node_wrangler.py

        option = self.option
        active = nodes.active
        if option == 'FROM_ACTIVE':
            if active:
                src_label = active.label
                for node in [n for n in nodes if n.select and nodes.active != n]:
                    node.label = src_label
        elif option == 'FROM_NODE':
            selected = [n for n in nodes if n.select]
            for node in selected:
                for input in node.inputs:
                    if input.links:
                        src = input.links[0].from_node
                        node.label = src.label
                        break
        elif option == 'FROM_SOCKET':
            selected = [n for n in nodes if n.select]
            for node in selected:
                for input in node.inputs:
                    if input.links:
                        src = input.links[0].from_socket
                        node.label = src.name
                        break

        return {'FINISHED'}


class NWClearLabel(Operator, NWBase):
    bl_idname = "node.nw_clear_label"
    bl_label = "Clear Label"
    bl_options = {'REGISTER', 'UNDO'}

    option: BoolProperty()

    def execute(self, context):
        nodes, links = get_nodes_links(context)
        for node in [n for n in nodes if n.select]:
            node.label = ''

        return {'FINISHED'}

    def invoke(self, context, event):
        if self.option:
            return self.execute(context)
        else:
            return context.window_manager.invoke_confirm(self, event)


class NWModifyLabels(Operator, NWBase):
    """Modify Labels of all selected nodes"""
    bl_idname = "node.nw_modify_labels"
    bl_label = "Modify Labels"
    bl_options = {'REGISTER', 'UNDO'}

    prepend: StringProperty(
        name="Add to Beginning"
    )
    append: StringProperty(
        name="Add to End"
    )
    replace_from: StringProperty(
        name="Text to Replace"
    )
    replace_to: StringProperty(
        name="Replace with"
    )

    def execute(self, context):
        nodes, links = get_nodes_links(context)
        for node in [n for n in nodes if n.select]:
            node.label = self.prepend + node.label.replace(self.replace_from, self.replace_to) + self.append

        return {'FINISHED'}

    def invoke(self, context, event):
        self.prepend = ""
        self.append = ""
        self.remove = ""
        return context.window_manager.invoke_props_dialog(self)


class NWAddTextureSetup(Operator, NWBase):
    bl_idname = "node.nw_add_texture"
    bl_label = "Texture Setup"
    bl_description = "Add Texture Node Setup to Selected Shaders"
    bl_options = {'REGISTER', 'UNDO'}

    add_mapping: BoolProperty(name="Add Mapping Nodes", description="Create coordinate and mapping nodes for the texture (ignored for selected texture nodes)", default=True)

    @classmethod
    def poll(cls, context):
        valid = False
        if nw_check(context):
            space = context.space_data
            if space.tree_type == 'ShaderNodeTree':
                valid = True
        return valid

    def execute(self, context):
        nodes, links = get_nodes_links(context)
        shader_types = [x[1] for x in shaders_shader_nodes_props if x[1] not in {'MIX_SHADER', 'ADD_SHADER'}]
        texture_types = [x[1] for x in shaders_texture_nodes_props]
        selected_nodes = [n for n in nodes if n.select]
        for t_node in selected_nodes:
            valid = False
            input_index = 0
            if t_node.inputs:
                for index, i in enumerate(t_node.inputs):
                    if not i.is_linked:
                        valid = True
                        input_index = index
                        break
            if valid:
                locx = t_node.location.x
                locy = t_node.location.y - t_node.dimensions.y/2

                xoffset = [500, 700]
                is_texture = False
                if t_node.type in texture_types + ['MAPPING']:
                    xoffset = [290, 500]
                    is_texture = True

                coordout = 2
                image_type = 'ShaderNodeTexImage'

                if (t_node.type in texture_types and t_node.type != 'TEX_IMAGE') or (t_node.type == 'BACKGROUND'):
                    coordout = 0  # image texture uses UVs, procedural textures and Background shader use Generated
                    if t_node.type == 'BACKGROUND':
                        image_type = 'ShaderNodeTexEnvironment'

                if not is_texture:
                    tex = nodes.new(image_type)
                    tex.location = [locx - 200, locy + 112]
                    nodes.active = tex
                    links.new(tex.outputs[0], t_node.inputs[input_index])

