sections.sort()
        for section in sections:
            function = self.getValues(section)
            print ("Adding %s %s" % (section, function["type"]))
            async_msg = """<br />'''This method is asynchronous'''"""
            deprecated_msg = """<br />'''<font color="#FF0000">/!\ WARNING /!\ : This method is deprecated, please don't use it !</font>'''"""
            signature_signal = \
            """\
! scope=row | signature
| %s
|-\
""" % function['sig_in']
            signature_method = \
            """\
! scope=row | signature in
| %s
|-
! scope=row | signature out
| %s
|-\
""" % (function['sig_in'], function['sig_out'])
            completion = {
                'signature': signature_signal if function['type'] == "signal" else signature_method,
                'sig_out': function['sig_out'] or '',
                'category': function['category'],
                'name': section,
                'doc': self.getDoc(section) or "FIXME: No description available",
                'async': async_msg if "async" in self.getFlags(section) else "",
                'deprecated': deprecated_msg if "deprecated" in self.getFlags(section) else "",
                'parameters': self._wikiParameter(section, function['sig_in']),
                'return': self._wikiReturn(section) if function['type'] == 'method' else ''}

            dest = signals_part if function['type'] == "signal" else methods_part
            dest.append("""\
== %(name)s ==
''%(doc)s''
%(deprecated)s
%(async)s
{| class="wikitable" style="text-align:left; width:80%%;"
! scope=row | category
| %(category)s
|-
%(signature)s
! scope=row | parameters
|
%(parameters)s%(return)s
|}
""" % completion)

        #at this point, signals_part, and methods_part should be filled,
        #we just have to place them in the right part of the template
        core_bridge = []
        try:
            with open(self.core_template) as core_template:
                for line in core_template:
                    if line.startswith('##SIGNALS_PART##'):
                        core_bridge.extend(signals_part)
                    elif line.startswith('##METHODS_PART##'):
                        core_bridge.extend(methods_part)
                    elif line.startswith('##TIMESTAMP##'):
                        core_bridge.append('Generated on %s' % datetime.now())
                    else:
                        core_bridge.append(line.replace('\n', ''))
        except IOError:
            print ("Can't open template file [%s]" % self.core_template)
            sys.exit(1)

        #now we write to final file
        self.finalWrite(self.core_dest, core_bridge)


class DbusConstructor(Constructor):

    def __init__(self, bridge_template, options):
        Constructor.__init__(self, bridge_template, options)
        self.core_template = "dbus_core_template.py"
        self.frontend_template = "dbus_frontend_template.py"
        self.frontend_dest = self.core_dest = "DBus.py"

    def generateCoreSide(self):
        signals_part = []
        methods_part = []
        direct_calls = []
        sections = self.bridge_template.sections()
        sections.sort()
        for section in sections:
            function = self.getValues(section)
            print ("Adding %s %s" % (section, function["type"]))
            default = self.getDefault(section)
            arg_doc = self.getArgumentsDoc(section)
            async = "async" in self.getFlags(section)
            completion = {
                'sig_in': function['sig_in'] or '',
                'sig_out': function['sig_out'] or '',
                'category': 'PLUGIN' if function['category'] == 'plugin' else 'CORE',
                'name': section,
                'args': self.getArguments(function['sig_in'], name=arg_doc, default=default)}

            if function["type"] == "signal":
                completion['body'] = "pass" if not self.args.debug else 'log.debug ("%s")' % section
                signals_part.append("""\
    @dbus.service.signal(const_INT_PREFIX+const_%(category)s_SUFFIX,
                         signature='%(sig_in)s')
    def %(name)s(self, %(args)s):
        %(body)s
""" % completion)
                direct_calls.append("""\
    def %(name)s(self, %(args)s):
        self.dbus_bridge.%(name)s(%(args)s)
""" % completion)

            elif function["type"] == "method":
                completion['debug'] = "" if not self.args.debug else 'log.debug ("%s")\n%s' % (section, 8 * ' ')
                completion['args_result'] = self.getArguments(function['sig_in'], name=arg_doc, unicode_protect=self.args.unicode)
                completion['async_comma'] = ', ' if async and function['sig_in'] else ''
                completion['async_args_def'] = 'callback=None, errback=None' if async else ''
                completion['async_args_call'] = 'callback=callback, errback=errback' if async else ''
                completion['async_callbacks'] = "('callback', 'errback')" if async else "None"
                methods_part.append("""\
    @dbus.service.method(const_INT_PREFIX+const_%(category)s_SUFFIX,
                         in_signature='%(sig_in)s', out_signature='%(sig_out)s',
                         async_callbacks=%(async_callbacks)s)
    def %(name)s(self, %(args)s%(async_comma)s%(async_args_def)s):
        %(debug)sreturn self._callback("%(name)s", %(args_result)s%(async_comma)s%(async_args_call)s)
""" % completion)

