#!/usr/bin/env python 
'''
Copyright (C) 2005,2007,2008 Aaron Spike, aaron@ekips.org
Copyright (C) 2008,2010 Alvin Penner, penner@vaxxine.com

This file output script for Inkscape creates a AutoCAD R14 DXF file.
The spec can be found here: http://www.autodesk.com/techpubs/autocad/acadr14/dxf/index.htm.

File history:
- template dxf_outlines.dxf added Feb 2008 by Alvin Penner
- ROBO-Master output option added Aug 2008
- ROBO-Master multispline output added Sept 2008
- LWPOLYLINE output modification added Dec 2008
- toggle between LINE/LWPOLYLINE added Jan 2010
- support for transform elements added July 2010
- support for layers added July 2010
- support for rectangle added Dec 2010

This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 2 of the License, or
(at your option) any later version.

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 General Public License for more details.

You should have received a copy of the GNU 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
'''
import inkex, simplestyle, simpletransform, cubicsuperpath, coloreffect, dxf_templates, math
import gettext
_ = gettext.gettext

try:
    from numpy import *
    from numpy.linalg import solve
except:
    inkex.errormsg(_("Failed to import the numpy or numpy.linalg modules. These modules are required by this extension. Please install them and try again."))
    inkex.sys.exit()

def pointdistance((x1,y1),(x2,y2)):
    return math.sqrt(((x2 - x1) ** 2) + ((y2 - y1) ** 2))

def get_fit(u, csp, col):
    return (1-u)**3*csp[0][col] + 3*(1-u)**2*u*csp[1][col] + 3*(1-u)*u**2*csp[2][col] + u**3*csp[3][col]

def get_matrix(u, i, j):
    if j == i + 2:
        return (u[i]-u[i-1])*(u[i]-u[i-1])/(u[i+2]-u[i-1])/(u[i+1]-u[i-1])
    elif j == i + 1:
        return ((u[i]-u[i-1])*(u[i+2]-u[i])/(u[i+2]-u[i-1]) + (u[i+1]-u[i])*(u[i]-u[i-2])/(u[i+1]-u[i-2]))/(u[i+1]-u[i-1])
    elif j == i:
        return (u[i+1]-u[i])*(u[i+1]-u[i])/(u[i+1]-u[i-2])/(u[i+1]-u[i-1])
    else:
        return 0