                t_node.select = False
                if self.add_mapping or is_texture:
                    if t_node.type != 'MAPPING':
                        m = nodes.new('ShaderNodeMapping')
                        m.location = [locx - xoffset[0], locy + 141]
                        m.width = 240
                    else:
                        m = t_node
                    coord = nodes.new('ShaderNodeTexCoord')
                    coord.location = [locx - (200 if t_node.type == 'MAPPING' else xoffset[1]), locy + 124]

                    if not is_texture:
                        links.new(m.outputs[0], tex.inputs[0])
                        links.new(coord.outputs[coordout], m.inputs[0])
                    else:
                        nodes.active = m
                        links.new(m.outputs[0], t_node.inputs[input_index])
                        links.new(coord.outputs[coordout], m.inputs[0])
            else:
                self.report({'WARNING'}, "No free inputs for node: "+t_node.name)
        return {'FINISHED'}


class NWAddPrincipledSetup(Operator, NWBase, ImportHelper):
    bl_idname = "node.nw_add_textures_for_principled"
    bl_label = "Principled Texture Setup"
    bl_description = "Add Texture Node Setup for Principled BSDF"
    bl_options = {'REGISTER', 'UNDO'}

    directory: StringProperty(
        name='Directory',
        subtype='DIR_PATH',
        default='',
        description='Folder to search in for image files'
    )
    files: CollectionProperty(
        type=bpy.types.OperatorFileListElement,
        options={'HIDDEN', 'SKIP_SAVE'}
    )

    relative_path: BoolProperty(
        name='Relative Path',
        description='Select the file relative to the blend file',
        default=True
    )

    order = [
        "filepath",
        "files",
    ]

    def draw(self, context):
        layout = self.layout
        layout.alignment = 'LEFT'

        layout.prop(self, 'relative_path')

    @classmethod
    def poll(cls, context):
        valid = False
        if nw_check(context):
            space = context.space_data
            if space.tree_type == 'ShaderNodeTree':
                valid = True
        return valid

    def execute(self, context):
        # Check if everything is ok
        if not self.directory:
            self.report({'INFO'}, 'No Folder Selected')
            return {'CANCELLED'}
        if not self.files[:]:
            self.report({'INFO'}, 'No Files Selected')
            return {'CANCELLED'}

        nodes, links = get_nodes_links(context)
        active_node = nodes.active
        if not (active_node and active_node.bl_idname == 'ShaderNodeBsdfPrincipled'):
            self.report({'INFO'}, 'Select Principled BSDF')
            return {'CANCELLED'}

        # Helper_functions
        def split_into__components(fname):
            # Split filename into components
            # 'WallTexture_diff_2k.002.jpg' -> ['Wall', 'Texture', 'diff', 'k']
            # Remove extension
            fname = path.splitext(fname)[0]
            # Remove digits
            fname = ''.join(i for i in fname if not i.isdigit())
            # Separate CamelCase by space
            fname = re.sub("([a-z])([A-Z])","\g<1> \g<2>",fname)
            # Replace common separators with SPACE
            seperators = ['_', '.', '-', '__', '--', '#']
            for sep in seperators:
                fname = fname.replace(sep, ' ')

            components = fname.split(' ')
            components = [c.lower() for c in components]
            return components

        # Filter textures names for texturetypes in filenames
        # [Socket Name, [abbreviations and keyword list], Filename placeholder]
        tags = context.preferences.addons[__name__].preferences.principled_tags
        normal_abbr = tags.normal.split(' ')
        bump_abbr = tags.bump.split(' ')
        gloss_abbr = tags.gloss.split(' ')
        rough_abbr = tags.rough.split(' ')
        socketnames = [
        ['Displacement', tags.displacement.split(' '), None],
        ['Base Color', tags.base_color.split(' '), None],
        ['Subsurface Color', tags.sss_color.split(' '), None],
        ['Metallic', tags.metallic.split(' '), None],
        ['Specular', tags.specular.split(' '), None],
        ['Roughness', rough_abbr + gloss_abbr, None],
        ['Normal', normal_abbr + bump_abbr, None],
        ]

        # Look through texture_types and set value as filename of first matched file
        def match_files_to_socket_names():
            for sname in socketnames:
                for file in self.files:
                    fname = file.name
                    filenamecomponents = split_into__components(fname)
                    matches = set(sname[1]).intersection(set(filenamecomponents))
                    # TODO: ignore basename (if texture is named "fancy_metal_nor", it will be detected as metallic map, not normal map)
                    if matches:
                        sname[2] = fname
                        break

        match_files_to_socket_names()
        # Remove socketnames without found files
        socketnames = [s for s in socketnames if s[2]
                       and path.exists(self.directory+s[2])]
        if not socketnames:
            self.report({'INFO'}, 'No matching images found')
            print('No matching images found')
            return {'CANCELLED'}

