# SPDX-License-Identifier: LGPL-2.1-or-later

# ***************************************************************************
# *   Copyright (c) 2009, 2010 Yorik van Havre <yorik@uncreated.net>        *
# *   Copyright (c) 2009, 2010 Ken Cline <cline@frii.com>                   *
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# *   This file is part of the FreeCAD CAx development system.              *
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# *   USA                                                                   *
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"""Provides various functions for general geometrical calculations."""
## @package geometry
# \ingroup draftgeoutils
# \brief Provides various functions for general geometrical calculations.

import math
import lazy_loader.lazy_loader as lz

import FreeCAD as App
import DraftVecUtils

import draftutils.gui_utils as gui_utils

from draftgeoutils.general import geomType, vec

# Delay import of module until first use because it is heavy
Part = lz.LazyLoader("Part", globals(), "Part")

## \addtogroup draftgeoutils
# @{


def findPerpendicular(point, edgeslist, force=None):
    """Find the perpendicular distance between a point and a list of edges.

    If force is specified, only the edge[force] will be considered,
    and it will be considered infinite.

    Returns
    -------
    [vector_from_point_to_closest_edge, edge_index]
        The vector and the index in the list.

    None
        If no perpendicular vector could be found.
    """
    if not isinstance(edgeslist, list):
        try:
            edgeslist = edgeslist.Edges
        except AttributeError:
            print("Doesn't have 'Edges'")
            return None

    if force is None:
        valid = None
        for edge in edgeslist:
            dist = findDistance(point, edge, strict=True)
            if dist:
                if not valid:
                    valid = [dist, edgeslist.index(edge)]
                else:
                    if dist.Length < valid[0].Length:
                        valid = [dist, edgeslist.index(edge)]
        return valid
    else:
        edge = edgeslist[force]
        dist = findDistance(point, edge)
        if dist:
            return [dist, force]
        else:
            return None
        return None


def findDistance(point, edge, strict=False):
    """Return a vector from the point to its closest point on the edge.

    If `strict` is `True`, the vector will be returned
    only if its endpoint lies on the `edge`.
    Edge can also be a list of 2 points.
    """
    if isinstance(point, App.Vector):
        if isinstance(edge, list):
            segment = edge[1].sub(edge[0])
            chord = edge[0].sub(point)
            norm = segment.cross(chord)
            perp = segment.cross(norm)
            dist = DraftVecUtils.project(chord, perp)

            if not dist:
                return None

            newpoint = point.add(dist)

            if dist.Length == 0:
                return None

            if strict:
                s1 = newpoint.sub(edge[0])
                s2 = newpoint.sub(edge[1])
                if s1.Length <= segment.Length and s2.Length <= segment.Length:
                    return dist
                else:
                    return None
            else:
                return dist

        elif geomType(edge) == "Line":
            segment = vec(edge)
            chord = edge.Vertexes[0].Point.sub(point)
            norm = segment.cross(chord)
            perp = segment.cross(norm)
            dist = DraftVecUtils.project(chord, perp)

            if not dist:
                return None

            newpoint = point.add(dist)

            if dist.Length == 0:
                return None

            if strict:
                s1 = newpoint.sub(edge.Vertexes[0].Point)
                s2 = newpoint.sub(edge.Vertexes[-1].Point)
                if s1.Length <= segment.Length and s2.Length <= segment.Length:
                    return dist
                else:
                    return None
            else:
                return dist

        elif geomType(edge) == "Circle":
            ve1 = edge.Vertexes[0].Point
            if len(edge.Vertexes) > 1:
                ve2 = edge.Vertexes[-1].Point
            else:
                ve2 = None
            center = edge.Curve.Center
            segment = center.sub(point)

            if segment.Length == 0:
                return None

            ratio = (segment.Length - edge.Curve.Radius) / segment.Length
            dist = segment.multiply(ratio)
            newpoint = App.Vector.add(point, dist)

