#
#    Metrix++, Copyright 2009-2013, Metrix++ Project
#    Link: http://metrixplusplus.sourceforge.net
#    
#    This file is a part of Metrix++ Tool.
#    
#    Metrix++ 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, version 3 of the License.
#    
#    Metrix++ 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 General Public License for more details.
#    
#    You should have received a copy of the GNU General Public License
#    along with Metrix++.  If not, see <http://www.gnu.org/licenses/>.
#

import logging

class Data(object):

    def __init__(self):
        self.data = {}

    def get_data(self, namespace, field):
        if namespace not in self.data.keys():
            return None
        if field not in self.data[namespace].keys():
            return None
        return self.data[namespace][field]

    def set_data(self, namespace, field, value):
        if namespace not in self.data:
            self.data[namespace] = {}
        self.data[namespace][field] = value
    
    def iterate_namespaces(self):
        for namespace in self.data.keys():
            yield namespace
            
    def iterate_fields(self, namespace):
        for field in self.data[namespace].keys():
            yield (field, self.data[namespace][field])

    def get_data_tree(self, namespaces=None):
        return self.data

    def __repr__(self):
        return object.__repr__(self) + " with data " + self.data.__repr__()


class LoadableData(Data):
    
    def __init__(self, loader, file_id, region_id):
        Data.__init__(self)
        self.loader = loader
        self.file_id = file_id
        self.region_id = region_id
        self.loaded_namespaces = []
        self.changed_namespaces = []

    def load_namespace(self, namespace):
        try:
            row = self.loader.db.get_row(namespace, self.file_id, self.region_id)
        except Exception:
            logging.debug("No data in the database for namespace: " + namespace)
            return
        if row == None:
            return 
        for column_name in row.keys():
            packager = self.loader.get_namespace(namespace).get_field_packager(column_name)
            if packager == None:
                continue
            if row[column_name] == None:
                continue
            Data.set_data(self, namespace, column_name, packager.unpack(row[column_name]))
        
    def set_data(self, namespace, field, value):
        if namespace not in self.changed_namespaces:
            self.changed_namespaces.append(namespace)
        return Data.set_data(self, namespace, field, value)

    def get_data(self, namespace, field):
        if namespace not in self.loaded_namespaces:
            self.loaded_namespaces.append(namespace)
            self.load_namespace(namespace)
        return Data.get_data(self, namespace, field)
    
    def is_namespace_updated(self, namespace):
        return namespace in self.changed_namespaces

    def is_namespace_loaded(self, namespace):
        return namespace in self.loaded_namespaces

    def get_data_tree(self, namespaces=None):
        if namespaces == None:
            namespaces = self.loader.iterate_namespace_names()
        for each in namespaces:
            self.load_namespace(each)
        return Data.get_data_tree(self)
    
class FileRegionData(LoadableData):
    
    class T(object):
        NONE      = 0x00
        GLOBAL    = 0x01
        CLASS     = 0x02
        STRUCT    = 0x04
        NAMESPACE = 0x08
        FUNCTION  = 0x10
        INTERFACE = 0x20
        ANY       = 0xFF
        
        def to_str(self, group):
            if group == self.NONE:
                return "none"
            elif group == self.GLOBAL:
                return "global"
            elif group == self.CLASS:
                return "class"
            elif group == self.STRUCT:
                return "struct"
            elif group == self.NAMESPACE:
                return "namespace"
            elif group == self.FUNCTION:
                return "function"
            elif group == self.INTERFACE:
                return "interface"
            else:
                assert(False)

    def __init__(self, loader, file_id, region_id, region_name, offset_begin, offset_end, line_begin, line_end, cursor_line, group, checksum):
        LoadableData.__init__(self, loader, file_id, region_id)
        self.name = region_name
        self.begin = offset_begin
        self.end = offset_end
        self.line_begin = line_begin
        self.line_end = line_end
        self.cursor = cursor_line
        self.group = group
        self.checksum = checksum
        
        self.children = []
    