        # Don't override path earlier as os.path is used to check the absolute path
        import_path = self.directory
        if self.relative_path:
            if bpy.data.filepath:
                import_path = bpy.path.relpath(self.directory)
            else:
                self.report({'WARNING'}, 'Relative paths cannot be used with unsaved scenes!')
                print('Relative paths cannot be used with unsaved scenes!')

        # Add found images
        print('\nMatched Textures:')
        texture_nodes = []
        disp_texture = None
        normal_node = None
        roughness_node = None
        for i, sname in enumerate(socketnames):
            print(i, sname[0], sname[2])

            # DISPLACEMENT NODES
            if sname[0] == 'Displacement':
                disp_texture = nodes.new(type='ShaderNodeTexImage')
                img = bpy.data.images.load(path.join(import_path, sname[2]))
                disp_texture.image = img
                disp_texture.label = 'Displacement'
                if disp_texture.image:
                    disp_texture.image.colorspace_settings.is_data = True

                # Add displacement offset nodes
                disp_node = nodes.new(type='ShaderNodeDisplacement')
                disp_node.location = active_node.location + Vector((0, -560))
                link = links.new(disp_node.inputs[0], disp_texture.outputs[0])

                # TODO Turn on true displacement in the material
                # Too complicated for now

                # Find output node
                output_node = [n for n in nodes if n.bl_idname == 'ShaderNodeOutputMaterial']
                if output_node:
                    if not output_node[0].inputs[2].is_linked:
                        link = links.new(output_node[0].inputs[2], disp_node.outputs[0])

                continue

            if not active_node.inputs[sname[0]].is_linked:
                # No texture node connected -> add texture node with new image
                texture_node = nodes.new(type='ShaderNodeTexImage')
                img = bpy.data.images.load(path.join(import_path, sname[2]))
                texture_node.image = img

                # NORMAL NODES
                if sname[0] == 'Normal':
                    # Test if new texture node is normal or bump map
                    fname_components = split_into__components(sname[2])
                    match_normal = set(normal_abbr).intersection(set(fname_components))
                    match_bump = set(bump_abbr).intersection(set(fname_components))
                    if match_normal:
                        # If Normal add normal node in between
                        normal_node = nodes.new(type='ShaderNodeNormalMap')
                        link = links.new(normal_node.inputs[1], texture_node.outputs[0])
                    elif match_bump:
                        # If Bump add bump node in between
                        normal_node = nodes.new(type='ShaderNodeBump')
                        link = links.new(normal_node.inputs[2], texture_node.outputs[0])

                    link = links.new(active_node.inputs[sname[0]], normal_node.outputs[0])
                    normal_node_texture = texture_node

                elif sname[0] == 'Roughness':
                    # Test if glossy or roughness map
                    fname_components = split_into__components(sname[2])
                    match_rough = set(rough_abbr).intersection(set(fname_components))
                    match_gloss = set(gloss_abbr).intersection(set(fname_components))

                    if match_rough:
                        # If Roughness nothing to to
                        link = links.new(active_node.inputs[sname[0]], texture_node.outputs[0])

                    elif match_gloss:
                        # If Gloss Map add invert node
                        invert_node = nodes.new(type='ShaderNodeInvert')
                        link = links.new(invert_node.inputs[1], texture_node.outputs[0])

                        link = links.new(active_node.inputs[sname[0]], invert_node.outputs[0])
                        roughness_node = texture_node

                else:
                    # This is a simple connection Texture --> Input slot
                    link = links.new(active_node.inputs[sname[0]], texture_node.outputs[0])

                # Use non-color for all but 'Base Color' Textures
                if not sname[0] in ['Base Color'] and texture_node.image:
                    texture_node.image.colorspace_settings.is_data = True

            else:
                # If already texture connected. add to node list for alignment
                texture_node = active_node.inputs[sname[0]].links[0].from_node

            # This are all connected texture nodes
            texture_nodes.append(texture_node)
            texture_node.label = sname[0]

        if disp_texture:
            texture_nodes.append(disp_texture)

