#!/usr/bin/env python3
"""Single-ego LangCoop adapter for the CoDrive closed-loop benchmark."""

from __future__ import annotations

import json
import math
import os
import sys
import textwrap
import time
import xml.etree.ElementTree as ET
from collections import deque
from pathlib import Path

import carla
import cv2
import numpy as np
import yaml
from leaderboard.autoagents import autonomous_agent
from srunner.scenariomanager.carla_data_provider import CarlaDataProvider


LANGCOOP_ROOT = Path(
    os.environ.get(
        "LANGCOOP_ROOT",
        "/path/to/LangCoop",
    )
).resolve()
if str(LANGCOOP_ROOT) not in sys.path:
    sys.path.insert(0, str(LANGCOOP_ROOT))

from vlmdrive.controller.vlm_controller_speed_curvature import (  # noqa: E402
    VLMControllerSpeedCurvature,
)
from vlmdrive.vlm.vlm_planner_speed_curvature import (  # noqa: E402
    VLMPlannerSpeedCurvature,
)


def get_entry_point():
    return "CoDriveLangCoopAgent"


def _float_attr(element, name, default=0.0):
    return float(element.attrib.get(name, default))


class CoDriveLangCoopAgent(autonomous_agent.AutonomousAgent):
    """Run the official LangCoop speed-curvature planner as one CARLA agent.

    LangCoop's released evaluator controls multiple ego vehicles and returns a
    list of controls. CoDrive uses one ego vehicle, so this adapter preserves
    the released planner prompts, parser, and controller while translating the
    route navigation target and the temporally bounded cooperative warning.
    """

    def setup(self, path_to_conf_file, route_index=None):
        del path_to_conf_file, route_index
        self.track = autonomous_agent.Track.SENSORS
        self.step = -1
        self.current_route_hint = None
        self._message_disabled = os.environ.get(
            "LANGCOOP_DISABLE_MESSAGES",
            os.environ.get("SIMLINGO_DISABLE_ROUTE_LEVEL_HINTS", "0"),
        ).strip().lower() in {"1", "true", "yes", "on"}
        self._planning_interval_s = max(
            0.25, float(os.environ.get("LANGCOOP_PLANNING_INTERVAL_SECONDS", "2.0"))
        )
        self._api_base_url = os.environ.get(
            "LANGCOOP_API_BASE_URL", "http://127.0.0.1:8032/v1"
        )
        self._model_name = os.environ.get(
            "LANGCOOP_MODEL_NAME", "Qwen/Qwen2.5-VL-3B-Instruct-AWQ"
        )
        self._run_dir = Path(os.environ["RUN_DIR"]).resolve()
        self._save_root = Path(os.environ["SAVE_PATH"]).resolve() / "codrive_langcoop"
        self._frame_dir = self._save_root / "rgb_front"
        self._frame_dir.mkdir(parents=True, exist_ok=True)
        self._log_path = self._run_dir / "langcoop_io.jsonl"
        self._log_path.unlink(missing_ok=True)

        agent_config = (
            LANGCOOP_ROOT
            / "vlmdrive/agent/hypes_yaml/"
            "speed_curvature_CoT_concise_image_intent_2agent_qwen.yaml"
        )
        control_config = (
            LANGCOOP_ROOT / "vlmdrive/controller/hypes_yaml/speed_curvature.yaml"
        )
        self._config = yaml.safe_load(agent_config.read_text(encoding="utf-8"))
        control_payload = yaml.safe_load(control_config.read_text(encoding="utf-8"))
        self._planner = VLMPlannerSpeedCurvature(
            name="api",
            api_model_name=self._model_name,
            api_base_url=self._api_base_url,
            api_key="dummy_key",
        )
        self._controller = VLMControllerSpeedCurvature(
            control_payload["model"]["config"]
        )
        self._history = deque(maxlen=5)
        self._prediction = None
        self._prediction_time = None
        self._previous_position = None
        self._previous_yaw = None
        self._route_cursor = 0
        self._route_points = []
        self._scenario = self._load_scenario_spec(Path(os.environ["ROUTES"]))
        self._last_control = carla.VehicleControl()
        print(
            "[CoDriveLangCoop] "
            f"model={self._model_name} api={self._api_base_url} "
            f"messages={'off' if self._message_disabled else 'on'} "
            f"planning_interval={self._planning_interval_s:.2f}s",
            flush=True,
        )

