import bpy
from bpy.props import (StringProperty, BoolProperty, PointerProperty)
from bpy_types import (PropertyGroup)
from ..propGroups.conversions_from_prop_group import property_group_value_to_custom_property_value
from ..propGroups.conversions_to_prop_group import property_group_value_from_custom_property_value

class ComponentMetadata(bpy.types.PropertyGroup):
    name : bpy.props.StringProperty(
        name = "name",
        default = ""
    )

    long_name : bpy.props.StringProperty(
        name = "long name",
        default = ""
    )

    type_name : bpy.props.StringProperty(
        name = "Type",
        default = ""
    )

    values: bpy.props.StringProperty(
        name = "Value",
        default = ""
    )

    enabled: BoolProperty(
        name="enabled",
        description="component enabled",
        default=True
    )

    invalid: BoolProperty(
        name="invalid",
        description="component is invalid, because of missing registration/ other issues",
        default=False
    )

    invalid_details: StringProperty(
        name="invalid details",
        description="detailed information about why the component is invalid",
        default=""
    )

    visible: BoolProperty( # REALLY dislike doing this for UI control, but ok hack for now
        default=True
    )

class ComponentsMeta(PropertyGroup):
    infos_per_component:  StringProperty(
        name="infos per component",
        description="component"
    )
    components: bpy.props.CollectionProperty(type = ComponentMetadata)  

    @classmethod
    def register(cls):
        bpy.types.Object.components_meta = PointerProperty(type=ComponentsMeta)

    @classmethod
    def unregister(cls):
        del bpy.types.Object.components_meta

# We need a collection property of components PER object
def get_component_metadata_by_short_name(object, short_name):
    if not "components_meta" in object:
        return None
    return next(filter(lambda component: component["name"] == short_name, object.components_meta.components), None)

# remove no longer valid metadata from object
def cleanup_invalid_metadata(object):
    components_metadata = object.components_meta.components
    to_remove = []
    for index, component_meta in enumerate(components_metadata):
        short_name = component_meta.name
        if short_name not in object.keys():
            print("component:", short_name, "present in metadata, but not in object")
            to_remove.append(index)
    for index in to_remove:
        components_metadata.remove(index)


# returns a component definition ( an entry in registry's type_infos) with matching short name or None if nothing has been found
def find_component_definition_from_short_name(short_name):
    registry = bpy.context.window_manager.components_registry
    long_name = registry.short_names_to_long_names.get(short_name, None)
    if long_name != None:
        return registry.type_infos.get(long_name, None)
    return None

# FIXME: feels a bit heavy duty, should only be done
# if the components panel is active ?
def ensure_metadata_for_all_objects():
    for object in bpy.data.objects:
        add_metadata_to_components_without_metadata(object)

# returns whether an object has custom properties without matching metadata
def do_object_custom_properties_have_missing_metadata(object):
    components_metadata = getattr(object, "components_meta", None)
    if components_metadata == None:
        return True

    components_metadata = components_metadata.components

    missing_metadata = False
    for component_name in dict(object) :
        if component_name == "components_meta":
            continue
        component_meta =  next(filter(lambda component: component["name"] == component_name, components_metadata), None)
        if component_meta == None: 
            # current component has no metadata but is there even a compatible type in the registry ?
            # if not ignore it
            component_definition = find_component_definition_from_short_name(component_name)
            if component_definition != None:
                missing_metadata = True
                break

    return missing_metadata


# adds metadata to object only if it is missing
def add_metadata_to_components_without_metadata(object):
    registry = bpy.context.window_manager.components_registry

    for component_name in dict(object) :
        if component_name == "components_meta":
            continue
        upsert_component_in_object(object, component_name, registry)
       
# adds a component to an object (including metadata) using the provided component definition & optional value
def add_component_to_object(object, component_definition, value=None):
    cleanup_invalid_metadata(object)
    if object is not None:
        # print("add_component_to_object", component_definition)
        long_name = component_definition["title"]
        short_name = component_definition["short_name"]
        registry = bpy.context.window_manager.components_registry
        if not registry.has_type_infos():
            raise Exception('registry type infos have not been loaded yet or are missing !')
        definition = registry.type_infos[long_name]
        # now we use our pre_generated property groups to set the initial value of our custom property
        (_, propertyGroup) = upsert_component_in_object(object, component_name=short_name, registry=registry)
        if value == None:
            value = property_group_value_to_custom_property_value(propertyGroup, definition, registry, None)
        else: # we have provided a value, that is a raw , custom property value, to set the value of the propertyGroup
            object["__disable__update"] = True # disable update callback while we set the values of the propertyGroup "tree" (as a propertyGroup can contain other propertyGroups) 
            property_group_value_from_custom_property_value(propertyGroup, definition, registry, value)
            del object["__disable__update"]

        object[short_name] = value
       
def upsert_component_in_object(object, component_name, registry):
    # print("upsert_component_in_object", object, "component name", component_name)
    # TODO: upsert this part too ?
    target_components_metadata = object.components_meta.components
    component_definition = find_component_definition_from_short_name(component_name)
    if component_definition != None:
        short_name = component_definition["short_name"]
        long_name = component_definition["title"]
        property_group_name = registry.get_propertyGroupName_from_shortName(short_name)
        propertyGroup = None

        component_meta = next(filter(lambda component: component["name"] == short_name, target_components_metadata), None)
        if not component_meta:
            component_meta = target_components_metadata.add()
            component_meta.name = short_name
            component_meta.long_name = long_name
            propertyGroup = getattr(component_meta, property_group_name, None)
        else: # this one has metadata but we check that the relevant property group is present
            propertyGroup = getattr(component_meta, property_group_name, None)