        #at this point, signals_part, methods_part and direct_calls should be filled,
        #we just have to place them in the right part of the template
        core_bridge = []
        const_override_pref = filter(lambda env: env.startswith(ENV_OVERRIDE), os.environ)
        const_override = [env[len(ENV_OVERRIDE):] for env in const_override_pref]
        try:
            with open(self.core_template) as core_template:
                for line in core_template:
                    if line.startswith('##SIGNALS_PART##'):
                        core_bridge.extend(signals_part)
                    elif line.startswith('##METHODS_PART##'):
                        core_bridge.extend(methods_part)
                    elif line.startswith('##DIRECT_CALLS##'):
                        core_bridge.extend(direct_calls)
                    else:
                        if line.startswith('const_'):
                            const_name = line[len('const_'):line.find(' = ')]
                            if const_name in const_override:
                                print ("const %s overriden" % const_name)
                                core_bridge.append('const_%s = %s' % (const_name, os.environ[ENV_OVERRIDE + const_name]))
                                continue
                        core_bridge.append(line.replace('\n', ''))
        except IOError:
            print ("Can't open template file [%s]" % self.core_template)
            sys.exit(1)

        #now we write to final file
        self.finalWrite(self.core_dest, core_bridge)

    def generateFrontendSide(self):
        methods_part = []
        sections = self.bridge_template.sections()
        sections.sort()
        for section in sections:
            function = self.getValues(section)
            print ("Adding %s %s" % (section, function["type"]))
            default = self.getDefault(section)
            arg_doc = self.getArgumentsDoc(section)
            async = "async" in self.getFlags(section)
            completion = {
                'sig_in': function['sig_in'] or '',
                'sig_out': function['sig_out'] or '',
                'category': 'plugin' if function['category'] == 'plugin' else 'core',
                'name': section,
                'args': self.getArguments(function['sig_in'], name=arg_doc, default=default)}

            if function["type"] == "method":
                # XXX: we can manage blocking call in the same way as async one: if callback is None the call will be blocking
                completion['debug'] = "" if not self.args.debug else 'log.debug ("%s")\n%s' % (section, 8 * ' ')
                completion['args_result'] = self.getArguments(function['sig_in'], name=arg_doc)
                completion['async_args'] = 'callback=None, errback=None'
                completion['async_comma'] = ', ' if function['sig_in'] else ''
                completion['error_handler'] = """if callback is None:
            error_handler = None
        else:
            if errback is None:
                errback = log.error
            error_handler = lambda err:errback(dbus_to_bridge_exception(err))
        """
                if async:
                    completion['blocking_call'] = ''
                    completion['async_args_result'] = 'timeout=const_TIMEOUT, reply_handler=callback, error_handler=error_handler'
                else:
                    # XXX: To have a blocking call, we must have not reply_handler, so we test if callback exists, and add reply_handler only in this case
                    completion['blocking_call'] = """kwargs={}
        if callback is not None:
            kwargs['timeout'] = const_TIMEOUT
            kwargs['reply_handler'] = callback
            kwargs['error_handler'] = error_handler
        """
                    completion['async_args_result'] = '**kwargs'
                result = "self.db_%(category)s_iface.%(name)s(%(args_result)s%(async_comma)s%(async_args_result)s)" % completion
                completion['result'] = ("unicode(%s)" if self.args.unicode and function['sig_out'] == 's' else "%s") % result
                methods_part.append("""\
    def %(name)s(self, %(args)s%(async_comma)s%(async_args)s):
        %(error_handler)s%(blocking_call)s%(debug)sreturn %(result)s
""" % completion)

        #at this point, methods_part should be filled,
        #we just have to place it in the right part of the template
        frontend_bridge = []
        const_override_pref = filter(lambda env: env.startswith(ENV_OVERRIDE), os.environ)
        const_override = [env[len(ENV_OVERRIDE):] for env in const_override_pref]
        try:
            with open(self.frontend_template) as frontend_template:
                for line in frontend_template:
                    if line.startswith('##METHODS_PART##'):
                        frontend_bridge.extend(methods_part)
                    else:
                        if line.startswith('const_'):
                            const_name = line[len('const_'):line.find(' = ')]
                            if const_name in const_override:
                                print ("const %s overriden" % const_name)
                                frontend_bridge.append('const_%s = %s' % (const_name, os.environ[ENV_OVERRIDE + const_name]))
                                continue
                        frontend_bridge.append(line.replace('\n', ''))
        except IOError:
            print ("Can't open template file [%s]" % self.frontend_template)
            sys.exit(1)

