# Copyright (c) 2022-2024, The Isaac Lab Project Developers.
# All rights reserved.
#
# SPDX-License-Identifier: BSD-3-Clause


from dataclasses import MISSING

import omni.isaac.lab.sim as sim_utils
from omni.isaac.lab.actuators.actuator_cfg import ImplicitActuatorCfg
from omni.isaac.lab.assets import ArticulationCfg, AssetBaseCfg
from omni.isaac.lab.envs import ManagerBasedRLEnvCfg
from omni.isaac.lab.managers import EventTermCfg as EventTerm
from omni.isaac.lab.managers import ObservationGroupCfg as ObsGroup
from omni.isaac.lab.managers import ObservationTermCfg as ObsTerm
from omni.isaac.lab.managers import RewardTermCfg as RewTerm
from omni.isaac.lab.managers import SceneEntityCfg
from omni.isaac.lab.managers import TerminationTermCfg as DoneTerm
from omni.isaac.lab.scene import InteractiveSceneCfg
from omni.isaac.lab.sensors import FrameTransformerCfg
from omni.isaac.lab.sensors.frame_transformer import OffsetCfg
from omni.isaac.lab.utils import configclass
from omni.isaac.lab.utils.assets import ISAAC_NUCLEUS_DIR

from . import mdp

##
# Pre-defined configs
##
from omni.isaac.lab.markers.config import FRAME_MARKER_CFG  # isort: skip


FRAME_MARKER_SMALL_CFG = FRAME_MARKER_CFG.copy()
FRAME_MARKER_SMALL_CFG.markers["frame"].scale = (0.10, 0.10, 0.10)


##
# Scene definition
##


@configclass
class CabinetSceneCfg(InteractiveSceneCfg):
    """Configuration for the cabinet scene with a robot and a cabinet.

    This is the abstract base implementation, the exact scene is defined in the derived classes
    which need to set the robot and end-effector frames
    """

    # robots, Will be populated by agent env cfg
    robot: ArticulationCfg = MISSING
    # End-effector, Will be populated by agent env cfg
    ee_frame: FrameTransformerCfg = MISSING

    cabinet = ArticulationCfg(
        prim_path="{ENV_REGEX_NS}/Cabinet",
        spawn=sim_utils.UsdFileCfg(
            usd_path=f"{ISAAC_NUCLEUS_DIR}/Props/Sektion_Cabinet/sektion_cabinet_instanceable.usd",
            activate_contact_sensors=False,
        ),
        init_state=ArticulationCfg.InitialStateCfg(
            pos=(0.8, 0, 0.4),
            rot=(0.0, 0.0, 0.0, 1.0),
            joint_pos={
                "door_left_joint": 0.0,
                "door_right_joint": 0.0,
                "drawer_bottom_joint": 0.0,
                "drawer_top_joint": 0.0,
            },
        ),
        actuators={
            "drawers": ImplicitActuatorCfg(
                joint_names_expr=["drawer_top_joint", "drawer_bottom_joint"],
                effort_limit=87.0,
                velocity_limit=100.0,
                stiffness=10.0,
                damping=1.0,
            ),
            "doors": ImplicitActuatorCfg(
                joint_names_expr=["door_left_joint", "door_right_joint"],
                effort_limit=87.0,
                velocity_limit=100.0,
                stiffness=10.0,
                damping=2.5,
            ),
        },
    )

    # Frame definitions for the cabinet.
    cabinet_frame = FrameTransformerCfg(
        prim_path="{ENV_REGEX_NS}/Cabinet/sektion",
        debug_vis=True,
        visualizer_cfg=FRAME_MARKER_SMALL_CFG.replace(prim_path="/Visuals/CabinetFrameTransformer"),
        target_frames=[
            FrameTransformerCfg.FrameCfg(
                prim_path="{ENV_REGEX_NS}/Cabinet/drawer_handle_top",
                name="drawer_handle_top",
                offset=OffsetCfg(
                    pos=(0.305, 0.0, 0.01),
                    rot=(0.5, 0.5, -0.5, -0.5),  # align with end-effector frame
                ),
            ),
        ],
    )

    # plane
    plane = AssetBaseCfg(
        prim_path="/World/GroundPlane",
        init_state=AssetBaseCfg.InitialStateCfg(),
        spawn=sim_utils.GroundPlaneCfg(),
        collision_group=-1,
    )

    # lights
    light = AssetBaseCfg(
        prim_path="/World/light",
        spawn=sim_utils.DomeLightCfg(color=(0.75, 0.75, 0.75), intensity=3000.0),
    )


##
# MDP settings
##


@configclass
class CommandsCfg:
    """Command terms for the MDP."""

    null_command = mdp.NullCommandCfg()


@configclass
class ActionsCfg:
    """Action specifications for the MDP."""

    body_joint_pos: mdp.JointPositionActionCfg = MISSING
    finger_joint_pos: mdp.BinaryJointPositionActionCfg = MISSING


@configclass
class ObservationsCfg:
    """Observation specifications for the MDP."""

