# ##### BEGIN GPL LICENSE BLOCK #####
#
#  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., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
#
# ##### END GPL LICENSE BLOCK #####

# <pep8 compliant>

# Script copyright (C) Campbell Barton
# Contributors: Campbell Barton, Jiri Hnidek, Paolo Ciccone

"""
This script imports a Wavefront OBJ files to Blender.

Usage:
Run this script from "File->Import" menu and then load the desired OBJ file.
Note, This loads mesh objects and materials only, nurbs and curves are not supported.

http://wiki.blender.org/index.php/Scripts/Manual/Import/wavefront_obj
"""

import os
import time
import bpy
import mathutils
from bpy_extras.io_utils import unpack_list, unpack_face_list
from bpy_extras.image_utils import load_image


def line_value(line_split):
    '''
    Returns 1 string represneting the value for this line
    None will be returned if theres only 1 word
    '''
    length = len(line_split)
    if length == 1:
        return None

    elif length == 2:
        return line_split[1]

    elif length > 2:
        return b' '.join(line_split[1:])


def obj_image_load(imagepath, DIR, recursive):
    '''
    Mainly uses comprehensiveImageLoad
    but tries to replace '_' with ' ' for Max's exporter replaces spaces with underscores.
    '''
    if b'_' in imagepath:
        image = load_image(imagepath.replace(b'_', b' '), DIR, recursive=recursive)
        if image:
            return image

    return load_image(imagepath, DIR, recursive=recursive, place_holder=True)


def create_materials(filepath, material_libs, unique_materials, unique_material_images, use_image_search):
    '''
    Create all the used materials in this obj,
    assign colors and images to the materials from all referenced material libs
    '''
    DIR = os.path.dirname(filepath)

    #==================================================================================#
    # This function sets textures defined in .mtl file                                 #
    #==================================================================================#
    def load_material_image(blender_material, context_material_name, imagepath, type):

        texture = bpy.data.textures.new(name=type, type='IMAGE')

        # Absolute path - c:\.. etc would work here
        image = obj_image_load(imagepath, DIR, use_image_search)
        has_data = False

        if image:
            texture.image = image
            has_data = image.has_data

        # Adds textures for materials (rendering)
        if type == 'Kd':
            if has_data and image.depth == 32:
                # Image has alpha

                mtex = blender_material.texture_slots.add()
                mtex.texture = texture
                mtex.texture_coords = 'UV'
                mtex.use_map_color_diffuse = True
                mtex.use_map_alpha = True

                texture.use_mipmap = True
                texture.use_interpolation = True
                texture.use_alpha = True
                blender_material.use_transparency = True
                blender_material.alpha = 0.0

                blender_material.game_settings.alpha_blend = 'ALPHA'
            else:
                mtex = blender_material.texture_slots.add()
                mtex.texture = texture
                mtex.texture_coords = 'UV'
                mtex.use_map_color_diffuse = True

            # adds textures to faces (Textured/Alt-Z mode)
            # Only apply the diffuse texture to the face if the image has not been set with the inline usemat func.
            unique_material_images[context_material_name] = image, has_data  # set the texface image

        elif type == 'Ka':
            mtex = blender_material.texture_slots.add()
            mtex.use_map_color_diffuse = False

            mtex.texture = texture
            mtex.texture_coords = 'UV'
            mtex.use_map_ambient = True

        elif type == 'Ks':
            mtex = blender_material.texture_slots.add()
            mtex.use_map_color_diffuse = False

            mtex.texture = texture
            mtex.texture_coords = 'UV'
            mtex.use_map_specular = True

        elif type == 'Bump':
            mtex = blender_material.texture_slots.add()
            mtex.use_map_color_diffuse = False

            mtex.texture = texture
            mtex.texture_coords = 'UV'
            mtex.use_map_normal = True

        elif type == 'D':
            mtex = blender_material.texture_slots.add()
            mtex.use_map_color_diffuse = False

            mtex.texture = texture
            mtex.texture_coords = 'UV'
            mtex.use_map_alpha = True
            blender_material.use_transparency = True
            blender_material.transparency_method = 'Z_TRANSPARENCY'
            blender_material.alpha = 0.0
            # Todo, unset deffuse material alpha if it has an alpha channel

        elif type == 'refl':
            mtex = blender_material.texture_slots.add()
            mtex.use_map_color_diffuse = False

            mtex.texture = texture
            mtex.texture_coords = 'UV'
            mtex.use_map_reflect = True

        else:
            raise Exception("invalid type %r" % type)