            if dist.Length == 0:
                return None

            if strict and ve2:
                # Note 1: DraftVecUtils.angle(App.Vector(1, 1, 0)) => -0.7854
                # Note 2: Angles are in the +pi to -pi range.
                ang1 = DraftVecUtils.angle(ve1.sub(center))
                ang2 = DraftVecUtils.angle(ve2.sub(center))
                angpt = DraftVecUtils.angle(newpoint.sub(center))
                if ang1 >= ang2:  # Arc does not cross the 9 o'clock point.
                    if ang1 >= angpt and angpt >= ang2:
                        return dist
                    else:
                        return None
                elif ang1 >= angpt or angpt >= ang2:
                    return dist
                else:
                    return None
            else:
                return dist

        elif geomType(edge) == "BSplineCurve" or geomType(edge) == "BezierCurve":
            try:
                pr = edge.Curve.parameter(point)
                np = edge.Curve.value(pr)
                dist = np.sub(point)
            except Part.OCCError:
                print("DraftGeomUtils: Unable to get curve parameter " "for point ", point)
                return None
            else:
                return dist
        else:
            print("DraftGeomUtils: Couldn't project point")
            return None
    else:
        print("DraftGeomUtils: Couldn't project point")
        return None


def get_spline_normal(edge, tol=-1):
    """Find the normal of a BSpline edge."""

    if edge.isNull():
        return None

    if is_straight_line(shape, tol):
        return None

    plane = edge.findPlane(tol)
    if plane:
        normal = plane.Axis
        return normal
    else:
        return None


def get_shape_normal(shape):
    """Find the normal of a shape or list of points or colinear edges, if possible."""

    # New function based on get_normal() drafted by @Roy_043
    # in discussion https://forum.freecad.org/viewtopic.php?p=717862#p717862
    #
    # The normal would not be affected  by the 3D view direction and flipped as
    # get_normal would be. Placement of the Shape is taken into account in this
    # new function instead :
    # - Normal of a planar shape is usually bi-directional, this function return
    #   the one 'in the direction' of the shape's placement 'normal' (z-direction).
    #   As reference, shape.findPlane() favour positive axes, get_normal()
    #   favour the 'view direction' (obtained by getViewDirection() ).
    # - Even when the Shape is an edge or colinear edges, its Placement is taken
    #   into account, and this function return one 'in the direction' of the
    #   shape's placement 'normal' (z-direction).
    #   https://forum.freecad.org/viewtopic.php?p=715850#p715850
    # The normal direction of a Draft wire (co-planar) or arc used to depends on
    # the way the shape is constructed i.e. by vertexes in clockwise or
    # anti-clockwise.  This cryptic behaviour no longer matters.

    if shape.isNull():
        return None

    # Roy_043's remarks on the behavior of Shape.findPlane():
    # - https://forum.freecad.org/viewtopic.php?p=713993#p713993
    # Check if the shape is planar
    # If True: check if the outer wire is closed:
    #    if True  :   Return a (plane with) normal based on the direction of the outer wire (CW or CCW).
    #    if False : ? Return a (plane with) normal that points towards positive global axes with a certain priority
    #                 (probably? Z, Y and then X).
    # If False: return None.
    #
    # Further remarks :
    # - Tested Sketch with 2 colinear edges return a Plane with Axis
    # - Tested Sketch with 1 edge return no Plane with no Axis

    shape_rot = shape.Placement.Rotation
    plane = shape.findPlane()

    if plane is None:
        if not is_straight_line(shape):
            return None
        start_edge = shape.Edges[0]
        x_vec = start_edge.tangentAt(
            start_edge.FirstParameter
        )  # Return vector is in global coordinate
        local_x_vec = shape_rot.inverted().multVec(x_vec)  #
        local_rot = App.Rotation(local_x_vec, App.Vector(0, 1, 0), App.Vector(0, 0, 1), "XZY")
        # see https://blog.freecad.org/2023/01/16/the-rotation-api-in-freecad/ for App.Rotation(vecx, vecy, vecz, string)
        # discussion - https://forum.freecad.org/viewtopic.php?p=717738#p717738
        return shape_rot.multiply(local_rot).multVec(App.Vector(0, 0, 1))

    normal = plane.Axis
    shape_normal = shape_rot.multVec(App.Vector(0, 0, 1))
    # Now, check the normal direction of the plane (plane.Axis).
    # The final deduced normal should be 'in the direction' of the z-direction of the shape's placement,
    # if plane.Axis is in the 'opposite' direction of the Z direction of the shape's placement, reverse it.
    if normal.getAngle(shape_normal) > math.pi / 2:
        normal = normal.negative()
    return normal


def get_normal(shape, tol=-1):
    """Find the normal of a shape or list of points, if possible."""

