# registry.py
import bpy
from typing import Any, Callable

_bpy_class_registry: list[type] = []
_timer_registry: list[Callable[..., int | None]] = []

# BPY CLASSES
def register_class(cls: type) -> type:
    if cls not in _bpy_class_registry:
        _bpy_class_registry.append(cls)
    return cls

def get() -> list[type]:
    return list(_bpy_class_registry)

def get_label_by_name(name: str) -> str:
    for cls in get():
        if cls.__name__ == name:
            return getattr(cls, "bl_label", "No Label")
    return ''

def get_class_by_name(name: str) -> type | None:
    for cls in get():
        if cls.__name__ == name:
            return cls
    return None

def blender_register_classes():
    for cls in _bpy_class_registry:
        try:
            bpy.utils.register_class(cls)
        except Exception as e:
            print(f"Nodeslicer: Failed to register {cls}: {e}")

def blender_unregister_classes():
    for cls in reversed(_bpy_class_registry):
        try:
            if hasattr(cls, "is_registered") and cls.is_registered: # type: ignore
                 bpy.utils.unregister_class(cls)
            elif hasattr(cls, "bl_rna"):
                 # Fallback for classes that don't have is_registered (older Blender or certain types)
                 bpy.utils.unregister_class(cls)
        except Exception as e:
            print(f"Nodeslicer: Failed to unregister {cls}: {e}")

# TIMERS
def register_timer(clb: Callable[..., Any]):
    _timer_registry.append(clb)
    return clb

def get_timers() -> list[Callable[..., int | None]]:
    return list(_timer_registry)

def blender_register_timers():
    for timer in _timer_registry:
        bpy.app.timers.register(timer, persistent=True)

def blender_unregister_timers():
    for timer in _timer_registry:
        bpy.app.timers.unregister(timer)

import os

from bpy.utils.previews import ImagePreviewCollection
_icons_pcoll: ImagePreviewCollection | None = None

def blender_register_icons():
    global _icons_pcoll

    _icons_pcoll = bpy.utils.previews.new()

    my_icons_dir = os.path.join(os.path.dirname(__file__), "icons")
    for filename in os.listdir(my_icons_dir):
        _icons_pcoll.load(filename, os.path.join(my_icons_dir, filename), 'IMAGE')

def blender_unregister_icons():
    global _icons_pcoll
    
    if not _icons_pcoll: return
    bpy.utils.previews.remove(_icons_pcoll)
    del _icons_pcoll

def get_icon(icon_id: str) -> int:
    global _icons_pcoll

    if not _icons_pcoll: return -1
    return _icons_pcoll[icon_id].icon_id