    # Add an MTL with the same name as the obj if no MTLs are spesified.
    temp_mtl = os.path.splitext((os.path.basename(filepath)))[0] + b'.mtl'

    if os.path.exists(os.path.join(DIR, temp_mtl)) and temp_mtl not in material_libs:
        material_libs.append(temp_mtl)
    del temp_mtl

    #Create new materials
    for name in unique_materials:  # .keys()
        if name is not None:
            unique_materials[name] = bpy.data.materials.new(name.decode('utf-8', "replace"))
            unique_material_images[name] = None, False  # assign None to all material images to start with, add to later.

    unique_materials[None] = None
    unique_material_images[None] = None, False

    for libname in material_libs:
        # print(libname)
        mtlpath = os.path.join(DIR, libname)
        if not os.path.exists(mtlpath):
            print ("\tMaterial not found MTL: %r" % mtlpath)
        else:
            #print('\t\tloading mtl: %e' % mtlpath)
            context_material = None
            mtl = open(mtlpath, 'rb')
            for line in mtl:  # .readlines():
                line = line.strip()
                if not line or line.startswith(b'#'):
                    pass
                elif line.startswith(b'newmtl'):
                    context_material_name = line_value(line.split())
                    context_material = unique_materials.get(context_material_name)

                elif context_material:
                    # we need to make a material to assign properties to it.
                    line_split = line.split()
                    line_lower = line.lower().lstrip()
                    if line_lower.startswith(b'ka'):
                        context_material.mirror_color = float(line_split[1]), float(line_split[2]), float(line_split[3])
                    elif line_lower.startswith(b'kd'):
                        context_material.diffuse_color = float(line_split[1]), float(line_split[2]), float(line_split[3])
                    elif line_lower.startswith(b'ks'):
                        context_material.specular_color = float(line_split[1]), float(line_split[2]), float(line_split[3])
                    elif line_lower.startswith(b'ns'):
                        context_material.specular_hardness = int((float(line_split[1]) * 0.51))
                    elif line_lower.startswith(b'ni'):  # Refraction index
                        context_material.raytrace_transparency.ior = max(1, min(float(line_split[1]), 3))  # between 1 and 3
                    elif line_lower.startswith(b'd') or line_lower.startswith(b'tr'):
                        context_material.alpha = float(line_split[1])
                        context_material.use_transparency = True
                        context_material.transparency_method = 'Z_TRANSPARENCY'
                    elif line_lower.startswith(b'tf'):
                        # rgb, filter color, blender has no support for this.
                        pass
                    elif line_lower.startswith(b'illum'):
                        illum = int(line_split[1])

                        do_ambient = True
                        do_highlight = False
                        do_reflection = False
                        do_transparency = False
                        do_glass = False
                        do_fresnel = False
                        do_raytrace = False

                        # inline comments are from the spec, v4.2
                        if illum == 0:
                            # Color on and Ambient off
                            do_ambient = False
                        elif illum == 1:
                            # Color on and Ambient on
                            pass
                        elif illum == 2:
                            # Highlight on
                            do_highlight = True
                        elif illum == 3:
                            # Reflection on and Ray trace on
                            do_reflection = True
                            do_raytrace = True
                        elif illum == 4:
                            # Transparency: Glass on
                            # Reflection: Ray trace on
                            do_transparency = True
                            do_reflection = True
                            do_glass = True
                            do_raytrace = True
                        elif illum == 5:
                            # Reflection: Fresnel on and Ray trace on
                            do_reflection = True
                            do_fresnel = True
                            do_raytrace = True
                        elif illum == 6:
                            # Transparency: Refraction on
                            # Reflection: Fresnel off and Ray trace on
                            do_transparency = True
                            do_reflection = True
                            do_raytrace = True
                        elif illum == 7:
                            # Transparency: Refraction on
                            # Reflection: Fresnel on and Ray trace on
                            do_transparency = True
                            do_reflection = True
                            do_fresnel = True
                            do_raytrace = True
                        elif illum == 8:
                            # Reflection on and Ray trace off
                            do_reflection = True
                        elif illum == 9:
                            # Transparency: Glass on
                            # Reflection: Ray trace off
                            do_transparency = True
                            do_reflection = True
                            do_glass = True
                        elif illum == 10:
                            # Casts shadows onto invisible surfaces

                            # blender cant do this
                            pass

                        if do_ambient:
                            context_material.ambient = 1.0
                        else:
                            context_material.ambient = 0.0

                        if do_highlight:
                            # FIXME, how else to use this?
                            context_material.specular_intensity = 1.0

                        if do_reflection:
                            context_material.raytrace_mirror.use = True
                            context_material.raytrace_mirror.reflect_factor = 1.0

                        if do_transparency:
                            context_material.use_transparency = True
                            context_material.transparency_method = 'RAYTRACE' if do_raytrace else 'Z_TRANSPARENCY'
                            context_material.alpha = 0.0

