"""
Verify estimated pose by rendering the scene with the target object at the estimated position.
"""

import json
import os

import imageio
import numpy as np
import trimesh
from scipy.spatial.transform import Rotation as R
from trimesh.transformations import euler_matrix

import genesis as gs


def render_with_estimated_pose(
    output_dir: str,
    object_mesh_path: str,
    container_mesh_path: str,
    table_path: str = "../video_gen_assets/table.glb",
    use_icp_pose: bool = True,
    use_physics_pose: bool = False,
    use_physics_initial: bool = False,
    container_euler: list = None,
    pose_idx: int = None,
    wall_mode: bool = False,
    wall_x: float = -0.5,
    wall_height: float = 1.2,
    container_pos: list = None,
    object_scale: float = 1.0,
):
    """Render scene with target object at estimated pose."""

    pose_label = "estimated"

    if use_physics_pose or use_physics_initial:
        # Load physics-refined pose
        pose_path = os.path.join(output_dir, "physics_refinement", "refined_poses.json")
        with open(pose_path, "r") as f:
            pose_data = json.load(f)

        if pose_idx is not None:
            best_pose = pose_data["valid_poses"][pose_idx]
            print(f"Using physics pose at index {pose_idx}")
        else:
            best_pose = pose_data.get("best_pose")
        if best_pose is None:
            raise ValueError("No valid physics-refined pose found")

        if use_physics_initial:
            # Use initial pose (before physics settling)
            if "init_pos" not in best_pose:
                raise ValueError("Initial pose not stored. Re-run physics refinement.")
            tvec_w = np.array(best_pose["init_pos"])
            quat_wxyz = best_pose["init_quat_wxyz"]
            pose_label = "physics_initial"
            print("Using physics INITIAL pose (before settling)")
        else:
            # Use final pose (after physics settling)
            tvec_w = np.array(best_pose["pos"])
            quat_wxyz = best_pose["quat_wxyz"]
            pose_label = "physics_final"
            print("Using physics FINAL pose (after settling)")

        # Convert quaternion to rotation vector
        quat_xyzw = [quat_wxyz[1], quat_wxyz[2], quat_wxyz[3], quat_wxyz[0]]
        rvec_w = R.from_quat(quat_xyzw).as_rotvec()
        print(f"Stability: pos_drift={best_pose['pos_drift']:.4f}m, rot_drift={best_pose['rot_drift_deg']:.2f}°")
    else:
        # Load estimated pose
        pose_path = os.path.join(output_dir, "pose_estimation", "best_pose.json")
        with open(pose_path, "r") as f:
            pose_data = json.load(f)

        if use_icp_pose and "tvec_w_icp" in pose_data:
            tvec_w = np.array(pose_data["tvec_w_icp"])
            rvec_w = np.array(pose_data["rvec_w_icp"])
            print("Using ICP-refined pose")
        else:
            tvec_w = np.array(pose_data["tvec_w"])
            rvec_w = np.array(pose_data["rvec_w"])
            print("Using 3D-3D registration pose")

    print(f"Position: {tvec_w}")
    print(f"Rotation (rotvec): {rvec_w}")

    # Convert rotation vector to quaternion (scalar-first for Genesis)
    rot = R.from_rotvec(rvec_w)
    quat_xyzw = rot.as_quat()  # [x, y, z, w]
    quat_wxyz = np.array([quat_xyzw[3], quat_xyzw[0], quat_xyzw[1], quat_xyzw[2]])  # [w, x, y, z]

    # Load camera parameters
    cam_pose = np.load(os.path.join(output_dir, "cam_pose.npy"))
    intrinsic_K = np.load(os.path.join(output_dir, "intrinsic_K.npy"))

    # Extract camera position from pose matrix
    # cam_pose is camera-to-world transform (OpenCV convention: Z points into scene)
    cam_pos = cam_pose[:3, 3]

    # Camera Z axis in world frame (third column of rotation) points into the scene
    forward = cam_pose[:3, 2]

    # Lookat point is camera position + forward direction
    lookat = cam_pos + forward * 1.0  # Look 1 meter ahead

    print(f"Camera position: {cam_pos}")
    print(f"Camera forward: {forward}")
    print(f"Camera lookat: {lookat}")

