import os
import sys
import torch
import numpy as np

# from deodr import Camera, Scene3D
# from deodr.triangulated_mesh import TriMesh
# from deodr.pytorch.triangulated_mesh_pytorch import ColoredTriMeshPytorch
# from deodr.pytorch.differentiable_renderer_pytorch import Scene3DPytorch, CameraPytorch

sys.path.append(os.path.dirname(os.path.abspath(__file__)) + '/..')
from cloth3d.util import proj
from utils.data_utils import intrinsic, extrinsic, get_camera

class RenderCore:
    def __init__(self, max_depth=0, depth_scale=1):
        self.mesh = None
        self.depthScale = depth_scale
        self.scene = Scene3D()
        self.set_max_depth(max_depth)
		
    def set_mesh(self, vertices, faces):
        self.mesh = TriMesh(
            faces, vertices
        )  # we do a copy to avoid negative stride not support by Tensorflow
		
        object_center = vertices.mean(axis=0)
        object_radius = np.max(np.std(vertices, axis=0))
        self.camera_center = object_center + np.array([-0.5, 0, 5]) * object_radius
		
        self.scene.set_mesh(self.mesh)

    def set_max_depth(self, max_depth):
        self.scene.max_depth = max_depth
        self.scene.set_background_color([max_depth])

    def set_depth_scale(self, depth_scale):
        self.depthScale = depth_scale

    def set_image(self, width, height, intrinsic, extrinsic):
        self.width = width
        self.height = height
		
        # focal = None
        # if focal is None:
            # focal = 2 * self.width

        # rot = np.array([[1, 0, 0], [0, -1, 0], [0, 0, -1]])
        # trans = -rot.T.dot(self.camera_center)
        # intrinsic = np.array(
            # [[focal, 0, self.width / 2], [0, focal, self.height / 2], [0, 0, 1]]
        # )
        # extrinsic = np.column_stack((rot, trans))
		
        self.camera = Camera(
            extrinsic=extrinsic,
            intrinsic=intrinsic,
            width=self.width,
            height=self.height,
            distortion=None,
        )
        
    def render(self):
        depth_scale = 1 * self.depthScale
        depth = self.scene.render_depth(
            self.camera,
            depth_scale=depth_scale,
        )
        #depth = tf.clip_by_value(depth, 0, self.scene.max_depth)
        return depth


class Render:
    def __init__(self, max_depth=0, depth_scale=1, size=(640, 480)):
        self.render_core = RenderCore(max_depth=max_depth)
        self.size = size
        self.max_depth = max_depth

    def render(self, mesh, faces, cam):
        self.render_core.set_mesh(mesh, faces)
        self.render_core.set_image(self.size[0], self.size[1], intrinsic(), extrinsic(cam))
        depth = self.render_core.render()

        thresh = self.max_depth - 1
        mask = depth<thresh
        # dmin = depth.min()
        dmean = depth[mask].mean()
        # dmax = depth[mask].max()
        depth[mask] = depth[mask] - dmean
        depth[~mask] = 0.0
        mask = mask.astype(np.float32)

        return depth


from torch import nn
from pytorch3d.renderer import (
    look_at_view_transform,
    FoVPerspectiveCameras, 
    PerspectiveCameras,
    PointLights, 
    DirectionalLights, 
    Materials, 
    RasterizationSettings, 
    MeshRenderer, 
    MeshRasterizer,  
    SoftPhongShader,
    TexturesUV,
    TexturesVertex,
    HardPhongShader,
)
from pytorch3d.structures import Meshes
from pytorch3d.utils import cameras_from_opencv_projection


class DepthRenderer(nn.Module):
    def __init__(self) -> None:
         super().__init__()



    def forward(self, verts, faces, cam):
        # R, T = look_at_view_transform(2.7, 0, 0) 
        # cameras = FoVPerspectiveCameras(device='cuda', R=R, T=T)

        # ext = torch.tensor(extrinsic(cam).astype(np.float32), device='cuda')
        # ext = proj(cam)
        # fp = np.array([240 * (480 / 36), 320 * (640 / 36)], dtype=np.float32)
        img_size = np.array([480, 640], dtype=np.float32)
        # K = np.eye(4, dtype=np.float32)
        # K[:3,:3] = intrinsic()
        # K = torch.tensor(intrinsic()[None, :, :], device='cuda')
        # cameras = PerspectiveCameras(device='cuda', R=ext[None, :, :3], T=ext[None, :, 3], focal_length=1,)# principal_point=fp[None, :], image_size=img_size[None, :])

        # cameras = cameras_from_opencv_projection(R=ext[None, :, :3], tvec=ext[None, :, 3], camera_matrix=K, image_size=torch.tensor(img_size[None, :], device='cuda'))
        cameras, K = get_camera(cam, [480, 640], verts.get_device())

        raster_settings = RasterizationSettings(
                            image_size=(480, 640), 
                            blur_radius=0.0, 
                            faces_per_pixel=1, 
                            bin_size=0
                        )

        rasterizer = MeshRasterizer(
                    cameras=cameras, 
                    raster_settings=raster_settings
                )
        output = rasterizer(Meshes(verts[None,:,:], faces[None,:,:]))
        v2i = None #cameras.transform_points_screen(verts).round().to(torch.long)[:,:2]
        depth = output.zbuf[0,:,:,0]
        pix_to_face = output.pix_to_face[0,:,:,0]

        mask = depth != -1
        # dmin = depth.min()
        # dmean = depth[mask].mean()
        # dmax = depth[mask].max()
        # depth[mask] = depth[mask] - dmean
        # depth[~mask] = 0.0
        # mask = mask.astype(np.float32)

        # import plotly.express as ex
        # ex.imshow(depth.cpu().numpy()).show()

        return depth, mask, v2i, K, cameras, pix_to_face


class PoseRenderer(nn.Module):
    def __init__(self, device='cuda') -> None:
        super().__init__()
        colors = np.load('custom_data/pose_colors.npy')
        self.textures = TexturesVertex(verts_features=torch.from_numpy(colors).to(device)[None, :, :])
        self.cam = torch.tensor([0.0, 0.0, 1.0], device=device)


    def forward(self, verts: torch.Tensor, faces: torch.Tensor):
        cameras, K = get_camera(self.cam, [480, 640], verts.get_device())

        raster_settings = RasterizationSettings(
                            image_size=(480, 640), 
                            blur_radius=0.0, 
                            faces_per_pixel=1, 
                            bin_size=0
                        )
        
        renderer = MeshRenderer(
            rasterizer=MeshRasterizer(cameras=cameras, raster_settings=raster_settings),
            shader=HardPhongShader(device=verts.get_device(), cameras=cameras)
        )
        # create a pytorch3d vertex texture from the colors

        output = renderer(Meshes(verts[None,:,:], faces[None,:,:], textures=self.textures))


        return output