                        if do_glass:
                            context_material.raytrace_transparency.ior = 1.5

                        if do_fresnel:
                            context_material.raytrace_mirror.fresnel = 1.0  # could be any value for 'ON'

                        """
                        if do_raytrace:
                            context_material.use_raytrace = True
                        else:
                            context_material.use_raytrace = False
                        """
                        # XXX, this is not following the OBJ spec, but this was
                        # written when raytracing wasnt default, annoying to disable for blender users.
                        context_material.use_raytrace = True

                    elif line_lower.startswith(b'map_ka'):
                        img_filepath = line_value(line.split())
                        if img_filepath:
                            load_material_image(context_material, context_material_name, img_filepath, 'Ka')
                    elif line_lower.startswith(b'map_ks'):
                        img_filepath = line_value(line.split())
                        if img_filepath:
                            load_material_image(context_material, context_material_name, img_filepath, 'Ks')
                    elif line_lower.startswith(b'map_kd'):
                        img_filepath = line_value(line.split())
                        if img_filepath:
                            load_material_image(context_material, context_material_name, img_filepath, 'Kd')
                    elif line_lower.startswith(b'map_bump') or line_lower.startswith(b'bump'):  # 'bump' is incorrect but some files use it.
                        img_filepath = line_value(line.split())
                        if img_filepath:
                            load_material_image(context_material, context_material_name, img_filepath, 'Bump')
                    elif line_lower.startswith(b'map_d') or line_lower.startswith(b'map_tr'):  # Alpha map - Dissolve
                        img_filepath = line_value(line.split())
                        if img_filepath:
                            load_material_image(context_material, context_material_name, img_filepath, 'D')

                    elif line_lower.startswith(b'refl'):  # reflectionmap
                        img_filepath = line_value(line.split())
                        if img_filepath:
                            load_material_image(context_material, context_material_name, img_filepath, 'refl')
                    else:
                        print("\t%r:%r (ignored)" % (filepath, line))
            mtl.close()


def split_mesh(verts_loc, faces, unique_materials, filepath, SPLIT_OB_OR_GROUP):
    '''
    Takes vert_loc and faces, and separates into multiple sets of
    (verts_loc, faces, unique_materials, dataname)
    '''

    filename = os.path.splitext((os.path.basename(filepath)))[0]

    if not SPLIT_OB_OR_GROUP:
        # use the filename for the object name since we arnt chopping up the mesh.
        return [(verts_loc, faces, unique_materials, filename)]

    def key_to_name(key):
        # if the key is a tuple, join it to make a string
        if not key:
            return filename  # assume its a string. make sure this is true if the splitting code is changed
        else:
            return key

    # Return a key that makes the faces unique.
    face_split_dict = {}

    oldkey = -1  # initialize to a value that will never match the key

    for face in faces:
        key = face[4]

        if oldkey != key:
            # Check the key has changed.
            try:
                verts_split, faces_split, unique_materials_split, vert_remap = face_split_dict[key]
            except KeyError:
                faces_split = []
                verts_split = []
                unique_materials_split = {}
                vert_remap = [-1] * len(verts_loc)

                face_split_dict[key] = (verts_split, faces_split, unique_materials_split, vert_remap)

            oldkey = key

        face_vert_loc_indices = face[0]

        # Remap verts to new vert list and add where needed
        for enum, i in enumerate(face_vert_loc_indices):
            if vert_remap[i] == -1:
                new_index = len(verts_split)
                vert_remap[i] = new_index  # set the new remapped index so we only add once and can reference next time.
                face_vert_loc_indices[enum] = new_index  # remap to the local index
                verts_split.append(verts_loc[i])  # add the vert to the local verts
            else:
                face_vert_loc_indices[enum] = vert_remap[i]  # remap to the local index

            matname = face[2]
            if matname and matname not in unique_materials_split:
                unique_materials_split[matname] = unique_materials[matname]

        faces_split.append(face)

    # remove one of the itemas and reorder
    return [(value[0], value[1], value[2], key_to_name(key)) for key, value in list(face_split_dict.items())]


def create_mesh(new_objects,
                has_ngons,
                use_ngons,
                use_edges,
                verts_loc,
                verts_tex,
                faces,
                unique_materials,
                unique_material_images,
                unique_smooth_groups,
                vertex_groups,
                dataname,
                ):
    '''
    Takes all the data gathered and generates a mesh, adding the new object to new_objects
    deals with fgons, sharp edges and assigning materials
    '''
    from bpy_extras.mesh_utils import ngon_tesselate

    if not has_ngons:
        use_ngons = False

    if unique_smooth_groups:
        sharp_edges = {}
        smooth_group_users = {context_smooth_group: {} for context_smooth_group in list(unique_smooth_groups.keys())}
        context_smooth_group_old = -1