    @configclass
    class PolicyCfg(ObsGroup):
        """Observations for policy group."""

        joint_pos = ObsTerm(func=mdp.joint_pos_rel)
        joint_vel = ObsTerm(func=mdp.joint_vel_rel)
        cabinet_joint_pos = ObsTerm(
            func=mdp.joint_pos_rel,
            params={"asset_cfg": SceneEntityCfg("cabinet", joint_names=["drawer_top_joint"])},
        )
        cabinet_joint_vel = ObsTerm(
            func=mdp.joint_vel_rel,
            params={"asset_cfg": SceneEntityCfg("cabinet", joint_names=["drawer_top_joint"])},
        )
        rel_ee_drawer_distance = ObsTerm(func=mdp.rel_ee_drawer_distance)

        actions = ObsTerm(func=mdp.last_action)

        def __post_init__(self):
            self.enable_corruption = True
            self.concatenate_terms = True

    # observation groups
    policy: PolicyCfg = PolicyCfg()


@configclass
class EventCfg:
    """Configuration for events."""

    robot_physics_material = EventTerm(
        func=mdp.randomize_rigid_body_material,
        mode="startup",
        params={
            "asset_cfg": SceneEntityCfg("robot", body_names=".*"),
            "static_friction_range": (0.8, 1.25),
            "dynamic_friction_range": (0.8, 1.25),
            "restitution_range": (0.0, 0.0),
            "num_buckets": 16,
        },
    )

    cabinet_physics_material = EventTerm(
        func=mdp.randomize_rigid_body_material,
        mode="startup",
        params={
            "asset_cfg": SceneEntityCfg("cabinet", body_names="drawer_handle_top"),
            "static_friction_range": (1.0, 1.25),
            "dynamic_friction_range": (1.25, 1.5),
            "restitution_range": (0.0, 0.0),
            "num_buckets": 16,
        },
    )

    reset_all = EventTerm(func=mdp.reset_scene_to_default, mode="reset")

    reset_robot_joints = EventTerm(
        func=mdp.reset_joints_by_offset,
        mode="reset",
        params={
            "position_range": (-0.1, 0.1),
            "velocity_range": (0.0, 0.0),
        },
    )


@configclass
class RewardsCfg:
    """Reward terms for the MDP."""

    # 1. Approach the handle
    approach_ee_handle = RewTerm(func=mdp.approach_ee_handle, weight=2.0, params={"threshold": 0.2})
    align_ee_handle = RewTerm(func=mdp.align_ee_handle, weight=0.5)

    # 2. Grasp the handle
    approach_gripper_handle = RewTerm(func=mdp.approach_gripper_handle, weight=5.0, params={"offset": MISSING})
    align_grasp_around_handle = RewTerm(func=mdp.align_grasp_around_handle, weight=0.125)
    grasp_handle = RewTerm(
        func=mdp.grasp_handle,
        weight=0.5,
        params={
            "threshold": 0.03,
            "open_joint_pos": MISSING,
            "asset_cfg": SceneEntityCfg("robot", joint_names=MISSING),
        },
    )

    # 3. Open the drawer
    open_drawer_bonus = RewTerm(
        func=mdp.open_drawer_bonus,
        weight=7.5,
        params={"asset_cfg": SceneEntityCfg("cabinet", joint_names=["drawer_top_joint"])},
    )
    multi_stage_open_drawer = RewTerm(
        func=mdp.multi_stage_open_drawer,
        weight=1.0,
        params={"asset_cfg": SceneEntityCfg("cabinet", joint_names=["drawer_top_joint"])},
    )

    # 4. Penalize actions for cosmetic reasons
    action_rate_l2 = RewTerm(func=mdp.action_rate_l2, weight=-1e-2)
    joint_vel = RewTerm(func=mdp.joint_vel_l2, weight=-0.0001)


@configclass
class TerminationsCfg:
    """Termination terms for the MDP."""

    time_out = DoneTerm(func=mdp.time_out, time_out=True)


##
# Environment configuration
##


@configclass
class CabinetEnvCfg(ManagerBasedRLEnvCfg):
    """Configuration for the cabinet environment."""

    # Scene settings
    scene: CabinetSceneCfg = CabinetSceneCfg(num_envs=4096, env_spacing=2.0)
    # Basic settings
    observations: ObservationsCfg = ObservationsCfg()
    actions: ActionsCfg = ActionsCfg()
    commands: CommandsCfg = CommandsCfg()
    # MDP settings
    rewards: RewardsCfg = RewardsCfg()
    terminations: TerminationsCfg = TerminationsCfg()
    events: EventCfg = EventCfg()

    def __post_init__(self):
        """Post initialization."""
        # general settings
        self.decimation = 1
        self.episode_length_s = 8.0
        self.viewer.eye = (-2.0, 2.0, 2.0)
        self.viewer.lookat = (0.8, 0.0, 0.5)
        # simulation settings
        self.sim.dt = 1 / 60  # 60Hz
        self.sim.physx.bounce_threshold_velocity = 0.2
        self.sim.physx.bounce_threshold_velocity = 0.01
        self.sim.physx.friction_correlation_distance = 0.00625