    def get_id(self):
        return self.region_id

    def get_name(self):
        return self.name

    def get_offset_begin(self):
        return self.begin

    def get_offset_end(self):
        return self.end

    def get_line_begin(self):
        return self.line_begin

    def get_line_end(self):
        return self.line_end

    def get_cursor(self):
        return self.cursor

    def get_type(self):
        return self.group

    def get_checksum(self):
        return self.checksum
    
    def register_subregion_id(self, child_id):
        self.children.append(child_id)

    def iterate_subregion_ids(self):
        return self.children

class Marker(object):
    class T(object):
        NONE            = 0x00
        COMMENT         = 0x01
        STRING          = 0x02
        PREPROCESSOR    = 0x04
        CODE            = 0x08
        ALL_EXCEPT_CODE = 0x07
        ANY             = 0xFF

        def to_str(self, group):
            if group == self.NONE:
                return "none"
            elif group == self.COMMENT:
                return "comment"
            elif group == self.STRING:
                return "string"
            elif group == self.PREPROCESSOR:
                return "preprocessor"
            elif group == self.CODE:
                return "code"
            else:
                assert(False)
        
    def __init__(self, offset_begin, offset_end, group):
        self.begin = offset_begin
        self.end = offset_end
        self.group = group
        
    def get_offset_begin(self):
        return self.begin

    def get_offset_end(self):
        return self.end

    def get_type(self):
        return self.group

class FileData(LoadableData):
    
    def __init__(self, loader, path, file_id, checksum, content):
        LoadableData.__init__(self, loader, file_id, None)
        self.path = path
        self.checksum = checksum
        self.content = content
        self.regions = None
        self.markers = None
        self.loader = loader
        self.loading_tmp = []
        
    def get_id(self):
        return self.file_id

    def get_path(self):
        return self.path

    def get_checksum(self):
        return self.checksum
    
    def get_content(self):
        return self.content

    def internal_append_region(self, region):
        # here we apply some magic - we rely on special ordering of coming regions,
        # which is supported by code parsers
        prev_id = None
        while True:
            if len(self.loading_tmp) == 0:
                break
            prev_id = self.loading_tmp.pop()
            if self.get_region(prev_id).get_offset_end() > region.get_offset_begin():
                self.loading_tmp.append(prev_id) # return back
                break
        self.loading_tmp.append(region.get_id())
        if prev_id != None:
            self.get_region(prev_id).register_subregion_id(region.get_id())
        self.regions.append(region)

    def load_regions(self):
        if self.regions == None:
            self.regions = []
            for each in self.loader.db.iterate_regions(self.get_id()):
                self.internal_append_region(FileRegionData(self.loader,
                                                   self.get_id(),
                                                   each.region_id,
                                                   each.name,
                                                   each.begin,
                                                   each.end,
                                                   each.line_begin,
                                                   each.line_end,
                                                   each.cursor,
                                                   each.group,
                                                   each.checksum))
                assert(len(self.regions) == each.region_id)
        
    def add_region(self, region_name, offset_begin, offset_end, line_begin, line_end, cursor_line, group, checksum):
        if self.regions == None:
            self.regions = [] # do not load in time of collection
        new_id = len(self.regions) + 1
        self.internal_append_region(FileRegionData(self.loader, self.get_id(), new_id, region_name, offset_begin, offset_end, line_begin, line_end, cursor_line, group, checksum))
        self.loader.db.create_region(self.file_id, new_id, region_name, offset_begin, offset_end, line_begin, line_end, cursor_line, group, checksum)
        return new_id
        
    def get_region(self, region_id):
        self.load_regions()
        return self.regions[region_id - 1]
    
    def get_region_types(self):
        return FileRegionData.T

    def iterate_regions(self, filter_group = FileRegionData.T.ANY):
        self.load_regions()
        for each in self.regions:
            if each.group & filter_group:
                yield each

    def are_regions_loaded(self):
        return self.regions != None

    def load_markers(self):
        if self.markers == None:
            self.markers = []
            for each in self.loader.db.iterate_markers(self.get_id()):
                self.markers.append(Marker(each.begin, each.end, each.group))
        
    def add_marker(self, offset_begin, offset_end, group):
        if self.markers == None:
            self.markers = [] # do not load in time of collection
        self.markers.append(Marker(offset_begin, offset_end, group))
        self.loader.db.create_marker(self.file_id, offset_begin, offset_end, group)
        
    def iterate_markers(self, filter_group = Marker.T.COMMENT |
                         Marker.T.STRING | Marker.T.PREPROCESSOR,
                         region_id = None, exclude_children = True, merge = False):
        self.load_markers()
        