    # Split fgons into tri's
    fgon_edges = {}  # Used for storing fgon keys
    if use_edges:
        edges = []

    context_object = None

    # reverse loop through face indices
    for f_idx in range(len(faces) - 1, -1, -1):

        (face_vert_loc_indices,
         face_vert_tex_indices,
         context_material,
         context_smooth_group,
         context_object,
         ) = faces[f_idx]

        len_face_vert_loc_indices = len(face_vert_loc_indices)

        if len_face_vert_loc_indices == 1:
            faces.pop(f_idx)  # cant add single vert faces

        elif not face_vert_tex_indices or len_face_vert_loc_indices == 2:  # faces that have no texture coords are lines
            if use_edges:
                # generators are better in python 2.4+ but can't be used in 2.3
                # edges.extend( (face_vert_loc_indices[i], face_vert_loc_indices[i+1]) for i in xrange(len_face_vert_loc_indices-1) )
                edges.extend([(face_vert_loc_indices[i], face_vert_loc_indices[i + 1]) for i in range(len_face_vert_loc_indices - 1)])

            faces.pop(f_idx)
        else:

            # Smooth Group
            if unique_smooth_groups and context_smooth_group:
                # Is a part of of a smooth group and is a face
                if context_smooth_group_old is not context_smooth_group:
                    edge_dict = smooth_group_users[context_smooth_group]
                    context_smooth_group_old = context_smooth_group

                for i in range(len_face_vert_loc_indices):
                    i1 = face_vert_loc_indices[i]
                    i2 = face_vert_loc_indices[i - 1]
                    if i1 > i2:
                        i1, i2 = i2, i1

                    try:
                        edge_dict[i1, i2] += 1
                    except KeyError:
                        edge_dict[i1, i2] = 1

            # FGons into triangles
            if has_ngons and len_face_vert_loc_indices > 4:

                ngon_face_indices = ngon_tesselate(verts_loc, face_vert_loc_indices)
                faces.extend([([face_vert_loc_indices[ngon[0]],
                                face_vert_loc_indices[ngon[1]],
                                face_vert_loc_indices[ngon[2]],
                                ],
                               [face_vert_tex_indices[ngon[0]],
                                face_vert_tex_indices[ngon[1]],
                                face_vert_tex_indices[ngon[2]],
                                ],
                               context_material,
                               context_smooth_group,
                               context_object,
                              )
                             for ngon in ngon_face_indices]
                            )

                # edges to make fgons
                if use_ngons:
                    edge_users = {}
                    for ngon in ngon_face_indices:
                        for i in (0, 1, 2):
                            i1 = face_vert_loc_indices[ngon[i]]
                            i2 = face_vert_loc_indices[ngon[i - 1]]
                            if i1 > i2:
                                i1, i2 = i2, i1

                            try:
                                edge_users[i1, i2] += 1
                            except KeyError:
                                edge_users[i1, i2] = 1

                    for key, users in edge_users.items():
                        if users > 1:
                            fgon_edges[key] = None

                # remove all after 3, means we dont have to pop this one.
                faces.pop(f_idx)

    # Build sharp edges
    if unique_smooth_groups:
        for edge_dict in list(smooth_group_users.values()):
            for key, users in list(edge_dict.items()):
                if users == 1:  # This edge is on the boundry of a group
                    sharp_edges[key] = None

    # map the material names to an index
    material_mapping = {name: i for i, name in enumerate(unique_materials)}  # enumerate over unique_materials keys()

    materials = [None] * len(unique_materials)

    for name, index in list(material_mapping.items()):
        materials[index] = unique_materials[name]

    me = bpy.data.meshes.new(dataname.decode('utf-8', "replace"))

    # make sure the list isnt too big
    for material in materials:
        me.materials.append(material)

    me.vertices.add(len(verts_loc))
    me.faces.add(len(faces))

    # verts_loc is a list of (x, y, z) tuples
    me.vertices.foreach_set("co", unpack_list(verts_loc))

    # faces is a list of (vert_indices, texco_indices, ...) tuples
    # XXX faces should contain either 3 or 4 verts
    # XXX no check for valid face indices
    me.faces.foreach_set("vertices_raw", unpack_face_list([f[0] for f in faces]))

    if verts_tex and me.faces:
        me.uv_textures.new()

    context_material_old = -1  # avoid a dict lookup
    mat = 0  # rare case it may be un-initialized.
    me_faces = me.faces

    for i, face in enumerate(faces):
        if len(face[0]) < 2:
            pass  # raise "bad face"
        elif len(face[0]) == 2:
            if use_edges:
                edges.append(face[0])
        else:

            blender_face = me.faces[i]