    # for points
    if isinstance(shape, (list, tuple)):
        if len(shape) <= 2:
            return None
        else:
            poly = Part.makePolygon(shape)
            if is_straight_line(poly, tol):
                return None

            plane = poly.findPlane(tol)
            if plane:
                normal = plane.Axis
                return normal
            else:
                return None

    # for shapes
    if shape.isNull():
        return None

    if is_straight_line(shape, tol):
        return None
    else:
        plane = find_plane(shape, tol)
        if plane:
            normal = plane.Axis
        else:
            return None

    # Check the 3D view to flip the normal if the GUI is available
    if App.GuiUp:
        view = gui_utils.get_3d_view()
        if view is not None:
            v_dir = view.getViewDirection()
            if normal.getAngle(v_dir) < 0.78:
                normal = normal.negative()

    return normal


def getRotation(v1, v2=App.Vector(0, 0, 1)):
    """Get the rotation Quaternion between 2 vectors."""
    if (v1.dot(v2) > 0.999999) or (v1.dot(v2) < -0.999999):
        # vectors are opposite
        return None

    axis = v1.cross(v2)
    axis.normalize()
    # angle = math.degrees(math.sqrt(v1.Length^2 * v2.Length^2) + v1.dot(v2))
    angle = math.degrees(DraftVecUtils.angle(v1, v2, axis))
    return App.Rotation(axis, angle)


def is_planar(shape, tol=-1):
    """Return True if the given shape or list of points is planar."""

    # for points
    if isinstance(shape, list):
        if len(shape) <= 3:
            return True
        else:
            poly = Part.makePolygon(shape)
            if is_straight_line(poly, tol):
                return True

            plane = poly.findPlane(tol)
            if plane:
                return True
            else:
                return False

    # for shapes
    if shape.isNull():
        return False

    # because Part.Shape.findPlane return None for Vertex and straight edges
    if shape.ShapeType == "Vertex":
        return True

    if is_straight_line(shape, tol):
        return True

    plane = find_plane(shape, tol)
    if plane:
        return True
    else:
        return False


def is_straight_line(shape, tol=-1):
    """Return True if shape is a straight line.
    function used in other methods because Part.Shape.findPlane assign a
    plane and normal to straight wires creating privileged directions
    and to deal with straight wires with overlapped edges."""

    if shape.isNull():
        return False

    if len(shape.Faces) != 0:
        return False

    if len(shape.Edges) == 0:
        return False

    if len(shape.Edges) >= 1:
        start_edge = shape.Edges[0]
        dir_start_edge = start_edge.tangentAt(start_edge.FirstParameter)
        point_start_edge = start_edge.firstVertex().Point

        # set tolerance
        if tol <= 0:
            err = shape.globalTolerance(tol)
        else:
            err = tol

        for edge in shape.Edges:
            first_point = edge.firstVertex().Point
            last_point = edge.lastVertex().Point
            dir_edge = edge.tangentAt(edge.FirstParameter)
            # check if edge is curve or no parallel to start_edge
            # because sin(x) = x + O(x**3), for small angular deflection it's
            # enough use the cross product of directions (or dot with a normal)
            if (
                abs(edge.Length - first_point.distanceToPoint(last_point)) > err
                # https://forum.freecad.org/viewtopic.php?p=726101#p726101
                # Shape with parallel edges but not colinear used to return True
                # by this function, below line added fixes this bug.
                # Further remark on the below fix :
                # - get_normal() use this function, may had created problems
                #   previously but not reported; on the other hand, this fix
                #   seems have no 'regression' created as get_normal use
                #   plane.Axis (with 3DView check).  See get_shape_normal()
                #   which take into account shape's placement
                # - other functions had been using this also : Keep In View to
                #    see if there is 'regression' :
                #
                # $ grep -rni "is_straight" ./
                # ./draftfunctions/upgrade.py
                # ./draftgeoutils/geometry.py
                # ./draftmake/make_wire.py
                or first_point.distanceToLine(point_start_edge, dir_start_edge) > err  #
                or dir_start_edge.cross(dir_edge).Length > err
            ):
                return False

    return True


def are_coplanar(shape_a, shape_b, tol=-1):
    """Return True if exist a plane containing both shapes."""

