# /**********************************************************************
# *                                                                     *
# * Copyright (c) 2026 Javier Braña <javier.branagutierrez@gmail.com>  *
# *                                                                     *
# * Alignment - Alineamiento horizontal y vertical                      *
# *                                                                     *
# * Define el eje de la carretera mediante:                             *
# *   - Alineamiento horizontal: polilínea + curvas circulares          *
# *   - Alineamiento vertical: rasante con pendientes y curvas verticales*
# *   - Estaciones (progresivas)                                        *
# *                                                                     *
# ***********************************************************************

import FreeCAD
import Part
import math
import numpy as np


def make_alignment_from_wire(wire, name="Alignment"):
    """Crea un objeto Alignment a partir de un wire de FreeCAD."""
    if FreeCAD.ActiveDocument is None:
        return None
    obj = FreeCAD.ActiveDocument.addObject("Part::FeaturePython", name)
    Alignment(obj)
    _ViewProviderAlignment(obj.ViewObject)
    obj.SourceWire = wire
    obj.Label = name
    FreeCAD.ActiveDocument.recompute()
    return obj


class Alignment:
    """
    Alineamiento horizontal + vertical de una carretera.

    Propiedades principales:
      SourceWire         : Polilínea base del eje
      Stations           : Progresivas (lista de distancias)
      StationInterval    : Intervalo entre estaciones
      TotalLength        : Longitud total del eje
      HorizontalCurves   : Curvas circulares (radio, longitud, parámetros)
      VerticalPVI        : Puntos de intersección vertical (PVI) para la rasante
    """

    def __init__(self, obj):
        obj.Proxy = self
        self.setProperties(obj)
        self._cached_chainage = None
        self._cached_station_points = None
        self._cached_tangents = None

    def setProperties(self, obj):
        pl = obj.PropertiesList

        if "SourceWire" not in pl:
            obj.addProperty("App::PropertyLink",
                            "SourceWire", "Alignment",
                            "Polilínea base del eje")

        if "Stations" not in pl:
            obj.addProperty("App::PropertyFloatList",
                            "Stations", "Alignment",
                            "Estaciones (progresivas) en mm")

        if "StationInterval" not in pl:
            obj.addProperty("App::PropertyLength",
                            "StationInterval", "Alignment",
                            "Intervalo entre estaciones").StationInterval = 20000

        if "NumberOfStations" not in pl:
            obj.addProperty("App::PropertyInteger",
                            "NumberOfStations", "Alignment",
                            "Número de estaciones")
        obj.setEditorMode("NumberOfStations", 1)

        if "TotalLength" not in pl:
            obj.addProperty("App::PropertyLength",
                            "TotalLength", "Alignment",
                            "Longitud total del eje")
        obj.setEditorMode("TotalLength", 1)

        if "HorizontalCurveRadii" not in pl:
            obj.addProperty("App::PropertyFloatList",
                            "HorizontalCurveRadii", "Alignment",
                            "Radios de curva en cada vértice (0 = recta)")

        if "ShowStations" not in pl:
            obj.addProperty("App::PropertyBool",
                            "ShowStations", "Alignment",
                            "Mostrar marcas de estación en 3D").ShowStations = False

    def onDocumentRestored(self, obj):
        self.setProperties(obj)

    def execute(self, obj):
        """Calcula estaciones y geometría del alignment."""
        if not obj.SourceWire or not obj.SourceWire.Shape:
            return

        wire = obj.SourceWire.Shape
        if wire.isNull():
            return

        total_len = wire.Length
        obj.TotalLength = total_len
        if total_len <= 0:
            return

        interval = obj.StationInterval.Value
        if interval <= 0:
            interval = 20000

        n_stations = max(2, int(total_len / interval) + 1)
        obj.NumberOfStations = n_stations

        stations = np.linspace(0, total_len, n_stations).tolist()
        obj.Stations = stations

        # Calcular radios de curva en cada vértice del wire
        self._compute_curve_radii(obj, wire)

        # Cache
        self._cached_chainage = stations
        self._cached_station_points = None
        self._cached_tangents = None

    def _compute_curve_radii(self, obj, wire):
        """Calcula el radio de curvatura en cada vértice de la polilínea."""
        vertices = wire.Vertexes
        n = len(vertices)
        if n < 3:
            obj.HorizontalCurveRadii = []
            return

        radii = []
        for i in range(1, n - 1):
            p0 = vertices[i - 1].Point
            p1 = vertices[i].Point
            p2 = vertices[i + 1].Point

            v1 = p1 - p0
            v2 = p2 - p1
            cross = FreeCAD.Vector(0, 0, 1).dot(v1.cross(v2))

            if abs(cross) < 1.0:  # casi colineal
                radii.append(0.0)
            else:
                # Radio aproximado = |v1| * |v2| / |v1 x v2|
                r = v1.Length * v2.Length / abs(cross)
                radii.append(round(r, 0))

        obj.HorizontalCurveRadii = radii

    def get_station_point(self, obj, distance):
        """Devuelve el punto 3D en el eje a una progresiva dada (mm)."""
        if not obj.SourceWire:
            return None
        try:
            wire = obj.SourceWire.Shape
            param = wire.getParameterByLength(distance / obj.TotalLength)
            return wire.valueAt(param)
        except Exception:
            return None

    def get_tangent_at(self, obj, distance):
        """Devuelve el vector tangente en una progresiva (normalizado)."""
        if not obj.SourceWire:
            return None
        try:
            wire = obj.SourceWire.Shape
            param = wire.getParameterByLength(distance / obj.TotalLength)
            t = wire.tangentAt(param)
            if t.Length > 0:
                t.normalize()
            return t
        except Exception:
            return None

    def get_perpendicular_at(self, obj, distance):
        """Devuelve el vector perpendicular (horizontal) en una progresiva."""
        t = self.get_tangent_at(obj, distance)
        if t is None:
            return None
        perp = FreeCAD.Vector(-t.y, t.x, 0)
        perp.normalize()
        return perp

    def get_station_data(self, obj):
        """
        Devuelve arrays de (puntos, tangentes, perpendiculares) para todas las estaciones.

        Returns:
            tuple: (points, tangents, perps) listas de FreeCAD.Vector
        """
        stations = obj.Stations
        if not stations:
            return [], [], []

        points = []
        tangents = []
        perps = []

        for s in stations:
            pt = self.get_station_point(obj, s)
            tg = self.get_tangent_at(obj, s)
            pp = self.get_perpendicular_at(obj, s)
            if pt and tg and pp:
                points.append(pt)
                tangents.append(tg)
                perps.append(pp)

        return points, tangents, perps

    def __getstate__(self):
        return None

    def __setstate__(self, state):
        return None


class _ViewProviderAlignment:
    def __init__(self, vobj):
        vobj.Proxy = self

    def getIcon(self):
        return ""

    def __getstate__(self):
        return None

    def __setstate__(self, state):
        return None