class MyEffect(inkex.Effect):
    def __init__(self):
        inkex.Effect.__init__(self)
        self.OptionParser.add_option("-R", "--ROBO", action="store", type="string", dest="ROBO")
        self.OptionParser.add_option("-P", "--POLY", action="store", type="string", dest="POLY")
        self.OptionParser.add_option("--units", action="store", type="string", dest="units")
        self.OptionParser.add_option("--encoding", action="store", type="string", dest="char_encode", default="latin_1")
        self.OptionParser.add_option("--tab", action="store", type="string", dest="tab")
        self.OptionParser.add_option("--inputhelp", action="store", type="string", dest="inputhelp")
        self.dxf = []
        self.handle = 255                       # handle for DXF ENTITY
        self.layers = ['0']
        self.layer = '0'                        # mandatory layer
        self.csp_old = [[0.0,0.0]]*4            # previous spline
        self.d = array([0], float)              # knot vector
        self.poly = [[0.0,0.0]]                 # LWPOLYLINE data
    def output(self):
        print ''.join(self.dxf)
    def dxf_add(self, str):
        self.dxf.append(str.encode(self.options.char_encode))
    def dxf_line(self,csp):
        self.handle += 1
        self.dxf_add("  0\nLINE\n  5\n%x\n100\nAcDbEntity\n  8\n%s\n 62\n%d\n100\nAcDbLine\n" % (self.handle, self.layer, self.color))
        self.dxf_add(" 10\n%f\n 20\n%f\n 30\n0.0\n 11\n%f\n 21\n%f\n 31\n0.0\n" % (csp[0][0],csp[0][1],csp[1][0],csp[1][1]))
    def LWPOLY_line(self,csp):
        if (abs(csp[0][0] - self.poly[-1][0]) > .0001
            or abs(csp[0][1] - self.poly[-1][1]) > .0001):
            self.LWPOLY_output()                            # terminate current polyline
            self.poly = [csp[0]]                            # initiallize new polyline
            self.color_LWPOLY = self.color
            self.layer_LWPOLY = self.layer
            self.closed_LWPOLY = self.closed
        self.poly.append(csp[1])
    def LWPOLY_output(self):
        if len(self.poly) == 1:
            return
        self.handle += 1
        self.dxf_add("  0\nLWPOLYLINE\n  5\n%x\n100\nAcDbEntity\n  8\n%s\n 62\n%d\n100\nAcDbPolyline\n 90\n%d\n 70\n%d\n" % (self.handle, self.layer_LWPOLY, self.color_LWPOLY, len(self.poly), self.closed_LWPOLY))
        for i in range(len(self.poly)):
            self.dxf_add(" 10\n%f\n 20\n%f\n 30\n0.0\n" % (self.poly[i][0],self.poly[i][1]))
    def dxf_spline(self,csp):
        knots = 8
        ctrls = 4
        self.handle += 1
        self.dxf_add("  0\nSPLINE\n  5\n%x\n100\nAcDbEntity\n  8\n%s\n 62\n%d\n100\nAcDbSpline\n" % (self.handle, self.layer, self.color))
        self.dxf_add(" 70\n8\n 71\n3\n 72\n%d\n 73\n%d\n 74\n0\n" % (knots, ctrls))
        for i in range(2):
            for j in range(4):
                self.dxf_add(" 40\n%d\n" % i)
        for i in csp:
            self.dxf_add(" 10\n%f\n 20\n%f\n 30\n0.0\n" % (i[0],i[1]))
    def ROBO_spline(self,csp):
        # this spline has zero curvature at the endpoints, as in ROBO-Master
        if (abs(csp[0][0] - self.csp_old[3][0]) > .0001
            or abs(csp[0][1] - self.csp_old[3][1]) > .0001
            or abs((csp[1][1]-csp[0][1])*(self.csp_old[3][0]-self.csp_old[2][0]) - (csp[1][0]-csp[0][0])*(self.csp_old[3][1]-self.csp_old[2][1])) > .001):
            self.ROBO_output()                              # terminate current spline
            self.xfit = array([csp[0][0]], float)           # initiallize new spline
            self.yfit = array([csp[0][1]], float)
            self.d = array([0], float)
            self.color_ROBO = self.color
            self.layer_ROBO = self.layer
        self.xfit = concatenate((self.xfit, zeros((3))))    # append to current spline
        self.yfit = concatenate((self.yfit, zeros((3))))
        self.d = concatenate((self.d, zeros((3))))
        for i in range(1, 4):
            j = len(self.d) + i - 4
            self.xfit[j] = get_fit(i/3.0, csp, 0)
            self.yfit[j] = get_fit(i/3.0, csp, 1)
            self.d[j] = self.d[j-1] + pointdistance((self.xfit[j-1],self.yfit[j-1]),(self.xfit[j],self.yfit[j]))
        self.csp_old = csp
    def ROBO_output(self):
        if len(self.d) == 1:
            return
        fits = len(self.d)
        ctrls = fits + 2
        knots = ctrls + 4
        self.xfit = concatenate((self.xfit, zeros((2))))    # pad with 2 endpoint constraints
        self.yfit = concatenate((self.yfit, zeros((2))))    # pad with 2 endpoint constraints
        self.d = concatenate((self.d, zeros((6))))          # pad with 3 duplicates at each end
        self.d[fits+2] = self.d[fits+1] = self.d[fits] = self.d[fits-1]
        solmatrix = zeros((ctrls,ctrls), dtype=float)
        for i in range(fits):
            solmatrix[i,i]   = get_matrix(self.d, i, i)
            solmatrix[i,i+1] = get_matrix(self.d, i, i+1)
            solmatrix[i,i+2] = get_matrix(self.d, i, i+2)
        solmatrix[fits, 0]   = self.d[2]/self.d[fits-1]     # curvature at start = 0
        solmatrix[fits, 1]   = -(self.d[1] + self.d[2])/self.d[fits-1]
        solmatrix[fits, 2]   = self.d[1]/self.d[fits-1]
        solmatrix[fits+1, fits-1] = (self.d[fits-1] - self.d[fits-2])/self.d[fits-1]   # curvature at end = 0
        solmatrix[fits+1, fits]   = (self.d[fits-3] + self.d[fits-2] - 2*self.d[fits-1])/self.d[fits-1]
        solmatrix[fits+1, fits+1] = (self.d[fits-1] - self.d[fits-3])/self.d[fits-1]
        xctrl = solve(solmatrix, self.xfit)
        yctrl = solve(solmatrix, self.yfit)
        self.handle += 1
        self.dxf_add("  0\nSPLINE\n  5\n%x\n100\nAcDbEntity\n  8\n%s\n 62\n%d\n100\nAcDbSpline\n" % (self.handle, self.layer_ROBO, self.color_ROBO))
        self.dxf_add(" 70\n0\n 71\n3\n 72\n%d\n 73\n%d\n 74\n%d\n" % (knots, ctrls, fits))
        for i in range(knots):
            self.dxf_add(" 40\n%f\n" % self.d[i-3])
        for i in range(ctrls):
            self.dxf_add(" 10\n%f\n 20\n%f\n 30\n0.0\n" % (xctrl[i],yctrl[i]))
        for i in range(fits):
            self.dxf_add(" 11\n%f\n 21\n%f\n 31\n0.0\n" % (self.xfit[i],self.yfit[i]))