        #now we write to final file
        self.finalWrite(self.frontend_dest, frontend_bridge)


class DbusXmlConstructor(Constructor):
    """Constructor for DBus XML syntaxt (used by Qt frontend)"""

    def __init__(self, bridge_template, options):
        Constructor.__init__(self, bridge_template, options)

        self.template = "dbus_xml_template.xml"
        self.core_dest = "org.goffi.sat.xml"
        self.default_annotation = {'a{ss}': 'StringDict',
                                   'a(sa{ss}as)': 'QList<Contact>',
                                   'a{i(ss)}': 'HistoryT',
                                   'a(sss)': 'QList<MenuT>',
                                   'a{sa{s(sia{ss})}}': 'PresenceStatusT',
                                   }

    def generateCoreSide(self):
        try:
            doc = minidom.parse(self.template)
            interface_elt = doc.getElementsByTagName('interface')[0]
        except IOError:
            print ("Can't access template")
            sys.exit(1)
        except IndexError:
            print ("Template error")
            sys.exit(1)

        sections = self.bridge_template.sections()
        sections.sort()
        for section in sections:
            function = self.getValues(section)
            print ("Adding %s %s" % (section, function["type"]))
            new_elt = doc.createElement('method' if function["type"] == 'method' else 'signal')
            new_elt.setAttribute('name', section)

            idx = 0
            args_doc = self.getArgumentsDoc(section)
            for arg in self.argumentsParser(function['sig_in'] or ''):
                arg_elt = doc.createElement('arg')
                arg_elt.setAttribute('name', args_doc[idx][0] if idx in args_doc else "arg_%i" % idx)
                arg_elt.setAttribute('type', arg)
                _direction = 'in' if function["type"] == 'method' else 'out'
                arg_elt.setAttribute('direction', _direction)
                new_elt.appendChild(arg_elt)
                if "annotation" in self.args.flags:
                    if arg in self.default_annotation:
                        annot_elt = doc.createElement("annotation")
                        annot_elt.setAttribute('name', "com.trolltech.QtDBus.QtTypeName.In%d" % idx)
                        annot_elt.setAttribute('value', self.default_annotation[arg])
                        new_elt.appendChild(annot_elt)
                idx += 1

            if function['sig_out']:
                arg_elt = doc.createElement('arg')
                arg_elt.setAttribute('type', function['sig_out'])
                arg_elt.setAttribute('direction', 'out')
                new_elt.appendChild(arg_elt)
                if "annotation" in self.args.flags:
                    if function['sig_out'] in self.default_annotation:
                        annot_elt = doc.createElement("annotation")
                        annot_elt.setAttribute('name', "com.trolltech.QtDBus.QtTypeName.Out0")
                        annot_elt.setAttribute('value', self.default_annotation[function['sig_out']])
                        new_elt.appendChild(annot_elt)

            interface_elt.appendChild(new_elt)

        #now we write to final file
        self.finalWrite(self.core_dest, [doc.toprettyxml()])


class ConstructorError(Exception):
    pass


class ConstructorFactory(object):
    def create(self, bridge_template, options):
        if options.protocole == 'dbus':
            return DbusConstructor(bridge_template, options)
        elif options.protocole == 'mediawiki':
            return MediawikiConstructor(bridge_template, options)
        elif options.protocole == 'dbus-xml':
            return DbusXmlConstructor(bridge_template, options)

        raise ConstructorError('Unknown constructor type')


class BridgeConstructor(object):
    def __init__(self):
        self.args = None

    def parse_args(self):
        """Check command line options"""
        parser = argparse.ArgumentParser(description=DESCRIPTION, formatter_class=argparse.RawDescriptionHelpFormatter)

        parser.add_argument("--version", action="version", version= __version__)
        parser.add_argument("-p", "--protocole", choices=MANAGED_PROTOCOLES, default=DEFAULT_PROTOCOLE,
            help="generate bridge using PROTOCOLE (default: %(default)s)") # (default: %s, possible values: [%s])" % (DEFAULT_PROTOCOLE, ", ".join(MANAGED_PROTOCOLES)))
        parser.add_argument("-s", "--side", choices=("core", "frontend"), default="core",
            help="which side of the bridge do you want to make ?") # (default: %default, possible values: [core, frontend])")
        parser.add_argument("-t", "--template", type=file, default='bridge_template.ini',
            help="use TEMPLATE to generate bridge (default: %(default)s)")
        parser.add_argument("-f", "--force", action="store_true",
            help=("force overwritting of existing files"))
        parser.add_argument("-d", "--debug", action="store_true",
            help=("add debug information printing"))
        parser.add_argument("--no-unicode", action="store_false", dest="unicode",
            help=("remove unicode type protection from string results"))
        parser.add_argument("--flags", nargs='+', default=[],
            help=("constructors' specific flags"))
        parser.add_argument("--dest-dir", default=DEST_DIR_DEFAULT,
            help=("directory when the generated files will be written (default: %(default)s"))

        return parser.parse_args()

    def go(self):
        args = self.parse_args()
        self.template = Parser()
        try:
            self.template.readfp(args.template)
        except IOError:
            print ("The template file doesn't exist or is not accessible")
            exit(1)
        constructor = ConstructorFactory().create(self.template, args)
        if args.side == "core":
            constructor.generateCoreSide()
        elif args.side == "frontend":
            constructor.generateFrontendSide()

if __name__ == "__main__":
    bc = BridgeConstructor()
    bc.go()