            (face_vert_loc_indices,
             face_vert_tex_indices,
             context_material,
             context_smooth_group,
             context_object,
             ) = face

            if context_smooth_group:
                blender_face.use_smooth = True

            if context_material:
                if context_material_old is not context_material:
                    mat = material_mapping[context_material]
                    context_material_old = context_material

                blender_face.material_index = mat
#                blender_face.mat= mat

            if verts_tex:

                blender_tface = me.uv_textures[0].data[i]

                if context_material:
                    image, has_data = unique_material_images[context_material]
                    if image:  # Can be none if the material dosnt have an image.
                        blender_tface.image = image

                # BUG - Evil eekadoodle problem where faces that have vert index 0 location at 3 or 4 are shuffled.
                if len(face_vert_loc_indices) == 4:
                    if face_vert_loc_indices[2] == 0 or face_vert_loc_indices[3] == 0:
                        face_vert_tex_indices = face_vert_tex_indices[2], face_vert_tex_indices[3], face_vert_tex_indices[0], face_vert_tex_indices[1]
                else:  # length of 3
                    if face_vert_loc_indices[2] == 0:
                        face_vert_tex_indices = face_vert_tex_indices[1], face_vert_tex_indices[2], face_vert_tex_indices[0]
                # END EEEKADOODLE FIX

                # assign material, uv's and image
                blender_tface.uv1 = verts_tex[face_vert_tex_indices[0]]
                blender_tface.uv2 = verts_tex[face_vert_tex_indices[1]]
                blender_tface.uv3 = verts_tex[face_vert_tex_indices[2]]

                if len(face_vert_loc_indices) == 4:
                    blender_tface.uv4 = verts_tex[face_vert_tex_indices[3]]

#                for ii, uv in enumerate(blender_face.uv):
#                    uv.x, uv.y=  verts_tex[face_vert_tex_indices[ii]]
    del me_faces
#     del ALPHA

    if use_edges and not edges:
        use_edges = False

    if use_edges:
        me.edges.add(len(edges))

        # edges should be a list of (a, b) tuples
        me.edges.foreach_set("vertices", unpack_list(edges))
#         me_edges.extend( edges )

#     del me_edges

    # Add edge faces.
#     me_edges= me.edges

    def edges_match(e1, e2):
        return (e1[0] == e2[0] and e1[1] == e2[1]) or (e1[0] == e2[1] and e1[1] == e2[0])

    # XXX slow
#     if use_ngons and fgon_edges:
#         for fgon_edge in fgon_edges.keys():
#             for ed in me.edges:
#                 if edges_match(fgon_edge, ed.vertices):
#                     ed.is_fgon = True

#     if use_ngons and fgon_edges:
#         FGON= Mesh.EdgeFlags.FGON
#         for ed in me.findEdges( fgon_edges.keys() ):
#             if ed is not None:
#                 me_edges[ed].flag |= FGON
#         del FGON

    # XXX slow
#     if unique_smooth_groups and sharp_edges:
#         for sharp_edge in sharp_edges.keys():
#             for ed in me.edges:
#                 if edges_match(sharp_edge, ed.vertices):
#                     ed.use_edge_sharp = True

#     if unique_smooth_groups and sharp_edges:
#         SHARP= Mesh.EdgeFlags.SHARP
#         for ed in me.findEdges( sharp_edges.keys() ):
#             if ed is not None:
#                 me_edges[ed].flag |= SHARP
#         del SHARP

    me.validate()
    me.update(calc_edges=use_edges)

    ob = bpy.data.objects.new("Mesh", me)
    new_objects.append(ob)

    # Create the vertex groups. No need to have the flag passed here since we test for the
    # content of the vertex_groups. If the user selects to NOT have vertex groups saved then
    # the following test will never run
    for group_name, group_indices in vertex_groups.items():
        group = ob.vertex_groups.new(group_name.decode('utf-8', "replace"))
        group.add(group_indices, 1.0, 'REPLACE')


def create_nurbs(context_nurbs, vert_loc, new_objects):
    '''
    Add nurbs object to blender, only support one type at the moment
    '''
    deg = context_nurbs.get(b'deg', (3,))
    curv_range = context_nurbs.get(b'curv_range')
    curv_idx = context_nurbs.get(b'curv_idx', [])
    parm_u = context_nurbs.get(b'parm_u', [])
    parm_v = context_nurbs.get(b'parm_v', [])
    name = context_nurbs.get(b'name', b'ObjNurb')
    cstype = context_nurbs.get(b'cstype')