    def process_shape(self, node, mat):
        rgb = (0,0,0)
        style = node.get('style')
        if style:
            style = simplestyle.parseStyle(style)
            if style.has_key('stroke'):
                if style['stroke'] and style['stroke'] != 'none' and style['stroke'][0:3] != 'url':
                    rgb = simplestyle.parseColor(style['stroke'])
        hsl = coloreffect.ColorEffect.rgb_to_hsl(coloreffect.ColorEffect(),rgb[0]/255.0,rgb[1]/255.0,rgb[2]/255.0)
        self.closed = 0                                 # only for LWPOLYLINE
        self.color = 7                                  # default is black
        if hsl[2]:
            self.color = 1 + (int(6*hsl[0] + 0.5) % 6)  # use 6 hues
        if node.tag == inkex.addNS('path','svg'):
            d = node.get('d')
            if not d:
                return
            if (d[-1] == 'z' or d[-1] == 'Z'):
                self.closed = 1
            p = cubicsuperpath.parsePath(d)
        elif node.tag == inkex.addNS('rect','svg'):
            self.closed = 1
            x = float(node.get('x'))
            y = float(node.get('y'))
            width = float(node.get('width'))
            height = float(node.get('height'))
            p = [[[x, y],[x, y],[x, y]]]
            p.append([[x + width, y],[x + width, y],[x + width, y]])
            p.append([[x + width, y + height],[x + width, y + height],[x + width, y + height]])
            p.append([[x, y + height],[x, y + height],[x, y + height]])
            p.append([[x, y],[x, y],[x, y]])
            p = [p]
        else:
            return
        trans = node.get('transform')
        if trans:
            mat = simpletransform.composeTransform(mat, simpletransform.parseTransform(trans))
        simpletransform.applyTransformToPath(mat, p)
        for sub in p:
            for i in range(len(sub)-1):
                s = sub[i]
                e = sub[i+1]
                if s[1] == s[2] and e[0] == e[1]:
                    if (self.options.POLY == 'true'):
                        self.LWPOLY_line([s[1],e[1]])
                    else:
                        self.dxf_line([s[1],e[1]])
                elif (self.options.ROBO == 'true'):
                    self.ROBO_spline([s[1],s[2],e[0],e[1]])
                else:
                    self.dxf_spline([s[1],s[2],e[0],e[1]])

