# Copyright (c) Meta Platforms, Inc. and affiliates.
# All rights reserved.
#
# This source code is licensed under the BSD-style license found in the
# LICENSE file in the root directory of this source tree.


import contextlib
import copy
import os
import unittest

import torch
import torchvision
from pytorch3d.implicitron.dataset.implicitron_dataset import ImplicitronDataset
from pytorch3d.implicitron.dataset.visualize import get_implicitron_sequence_pointcloud
from pytorch3d.implicitron.tools.point_cloud_utils import render_point_cloud_pytorch3d
from pytorch3d.vis.plotly_vis import plot_scene
from visdom import Visdom

if os.environ.get("FB_TEST", False):
    from .common_resources import get_skateboard_data
else:
    from common_resources import get_skateboard_data


class TestDatasetVisualize(unittest.TestCase):
    def setUp(self):
        if os.environ.get("INSIDE_RE_WORKER") is not None:
            raise unittest.SkipTest("Visdom not available")
        category = "skateboard"
        stack = contextlib.ExitStack()
        dataset_root, path_manager = stack.enter_context(get_skateboard_data())
        self.addCleanup(stack.close)
        frame_file = os.path.join(dataset_root, category, "frame_annotations.jgz")
        sequence_file = os.path.join(dataset_root, category, "sequence_annotations.jgz")
        self.image_size = 256
        self.datasets = {
            "simple": ImplicitronDataset(
                frame_annotations_file=frame_file,
                sequence_annotations_file=sequence_file,
                dataset_root=dataset_root,
                image_height=self.image_size,
                image_width=self.image_size,
                box_crop=True,
                load_point_clouds=True,
                path_manager=path_manager,
            ),
            "nonsquare": ImplicitronDataset(
                frame_annotations_file=frame_file,
                sequence_annotations_file=sequence_file,
                dataset_root=dataset_root,
                image_height=self.image_size,
                image_width=self.image_size // 2,
                box_crop=True,
                load_point_clouds=True,
                path_manager=path_manager,
            ),
            "nocrop": ImplicitronDataset(
                frame_annotations_file=frame_file,
                sequence_annotations_file=sequence_file,
                dataset_root=dataset_root,
                image_height=self.image_size,
                image_width=self.image_size // 2,
                box_crop=False,
                load_point_clouds=True,
                path_manager=path_manager,
            ),
        }
        self.datasets.update(
            {
                k + "_newndc": _change_annotations_to_new_ndc(dataset)
                for k, dataset in self.datasets.items()
            }
        )
        self.visdom = Visdom()
        if not self.visdom.check_connection():
            print("Visdom server not running! Disabling visdom visualizations.")
            self.visdom = None

    def _render_one_pointcloud(self, point_cloud, cameras, render_size):
        (_image_render, _, _) = render_point_cloud_pytorch3d(
            cameras,
            point_cloud,
            render_size=render_size,
            point_radius=1e-2,
            topk=10,
            bg_color=0.0,
        )
        return _image_render.clamp(0.0, 1.0)

    def test_one(self):
        """Test dataset visualization."""
        if os.environ.get("INSIDE_RE_WORKER") is not None:
            raise unittest.SkipTest("Visdom not available")
        for max_frames in (16, -1):
            for load_dataset_point_cloud in (True, False):
                for dataset_key in self.datasets:
                    self._gen_and_render_pointcloud(
                        max_frames, load_dataset_point_cloud, dataset_key
                    )

    def _gen_and_render_pointcloud(
        self, max_frames, load_dataset_point_cloud, dataset_key
    ):
        dataset = self.datasets[dataset_key]
        # load the point cloud of the first sequence
        sequence_show = list(dataset.seq_annots.keys())[0]
        device = torch.device("cuda:0")

        point_cloud, sequence_frame_data = get_implicitron_sequence_pointcloud(
            dataset,
            sequence_name=sequence_show,
            mask_points=True,
            max_frames=max_frames,
            num_workers=10,
            load_dataset_point_cloud=load_dataset_point_cloud,
        )

        # render on gpu
        point_cloud = point_cloud.to(device)
        cameras = sequence_frame_data.camera.to(device)

        # render the point_cloud from the viewpoint of loaded cameras
        images_render = torch.cat(
            [
                self._render_one_pointcloud(
                    point_cloud,
                    cameras[frame_i],
                    (
                        dataset.image_height,
                        dataset.image_width,
                    ),
                )
                for frame_i in range(len(cameras))
            ]
        ).cpu()
        images_gt_and_render = torch.cat(
            [sequence_frame_data.image_rgb, images_render], dim=3
        )

        imfile = os.path.join(
            os.path.split(os.path.abspath(__file__))[0],
            "test_dataset_visualize"
            + f"_max_frames={max_frames}"
            + f"_load_pcl={load_dataset_point_cloud}.png",
        )
        print(f"Exporting image {imfile}.")
        torchvision.utils.save_image(images_gt_and_render, imfile, nrow=2)

        if self.visdom is not None:
            test_name = f"{max_frames}_{load_dataset_point_cloud}_{dataset_key}"
            self.visdom.images(
                images_gt_and_render,
                env="test_dataset_visualize",
                win=f"pcl_renders_{test_name}",
                opts={"title": f"pcl_renders_{test_name}"},
            )
            plotlyplot = plot_scene(
                {
                    "scene_batch": {
                        "cameras": cameras,
                        "point_cloud": point_cloud,
                    }
                },
                camera_scale=1.0,
                pointcloud_max_points=10000,
                pointcloud_marker_size=1.0,
            )
            self.visdom.plotlyplot(
                plotlyplot,
                env="test_dataset_visualize",
                win=f"pcl_{test_name}",
            )


def _change_annotations_to_new_ndc(dataset):
    dataset = copy.deepcopy(dataset)
    for frame in dataset.frame_annots:
        vp = frame["frame_annotation"].viewpoint
        vp.intrinsics_format = "ndc_isotropic"
        # this assume the focal length to be equal on x and y (ok for a test)
        max_flength = max(vp.focal_length)
        vp.principal_point = (
            vp.principal_point[0] * max_flength / vp.focal_length[0],
            vp.principal_point[1] * max_flength / vp.focal_length[1],
        )
        vp.focal_length = (
            max_flength,
            max_flength,
        )

    return dataset