    if cstype is None:
        print('\tWarning, cstype not found')
        return
    if cstype != b'bspline':
        print('\tWarning, cstype is not supported (only bspline)')
        return
    if not curv_idx:
        print('\tWarning, curv argument empty or not set')
        return
    if len(deg) > 1 or parm_v:
        print('\tWarning, surfaces not supported')
        return

    cu = bpy.data.curves.new(name.decode('utf-8', "replace"), 'CURVE')
    cu.dimensions = '3D'

    nu = cu.splines.new('NURBS')
    nu.points.add(len(curv_idx) - 1)  # a point is added to start with
    nu.points.foreach_set("co", [co_axis for vt_idx in curv_idx for co_axis in (vert_loc[vt_idx] + (1.0,))])

    nu.order_u = deg[0] + 1

    # get for endpoint flag from the weighting
    if curv_range and len(parm_u) > deg[0] + 1:
        do_endpoints = True
        for i in range(deg[0] + 1):

            if abs(parm_u[i] - curv_range[0]) > 0.0001:
                do_endpoints = False
                break

            if abs(parm_u[-(i + 1)] - curv_range[1]) > 0.0001:
                do_endpoints = False
                break

    else:
        do_endpoints = False

    if do_endpoints:
        nu.use_endpoint_u = True

    # close
    '''
    do_closed = False
    if len(parm_u) > deg[0]+1:
        for i in xrange(deg[0]+1):
            #print curv_idx[i], curv_idx[-(i+1)]

            if curv_idx[i]==curv_idx[-(i+1)]:
                do_closed = True
                break

    if do_closed:
        nu.use_cyclic_u = True
    '''

    ob = bpy.data.objects.new(name.decode('utf-8', "replace"), cu)

    new_objects.append(ob)


def strip_slash(line_split):
    if line_split[-1][-1] == 92:  # '\' char
        if len(line_split[-1]) == 1:
            line_split.pop()  # remove the \ item
        else:
            line_split[-1] = line_split[-1][:-1]  # remove the \ from the end last number
        return True
    return False


def get_float_func(filepath):
    '''
    find the float function for this obj file
    - whether to replace commas or not
    '''
    file = open(filepath, 'rb')
    for line in file:  # .readlines():
        line = line.lstrip()
        if line.startswith(b'v'):  # vn vt v
            if b',' in line:
                file.close()
                return lambda f: float(f.replace(b',', b'.'))
            elif b'.' in line:
                file.close()
                return float

    file.close()
    # in case all vert values were ints
    return float


def load(operator, context, filepath,
         global_clamp_size=0.0,
         use_ngons=True,
         use_smooth_groups=True,
         use_edges=True,
         use_split_objects=True,
         use_split_groups=True,
         use_image_search=True,
         use_groups_as_vgroups=False,
         global_matrix=None,
         ):
    '''
    Called by the user interface or another script.
    load_obj(path) - should give acceptable results.
    This function passes the file and sends the data off
        to be split into objects and then converted into mesh objects
    '''
    print('\nimporting obj %r' % filepath)

    filepath = os.fsencode(filepath)

    if global_matrix is None:
        global_matrix = mathutils.Matrix()

    if use_split_objects or use_split_groups:
        use_groups_as_vgroups = False

    time_main = time.time()

    verts_loc = []
    verts_tex = []
    faces = []  # tuples of the faces
    material_libs = []  # filanems to material libs this uses
    vertex_groups = {}  # when use_groups_as_vgroups is true

    # Get the string to float conversion func for this file- is 'float' for almost all files.
    float_func = get_float_func(filepath)

    # Context variables
    context_material = None
    context_smooth_group = None
    context_object = None
    context_vgroup = None

    # Nurbs
    context_nurbs = {}
    nurbs = []
    context_parm = b''  # used by nurbs too but could be used elsewhere

    has_ngons = False
    # has_smoothgroups= False - is explicit with len(unique_smooth_groups) being > 0

    # Until we can use sets
    unique_materials = {}
    unique_material_images = {}
    unique_smooth_groups = {}
    # unique_obects= {} - no use for this variable since the objects are stored in the face.