        # Alignment
        for i, texture_node in enumerate(texture_nodes):
            offset = Vector((-550, (i * -280) + 200))
            texture_node.location = active_node.location + offset

        if normal_node:
            # Extra alignment if normal node was added
            normal_node.location = normal_node_texture.location + Vector((300, 0))

        if roughness_node:
            # Alignment of invert node if glossy map
            invert_node.location = roughness_node.location + Vector((300, 0))

        # Add texture input + mapping
        mapping = nodes.new(type='ShaderNodeMapping')
        mapping.location = active_node.location + Vector((-1050, 0))
        if len(texture_nodes) > 1:
            # If more than one texture add reroute node in between
            reroute = nodes.new(type='NodeReroute')
            texture_nodes.append(reroute)
            tex_coords = Vector((texture_nodes[0].location.x, sum(n.location.y for n in texture_nodes)/len(texture_nodes)))
            reroute.location = tex_coords + Vector((-50, -120))
            for texture_node in texture_nodes:
                link = links.new(texture_node.inputs[0], reroute.outputs[0])
            link = links.new(reroute.inputs[0], mapping.outputs[0])
        else:
            link = links.new(texture_nodes[0].inputs[0], mapping.outputs[0])

        # Connect texture_coordiantes to mapping node
        texture_input = nodes.new(type='ShaderNodeTexCoord')
        texture_input.location = mapping.location + Vector((-200, 0))
        link = links.new(mapping.inputs[0], texture_input.outputs[2])

        # Create frame around tex coords and mapping
        frame = nodes.new(type='NodeFrame')
        frame.label = 'Mapping'
        mapping.parent = frame
        texture_input.parent = frame
        frame.update()

        # Create frame around texture nodes
        frame = nodes.new(type='NodeFrame')
        frame.label = 'Textures'
        for tnode in texture_nodes:
            tnode.parent = frame
        frame.update()

        # Just to be sure
        active_node.select = False
        nodes.update()
        links.update()
        force_update(context)
        return {'FINISHED'}


class NWAddReroutes(Operator, NWBase):
    """Add Reroute Nodes and link them to outputs of selected nodes"""
    bl_idname = "node.nw_add_reroutes"
    bl_label = "Add Reroutes"
    bl_description = "Add Reroutes to Outputs"
    bl_options = {'REGISTER', 'UNDO'}

    option: EnumProperty(
        name="option",
        items=[
            ('ALL', 'to all', 'Add to all outputs'),
            ('LOOSE', 'to loose', 'Add only to loose outputs'),
            ('LINKED', 'to linked', 'Add only to linked outputs'),
        ]
    )

    def execute(self, context):
        tree_type = context.space_data.node_tree.type
        option = self.option
        nodes, links = get_nodes_links(context)
        # output valid when option is 'all' or when 'loose' output has no links
        valid = False
        post_select = []  # nodes to be selected after execution
        # create reroutes and recreate links
        for node in [n for n in nodes if n.select]:
            if node.outputs:
                x = node.location.x
                y = node.location.y
                width = node.width
                # unhide 'REROUTE' nodes to avoid issues with location.y
                if node.type == 'REROUTE':
                    node.hide = False
                # When node is hidden - width_hidden not usable.
                # Hack needed to calculate real width
                if node.hide:
                    bpy.ops.node.select_all(action='DESELECT')
                    helper = nodes.new('NodeReroute')
                    helper.select = True
                    node.select = True
                    # resize node and helper to zero. Then check locations to calculate width
                    bpy.ops.transform.resize(value=(0.0, 0.0, 0.0))
                    width = 2.0 * (helper.location.x - node.location.x)
                    # restore node location
                    node.location = x, y
                    # delete helper
                    node.select = False
                    # only helper is selected now
                    bpy.ops.node.delete()
                x = node.location.x + width + 20.0
                if node.type != 'REROUTE':
                    y -= 35.0
                y_offset = -22.0
                loc = x, y
            reroutes_count = 0  # will be used when aligning reroutes added to hidden nodes
            for out_i, output in enumerate(node.outputs):
                pass_used = False  # initial value to be analyzed if 'R_LAYERS'
                # if node != 'R_LAYERS' - "pass_used" not needed, so set it to True
                if node.type != 'R_LAYERS':
                    pass_used = True
                else:  # if 'R_LAYERS' check if output represent used render pass
                    node_scene = node.scene
                    node_layer = node.layer
                    # If output - "Alpha" is analyzed - assume it's used. Not represented in passes.
                    if output.name == 'Alpha':
                        pass_used = True
                    else:
                        # check entries in global 'rl_outputs' variable
                        for rlo in rl_outputs:
                            if output.name in {rlo.output_name, rlo.exr_output_name}:
                                pass_used = getattr(node_scene.view_layers[node_layer], rlo.render_pass)
                                break
                if pass_used:
                    valid = ((option == 'ALL') or
                             (option == 'LOOSE' and not output.links) or
                             (option == 'LINKED' and output.links))
                    # Add reroutes only if valid, but offset location in all cases.
                    if valid:
                        n = nodes.new('NodeReroute')
                        nodes.active = n
                        for link in output.links:
                            links.new(n.outputs[0], link.to_socket)
                        links.new(output, n.inputs[0])
                        n.location = loc
                        post_select.append(n)
                    reroutes_count += 1
                    y += y_offset
                    loc = x, y
            # disselect the node so that after execution of script only newly created nodes are selected
            node.select = False
            # nicer reroutes distribution along y when node.hide
            if node.hide:
                y_translate = reroutes_count * y_offset / 2.0 - y_offset - 35.0
                for reroute in [r for r in nodes if r.select]:
                    reroute.location.y -= y_translate
            for node in post_select:
                node.select = True

