"""T-Rex Pinocchio FK helpers (no dexmate_urdf / coal install required)."""

from __future__ import annotations

import sys
import types
from functools import lru_cache
from pathlib import Path
from typing import Callable

import numpy as np
import pinocchio as pin
from pinocchio.robot_wrapper import RobotWrapper

_TREX_ROOT = Path("/scratch1/home/zhicao/T-Rex")
_QS_SRC = _TREX_ROOT / "dataset_quickstart" / "src"
_DEXMATE_PKG = _TREX_ROOT / "hardware_code" / "third_party" / "dexmate-urdf" / "src"
_VEGA_DIR = _DEXMATE_PKG / "dexmate_urdf" / "robots" / "humanoid" / "vega_1"
VEGA_URDF = str(_VEGA_DIR / "vega_1.urdf")
VEGA_PKG = str(_VEGA_DIR)
VEGA_SRDF = str(_VEGA_DIR / "vega_1.srdf")

DEFAULT_TORSO = np.array([0.9, 1.57, 0.1])
DEFAULT_HEAD = np.array([0.28, 0.0, 0.0])

SHARPA_LEFT_HAND_JOINT_ORDER = [
    "left_thumb_CMC_FE",
    "left_thumb_CMC_AA",
    "left_thumb_MCP_FE",
    "left_thumb_MCP_AA",
    "left_thumb_IP",
    "left_index_MCP_FE",
    "left_index_MCP_AA",
    "left_index_PIP",
    "left_index_DIP",
    "left_middle_MCP_FE",
    "left_middle_MCP_AA",
    "left_middle_PIP",
    "left_middle_DIP",
    "left_ring_MCP_FE",
    "left_ring_MCP_AA",
    "left_ring_PIP",
    "left_ring_DIP",
    "left_pinky_CMC",
    "left_pinky_MCP_FE",
    "left_pinky_MCP_AA",
    "left_pinky_PIP",
    "left_pinky_DIP",
]
SHARPA_RIGHT_HAND_JOINT_ORDER = [
    "right_thumb_CMC_FE",
    "right_thumb_CMC_AA",
    "right_thumb_MCP_FE",
    "right_thumb_MCP_AA",
    "right_thumb_IP",
    "right_index_MCP_FE",
    "right_index_MCP_AA",
    "right_index_PIP",
    "right_index_DIP",
    "right_middle_MCP_FE",
    "right_middle_MCP_AA",
    "right_middle_PIP",
    "right_middle_DIP",
    "right_ring_MCP_FE",
    "right_ring_MCP_AA",
    "right_ring_PIP",
    "right_ring_DIP",
    "right_pinky_CMC",
    "right_pinky_MCP_FE",
    "right_pinky_MCP_AA",
    "right_pinky_PIP",
    "right_pinky_DIP",
]


def _bootstrap_trex_imports() -> None:
    if "coal" not in sys.modules:
        coal = types.ModuleType("coal")
        coal.Box = lambda *args, **kwargs: None
        sys.modules["coal"] = coal

    vega_1 = types.SimpleNamespace(
        urdf=VEGA_URDF,
        _parent_dir=VEGA_PKG,
        srdf=VEGA_SRDF,
    )
    vega_1_mod = types.ModuleType("dexmate_urdf.robots.humanoid.vega_1")
    vega_1_mod.vega_1 = vega_1
    humanoid = types.ModuleType("dexmate_urdf.robots.humanoid")
    humanoid.vega_1 = vega_1_mod
    robots = types.ModuleType("dexmate_urdf.robots")
    robots.humanoid = humanoid
    dexmate_urdf = types.ModuleType("dexmate_urdf")
    dexmate_urdf.robots = robots
    for name, mod in [
        ("dexmate_urdf", dexmate_urdf),
        ("dexmate_urdf.robots", robots),
        ("dexmate_urdf.robots.humanoid", humanoid),
        ("dexmate_urdf.robots.humanoid.vega_1", vega_1_mod),
    ]:
        sys.modules.setdefault(name, mod)

    qs = str(_QS_SRC)
    if qs not in sys.path:
        sys.path.insert(0, qs)