    if shape_a.isNull() or shape_b.isNull():
        return False

    if not is_planar(shape_a, tol) or not is_planar(shape_b, tol):
        return False

    if shape_a.isEqual(shape_b):
        return True

    plane_a = find_plane(shape_a, tol)
    plane_b = find_plane(shape_b, tol)

    # set tolerance
    if tol <= 0:
        err = 1e-7
    else:
        err = tol

    if plane_a and plane_b:
        normal_a = plane_a.Axis
        normal_b = plane_b.Axis
        proj = plane_a.projectPoint(plane_b.Position)
        if normal_a.cross(normal_b).Length > err or plane_b.Position.sub(proj).Length > err:
            return False
        else:
            return True

    elif plane_a and not plane_b:
        normal_a = plane_a.Axis
        for vertex in shape_b.Vertexes:
            dir_ver_b = vertex.Point.sub(plane_a.Position).normalize()
            if abs(normal_a.dot(dir_ver_b)) > err:
                proj = plane_a.projectPoint(vertex.Point)
                if vertex.Point.sub(proj).Length > err:
                    return False
        return True

    elif plane_b and not plane_a:
        normal_b = plane_b.Axis
        for vertex in shape_a.Vertexes:
            dir_ver_a = vertex.Point.sub(plane_b.Position).normalize()
            if abs(normal_b.dot(dir_ver_a)) > err:
                proj = plane_b.projectPoint(vertex.Point)
                if vertex.Point.sub(proj).Length > err:
                    return False
        return True
    # not normal_a and not normal_b:
    else:
        points_a = [vertex.Point for vertex in shape_a.Vertexes]
        points_b = [vertex.Point for vertex in shape_b.Vertexes]
        poly = Part.makePolygon(points_a + points_b)
        if is_planar(poly, tol):
            return True
        else:
            return False


def get_spline_surface_normal(shape, tol=-1):
    """Check if shape formed by BSpline surfaces is planar and get normal.
    If shape is not planar return None."""

    if shape.isNull():
        return None

    if len(shape.Faces) == 0:
        return None

    # set tolerance
    if tol <= 0:
        err = shape.globalTolerance(tol)
    else:
        err = tol

    first_surf = shape.Faces[0].Surface

    if not first_surf.isPlanar(tol):
        return None

    # find bounds of first_surf
    u0, u1, v0, v1 = first_surf.bounds()
    u = (u0 + u1) / 2
    v = (v0 + v1) / 2
    first_normal = first_surf.normal(u, v)
    # check if all faces are planar and parallel
    for face in shape.Faces:
        surf = face.Surface
        if not surf.isPlanar(tol):
            return None
        u0, u1, v0, v1 = surf.bounds()
        u = (u0 + u1) / 2
        v = (v0 + v1) / 2
        surf_normal = surf.normal(u, v)
        if first_normal.cross(surf_normal).Length > err:
            return None

    normal = first_normal

    return normal


def find_plane(shape, tol=-1):
    """Find the plane containing the shape if possible.
    Use this function as a workaround due Part.Shape.findPlane
    fail to find plane on BSpline surfaces."""

    if shape.isNull():
        return None

    if shape.ShapeType == "Vertex":
        return None

    if is_straight_line(shape, tol):
        return None

    plane = shape.findPlane(tol)
    if plane:
        return plane
    elif len(shape.Faces) >= 1:
        # in case shape have BSpline surfaces
        normal = get_spline_surface_normal(shape, tol)
        if normal:
            position = shape.CenterOfMass
            return Part.Plane(position, normal)
        else:
            return None
    else:
        return None


def calculatePlacement(shape):
    """Return a placement located in the center of gravity of the shape.