        return {'FINISHED'}


class NWLinkActiveToSelected(Operator, NWBase):
    """Link active node to selected nodes basing on various criteria"""
    bl_idname = "node.nw_link_active_to_selected"
    bl_label = "Link Active Node to Selected"
    bl_options = {'REGISTER', 'UNDO'}

    replace: BoolProperty()
    use_node_name: BoolProperty()
    use_outputs_names: BoolProperty()

    @classmethod
    def poll(cls, context):
        valid = False
        if nw_check(context):
            if context.active_node is not None:
                if context.active_node.select:
                    valid = True
        return valid

    def execute(self, context):
        nodes, links = get_nodes_links(context)
        replace = self.replace
        use_node_name = self.use_node_name
        use_outputs_names = self.use_outputs_names
        active = nodes.active
        selected = [node for node in nodes if node.select and node != active]
        outputs = []  # Only usable outputs of active nodes will be stored here.
        for out in active.outputs:
            if active.type != 'R_LAYERS':
                outputs.append(out)
            else:
                # 'R_LAYERS' node type needs special handling.
                # outputs of 'R_LAYERS' are callable even if not seen in UI.
                # Only outputs that represent used passes should be taken into account
                # Check if pass represented by output is used.
                # global 'rl_outputs' list will be used for that
                for rlo in rl_outputs:
                    pass_used = False  # initial value. Will be set to True if pass is used
                    if out.name == 'Alpha':
                        # Alpha output is always present. Doesn't have representation in render pass. Assume it's used.
                        pass_used = True
                    elif out.name in {rlo.output_name, rlo.exr_output_name}:
                        # example 'render_pass' entry: 'use_pass_uv' Check if True in scene render layers
                        pass_used = getattr(active.scene.view_layers[active.layer], rlo.render_pass)
                        break
                if pass_used:
                    outputs.append(out)
        doit = True  # Will be changed to False when links successfully added to previous output.
        for out in outputs:
            if doit:
                for node in selected:
                    dst_name = node.name  # Will be compared with src_name if needed.
                    # When node has label - use it as dst_name
                    if node.label:
                        dst_name = node.label
                    valid = True  # Initial value. Will be changed to False if names don't match.
                    src_name = dst_name  # If names not used - this asignment will keep valid = True.
                    if use_node_name:
                        # Set src_name to source node name or label
                        src_name = active.name
                        if active.label:
                            src_name = active.label
                    elif use_outputs_names:
                        src_name = (out.name, )
                        for rlo in rl_outputs:
                            if out.name in {rlo.output_name, rlo.exr_output_name}:
                                src_name = (rlo.output_name, rlo.exr_output_name)
                    if dst_name not in src_name:
                        valid = False
                    if valid:
                        for input in node.inputs:
                            if input.type == out.type or node.type == 'REROUTE':
                                if replace or not input.is_linked:
                                    links.new(out, input)
                                    if not use_node_name and not use_outputs_names:
                                        doit = False
                                    break

        return {'FINISHED'}


class NWAlignNodes(Operator, NWBase):
    '''Align the selected nodes neatly in a row/column'''
    bl_idname = "node.nw_align_nodes"
    bl_label = "Align Nodes"
    bl_options = {'REGISTER', 'UNDO'}
    margin: IntProperty(name='Margin', default=50, description='The amount of space between nodes')

    def execute(self, context):
        nodes, links = get_nodes_links(context)
        margin = self.margin

        selection = []
        for node in nodes:
            if node.select and node.type != 'FRAME':
                selection.append(node)