    # when there are faces that end with \
    # it means they are multiline-
    # since we use xreadline we cant skip to the next line
    # so we need to know whether
    context_multi_line = b''

    print("\tparsing obj file...")
    time_sub = time.time()
#     time_sub= sys.time()

    file = open(filepath, 'rb')
    for line in file:  # .readlines():
        line_split = line.split()

        if not line_split:
            continue

        line_start = line_split[0]  # we compare with this a _lot_

        if line_start == b'v':
            verts_loc.append((float_func(line_split[1]), float_func(line_split[2]), float_func(line_split[3])))

        elif line_start == b'vn':
            pass

        elif line_start == b'vt':
            verts_tex.append((float_func(line_split[1]), float_func(line_split[2])))

        # Handel faces lines (as faces) and the second+ lines of fa multiline face here
        # use 'f' not 'f ' because some objs (very rare have 'fo ' for faces)
        elif line_start == b'f' or context_multi_line == b'f':

            if context_multi_line:
                # use face_vert_loc_indices and face_vert_tex_indices previously defined and used the obj_face
                pass

            else:
                line_split = line_split[1:]
                face_vert_loc_indices = []
                face_vert_tex_indices = []

                # Instance a face
                faces.append((face_vert_loc_indices,
                              face_vert_tex_indices,
                              context_material,
                              context_smooth_group,
                              context_object,
                              ))

            if strip_slash(line_split):
                context_multi_line = b'f'
            else:
                context_multi_line = b''

            for v in line_split:
                obj_vert = v.split(b'/')
                vert_loc_index = int(obj_vert[0]) - 1
                # Add the vertex to the current group
                # *warning*, this wont work for files that have groups defined around verts
                if use_groups_as_vgroups and context_vgroup:
                    vertex_groups[context_vgroup].append(vert_loc_index)

                # Make relative negative vert indices absolute
                if vert_loc_index < 0:
                    vert_loc_index = len(verts_loc) + vert_loc_index + 1

                face_vert_loc_indices.append(vert_loc_index)

                if len(obj_vert) > 1 and obj_vert[1]:
                    # formatting for faces with normals and textures us
                    # loc_index/tex_index/nor_index

                    vert_tex_index = int(obj_vert[1]) - 1
                    # Make relative negative vert indices absolute
                    if vert_tex_index < 0:
                        vert_tex_index = len(verts_tex) + vert_tex_index + 1

                    face_vert_tex_indices.append(vert_tex_index)
                else:
                    # dummy
                    face_vert_tex_indices.append(0)

            if len(face_vert_loc_indices) > 4:
                has_ngons = True

        elif use_edges and (line_start == b'l' or context_multi_line == b'l'):
            # very similar to the face load function above with some parts removed

            if context_multi_line:
                # use face_vert_loc_indices and face_vert_tex_indices previously defined and used the obj_face
                pass

            else:
                line_split = line_split[1:]
                face_vert_loc_indices = []
                face_vert_tex_indices = []

                # Instance a face
                faces.append((face_vert_loc_indices,
                              face_vert_tex_indices,
                              context_material,
                              context_smooth_group,
                              context_object,
                              ))

            if strip_slash(line_split):
                context_multi_line = b'l'
            else:
                context_multi_line = b''

            # isline = line_start == b'l'  # UNUSED

            for v in line_split:
                vert_loc_index = int(v) - 1

                # Make relative negative vert indices absolute
                if vert_loc_index < 0:
                    vert_loc_index = len(verts_loc) + vert_loc_index + 1

                face_vert_loc_indices.append(vert_loc_index)

        elif line_start == b's':
            if use_smooth_groups:
                context_smooth_group = line_value(line_split)
                if context_smooth_group == b'off':
                    context_smooth_group = None
                elif context_smooth_group:  # is not None
                    unique_smooth_groups[context_smooth_group] = None

        elif line_start == b'o':
            if use_split_objects:
                context_object = line_value(line_split)
                # unique_obects[context_object]= None

        elif line_start == b'g':
            if use_split_groups:
                context_object = line_value(line.split())
                # print 'context_object', context_object
                # unique_obects[context_object]= None
            elif use_groups_as_vgroups:
                context_vgroup = line_value(line.split())
                if context_vgroup and context_vgroup != b'(null)':
                    vertex_groups.setdefault(context_vgroup, [])
                else:
                    context_vgroup = None  # dont assign a vgroup

        elif line_start == b'usemtl':
            context_material = line_value(line.split())
            unique_materials[context_material] = None
        elif line_start == b'mtllib':  # usemap or usemat
            material_libs = list(set(material_libs) | set(line.split()[1:]))  # can have multiple mtllib filenames per line, mtllib can appear more than once, so make sure only occurance of material exists

