#! python3
# -*- coding: utf-8 -*-
# SPDX-License-Identifier: AGPL-3.0-or-later
# Copyright (C) 2026 Karim Gabriele Varano
"""
treppe_grips.py
Display-Conduit fuer gruene Endpunkt-Marker an Treppen-Achsen. Visuelle
Indikation wie bei Waenden, aber keine eigene Drag-Logik — der normale
Partnership-Cascade (elemente._on_select_objects) + Pure-Transform-Pfad
verschieben die Treppe bereits sauber.

Endpunkt-Logik pro Treppen-Art:
  - gerade  : PointAtStart, PointAtEnd der Linie
  - L       : poly[0] (Start), poly[2] (Ende) — poly[1] ist der Eck-Punkt
  - Wendel  : poly[1] (Start), poly[2] (Ende) — poly[0] ist Rotations-
              zentrum, nicht der Treppen-Anfang
"""
import Rhino
import Rhino.Display as rd
import Rhino.Geometry as rg
import scriptcontext as sc
import System.Drawing as SD


_MARKER_RADIUS_PX = 7
_MARKER_FILL   = SD.Color.FromArgb(220, 95, 168, 150)  # petrol-gruen, gleich wie wand_grips
_MARKER_BORDER = SD.Color.FromArgb(255, 47, 93, 84)


def _treppe_endpoints(axis_obj):
    """Liefert Liste von Point3d fuer Treppen-Start + -Ende. Beachtet
    treppe_art (Wendel hat anderes Polyline-Schema)."""
    if axis_obj is None or axis_obj.IsDeleted: return []
    a = axis_obj.Attributes
    if a.GetUserString("dossier_element_type") != "treppe_axis": return []
    geom = axis_obj.Geometry
    if not isinstance(geom, rg.Curve): return []
    art = a.GetUserString("dossier_treppe_art") or "gerade"
    try:
        if art == "wendel":
            ok, poly = geom.TryGetPolyline()
            if not ok or poly is None or poly.Count != 3: return []
            return [poly[1], poly[2]]
        # gerade + L → Start- und End-Punkt der Curve sind die Treppen-Enden
        return [geom.PointAtStart, geom.PointAtEnd]
    except Exception:
        return []


class _TreppeEndpointConduit(rd.DisplayConduit):
    """Zeichnet gruene Endpunkt-Marker an allen selektierten Treppen-Achsen."""

    def DrawForeground(self, e):
        try:
            doc = Rhino.RhinoDoc.ActiveDoc
            if doc is None: return
            sel = list(doc.Objects.GetSelectedObjects(False, False))
            seen = set()
            for obj in sel:
                a = obj.Attributes
                eid = a.GetUserString("dossier_element_id") or ""
                if not eid or eid in seen: continue
                # Source-Axis via element_id finden (kann anderer Obj sein
                # wenn User nur Volume oder 2D-Symbol selektiert hat)
                axis = None
                for o in doc.Objects:
                    if o is None or o.IsDeleted: continue
                    try:
                        a2 = o.Attributes
                        if a2.GetUserString("dossier_element_id") == eid and \
                           a2.GetUserString("dossier_element_type") == "treppe_axis":
                            axis = o; break
                    except Exception: continue
                if axis is None: continue
                seen.add(eid)
                for pt in _treppe_endpoints(axis):
                    try:
                        e.Display.DrawPoint(pt,
                            rd.PointStyle.RoundControlPoint,
                            _MARKER_RADIUS_PX, _MARKER_FILL)
                    except Exception:
                        try: e.Display.DrawDot(pt, "●", _MARKER_FILL, _MARKER_BORDER)
                        except Exception: pass
        except Exception as ex:
            print("[TREPPE_GRIPS] DrawForeground:", ex)


_STICKY_CONDUIT = "_dossier_treppe_grips_conduit"


def install_handlers():
    """Idempotente Registrierung. Bei Modul-Reload alten Conduit zuerst
    disablen, dann neuen anhaengen."""
    try:
        old = sc.sticky.get(_STICKY_CONDUIT)
        if old is not None:
            try: old.Enabled = False
            except Exception: pass
        conduit = _TreppeEndpointConduit()
        conduit.Enabled = True
        sc.sticky[_STICKY_CONDUIT] = conduit
        print("[TREPPE_GRIPS] Endpoint-Conduit aktiv")
    except Exception as ex:
        print("[TREPPE_GRIPS] install:", ex)