    If the given shape is planar, return a placement located at the center
    of gravity of the shape, and oriented towards the shape's normal.
    Otherwise, it returns a null placement.
    """
    if not is_planar(shape):
        return App.Placement()

    pos = shape.BoundBox.Center
    norm = get_normal(shape)
    # for backward compatibility with previous getNormal implementation
    if norm is None:
        norm = App.Vector(0, 0, 1)
    pla = App.Placement()
    pla.Base = pos
    r = getRotation(norm)

    if r:
        pla.Rotation = r

    return pla


def mirror(point, edge):
    """Find mirror point relative to an edge."""
    normPoint = point.add(findDistance(point, edge, False))

    if normPoint:
        normPoint_point = App.Vector.sub(point, normPoint)
        normPoint_refl = normPoint_point.negative()
        refl = App.Vector.add(normPoint, normPoint_refl)
        return refl
    else:
        return None


def mirror_matrix(mtx, pos, nor):
    """Return a mirrored copy of a matrix.

    Parameters
    ----------
    mtx: Base::Matrix
        Matrix.
    pos: Base::Vector3
        Point on mirror plane.
    nor: Base::Vector3
        Normal of mirror plane.

    Returns
    -------
    Base::Matrix
    """
    # Code by Jolbas:
    # https://forum.freecad.org/viewtopic.php?p=702793#p702793
    mtx_copy = App.Matrix(mtx)
    mtx_copy.move(-pos)
    mtx_copy.scale(-1)
    mtx_copy = App.Rotation(nor, 180) * mtx_copy
    mtx_copy.move(pos)
    return mtx_copy


def uv_vectors_from_face(face, vec_z=App.Vector(0, 0, 1), tol=-1):
    """Return the u and v vectors of a planar face.

    It is up to the calling function to ensure the face is planar.

    If the u vector matches +/-vec_z, or the v vector matches -vec_z, the
    vectors are rotated to ensure the v vector matches +vec_z.

    Parameters
    ----------
    face: Part.Face
        Face.
    vec_z: Base::Vector3, optional
        Defaults to Vector(0, 0, 1).
        Z axis vector used for reference.
        Is replaced by Vector(0, 0, 1) if it matches the +/-normal of the face.
    tol: float, optional
        Defaults to -1.
        Internal tolerance. 1e-7 is used if tol <=0.

    Returns
    -------
    tuple
        U and v vector (Base::Vector3).
    """
    err = 1e-7 if tol <= 0 else tol
    if not vec_z.isEqual(App.Vector(0, 0, 1), err):
        nor = face.normalAt(0, 0)
        if vec_z.isEqual(nor, err) or vec_z.isEqual(nor.negative(), err):
            vec_z = App.Vector(0, 0, 1)
    vec_u, vec_v = face.tangentAt(0, 0)
    if face.Orientation == "Reversed":
        vec_u, vec_v = vec_v, vec_u
    if vec_v.isEqual(vec_z.negative(), err):
        vec_u, vec_v = vec_u.negative(), vec_v.negative()
    elif vec_u.isEqual(vec_z, err):
        vec_u, vec_v = vec_v.negative(), vec_u
    elif vec_u.isEqual(vec_z.negative(), err):
        vec_u, vec_v = vec_v, vec_u.negative()
    return vec_u, vec_v


def placement_from_face(face, vec_z=App.Vector(0, 0, 1), rotated=False, tol=-1):
    """Return a placement from the center of gravity, and the u and v vectors of a planar face.

    It is up to the calling function to ensure the face is planar.

    Parameters
    ----------
    face: Part.Face
        Face.
    vec_z: Base::Vector3, optional
        Defaults to Vector(0, 0, 1).
        Z axis vector used for reference.
        Is replaced by Vector(0, 0, 1) if it matches the +/-normal of the face.
    rotated: bool, optional
        Defaults to `False`.
        If `False` the v vector of the face defines the Y axis of the placement.
        If `True` the -v vector of the face defines the Z axis of the placement
        (used by Arch_Window).
        The u vector defines the X axis in both cases.
    tol: float, optional
        Defaults to -1.
        Internal tolerance. 1e-7 is used if tol <=0.