        # try to inject propertyGroup if not present
        if propertyGroup == None:
            #print("propertygroup not found in metadata attempting to inject")
            if property_group_name in registry.component_propertyGroups:
                # we have found a matching property_group, so try to inject it
                # now inject property group
                setattr(ComponentMetadata, property_group_name, registry.component_propertyGroups[property_group_name]) # FIXME: not ideal as all ComponentMetadata get the propGroup, but have not found a way to assign it per instance
                propertyGroup = getattr(component_meta, property_group_name, None)
        
        # now deal with property groups details
        if propertyGroup != None:
            if short_name in registry.invalid_components:
                component_meta.enabled = False
                component_meta.invalid = True
                component_meta.invalid_details = "component contains fields that are not in the schema, disabling"
        else:
            # if we still have not found the property group, mark it as invalid
            component_meta.enabled = False
            component_meta.invalid = True
            component_meta.invalid_details = "component not present in the schema, possibly renamed? Disabling for now"
        # property_group_value_from_custom_property_value(propertyGroup, component_definition, registry, object[component_name])

        return (component_meta, propertyGroup)
    else:
        return(None, None)


def copy_propertyGroup_values_to_another_object(source_object, target_object, component_name, registry):
    if source_object == None or target_object == None or component_name == None:
        raise Exception('missing input data, cannot copy component propertryGroup')
    
    component_definition = find_component_definition_from_short_name(component_name)
    short_name = component_definition["short_name"]
    property_group_name = registry.get_propertyGroupName_from_shortName(short_name)

    registry = bpy.context.window_manager.components_registry

    source_components_metadata = source_object.components_meta.components
    source_componentMeta = next(filter(lambda component: component["name"] == short_name, source_components_metadata), None)
    # matching component means we already have this type of component 
    source_propertyGroup = getattr(source_componentMeta, property_group_name)

    # now deal with the target object
    (_, target_propertyGroup) = upsert_component_in_object(target_object, component_name, registry)
    # add to object
    value = property_group_value_to_custom_property_value(target_propertyGroup, component_definition, registry, None)
    target_object[short_name] = value

    # copy the values over 
    for field_name in source_propertyGroup.field_names:
        if field_name in source_propertyGroup:
            target_propertyGroup[field_name] = source_propertyGroup[field_name]
    apply_propertyGroup_values_to_object_customProperties(target_object)

# TODO: move to propgroups ?
def apply_propertyGroup_values_to_object_customProperties(object):
    cleanup_invalid_metadata(object)
    registry = bpy.context.window_manager.components_registry
    for component_name in dict(object) :
        if component_name == "components_meta":
            continue
        (_, propertyGroup) =  upsert_component_in_object(object, component_name, registry)
        component_definition = find_component_definition_from_short_name(component_name)
        if component_definition != None:
            value = property_group_value_to_custom_property_value(propertyGroup, component_definition, registry, None)
            object[component_name] = value



def apply_customProperty_values_to_object_propertyGroups(object):
    print("apply custom properties to ", object.name)
    registry = bpy.context.window_manager.components_registry
    for component_name in dict(object) :
        if component_name == "components_meta":
            continue
        component_definition = find_component_definition_from_short_name(component_name)
        if component_definition != None:
            property_group_name = registry.get_propertyGroupName_from_shortName(component_name)
            components_metadata = object.components_meta.components
            source_componentMeta = next(filter(lambda component: component["name"] == component_name, components_metadata), None)
            # matching component means we already have this type of component 
            propertyGroup = getattr(source_componentMeta, property_group_name, None)
            customProperty_value = object[component_name]
            #value = property_group_value_to_custom_property_value(propertyGroup, component_definition, registry, None)
            
            object["__disable__update"] = True # disable update callback while we set the values of the propertyGroup "tree" (as a propertyGroup can contain other propertyGroups) 
            property_group_value_from_custom_property_value(propertyGroup, component_definition, registry, customProperty_value)
            del object["__disable__update"]

# removes the given component from the object: removes both the custom property and the matching metadata from the object
def remove_component_from_object(object, component_name):
    del object[component_name]

    components_metadata = getattr(object, "components_meta", None)
    if components_metadata == None:
        return False
    
    components_metadata = components_metadata.components
    to_remove = []
    for index, component_meta in enumerate(components_metadata):
        short_name = component_meta.name
        if short_name == component_name:
            to_remove.append(index)
            break
    for index in to_remove:
        components_metadata.remove(index)
    return True