        # merged markers
        if merge == True:
            next_marker = None
            for marker in self.iterate_markers(filter_group, region_id, exclude_children, merge = False):
                if next_marker != None:
                    if next_marker.get_offset_end() == marker.get_offset_begin():
                        # sequential markers
                        next_marker = Marker(next_marker.get_offset_begin(),
                                             marker.get_offset_end(),
                                             next_marker.get_type() | marker.get_type())
                    else:
                        yield next_marker
                        next_marker = None
                if next_marker == None:
                    next_marker = Marker(marker.get_offset_begin(),
                                         marker.get_offset_end(),
                                         marker.get_type())
            if next_marker != None:
                yield next_marker
        
        # all markers per file
        elif region_id == None:
            next_code_marker_start = 0
            for marker in self.markers:
                if Marker.T.CODE & filter_group and next_code_marker_start < marker.get_offset_begin():
                    yield Marker(next_code_marker_start, marker.get_offset_begin(), Marker.T.CODE)
                if marker.group & filter_group:
                    yield marker
                next_code_marker_start = marker.get_offset_end()
            if Marker.T.CODE & filter_group and next_code_marker_start < len(self.get_content()):
                yield Marker(next_code_marker_start, len(self.get_content()), Marker.T.CODE)

        # markers per region
        else:
            region = self.get_region(region_id)
            if region != None:
                
                # code parsers and database know about non-code markers
                # clients want to iterate code as markers as well
                # so, we embed code markers in run-time
                class CodeMarker(Marker):
                    pass
                
                # cache markers for all regions if it does not exist
                if hasattr(region, '_markers_list') == False:
                    # subroutine to populate _markers_list attribute
                    # _markers_list does include code markers
                    def cache_markers_list_rec(data, region_id, marker_start_ind, next_code_marker_start):
                        region = data.get_region(region_id)
                        region._markers_list = []
                        region._first_marker_ind = marker_start_ind
                        #next_code_marker_start = region.get_offset_begin()
                        
                        for sub_id in region.iterate_subregion_ids():
                            subregion = data.get_region(sub_id)
                            # cache all markers before the subregion
                            while len(data.markers) > marker_start_ind and \
                                subregion.get_offset_begin() > data.markers[marker_start_ind].get_offset_begin():
                                    if next_code_marker_start < data.markers[marker_start_ind].get_offset_begin():
                                        # append code markers coming before non-code marker
                                        region._markers_list.append(CodeMarker(next_code_marker_start,
                                                                               data.markers[marker_start_ind].get_offset_begin(),
                                                                               Marker.T.CODE))
                                    next_code_marker_start = data.markers[marker_start_ind].get_offset_end()
                                    region._markers_list.append(marker_start_ind)
                                    marker_start_ind += 1
                                    
                            # cache all code markers before the subregion but after the last marker
                            if next_code_marker_start < subregion.get_offset_begin():
                                region._markers_list.append(CodeMarker(next_code_marker_start,
                                                                       subregion.get_offset_begin(),
                                                                       Marker.T.CODE))
                            next_code_marker_start = subregion.get_offset_begin()
                                
                            # here is the recursive call for all sub-regions
                            (marker_start_ind, next_code_marker_start) = cache_markers_list_rec(data,
                                                                      sub_id,
                                                                      marker_start_ind,
                                                                      next_code_marker_start)
                            
                        # cache all markers after the last subregion
                        while len(data.markers) > marker_start_ind and \
                            region.get_offset_end() > data.markers[marker_start_ind].get_offset_begin():
                                # append code markers coming before non-code marker
                                if next_code_marker_start < data.markers[marker_start_ind].get_offset_begin():
                                    region._markers_list.append(CodeMarker(next_code_marker_start,
                                                                           data.markers[marker_start_ind].get_offset_begin(),
                                                                           Marker.T.CODE))
                                next_code_marker_start = data.markers[marker_start_ind].get_offset_end()
                                region._markers_list.append(marker_start_ind)
                                marker_start_ind += 1
                        