    @staticmethod
    def _load_scenario_spec(route_path):
        root = ET.parse(route_path).getroot()
        scenario = root.find(".//scenario")
        if scenario is None:
            return {
                "name": "",
                "type": "",
                "prompt": "",
                "collision_point": None,
            }
        prompt_node = scenario.find("cooperative_prompt")
        if prompt_node is None:
            prompt_node = scenario.find("./parameters/parameter[@name='cooperative_prompt']")
        collision = scenario.find("collision_point")
        point = None
        if collision is not None:
            point = carla.Location(
                x=_float_attr(collision, "x"),
                y=_float_attr(collision, "y"),
                z=_float_attr(collision, "z"),
            )
        return {
            "name": scenario.attrib.get("name", scenario.attrib.get("type", "")),
            "type": scenario.attrib.get("type", ""),
            "prompt": (
                prompt_node.attrib.get("value", "")
                if prompt_node is not None
                else ""
            ).strip(),
            "collision_point": point,
        }

    def sensors(self):
        return [
            {
                "type": "sensor.camera.rgb",
                "x": 1.3,
                "y": 0.0,
                "z": 2.3,
                "roll": 0.0,
                "pitch": 0.0,
                "yaw": 0.0,
                "width": 800,
                "height": 600,
                "fov": 100,
                "id": "rgb_front",
            },
            {
                "type": "sensor.other.imu",
                "x": 0.0,
                "y": 0.0,
                "z": 0.0,
                "roll": 0.0,
                "pitch": 0.0,
                "yaw": 0.0,
                "id": "imu",
            },
            {
                "type": "sensor.other.gnss",
                "x": 0.0,
                "y": 0.0,
                "z": 0.0,
                "roll": 0.0,
                "pitch": 0.0,
                "yaw": 0.0,
                "id": "gps",
            },
            {
                "type": "sensor.speedometer",
                "reading_frequency": 20,
                "id": "speed",
            },
        ]

    def _ensure_route_points(self):
        if self._route_points:
            return
        # Leaderboard stores the original dense route before constructing the
        # 50 m navigation-command plan. LangCoop needs the dense geometry for
        # local steering; using the command plan can place the next target
        # across an intersection and cause an immediate off-route turn.
        route = (
            getattr(self, "org_dense_route_world_coord", None)
            or self._global_plan_world_coord
            or []
        )
        for transform, _command in route:
            location = transform.location if hasattr(transform, "location") else transform
            self._route_points.append(
                np.array([float(location.x), float(location.y)], dtype=np.float64)
            )

    def _navigation_target(self, ego_transform):
        self._ensure_route_points()
        if not self._route_points:
            return np.array([0.0, -20.0], dtype=np.float64)
        position = np.array(
            [ego_transform.location.x, ego_transform.location.y], dtype=np.float64
        )
        start = max(0, self._route_cursor - 5)
        stop = min(len(self._route_points), self._route_cursor + 80)
        nearest = min(
            range(start, stop),
            key=lambda index: float(np.linalg.norm(self._route_points[index] - position)),
        )
        self._route_cursor = max(self._route_cursor, nearest)
        target_index = nearest
        distance = 0.0
        while target_index + 1 < len(self._route_points) and distance < 18.0:
            distance += float(
                np.linalg.norm(
                    self._route_points[target_index + 1]
                    - self._route_points[target_index]
                )
            )
            target_index += 1
        delta = self._route_points[target_index] - position
        yaw = math.radians(float(ego_transform.rotation.yaw))
        forward = np.array([math.cos(yaw), math.sin(yaw)])
        right = np.array([-math.sin(yaw), math.cos(yaw)])
        forward_m = float(delta @ forward)
        right_m = float(delta @ right)
        # LangCoop describes [lateral, -forward] as right/left and front/back.
        return np.array([right_m, -forward_m], dtype=np.float64)

    def _event_state(self):
        if not self._scenario["name"]:
            return {}
        try:
            from srunner.scenarios.closed_coopeval_scenarios import (
                get_ablation_event_state,
            )

            return get_ablation_event_state(self._scenario["name"]) or {}
        except Exception:
            return {}