        # If no nodes are selected, align all nodes
        active_loc = None
        if not selection:
            selection = nodes
        elif nodes.active in selection:
            active_loc = copy(nodes.active.location)  # make a copy, not a reference

        # Check if nodes should be laid out horizontally or vertically
        x_locs = [n.location.x + (n.dimensions.x / 2) for n in selection]  # use dimension to get center of node, not corner
        y_locs = [n.location.y - (n.dimensions.y / 2) for n in selection]
        x_range = max(x_locs) - min(x_locs)
        y_range = max(y_locs) - min(y_locs)
        mid_x = (max(x_locs) + min(x_locs)) / 2
        mid_y = (max(y_locs) + min(y_locs)) / 2
        horizontal = x_range > y_range

        # Sort selection by location of node mid-point
        if horizontal:
            selection = sorted(selection, key=lambda n: n.location.x + (n.dimensions.x / 2))
        else:
            selection = sorted(selection, key=lambda n: n.location.y - (n.dimensions.y / 2), reverse=True)

        # Alignment
        current_pos = 0
        for node in selection:
            current_margin = margin
            current_margin = current_margin * 0.5 if node.hide else current_margin  # use a smaller margin for hidden nodes

            if horizontal:
                node.location.x = current_pos
                current_pos += current_margin + node.dimensions.x
                node.location.y = mid_y + (node.dimensions.y / 2)
            else:
                node.location.y = current_pos
                current_pos -= (current_margin * 0.3) + node.dimensions.y  # use half-margin for vertical alignment
                node.location.x = mid_x - (node.dimensions.x / 2)

        # If active node is selected, center nodes around it
        if active_loc is not None:
            active_loc_diff = active_loc - nodes.active.location
            for node in selection:
                node.location += active_loc_diff
        else:  # Position nodes centered around where they used to be
            locs = ([n.location.x + (n.dimensions.x / 2) for n in selection]) if horizontal else ([n.location.y - (n.dimensions.y / 2) for n in selection])
            new_mid = (max(locs) + min(locs)) / 2
            for node in selection:
                if horizontal:
                    node.location.x += (mid_x - new_mid)
                else:
                    node.location.y += (mid_y - new_mid)

        return {'FINISHED'}


class NWSelectParentChildren(Operator, NWBase):
    bl_idname = "node.nw_select_parent_child"
    bl_label = "Select Parent or Children"
    bl_options = {'REGISTER', 'UNDO'}

    option: EnumProperty(
        name="option",
        items=(
            ('PARENT', 'Select Parent', 'Select Parent Frame'),
            ('CHILD', 'Select Children', 'Select members of selected frame'),
        )
    )

    def execute(self, context):
        nodes, links = get_nodes_links(context)
        option = self.option
        selected = [node for node in nodes if node.select]
        if option == 'PARENT':
            for sel in selected:
                parent = sel.parent
                if parent:
                    parent.select = True
        else:  # option == 'CHILD'
            for sel in selected:
                children = [node for node in nodes if node.parent == sel]
                for kid in children:
                    kid.select = True

        return {'FINISHED'}


class NWDetachOutputs(Operator, NWBase):
    """Detach outputs of selected node leaving inputs linked"""
    bl_idname = "node.nw_detach_outputs"
    bl_label = "Detach Outputs"
    bl_options = {'REGISTER', 'UNDO'}

    def execute(self, context):
        nodes, links = get_nodes_links(context)
        selected = context.selected_nodes
        bpy.ops.node.duplicate_move_keep_inputs()
        new_nodes = context.selected_nodes
        bpy.ops.node.select_all(action="DESELECT")
        for node in selected:
            node.select = True
        bpy.ops.node.delete_reconnect()
        for new_node in new_nodes:
            new_node.select = True
        bpy.ops.transform.translate('INVOKE_DEFAULT')

        return {'FINISHED'}


class NWLinkToOutputNode(Operator):
    """Link to Composite node or Material Output node"""
    bl_idname = "node.nw_link_out"
    bl_label = "Connect to Output"
    bl_options = {'REGISTER', 'UNDO'}

