import json

import bmesh
import bpy
from bpy_extras.io_utils import ExportHelper
from bpy.props import FloatProperty, BoolProperty, FloatVectorProperty
from bpy.props import StringProperty
from bpy_extras import object_utils


class DumpMesh(bpy.types.Operator, ExportHelper):
    '''load json mesh from surfaces'''
    bl_idname = 'object.load_mesh'
    bl_label = 'Load Mesh'
    filename_ext = ".json"

    filter_glob = StringProperty(
        default="*.json",
        options={'HIDDEN'},
    )

    # generic transform props
    view_align = BoolProperty(
        name="Align to View",
        default=False,
    )
    location = FloatVectorProperty(
        name="Location",
        subtype='TRANSLATION',
    )
    rotation = FloatVectorProperty(
        name="Rotation",
        subtype='EULER',
    )

    @classmethod
    def poll(cls, context):
        return context.active_object is not None

    def execute(self, context):
        data = json.load(open(self.filepath, 'r'))
        mesh = bpy.data.meshes.new("Imported")

        bm = bmesh.new()

        for v_co in data['vertices']:
            bm.verts.new(v_co)

        for f_idx in data['faces']:
            bm.faces.new([bm.verts[i] for i in f_idx])

        bm.to_mesh(mesh)
        mesh.update()

        # add the mesh as an object into the scene with this utility module
        try:
            object_utils.object_data_add(context, mesh, operator=self)
        except:
            pass
        return {'FINISHED'}


def register():
    bpy.utils.register_class(DumpMesh)


def unregister():
    bpy.utils.unregister_class(DumpMesh)