            # Nurbs support
        elif line_start == b'cstype':
            context_nurbs[b'cstype'] = line_value(line.split())  # 'rat bspline' / 'bspline'
        elif line_start == b'curv' or context_multi_line == b'curv':
            curv_idx = context_nurbs[b'curv_idx'] = context_nurbs.get(b'curv_idx', [])  # in case were multiline

            if not context_multi_line:
                context_nurbs[b'curv_range'] = float_func(line_split[1]), float_func(line_split[2])
                line_split[0:3] = []  # remove first 3 items

            if strip_slash(line_split):
                context_multi_line = b'curv'
            else:
                context_multi_line = b''

            for i in line_split:
                vert_loc_index = int(i) - 1

                if vert_loc_index < 0:
                    vert_loc_index = len(verts_loc) + vert_loc_index + 1

                curv_idx.append(vert_loc_index)

        elif line_start == b'parm' or context_multi_line == b'parm':
            if context_multi_line:
                context_multi_line = b''
            else:
                context_parm = line_split[1]
                line_split[0:2] = []  # remove first 2

            if strip_slash(line_split):
                context_multi_line = b'parm'
            else:
                context_multi_line = b''

            if context_parm.lower() == b'u':
                context_nurbs.setdefault(b'parm_u', []).extend([float_func(f) for f in line_split])
            elif context_parm.lower() == b'v':  # surfaces not supported yet
                context_nurbs.setdefault(b'parm_v', []).extend([float_func(f) for f in line_split])
            # else: # may want to support other parm's ?

        elif line_start == b'deg':
            context_nurbs[b'deg'] = [int(i) for i in line.split()[1:]]
        elif line_start == b'end':
            # Add the nurbs curve
            if context_object:
                context_nurbs[b'name'] = context_object
            nurbs.append(context_nurbs)
            context_nurbs = {}
            context_parm = b''

        ''' # How to use usemap? depricated?
        elif line_start == b'usema': # usemap or usemat
            context_image= line_value(line_split)
        '''

    file.close()
    time_new = time.time()
    print("%.4f sec" % (time_new - time_sub))
    time_sub = time_new

    print('\tloading materials and images...')
    create_materials(filepath, material_libs, unique_materials, unique_material_images, use_image_search)

    time_new = time.time()
    print("%.4f sec" % (time_new - time_sub))
    time_sub = time_new

    # deselect all
    if bpy.ops.object.select_all.poll():
        bpy.ops.object.select_all(action='DESELECT')

    scene = context.scene
#     scn.objects.selected = []
    new_objects = []  # put new objects here

    print('\tbuilding geometry...\n\tverts:%i faces:%i materials: %i smoothgroups:%i ...' % (len(verts_loc), len(faces), len(unique_materials), len(unique_smooth_groups)))
    # Split the mesh by objects/materials, may
    if use_split_objects or use_split_groups:
        SPLIT_OB_OR_GROUP = True
    else:
        SPLIT_OB_OR_GROUP = False

    for verts_loc_split, faces_split, unique_materials_split, dataname in split_mesh(verts_loc, faces, unique_materials, filepath, SPLIT_OB_OR_GROUP):
        # Create meshes from the data, warning 'vertex_groups' wont support splitting
        create_mesh(new_objects,
                    has_ngons,
                    use_ngons,
                    use_edges,
                    verts_loc_split,
                    verts_tex,
                    faces_split,
                    unique_materials_split,
                    unique_material_images,
                    unique_smooth_groups,
                    vertex_groups,
                    dataname,
                    )

    # nurbs support
    for context_nurbs in nurbs:
        create_nurbs(context_nurbs, verts_loc, new_objects)

    # Create new obj
    for obj in new_objects:
        base = scene.objects.link(obj)
        base.select = True

        # we could apply this anywhere before scaling.
        obj.matrix_world = global_matrix

    scene.update()

    axis_min = [1000000000] * 3
    axis_max = [-1000000000] * 3

    if global_clamp_size:
        # Get all object bounds
        for ob in new_objects:
            for v in ob.bound_box:
                for axis, value in enumerate(v):
                    if axis_min[axis] > value:
                        axis_min[axis] = value
                    if axis_max[axis] < value:
                        axis_max[axis] = value

        # Scale objects
        max_axis = max(axis_max[0] - axis_min[0], axis_max[1] - axis_min[1], axis_max[2] - axis_min[2])
        scale = 1.0

        while global_clamp_size < max_axis * scale:
            scale = scale / 10.0

        for obj in new_objects:
            obj.scale = scale, scale, scale

    time_new = time.time()

    print("finished importing: %r in %.4f sec." % (filepath, (time_new - time_main)))
    return {'FINISHED'}


# NOTES (all line numbers refer to 2.4x import_obj.py, not this file)
# check later: line 489
# can convert now: edge flags, edges: lines 508-528
# ngon (uses python module BPyMesh): 384-414
# NEXT clamp size: get bound box with RNA
# get back to l 140 (here)
# search image in bpy.config.textureDir - load_image
# replaced BPyImage.comprehensiveImageLoad with a simplified version that only checks additional directory specified, but doesn't search dirs recursively (obj_image_load)
# bitmask won't work? - 132
# uses bpy.sys.time()