    @classmethod
    def poll(cls, context):
        valid = False
        if nw_check(context) and context.space_data.tree_type != 'GeometryNodeTree':
            if context.active_node is not None:
                for out in context.active_node.outputs:
                    if is_visible_socket(out):
                        valid = True
                        break
        return valid

    def execute(self, context):
        nodes, links = get_nodes_links(context)
        active = nodes.active
        output_node = None
        output_index = None
        tree_type = context.space_data.tree_type
        output_types_shaders = [x[1] for x in shaders_output_nodes_props]
        output_types_compo = ['COMPOSITE']
        output_types_blender_mat = ['OUTPUT']
        output_types_textures = ['OUTPUT']
        output_types = output_types_shaders + output_types_compo + output_types_blender_mat
        for node in nodes:
            if node.type in output_types:
                output_node = node
                break
        if not output_node:
            bpy.ops.node.select_all(action="DESELECT")
            if tree_type == 'ShaderNodeTree':
                output_node = nodes.new('ShaderNodeOutputMaterial')
            elif tree_type == 'CompositorNodeTree':
                output_node = nodes.new('CompositorNodeComposite')
            elif tree_type == 'TextureNodeTree':
                output_node = nodes.new('TextureNodeOutput')
            output_node.location.x = active.location.x + active.dimensions.x + 80
            output_node.location.y = active.location.y
        if (output_node and active.outputs):
            for i, output in enumerate(active.outputs):
                if is_visible_socket(output):
                    output_index = i
                    break
            for i, output in enumerate(active.outputs):
                if output.type == output_node.inputs[0].type and is_visible_socket(output):
                    output_index = i
                    break

            out_input_index = 0
            if tree_type == 'ShaderNodeTree':
                if active.outputs[output_index].name == 'Volume':
                    out_input_index = 1
                elif active.outputs[output_index].type != 'SHADER':  # connect to displacement if not a shader
                    out_input_index = 2
            links.new(active.outputs[output_index], output_node.inputs[out_input_index])

        force_update(context)  # viewport render does not update

        return {'FINISHED'}


class NWMakeLink(Operator, NWBase):
    """Make a link from one socket to another"""
    bl_idname = 'node.nw_make_link'
    bl_label = 'Make Link'
    bl_options = {'REGISTER', 'UNDO'}
    from_socket: IntProperty()
    to_socket: IntProperty()

    def execute(self, context):
        nodes, links = get_nodes_links(context)

        n1 = nodes[context.scene.NWLazySource]
        n2 = nodes[context.scene.NWLazyTarget]

        links.new(n1.outputs[self.from_socket], n2.inputs[self.to_socket])

        force_update(context)

        return {'FINISHED'}


class NWCallInputsMenu(Operator, NWBase):
    """Link from this output"""
    bl_idname = 'node.nw_call_inputs_menu'
    bl_label = 'Make Link'
    bl_options = {'REGISTER', 'UNDO'}
    from_socket: IntProperty()

    def execute(self, context):
        nodes, links = get_nodes_links(context)

        context.scene.NWSourceSocket = self.from_socket

        n1 = nodes[context.scene.NWLazySource]
        n2 = nodes[context.scene.NWLazyTarget]
        if len(n2.inputs) > 1:
            bpy.ops.wm.call_menu("INVOKE_DEFAULT", name=NWConnectionListInputs.bl_idname)
        elif len(n2.inputs) == 1:
            links.new(n1.outputs[self.from_socket], n2.inputs[0])
        return {'FINISHED'}


class NWAddSequence(Operator, NWBase, ImportHelper):
    """Add an Image Sequence"""
    bl_idname = 'node.nw_add_sequence'
    bl_label = 'Import Image Sequence'
    bl_options = {'REGISTER', 'UNDO'}

    directory: StringProperty(
        subtype="DIR_PATH"
    )
    filename: StringProperty(
        subtype="FILE_NAME"
    )
    files: CollectionProperty(
        type=bpy.types.OperatorFileListElement,
        options={'HIDDEN', 'SKIP_SAVE'}
    )

    def execute(self, context):
        nodes, links = get_nodes_links(context)
        directory = self.directory
        filename = self.filename
        files = self.files
        tree = context.space_data.node_tree