    @staticmethod
    def _relative_description(ego_transform, point):
        if point is None:
            return "at the reported conflict point ahead"
        delta = np.array(
            [
                point.x - ego_transform.location.x,
                point.y - ego_transform.location.y,
            ]
        )
        yaw = math.radians(float(ego_transform.rotation.yaw))
        forward = float(delta @ np.array([math.cos(yaw), math.sin(yaw)]))
        right = float(delta @ np.array([-math.sin(yaw), math.cos(yaw)]))
        lateral = "right" if right >= 0.0 else "left"
        longitudinal = "ahead" if forward >= 0.0 else "behind"
        return (
            f"{abs(forward):.1f} meters {longitudinal} and "
            f"{abs(right):.1f} meters to the {lateral}"
        )

    def _cooperative_message(self, ego_transform):
        state = self._event_state()
        active = (
            not self._message_disabled
            and bool(state.get("hint_reached", False))
            and not bool(state.get("hazard_cleared", False))
            and bool(self._scenario["prompt"])
        )
        if not active:
            self.current_route_hint = None
            return ""
        position = self._relative_description(
            ego_transform, self._scenario["collision_point"]
        )
        canonical = self._scenario["prompt"]
        rendered = canonical.replace("<FRONT_CAR_POS>", position)
        self.current_route_hint = {
            "name": self._scenario["name"],
            "text": canonical,
            "rendered_text": rendered,
            "position_description": position,
        }
        return (
            "A cooperative road user reports the following safety warning: "
            f"{rendered}"
        )

    @staticmethod
    def _speed(input_data):
        value = input_data["speed"][1]
        if isinstance(value, dict):
            if "speed" in value:
                return float(value["speed"])
            if "move_state" in value:
                return float(value["move_state"].get("speed", 0.0))
        return float(value)

    def _history_record(self, timestamp, speed, ego_transform):
        position = np.array(
            [ego_transform.location.x, ego_transform.location.y], dtype=np.float64
        )
        yaw = math.radians(float(ego_transform.rotation.yaw))
        if self._previous_position is None:
            curvature = 0.0
        else:
            distance = max(1e-6, float(np.linalg.norm(position - self._previous_position)))
            yaw_delta = math.atan2(
                math.sin(yaw - self._previous_yaw),
                math.cos(yaw - self._previous_yaw),
            )
            curvature = math.degrees(yaw_delta) / distance
        self._previous_position = position
        self._previous_yaw = yaw
        self._history.append(
            {
                "timestamp": round(float(timestamp), 3),
                "speed": round(float(speed), 3),
                "curvature": round(float(curvature), 3),
                "waypoints": [0.0, 0.0],
            }
        )

    def _plan(self, image_rgb, timestamp, speed, target, cooperative_message):
        prompts = self._config["planning"]["prompt_usage"]
        templates = self._config["planning"]["prompt_template"]
        scene, scene_prompt = self._planner.get_scene_description(
            image_rgb, prompts, templates
        )
        objects, object_prompt = self._planner.get_objects_description(
            image_rgb, prompts, templates
        )
        target_description = self._planner.get_target_description(target, templates)
        intention, intention_prompt = self._planner.get_intent_description(
            image_rgb, prompts, target_description, templates
        )
        history = json.dumps({"ego_history": list(self._history)}, indent=2)
        prediction = self._planner._gen_individual_info(
            image_rgb,
            history,
            self._config,
            scene,
            objects,
            intention,
            target_description,
            cooperative_message,
            idx=0,
        )
        if prediction is None:
            raise RuntimeError("LangCoop returned no parseable planning output")
        self._prediction = prediction
        self._prediction_time = float(timestamp)
        record = {
            "frame": self.step,
            "timestamp": float(timestamp),
            "speed_mps": float(speed),
            "target_lateral_forward_m": [float(target[0]), float(-target[1])],
            "cooperative_message": cooperative_message or None,
            "canonical_hint": (
                self.current_route_hint["text"] if self.current_route_hint else None
            ),
            "prompts": {
                "scene": scene_prompt,
                "objects": object_prompt,
                "intent": intention_prompt,
            },
            "intermediate": {
                "scene": scene,
                "objects": objects,
                "intent": intention,
                "target": target_description,
            },
            "prediction": {
                "target_speed_mps": [
                    float(value) for value in prediction["target_speed"]
                ],
                "curvature_degree_per_m": [
                    float(value) for value in prediction["curvature"]
                ],
                "dt_seconds": float(prediction["dt"]),
            },
        }
        with self._log_path.open("a", encoding="utf-8") as stream:
            stream.write(json.dumps(record, ensure_ascii=False) + "\n")

