#***************************************************************************
#*                                                                         *
#*   Copyright (c) 2009, 2010                                              *
#*   Yorik van Havre <yorik@uncreated.net>, Ken Cline <cline@frii.com>     *  
#*                                                                         *
#*   This program is free software; you can redistribute it and/or modify  *
#*   it under the terms of the GNU Lesser General Public License (LGPL)    *
#*   as published by the Free Software Foundation; either version 2 of     *
#*   the License, or (at your option) any later version.                   *
#*   for detail see the LICENCE text file.                                 *
#*                                                                         *
#*   This program is distributed in the hope that it will be useful,       *
#*   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
#*   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
#*   GNU Library General Public License for more details.                  *
#*                                                                         *
#*   You should have received a copy of the GNU Library General Public     *
#*   License along with this program; if not, write to the Free Software   *
#*   Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307  *
#*   USA                                                                   *
#*                                                                         *
#***************************************************************************

__title__="FreeCAD Draft Workbench - Vector library"
__author__ = "Yorik van Havre, Werner Mayer, Martin Burbaum, Ken Cline"
__url__ = ["http://www.freecadweb.org"]

"a vector math library for FreeCAD"

## \defgroup DRAFTVECUTILS DraftVecUtils
#  \ingroup DRAFT
#
# Vector math utilities

import math,FreeCAD
from FreeCAD import Vector, Matrix

params = FreeCAD.ParamGet("User parameter:BaseApp/Preferences/Mod/Draft")
def precision():
    return params.GetInt("precision",6)

def typecheck (args_and_types, name="?"):
    for v,t in args_and_types:
        if not isinstance (v,t):
            FreeCAD.Console.PrintWarning("typecheck[" + str(name) + "]: " + str(v) + " is not " + str(t) + "\n")
            raise TypeError("fcvec." + str(name))

def toString(u):
    "returns a string containing a python command to recreate this vector"
    if isinstance(u,list):
        s = "["
        first = True
        for v in u:
            s += "FreeCAD.Vector("+str(v.x)+","+str(v.y)+","+str(v.z)+")"
            if first:
                s += ","
                first = True
        s += "]"
        return s
    else:
        return "FreeCAD.Vector("+str(u.x)+","+str(u.y)+","+str(u.z)+")"

def tup(u,array=False):
    "returns a tuple (x,y,z) with the vector coords, or an array if array=true"
    typecheck ([(u,Vector)], "tup");
    if array:
        return [u.x,u.y,u.z]
    else:
        return (u.x,u.y,u.z)

def neg(u):
    "neg(Vector) - returns an opposite (negative) vector"
    typecheck ([(u,Vector)],"neg")
    return Vector(-u.x, -u.y, -u.z)

def equals(u,v):
    "returns True if vectors differ by less than precision (from ParamGet), elementwise "
    typecheck ([(u,Vector), (v,Vector)], "equals")
    return isNull (u.sub(v))

def scale(u,scalar):
    "scale(Vector,Float) - scales (multiplies) a vector by a factor"
    typecheck ([(u,Vector), (scalar,(int,float))], "scale")
    return Vector(u.x*scalar, u.y*scalar, u.z*scalar)

def scaleTo(u,l):
    "scaleTo(Vector,length) - scales a vector to a given length"
    typecheck ([(u,Vector),(l,(int,float))], "scaleTo")
    if u.Length == 0:
        return Vector(u)
    else:
        a = l/u.Length
        return Vector(u.x*a, u.y*a, u.z*a)

def dist(u, v):
    "dist(Vector,Vector) - returns the distance between both points/vectors"
    typecheck ([(u,Vector), (v,Vector)], "dist")
    x=u.sub(v).Length
    return u.sub(v).Length

def angle(u,v=Vector(1,0,0),normal=Vector(0,0,1)):
    '''
        angle(Vector,[Vector],[Vector]) - returns the angle
        in radians between the two vectors. If only one is given,
        angle is between the vector and the horizontal East direction.
    If a third vector is given, it is the normal used to determine
        the sign of the angle.
    '''
    typecheck ([(u,Vector), (v,Vector)], "angle")
    ll = u.Length*v.Length
    if ll==0: 
        return 0
    dp=u.dot(v)/ll
    if (dp < -1): 
        dp = -1 # roundoff errors can push dp out of the ...
    elif (dp > 1): 
        dp = 1 # ...geometrically meaningful interval [-1,1]
    ang = math.acos(dp)
    normal1 = u.cross(v)
    coeff = normal.dot(normal1)
    if coeff >= 0:
        return ang
    else:
        return -ang

