# SPDX-License-Identifier: GPL-2.0-or-later
import bpy
from bpy.types import Menu, Panel, UIList
from rna_prop_ui import PropertyPanel


class DataButtonsPanel:
    bl_space_type = 'PROPERTIES'
    bl_region_type = 'WINDOW'
    bl_context = "data"

    @classmethod
    def poll(cls, context):
        engine = context.scene.render.engine
        return hasattr(context, 'pointcloud') and context.pointcloud and (engine in cls.COMPAT_ENGINES)


class DATA_PT_context_pointcloud(DataButtonsPanel, Panel):
    bl_label = ""
    bl_options = {'HIDE_HEADER'}
    COMPAT_ENGINES = {'BLENDER_RENDER', 'BLENDER_EEVEE', 'BLENDER_EEVEE_NEXT', 'BLENDER_WORKBENCH'}

    def draw(self, context):
        layout = self.layout

        ob = context.object
        pointcloud = context.pointcloud
        space = context.space_data

        if ob:
            layout.template_ID(ob, "data")
        elif pointcloud:
            layout.template_ID(space, "pin_id")


class POINTCLOUD_MT_add_attribute(Menu):
    bl_label = "Add Attribute"

    @staticmethod
    def add_standard_attribute(layout, pointcloud, name, data_type, domain):
        exists = pointcloud.attributes.get(name) is not None

        col = layout.column()
        col.enabled = not exists
        col.operator_context = 'EXEC_DEFAULT'

        props = col.operator("geometry.attribute_add", text=name)
        props.name = name
        props.data_type = data_type
        props.domain = domain

    def draw(self, context):
        layout = self.layout
        pointcloud = context.pointcloud

        self.add_standard_attribute(layout, pointcloud, 'radius', 'FLOAT', 'POINT')
        self.add_standard_attribute(layout, pointcloud, 'color', 'FLOAT_COLOR', 'POINT')
        self.add_standard_attribute(layout, pointcloud, 'id', 'INT', 'POINT')
        self.add_standard_attribute(layout, pointcloud, 'velocity', 'FLOAT_VECTOR', 'POINT')

        layout.separator()

        layout.operator_context = 'INVOKE_DEFAULT'
        layout.operator("geometry.attribute_add", text="Custom...")


class POINTCLOUD_UL_attributes(UIList):
    def filter_items(self, _context, data, property):
        attributes = getattr(data, property)
        flags = []
        indices = [i for i in range(len(attributes))]

        for item in attributes:
            flags.append(self.bitflag_filter_item if item.is_internal else 0)

        return flags, indices

    def draw_item(self, _context, layout, _data, attribute, _icon, _active_data, _active_propname, _index):
        data_type = attribute.bl_rna.properties['data_type'].enum_items[attribute.data_type]

        split = layout.split(factor=0.75)
        split.emboss = 'NONE'
        split.prop(attribute, "name", text="")
        sub = split.row()
        sub.alignment = 'RIGHT'
        sub.active = False
        sub.label(text=data_type.name)


class DATA_PT_pointcloud_attributes(DataButtonsPanel, Panel):
    bl_label = "Attributes"
    COMPAT_ENGINES = {'BLENDER_RENDER', 'BLENDER_EEVEE', 'BLENDER_EEVEE_NEXT', 'BLENDER_WORKBENCH'}

    def draw(self, context):
        pointcloud = context.pointcloud

        layout = self.layout
        row = layout.row()

        col = row.column()
        col.template_list(
            "POINTCLOUD_UL_attributes",
            "attributes",
            pointcloud,
            "attributes",
            pointcloud.attributes,
            "active_index",
            rows=3,
        )

        col = row.column(align=True)
        col.menu("POINTCLOUD_MT_add_attribute", icon='ADD', text="")
        col.operator("geometry.attribute_remove", icon='REMOVE', text="")


class DATA_PT_custom_props_pointcloud(DataButtonsPanel, PropertyPanel, Panel):
    COMPAT_ENGINES = {'BLENDER_RENDER', 'BLENDER_EEVEE', 'BLENDER_EEVEE_NEXT', 'BLENDER_WORKBENCH'}
    _context_path = "object.data"
    _property_type = bpy.types.PointCloud if hasattr(bpy.types, "PointCloud") else None


classes = (
    DATA_PT_context_pointcloud,
    DATA_PT_pointcloud_attributes,
    DATA_PT_custom_props_pointcloud,
    POINTCLOUD_MT_add_attribute,
    POINTCLOUD_UL_attributes,
)

if __name__ == "__main__":  # only for live edit.
    from bpy.utils import register_class
    for cls in classes:
        register_class(cls)