    # Initialize Genesis
    gs.init(seed=0, precision="32", logging_level="warning")

    # Use same HDR environment + lighting as place_scene.py
    DEFAULT_HDR_PATH = os.environ.get(
        "DEMO_HDR_PATH",
        os.path.join(
            os.path.dirname(os.path.abspath(__file__)),
            "..", "video_gen_assets",
            "9286496a-b761-4bdf-9f08-7966281b9c69.hdr",
        ),
    )
    renderer_kwargs = {
        "env_radius": 200.0,
        "lights": [
            {"pos": (0, -70, 40), "color": (255.0, 255.0, 255.0),
             "radius": 7, "intensity": 0.42},
        ],
    }
    if os.path.exists(DEFAULT_HDR_PATH):
        renderer_kwargs["env_surface"] = gs.surfaces.Emission(
            emissive_texture=gs.textures.ImageTexture(
                image_path=DEFAULT_HDR_PATH,
                image_color=(0.5, 0.5, 0.5),
            )
        )

    scene = gs.Scene(
        sim_options=gs.options.SimOptions(dt=0.01, substeps=5, gravity=(0, 0, -9.8)),
        show_viewer=False,
        rigid_options=gs.options.RigidOptions(enable_collision=False),
        renderer=gs.renderers.RayTracer(**renderer_kwargs),
    )

    # Add camera with same parameters as original render
    cam = scene.add_camera(
        pos=tuple(cam_pos),
        lookat=tuple(lookat),
        res=(1200, 896),
        fov=50.0,
        GUI=False,
        spp=1024,
    )

    mat_rigid = gs.materials.Rigid()

    if wall_mode:
        # Wall-mounted scene (e.g., hanger_hooks)
        from place_scene import add_wall, DEFAULT_WALL_TEXTURE
        c_euler = container_euler if container_euler is not None else [-180, 0, 90]

        # Add wall
        if os.path.exists(DEFAULT_WALL_TEXTURE):
            add_wall(scene, wall_x, wall_x, -3, 3, height=3.0,
                     texture=DEFAULT_WALL_TEXTURE, wall_id=0)

        # Place container flush against wall at wall_height
        crx, cry, crz = np.deg2rad(c_euler)
        cmesh = trimesh.load(container_mesh_path, force="mesh")
        cmesh.apply_transform(euler_matrix(crx, cry, crz, "sxyz"))
        min_x = cmesh.bounds[0][0]
        container_x = wall_x - min_x
        container_entity = scene.add_entity(
            material=mat_rigid,
            morph=gs.morphs.Mesh(
                file=container_mesh_path,
                pos=[container_x, 0.0, wall_height],
                euler=c_euler,
                collision=False,
            ),
            surface=gs.surfaces.Plastic(),
        )
    else:
        # Table-mounted scene (default)
        scene.add_entity(
            material=mat_rigid,
            morph=gs.morphs.Mesh(
                file=table_path,
                pos=[0.0, 0.0, 0.485403],
                euler=[90, 0, 90],
                collision=False,
            ),
        )

        # Background wall (same as place_scene.py)
        DEFAULT_WALL_TEXTURE = os.environ.get(
            "DEMO_WALL_TEXTURE",
            os.path.join(
                os.path.dirname(os.path.abspath(__file__)),
                "..", "video_gen_assets", "wall-basecolor.jpg",
            ),
        )
        if os.path.exists(DEFAULT_WALL_TEXTURE):
            from place_scene import add_wall
            add_wall(scene, -0.345, -0.345, -3, 3,
                     texture=DEFAULT_WALL_TEXTURE, wall_id=0)

        c_euler = container_euler if container_euler is not None else [90, 0, 0]
        table_height = 0.7451
        if container_pos is not None:
            c_pos = list(container_pos)
            print(f"Container placed at pos={c_pos} (override)")
        else:
            crx, cry, crz = np.deg2rad(c_euler)
            cmesh = trimesh.load(container_mesh_path, force="mesh")
            cmesh.apply_transform(euler_matrix(crx, cry, crz, "sxyz"))
            container_z = table_height - cmesh.bounds[0][2]
            c_pos = [0.0, 0.0, container_z]
            print(f"Container auto-placed at z={container_z:.4f}")
        container_entity_kwargs = {
            "material": mat_rigid,
            "morph": gs.morphs.Mesh(
                file=container_mesh_path,
                pos=c_pos,
                euler=c_euler,
                collision=False,
            ),
        }
        # Match place_scene.py: only apply Metal surface to .obj files
        if container_mesh_path.endswith(".obj"):
            container_entity_kwargs["surface"] = gs.surfaces.Metal()
        container_entity = scene.add_entity(**container_entity_kwargs)