        # DEBUG
        # print ("\nDIR:", directory)
        # print ("FN:", filename)
        # print ("Fs:", list(f.name for f in files), '\n')

        if tree.type == 'SHADER':
            node_type = "ShaderNodeTexImage"
        elif tree.type == 'COMPOSITING':
            node_type = "CompositorNodeImage"
        else:
            self.report({'ERROR'}, "Unsupported Node Tree type!")
            return {'CANCELLED'}

        if not files[0].name and not filename:
            self.report({'ERROR'}, "No file chosen")
            return {'CANCELLED'}
        elif files[0].name and (not filename or not path.exists(directory+filename)):
            # User has selected multiple files without an active one, or the active one is non-existant
            filename = files[0].name

        if not path.exists(directory+filename):
            self.report({'ERROR'}, filename+" does not exist!")
            return {'CANCELLED'}

        without_ext = '.'.join(filename.split('.')[:-1])

        # if last digit isn't a number, it's not a sequence
        if not without_ext[-1].isdigit():
            self.report({'ERROR'}, filename+" does not seem to be part of a sequence")
            return {'CANCELLED'}


        extension = filename.split('.')[-1]
        reverse = without_ext[::-1] # reverse string

        count_numbers = 0
        for char in reverse:
            if char.isdigit():
                count_numbers += 1
            else:
                break

        without_num = without_ext[:count_numbers*-1]

        files = sorted(glob(directory + without_num + "[0-9]"*count_numbers + "." + extension))

        num_frames = len(files)

        nodes_list = [node for node in nodes]
        if nodes_list:
            nodes_list.sort(key=lambda k: k.location.x)
            xloc = nodes_list[0].location.x - 220  # place new nodes at far left
            yloc = 0
            for node in nodes:
                node.select = False
                yloc += node_mid_pt(node, 'y')
            yloc = yloc/len(nodes)
        else:
            xloc = 0
            yloc = 0

        name_with_hashes = without_num + "#"*count_numbers + '.' + extension

        bpy.ops.node.add_node('INVOKE_DEFAULT', use_transform=True, type=node_type)
        node = nodes.active
        node.label = name_with_hashes

        img = bpy.data.images.load(directory+(without_ext+'.'+extension))
        img.source = 'SEQUENCE'
        img.name = name_with_hashes
        node.image = img
        image_user = node.image_user if tree.type == 'SHADER' else node
        image_user.frame_offset = int(files[0][len(without_num)+len(directory):-1*(len(extension)+1)]) - 1  # separate the number from the file name of the first  file
        image_user.frame_duration = num_frames

        return {'FINISHED'}


class NWAddMultipleImages(Operator, NWBase, ImportHelper):
    """Add multiple images at once"""
    bl_idname = 'node.nw_add_multiple_images'
    bl_label = 'Open Selected Images'
    bl_options = {'REGISTER', 'UNDO'}
    directory: StringProperty(
        subtype="DIR_PATH"
    )
    files: CollectionProperty(
        type=bpy.types.OperatorFileListElement,
        options={'HIDDEN', 'SKIP_SAVE'}
    )

    def execute(self, context):
        nodes, links = get_nodes_links(context)

        xloc, yloc = context.region.view2d.region_to_view(context.area.width/2, context.area.height/2)

        if context.space_data.node_tree.type == 'SHADER':
            node_type = "ShaderNodeTexImage"
        elif context.space_data.node_tree.type == 'COMPOSITING':
            node_type = "CompositorNodeImage"
        else:
            self.report({'ERROR'}, "Unsupported Node Tree type!")
            return {'CANCELLED'}

        new_nodes = []
        for f in self.files:
            fname = f.name

            node = nodes.new(node_type)
            new_nodes.append(node)
            node.label = fname
            node.hide = True
            node.width_hidden = 100
            node.location.x = xloc
            node.location.y = yloc
            yloc -= 40

            img = bpy.data.images.load(self.directory+fname)
            node.image = img

        # shift new nodes up to center of tree
        list_size = new_nodes[0].location.y - new_nodes[-1].location.y
        for node in nodes:
            if node in new_nodes:
                node.select = True
                node.location.y += (list_size/2)
            else:
                node.select = False
        return {'FINISHED'}


class NWViewerFocus(bpy.types.Operator):