    Returns
    -------
    Base::Placement

    See also
    --------
    DraftGeomUtils.uv_vectors_from_face
    """
    pt_pos = face.CenterOfGravity
    vec_u, vec_v = uv_vectors_from_face(face, vec_z, tol)
    if rotated:
        return App.Placement(pt_pos, App.Rotation(vec_u, App.Vector(), vec_v.negative(), "XZY"))
    else:
        return App.Placement(pt_pos, App.Rotation(vec_u, vec_v, App.Vector(), "XYZ"))


def placement_from_points(pt_pos, pt_x, pt_y, as_vectors=False, tol=-1):
    """Return a placement from 3 points defining an origin, an X axis and a Y axis.

    If the vectors calculated from the arguments are too short or parallel,
    the returned placement will have a default rotation.

    Parameters
    ----------
    pt_pos: Base::Vector3
        Origin (Base of Placement).
    pt_x: Base::Vector3
        Point on positive X axis. Or X axis vector if as_vectors is `True`.
    pt_y: Base::Vector3
        Point on positive Y axis. Or Y axis vector if as_vectors is `True`.
    as_vectors: bool, optional
        Defaults to `False`.
        If `True` treat pt_x and pt_y as axis vectors.
    tol: float, optional
        Defaults to -1.
        Internal tolerance. 1e-7 is used if tol <=0.

    Returns
    -------
    Base::Placement

    See also
    --------
    DraftGeomUtils.getRotation
    DraftVecUtils.getRotation
    """
    err = 1e-7 if tol <= 0 else tol
    if as_vectors is False:
        vec_u = pt_x - pt_pos
        vec_v = pt_y - pt_pos
    else:
        vec_u = App.Vector(pt_x)
        vec_v = App.Vector(pt_y)

    if vec_u.Length < err or vec_v.Length < err:
        rot = App.Rotation()
    else:
        vec_u.normalize()
        vec_v.normalize()
        if vec_u.isEqual(vec_v, err) or vec_u.isEqual(vec_v.negative(), err):
            rot = App.Rotation()
        else:
            rot = App.Rotation(vec_u, vec_v, App.Vector(), "XYZ")

    return App.Placement(pt_pos, rot)


# Code separated from WorkingPlane.py (offsetToPoint function).
# Note that the return value of this function has the opposite sign.
def distance_to_plane(point, base, normal):
    """Return the signed distance from a plane to a point.

    The distance is positive if the point lies on the +normal side of the plane.

    Parameters
    ----------
    point: Base::Vector3
        Point to project.
    base: Base::Vector3
        Point on plane.
    normal: Base::Vector3
        Normal of plane.

    Returns
    -------
    float
    """
    return (point - base).dot(normal)


# Code separated from WorkingPlane.py (projectPoint function).
# See: https://github.com/FreeCAD/FreeCAD/pull/5307
def project_point_on_plane(point, base, normal, direction=None, force_projection=False, tol=-1):
    """Project a point onto a plane.

    Parameters
    ----------
    point: Base::Vector3
        Point to project.
    base: Base::Vector3
        Point on plane.
    normal: Base::Vector3
        Normal of plane.
    direction: Base::Vector3, optional
        Defaults to `None` in which case the normal is used.
        Direction of projection.
    force_projection: Bool, optional
        Defaults to `False`.
        If `True` forces the projection if the deviation between the direction
        and the normal is less than tol from the orthogonality. The direction
        of projection is then modified to a tol deviation between the direction
        and the orthogonal.
    tol: float, optional
        Defaults to -1.
        Internal tolerance. 1e-7 is used if tol <=0.

    Returns
    -------
    Base::Vector3 or `None`
    """
    err = 1e-7 if tol <= 0 else tol
    normal = App.Vector(normal).normalize()
    if direction is None:
        direction = normal
    else:
        direction = App.Vector(direction).normalize()

    cos = direction.dot(normal)
    delta_ax_proj = (point - base).dot(normal)
    # check the only conflicting case: direction orthogonal to normal
    if abs(cos) < err:
        if force_projection:
            cos = math.copysign(err, delta_ax_proj)
            direction = normal.cross(direction).cross(normal) - cos * normal
        else:
            return None

    return point - delta_ax_proj / cos * direction


# compatibility layer

getSplineNormal = get_spline_normal

getNormal = get_normal

isPlanar = is_planar


## @}