                        # cache the last code segment after the last marker
                        if next_code_marker_start < region.get_offset_end():
                            region._markers_list.append(CodeMarker(next_code_marker_start,
                                                                   region.get_offset_end(),
                                                                   Marker.T.CODE))
                        next_code_marker_start = region.get_offset_end()
                        
                        # return the starting point for the next call of this function
                        return (marker_start_ind, next_code_marker_start)
                    
                    # append markers list to all regions recursively
                    (next_marker_pos, next_code_marker_start) = cache_markers_list_rec(self, 1, 0, 0)
                    assert(next_marker_pos == len(self.markers))
                
                # excluding subregions
                if exclude_children == True:
                    for marker_ind in region._markers_list:
                        if isinstance(marker_ind, int):
                            marker = self.markers[marker_ind]
                        else:
                            marker = marker_ind # CodeMarker
                        if marker.group & filter_group:
                            yield marker
                            
                            
                # including subregions
                else:
                    next_code_marker_start = region.get_offset_begin()
                    for marker in self.markers[region._first_marker_ind:]:
                        if marker.get_offset_begin() >= region.get_offset_end():
                            break
                        if region.get_offset_begin() > marker.get_offset_begin():
                            continue
                        if Marker.T.CODE & filter_group and next_code_marker_start < marker.get_offset_begin():
                            yield Marker(next_code_marker_start, marker.get_offset_begin(), Marker.T.CODE)
                        if marker.group & filter_group:
                            yield marker
                        next_code_marker_start = marker.get_offset_end()
                    if Marker.T.CODE & filter_group and next_code_marker_start < region.get_offset_end():
                        yield Marker(next_code_marker_start, region.get_offset_end(), Marker.T.CODE)

    def get_marker_types(self):
        return Marker.T

    def are_markers_loaded(self):
        return self.markers != None

    def __repr__(self):
        return Data.__repr__(self) + " and regions " + self.regions.__repr__()


class BasePlugin(object):
    
    def initialize(self):
        pass

    def terminate(self):
        pass
    
    def set_name(self, name):
        self.name = name

    def get_name(self):
        if hasattr(self, 'name') == False:
            return None
        return self.name

    def set_version(self, version):
        self.version = version

    def get_version(self):
        if hasattr(self, 'version') == False:
            return None
        return self.version

    def set_plugin_loader(self, loader):
        self.plugin_loader = loader

    def get_plugin_loader(self):
        if hasattr(self, 'plugin_loader') == False:
            return None
        return self.plugin_loader

class Plugin(BasePlugin):

    class Field(object):
        def __init__(self, name, ftype, non_zero=False):
            self.name = name
            self.type = ftype
            self.non_zero = non_zero

    class Property(object):
        def __init__(self, name, value):
            self.name = name
            self.value = value
    
    def initialize(self, namespace=None, support_regions=True, fields=[], properties=[]):
        super(Plugin, self).initialize()
        
        if hasattr(self, 'is_updated') == False:
            self.is_updated = False # original initialization
            
        db_loader = self.get_plugin_loader().get_database_loader()
        
        if namespace == None:
            namespace = self.get_name()

        if (len(fields) != 0 or len(properties) != 0):
            prev_version = db_loader.set_property(self.get_name() + ":version", self.get_version())
            if prev_version != self.get_version():
                self.is_updated = True

        for prop in properties:
            assert(prop.name != 'version')
            prev_prop = db_loader.set_property(self.get_name() + ":" + prop.name, prop.value)
            if prev_prop != prop.value:
                self.is_updated = True

        if len(fields) != 0:
            namespace_obj = db_loader.create_namespace(namespace,
                                                       support_regions=support_regions,
                                                       version=self.get_version())
            for field in fields:
                is_created = namespace_obj.add_field(field.name, field.type, non_zero=field.non_zero)
                assert(is_created != None)
                # if field is created (not cloned from the previous db),
                # mark the plug-in as updated in order to trigger full rescan
                self.is_updated = self.is_updated or is_created

class MetricPlugin(Plugin):
    
    def declare_metric(self, is_active, field,
                       pattern_to_search_or_map_of_patterns,
                       marker_type_mask=Marker.T.ANY,
                       region_type_mask=FileRegionData.T.ANY,
                       exclude_subregions=True,
                       merge_markers=False):
        if hasattr(self, '_fields') == False:
            self._fields = {}
        