    def _fallback_control(self, speed, target):
        forward = max(1.0, float(-target[1]))
        angle = math.atan2(float(target[0]), forward)
        control = carla.VehicleControl()
        control.steer = float(np.clip(angle / 0.8, -1.0, 1.0))
        control.throttle = 0.45 if speed < 5.0 else 0.15
        control.brake = 0.0
        return control

    def _prediction_control(self, timestamp, speed, target):
        if self._prediction is None or self._prediction_time is None:
            return self._fallback_control(speed, target)
        dt = max(0.1, float(self._prediction["dt"]))
        count = len(self._prediction["target_speed"])
        index = min(count - 1, max(0, int((float(timestamp) - self._prediction_time) / dt)))
        route_info = {
            "speed": float(speed),
            "target": target,
            **self._prediction,
        }
        steer, throttle, brake, _meta = self._controller.run_step(
            route_info, buffer_idx=index
        )
        return carla.VehicleControl(
            steer=float(steer),
            throttle=float(throttle),
            brake=float(bool(brake)),
            hand_brake=False,
        )

    def _save_frame(self, image_bgr, speed, control, message):
        canvas = image_bgr.copy()
        lines = [
            f"LangCoop | speed={speed:.2f} m/s | "
            f"throttle={control.throttle:.2f} brake={control.brake:.0f}",
            "Cooperative message: " + (message if message else "None"),
        ]
        y = 28
        for line in lines:
            for wrapped in textwrap.wrap(line, width=95) or [""]:
                cv2.putText(
                    canvas,
                    wrapped,
                    (12, y),
                    cv2.FONT_HERSHEY_SIMPLEX,
                    0.52,
                    (0, 0, 0),
                    3,
                    cv2.LINE_AA,
                )
                cv2.putText(
                    canvas,
                    wrapped,
                    (12, y),
                    cv2.FONT_HERSHEY_SIMPLEX,
                    0.52,
                    (255, 255, 255),
                    1,
                    cv2.LINE_AA,
                )
                y += 22
        cv2.imwrite(str(self._frame_dir / f"{self.step:06d}.jpg"), canvas)

    def run_step(self, input_data, timestamp):
        self.step += 1
        raw = input_data["rgb_front"][1]
        image_bgr = raw[:, :, :3]
        image_rgb = cv2.cvtColor(image_bgr, cv2.COLOR_BGR2RGB)
        speed = self._speed(input_data)
        ego = CarlaDataProvider.get_hero_actor()
        if ego is None:
            return carla.VehicleControl(brake=1.0)
        ego_transform = ego.get_transform()
        target = self._navigation_target(ego_transform)
        message = self._cooperative_message(ego_transform)
        self._history_record(timestamp, speed, ego_transform)

        should_plan = (
            self._prediction is None
            or self._prediction_time is None
            or float(timestamp) - self._prediction_time >= self._planning_interval_s
        )
        if should_plan:
            started = time.monotonic()
            try:
                self._plan(image_rgb, timestamp, speed, target, message)
                print(
                    f"[CoDriveLangCoop] planned frame={self.step} "
                    f"wall_time={time.monotonic() - started:.2f}s "
                    f"hint={bool(message)}",
                    flush=True,
                )
            except Exception as error:
                print(f"[CoDriveLangCoop] planning failed: {error}", flush=True)

        control = self._prediction_control(timestamp, speed, target)
        self._last_control = control
        self._save_frame(
            image_bgr,
            speed,
            control,
            self.current_route_hint["rendered_text"]
            if self.current_route_hint
            else "",
        )
        return control

    def destroy(self):
        self._planner = None
        self._controller = None