    # Add target object (mug) at estimated pose
    # Convert euler to degrees for Genesis
    euler_deg = rot.as_euler('xyz', degrees=True)

    target_mesh_kwargs = {
        "file": object_mesh_path,
        "pos": list(tvec_w),
        "quat": list(quat_wxyz),
        "collision": False,
    }
    if object_scale != 1.0:
        target_mesh_kwargs["scale"] = object_scale
    target_entity = scene.add_entity(
        material=mat_rigid,
        morph=gs.morphs.Mesh(**target_mesh_kwargs),
    )

    scene.build()

    # Render
    img, depth, seg, _ = cam.render(depth=True, segmentation=True)

    # Save outputs
    verify_dir = os.path.join(output_dir, "pose_verification")
    os.makedirs(verify_dir, exist_ok=True)

    output_path = os.path.join(verify_dir, f"rendered_at_{pose_label}_pose.png")
    imageio.imwrite(output_path, img)
    print(f"\nSaved verification render: {output_path}")

    # Also save a comparison side-by-side
    goal_image_path = os.path.join(output_dir, "image_goal.png")
    if os.path.exists(goal_image_path):
        goal_img = imageio.imread(goal_image_path)

        # Resize if needed
        if goal_img.shape[:2] != img.shape[:2]:
            from PIL import Image
            goal_pil = Image.fromarray(goal_img)
            goal_pil = goal_pil.resize((img.shape[1], img.shape[0]), Image.BILINEAR)
            goal_img = np.array(goal_pil)

        # Create side-by-side comparison
        comparison = np.concatenate([goal_img[:, :, :3], img], axis=1)
        comparison_path = os.path.join(verify_dir, "comparison_goal_vs_estimated.png")
        imageio.imwrite(comparison_path, comparison)
        print(f"Saved comparison: {comparison_path}")

    return img


def main():
    import argparse

    parser = argparse.ArgumentParser(description="Verify estimated pose by rendering")
    parser.add_argument("--output_dir", type=str, default="./outputs/mug_tree_goal",
                        help="Output directory with pipeline outputs")
    parser.add_argument("--object_mesh_path", type=str, default="./assets/mug_0.glb",
                        help="Path to target object mesh")
    parser.add_argument("--container_mesh_path", type=str,
                        default="./assets/metal_mug_holder/metal_mug_holder.obj",
                        help="Path to container mesh")
    parser.add_argument("--table_path", type=str,
                        default="../video_gen_assets/table.glb",
                        help="Path to table mesh")
    parser.add_argument("--no_icp", action="store_true",
                        help="Use pose before ICP refinement")
    parser.add_argument("--physics", action="store_true",
                        help="Use physics-refined final pose (after settling)")
    parser.add_argument("--physics_initial", action="store_true",
                        help="Use physics initial pose (before settling)")
    parser.add_argument("--container_euler", type=float, nargs=3, default=None,
                        help="Container euler angles (default: [90, 0, 0])")
    parser.add_argument("--pose_idx", type=int, default=None,
                        help="Index into valid_poses (default: use best_pose)")
    parser.add_argument("--container_pos", type=float, nargs=3, default=None,
                        help="Override container position [x y z] (default: auto-compute from mesh bounds)")
    parser.add_argument("--wall", action="store_true",
                        help="Use wall-mounted scene instead of table")
    parser.add_argument("--wall_x", type=float, default=-0.5,
                        help="X position of wall plane (default: -0.5)")
    parser.add_argument("--wall_height", type=float, default=1.2,
                        help="Z height to mount container on wall (default: 1.2)")
    parser.add_argument("--object_scale", type=float, default=1.0,
                        help="Scale factor for target object mesh (default: 1.0)")

    args = parser.parse_args()

    render_with_estimated_pose(
        output_dir=args.output_dir,
        object_mesh_path=args.object_mesh_path,
        container_mesh_path=args.container_mesh_path,
        table_path=args.table_path,
        use_icp_pose=not args.no_icp,
        use_physics_pose=args.physics,
        use_physics_initial=args.physics_initial,
        container_euler=args.container_euler,
        pose_idx=args.pose_idx,
        wall_mode=args.wall,
        wall_x=args.wall_x,
        wall_height=args.wall_height,
        container_pos=args.container_pos,
        object_scale=args.object_scale,
    )


if __name__ == "__main__":
    main()