@lru_cache(maxsize=1)
def _load_robot_modules():
    _bootstrap_trex_imports()
    from trex_dataset_quickstart.robot import (  # noqa: WPS433
        build_full_robot,
        build_reduced_bimanual_robot,
        forward_kinematics,
    )

    return build_full_robot, build_reduced_bimanual_robot, forward_kinematics


@lru_cache(maxsize=1)
def get_full_robot() -> tuple[RobotWrapper, Callable, Callable]:
    build_full_robot, _, _ = _load_robot_modules()
    return build_full_robot({"head": DEFAULT_HEAD, "torso": DEFAULT_TORSO})


@lru_cache(maxsize=1)
def get_bimanual_robot() -> tuple[RobotWrapper, Callable, Callable]:
    _, build_reduced_bimanual_robot, _ = _load_robot_modules()
    return build_reduced_bimanual_robot({"head": DEFAULT_HEAD, "torso": DEFAULT_TORSO})


def state_to_components(state58: np.ndarray) -> dict[str, np.ndarray]:
    s = np.asarray(state58, dtype=np.float64).reshape(-1)
    if s.shape[0] != 58:
        raise ValueError(f"expected 58-dim state, got {s.shape[0]}")
    return {
        "left_arm": s[0:7],
        "left_hand": s[7:29],
        "right_arm": s[29:36],
        "right_hand": s[36:58],
    }


def hand_joint_positions_3d(
    robot: RobotWrapper,
    qpos: np.ndarray,
    joint_names: list[str],
) -> np.ndarray:
    pin.forwardKinematics(robot.model, robot.data, qpos)
    pin.updateFramePlacements(robot.model, robot.data)
    pts = np.zeros((len(joint_names), 3), dtype=np.float64)
    for i, name in enumerate(joint_names):
        fid = robot.model.getFrameId(name, pin.FrameType.JOINT)
        pts[i] = robot.data.oMf[fid].translation
    return pts


def frame_pose_matrix(robot: RobotWrapper, qpos: np.ndarray, frame_name: str) -> np.ndarray:
    pin.forwardKinematics(robot.model, robot.data, qpos)
    pin.updateFramePlacements(robot.model, robot.data)
    fid = robot.model.getFrameId(frame_name)
    se3 = robot.data.oMf[fid]
    T = np.eye(4, dtype=np.float64)
    T[:3, :3] = se3.rotation
    T[:3, 3] = se3.translation
    return T


def hand_keypoints_world(
    state58: np.ndarray,
) -> tuple[np.ndarray, np.ndarray, np.ndarray, np.ndarray]:
    """Return left/right hand (22,3) keypoints and L_ee/R_ee cam-to-world 4x4."""
    comps = state_to_components(state58)
    full_robot, assemble_full, _ = get_full_robot()
    bimanual_robot, assemble_bimanual, _ = get_bimanual_robot()

    q_full = assemble_full(comps)
    q_bi = assemble_bimanual(
        {"left_arm": comps["left_arm"], "right_arm": comps["right_arm"]},
    )

    left_pts = hand_joint_positions_3d(full_robot, q_full, SHARPA_LEFT_HAND_JOINT_ORDER)
    right_pts = hand_joint_positions_3d(full_robot, q_full, SHARPA_RIGHT_HAND_JOINT_ORDER)
    T_left_ee = frame_pose_matrix(full_robot, q_full, "L_ee")
    T_right_ee = frame_pose_matrix(full_robot, q_full, "R_ee")
    T_head_cam = frame_pose_matrix(bimanual_robot, q_bi, "zed_left_camera")
    return left_pts, right_pts, T_head_cam, (T_left_ee, T_right_ee)