"""End-to-end orchestration and JSON reporting for RTK--IMU calibration."""

from __future__ import annotations

import csv
import json
from dataclasses import asdict, dataclass
from pathlib import Path
from typing import Any

import numpy as np

from imu_lidar.imu_io import load_imu_samples
from .rtk_imu_rotation import RotationCalibrationResult, RotationSession, solve_rtk_imu_rotation
from .rtk_imu_translation import TranslationCalibrationResult, solve_rtk_imu_translation
from .rtk_io import load_rtk_csv


DEFAULT_RTK_FRAME_DEFINITION = (
    "right-handed vehicle-fixed frame: +X ANT1(main,left)->ANT2(secondary,right), "
    "+Y vehicle forward/IMU +Y, +Z vehicle up/IMU +Z"
)
DEFAULT_RTK_REFERENCE_POINT = (
    "GGA ANT1/main-antenna phase center, 1.916499878 m above ground"
)


@dataclass(frozen=True)
class InventoryEntry:
    session_id: str
    batch_id: str
    imu_csv: Path
    rtk_csv: Path


def load_inventory(path: Path | str) -> list[InventoryEntry]:
    """Load the project RTK inventory and derive each paired IMU path."""

    source = Path(path)
    entries: list[InventoryEntry] = []
    with source.open("r", encoding="utf-8-sig", newline="") as handle:
        for row in csv.DictReader(handle):
            rtk_csv = Path(row["current_rtk_csv"])
            imu_csv = rtk_csv.with_name("imu.csv")
            entries.append(
                InventoryEntry(
                    session_id=row["session"],
                    batch_id=row["batch"],
                    imu_csv=imu_csv,
                    rtk_csv=rtk_csv,
                )
            )
    if not entries:
        raise ValueError(f"empty RTK inventory: {source}")
    return entries


def load_sessions(entries: list[InventoryEntry] | tuple[InventoryEntry, ...]) -> list[RotationSession]:
    sessions = []
    for entry in entries:
        sessions.append(
            RotationSession(
                session_id=entry.session_id,
                batch_id=entry.batch_id,
                imu=load_imu_samples(entry.imu_csv),
                rtk=load_rtk_csv(entry.rtk_csv),
            )
        )
    return sessions


def _jsonable(value: Any) -> Any:
    if isinstance(value, np.ndarray):
        return value.tolist()
    if isinstance(value, np.generic):
        return value.item()
    if isinstance(value, Path):
        return str(value)
    if hasattr(value, "__dataclass_fields__"):
        return {key: _jsonable(item) for key, item in asdict(value).items()}
    if isinstance(value, dict):
        return {str(key): _jsonable(item) for key, item in value.items()}
    if isinstance(value, (list, tuple)):
        return [_jsonable(item) for item in value]
    return value


def dataset_audit(sessions: list[RotationSession]) -> dict[str, Any]:
    rows = []
    for session in sessions:
        rtk = session.rtk
        valid_position = rtk.position_valid
        valid_attitude = rtk.attitude_valid & valid_position
        float_attitude = rtk.attitude_float & valid_position
        rows.append(
            {
                "session_id": session.session_id,
                "batch_id": session.batch_id,
                "imu_samples": int(session.imu.t_s.size),
                "rtk_samples": int(rtk.t_s.size),
                "fixed_position_ratio": float(np.mean(valid_position)),
                "fixed_attitude_ratio": float(np.mean(valid_attitude)),
                "float_attitude_ratio": float(np.mean(float_attitude)),
                "checksum_valid_ratio": float(np.mean(rtk.checksum_valid)),
                "common_time_span_s": [
                    float(max(session.imu.t_s[0], rtk.t_s[0])),
                    float(min(session.imu.t_s[-1], rtk.t_s[-1])),
                ],
                "origin_geodetic": list(rtk.origin_geodetic),
                "imu_source": str(session.imu.t_s.size) + " normalized samples",
                "rtk_source": str(rtk.source),
            }
        )
    return {"session_count": len(sessions), "sessions": rows}


def run_calibration(
    sessions: list[RotationSession],
    output_directory: Path | str,
    *,
    rotation_only: bool = False,
    compute_loo: bool = True,
    knot_step_s: float = 2.0,
    rtk_frame_definition: str = DEFAULT_RTK_FRAME_DEFINITION,
    rtk_reference_point: str = DEFAULT_RTK_REFERENCE_POINT,
) -> tuple[RotationCalibrationResult, TranslationCalibrationResult | None]:
    """Run calibration and publish human-readable JSON artifacts."""

    output = Path(output_directory)
    output.mkdir(parents=True, exist_ok=True)
    rotation = solve_rtk_imu_rotation(sessions, compute_loo=compute_loo)
    translation = None
    if not rotation_only and rotation.ok:
        translation = solve_rtk_imu_translation(
            sessions,
            rotation,
            knot_step_s=knot_step_s,
            compute_loo=compute_loo,
        )
    audit_payload = dataset_audit(sessions)
    rotation_payload = _jsonable(rotation)
    translation_payload = None if translation is None else _jsonable(translation)
    (output / "dataset_audit.json").write_text(
        json.dumps(audit_payload, ensure_ascii=False, indent=2) + "\n", encoding="utf-8"
    )
    (output / "rotation_result.json").write_text(
        json.dumps(rotation_payload, ensure_ascii=False, indent=2) + "\n", encoding="utf-8"
    )
    if translation_payload is not None:
        (output / "translation_result.json").write_text(
            json.dumps(translation_payload, ensure_ascii=False, indent=2) + "\n", encoding="utf-8"
        )
    interpretation_complete = bool(rtk_frame_definition.strip() and rtk_reference_point.strip())
    accepted = bool(
        rotation.ok and translation is not None and translation.ok and interpretation_complete
    )
    blockers = []
    if not rotation.ok:
        blockers.append('full RTK-to-IMU rotation is not observable from the lateral dual-antenna baseline')
    if translation is None or not translation.ok:
        blockers.append('translation is frozen until a full rotation is observable and accepted')
    if not rtk_frame_definition.strip():
        blockers.append('RTK frame_definition is empty')
    if not rtk_reference_point.strip():
        blockers.append('RTK reference_point is empty')
    summary = {
        "status": "accepted" if accepted else "diagnostic_not_accepted",
        "transform_convention": "T_RTK_IMU maps IMU coordinates into the RTK sensor frame",
        "rtk_frame_definition": rtk_frame_definition,
        "rtk_reference_point": rtk_reference_point,
        "interpretation_blockers": blockers,
        "R_RTK_IMU": rotation.R_RTK_IMU.tolist(),
        "t_RTK_IMU_m": None if translation is None else translation.t_RTK_IMU_m.tolist(),
        "T_RTK_IMU": None if translation is None else translation.T_RTK_IMU.tolist(),
        "rotation_ok": rotation.ok,
        "translation_ok": None if translation is None else translation.ok,
        "rotation_result": "rotation_result.json",
        "translation_result": None if translation is None else "translation_result.json",
        "dataset_audit": "dataset_audit.json",
    }
    (output / "summary.json").write_text(
        json.dumps(summary, ensure_ascii=False, indent=2) + "\n", encoding="utf-8"
    )
    return rotation, translation