    def process_clone(self, node):
        trans = node.get('transform')
        x = node.get('x')
        y = node.get('y')
        mat = [[1.0, 0.0, 0.0], [0.0, 1.0, 0.0]]
        if trans:
            mat = simpletransform.composeTransform(mat, simpletransform.parseTransform(trans))
        if x:
            mat = simpletransform.composeTransform(mat, [[1.0, 0.0, float(x)], [0.0, 1.0, 0.0]])
        if y:
            mat = simpletransform.composeTransform(mat, [[1.0, 0.0, 0.0], [0.0, 1.0, float(y)]])
        # push transform
        if trans or x or y:
            self.groupmat.append(simpletransform.composeTransform(self.groupmat[-1], mat))
        # get referenced node
        refid = node.get(inkex.addNS('href','xlink'))
        refnode = self.getElementById(refid[1:])
        if refnode is not None:
            if refnode.tag == inkex.addNS('g','svg'):
                self.process_group(refnode)
            elif refnode.tag == inkex.addNS('use', 'svg'):
                self.process_clone(refnode)
            else:
                self.process_shape(refnode, self.groupmat[-1])
        # pop transform
        if trans or x or y:
            self.groupmat.pop()

    def process_group(self, group):
        if group.get(inkex.addNS('groupmode', 'inkscape')) == 'layer':
            layer = group.get(inkex.addNS('label', 'inkscape'))
            layer = layer.replace(' ', '_')
            if layer in self.layers:
                self.layer = layer
        trans = group.get('transform')
        if trans:
            self.groupmat.append(simpletransform.composeTransform(self.groupmat[-1], simpletransform.parseTransform(trans)))
        for node in group:
            if node.tag == inkex.addNS('g','svg'):
                self.process_group(node)
            elif node.tag == inkex.addNS('use', 'svg'):
                self.process_clone(node)
            else:
                self.process_shape(node, self.groupmat[-1])
        if trans:
            self.groupmat.pop()

    def effect(self):
        #References:   Minimum Requirements for Creating a DXF File of a 3D Model By Paul Bourke
        #              NURB Curves: A Guide for the Uninitiated By Philip J. Schneider
        #              The NURBS Book By Les Piegl and Wayne Tiller (Springer, 1995)
        # self.dxf_add("999\nDXF created by Inkscape\n")  # Some programs do not take comments in DXF files (KLayout 0.21.12 for example)
        self.dxf_add(dxf_templates.r14_header)
        for node in self.document.getroot().xpath('//svg:g', namespaces=inkex.NSS):
            if node.get(inkex.addNS('groupmode', 'inkscape')) == 'layer':
                layer = node.get(inkex.addNS('label', 'inkscape'))
                layer = layer.replace(' ', '_')
                if layer and not layer in self.layers:
                    self.layers.append(layer)
        self.dxf_add("  2\nLAYER\n  5\n2\n100\nAcDbSymbolTable\n 70\n%s\n" % len(self.layers))
        for i in range(len(self.layers)):
            self.dxf_add("  0\nLAYER\n  5\n%x\n100\nAcDbSymbolTableRecord\n100\nAcDbLayerTableRecord\n  2\n%s\n 70\n0\n  6\nCONTINUOUS\n" % (i + 80, self.layers[i]))
        self.dxf_add(dxf_templates.r14_style)

        scale = eval(self.options.units)
        if not scale:
            scale = 25.4/90     # if no scale is specified, assume inch as baseunit
        h = inkex.unittouu(self.document.getroot().xpath('@height', namespaces=inkex.NSS)[0])
        self.groupmat = [[[scale, 0.0, 0.0], [0.0, -scale, h*scale]]]
        doc = self.document.getroot()
        self.process_group(doc)
        if self.options.ROBO == 'true':
            self.ROBO_output()
        if self.options.POLY == 'true':
            self.LWPOLY_output()
        self.dxf_add(dxf_templates.r14_footer)

if __name__ == '__main__':
    e = MyEffect()
    e.affect()


# vim: expandtab shiftwidth=4 tabstop=8 softtabstop=4 fileencoding=utf-8 textwidth=99