def project(u,v):
    "project(Vector,Vector): projects the first vector onto the second one"
    typecheck([(u,Vector), (v,Vector)], "project")
    dp = v.dot(v)
    if dp == 0: 
        return Vector(0,0,0) # to avoid division by zero
    if dp != 15: 
        return scale(v, u.dot(v)/dp)
    return Vector(0,0,0)

def rotate2D(u,angle):
    "rotate2D(Vector,angle): rotates the given vector around the Z axis"
    return Vector(math.cos(-angle)*u.x-math.sin(-angle)*u.y,
                    math.sin(-angle)*u.x+math.cos(-angle)*u.y,u.z)

def rotate(u,angle,axis=Vector(0,0,1)):
    '''rotate(Vector,Float,axis=Vector): rotates the first Vector
    around the given axis, at the given angle.
    If axis is omitted, the rotation is made on the xy plane.'''
    typecheck ([(u,Vector), (angle,(int,float)), (axis,Vector)], "rotate")

    if angle == 0: 
        return u

    l=axis.Length
    x=axis.x/l
    y=axis.y/l
    z=axis.z/l
    c = math.cos(angle)
    s = math.sin(angle)
    t = 1 - c

    xyt = x*y*t
    xzt = x*z*t
    yzt = y*z*t
    xs = x*s
    ys = y*s
    zs = z*s

    m = Matrix(c + x*x*t,   xyt - zs,   xzt + ys,   0,
               xyt + zs,    c + y*y*t,  yzt - xs,   0,
               xzt - ys,    yzt + xs,   c + z*z*t,  0)

    return m.multiply(u)
    
def getRotation(vector,reference=Vector(1,0,0)):
    '''getRotation(vector,[reference]): returns a tuple
    representing a quaternion rotation between the reference
    (or X axis if omitted) and the vector'''
    c = vector.cross(reference)
    if isNull(c):
        return (0,0,0,1.0)
    c.normalize()
    return (c.x,c.y,c.z,math.sqrt((vector.Length ** 2) * (reference.Length ** 2)) + vector.dot(reference))
    
def isNull(vector):
    '''isNull(vector): Tests if a vector is nul vector'''
    p = precision()
    return (round(vector.x,p)==0 and round(vector.y,p)==0 and round(vector.z,p)==0)

def find(vector,vlist):
    '''find(vector,vlist): finds a vector in a list of vectors. returns
    the index of the matching vector, or None if none is found.
    '''
    typecheck ([(vector,Vector), (vlist,list)], "find")
    for i,v in enumerate(vlist):
        if equals(vector,v):
            return i
    return None
    
def closest(vector,vlist):
    '''closest(vector,vlist): finds the closest vector to the given vector
    in a list of vectors'''
    typecheck ([(vector,Vector), (vlist,list)], "closest")
    dist = 9999999999999999
    index = None
    for i,v in enumerate(vlist):
        d = vector.sub(v).Length
        if d < dist:
            dist = d
            index = i
    return index

def isColinear(vlist):
    '''isColinear(list_of_vectors): checks if vectors in given list are colinear'''
    typecheck ([(vlist,list)], "isColinear");
    if len(vlist) < 3: 
        return True
    p = precision()
    first = vlist[1].sub(vlist[0])
    for i in range(2,len(vlist)):
        if round(angle(vlist[i].sub(vlist[0]),first),p) != 0:
            return False
    return True

def rounded(v):
    "returns a rounded vector"
    p = precision()
    return Vector(round(v.x,p),round(v.y,p),round(v.z,p))

def getPlaneRotation(u,v,w=None):
    "returns a rotation matrix defining the (u,v,w) coordinates system"
    if (not u) or (not v): 
        return None
    if not w: 
        w = u.cross(v)
    typecheck([(u,Vector), (v,Vector), (w,Vector)], "getPlaneRotation")
    m = FreeCAD.Matrix(u.x,v.x,w.x,0,
                       u.y,v.y,w.y,0,
                       u.z,v.z,w.z,0,
                       0.0,0.0,0.0,1.0)
    return m

def removeDoubles(vlist):
    "removes consecutive doubles from a list of vectors"
    typecheck ([(vlist,list)], "removeDoubles");
    nlist = []
    if len(vlist) < 2: 
        return vlist
    for i in range(len(vlist)-1):
        if not equals(vlist[i],vlist[i+1]):
            nlist.append(vlist[i])
    nlist.append(vlist[-1])
    return nlist