        if isinstance(pattern_to_search_or_map_of_patterns, dict):
            map_of_patterns = pattern_to_search_or_map_of_patterns
        else:
            map_of_patterns = {'default': pattern_to_search_or_map_of_patterns}

        if is_active == True:
            self._fields[field.name] = (field,
                                        marker_type_mask,
                                        exclude_subregions,
                                        merge_markers,
                                        map_of_patterns,
                                        region_type_mask)
            
    def is_active(self, metric_name = None):
        if metric_name == None:
            return (len(self._fields.keys()) > 0)
        return (metric_name in self._fields.keys())
    
    def get_fields(self):
        result = []
        for key in self._fields.keys():
            result.append(self._fields[key][0])
        return result
    
    def count_if_active(self, metric_name, data, namespace=None, alias='default'):
        if self.is_active(metric_name) == False:
            return
        
        if namespace == None:
            namespace = self.get_name()
            
        field_data = self._fields[metric_name]
        text = data.get_content()
        # TODO raise exception if alias is bad
        pattern_to_search = field_data[4][alias]
        for region in data.iterate_regions(filter_group=field_data[5]):
            count = 0
            for marker in data.iterate_markers(
                            filter_group = field_data[1],
                            region_id = region.get_id(),
                            exclude_children = field_data[2],
                            merge=field_data[3]):
                count += len(pattern_to_search.findall(text, marker.get_offset_begin(), marker.get_offset_end()))
            region.set_data(namespace, metric_name, count)

class InterfaceNotImplemented(Exception):
    def __init__(self, obj):
        import sys
        Exception.__init__(self, "Method '"
                            + sys._getframe(1).f_code.co_name
                            + "' has not been implemented for "
                            + str(obj.__class__))

class IConfigurable(object):
    def configure(self, options):
        raise InterfaceNotImplemented(self)
    def declare_configuration(self, optparser):
        raise InterfaceNotImplemented(self)

class IRunable(object):
    def run(self, args):
        raise InterfaceNotImplemented(self)
    
class IParser(object):
    def process(self, parent, data, is_updated):
        raise InterfaceNotImplemented(self)

class ICode(object):
    pass

class ITool(object):
    def run(self, tool_args):
        raise InterfaceNotImplemented(self)

class CallbackNotImplemented(Exception):
    
    def __init__(self, obj, callback_name):
        Exception.__init__(self, "Callback '"
                           + callback_name
                           + "' has not been implemented for "
                           + str(obj.__class__))

class Child(object):
    
    def notify(self, parent, callback_name, *args):
        if hasattr(self, callback_name) == False:
            raise CallbackNotImplemented(self, callback_name)
        self.__getattribute__(callback_name)(parent, *args)

    def subscribe_by_parents_name(self, parent_name, callback_name='callback'):
        self.get_plugin_loader().get_plugin(parent_name).subscribe(self, callback_name)
    
    def subscribe_by_parents_interface(self, interface, callback_name='callback'):
        for plugin in self.get_plugin_loader().iterate_plugins():
            if isinstance(plugin, interface):
                plugin.subscribe(self, callback_name)


class Parent(object):
    
    def init_Parent(self):
        if hasattr(self, 'children') == False:
            self.children = []
            
    def subscribe(self, obj, callback_name):
        self.init_Parent()
        if (isinstance(obj, Child) == False):
            raise TypeError()
        self.children.append((obj,callback_name))

    def unsubscribe(self, obj, callback_name):
        self.init_Parent()
        self.children.remove((obj, callback_name))

    def notify_children(self, *args):
        self.init_Parent()
        for child in self.children:
            child[0].notify(self, child[1], *args)

    def iterate_children(self):
        self.init_Parent()
        for child in self.children:
            yield child

# TODO re-factor and remove this
class ExitError(Exception):
    def __init__(self, plugin, reason):
        if plugin != None:
            Exception.__init__(self, "Plugin '"
                               + plugin.get_name()
                               + "' requested abnormal termination: "
                               + reason)
        else:
            Exception.__init__(self, "'Abnormal termination requested: "
                               + reason)