import os
import time
from dataclasses import dataclass, field
from typing import Any, Dict, Literal, Optional

import cv2
import numpy as np

from ..inference.classical import detect_classical
from ..inference.dl import DL_MODELS, detect_dl


DEFAULT_PARAMS: Dict[str, Any] = {
    "canny_low": 50,
    "canny_high": 150,
    "harris_k": 0.05,
    "harris_block": 2,
    "harris_ksize": 3,
    "hough_thresh": 50,
    "hough_min_len": 30,
    "hough_max_gap": 5,
    "ellipse_min_area": 300,
    "max_ellipses": 5,
    "line_detector": "hough",
    "dexined_threshold_mode": "adaptive",
    "dexined_threshold_sigma": 1.0,
    "dexined_threshold_offset": 0.0,
    "dexined_threshold_value": 0.3,
    "dexined_use_marching_squares": False,
}

def _to_bool(value: Any) -> bool:
    if isinstance(value, bool):
        return value
    if isinstance(value, str):
        return value.strip().lower() in {"1", "true", "yes", "on"}
    return bool(value)


PARAM_TYPES: Dict[str, Any] = {
    "canny_low": int,
    "canny_high": int,
    "harris_k": float,
    "harris_block": int,
    "harris_ksize": int,
    "hough_thresh": int,
    "hough_min_len": int,
    "hough_max_gap": int,
    "ellipse_min_area": int,
    "max_ellipses": int,
    "line_detector": lambda x: str(x).lower(),
    "dexined_threshold_mode": lambda x: str(x).lower(),
    "dexined_threshold_sigma": float,
    "dexined_threshold_offset": float,
    "dexined_threshold_value": float,
    "dexined_use_marching_squares": _to_bool,
}

CLASSICAL_MODEL_INFO = {"name": "opencv-classical", "version": cv2.__version__}

try:
    import onnxruntime as ort  # type: ignore
except Exception:  # pragma: no cover
    ort = None  # type: ignore

DL_MODEL_INFO = {
    "name": "onnxruntime" if ort is not None else "onnxruntime-missing",
    "version": getattr(ort, "__version__", "unknown"),
}


def merge_params(params: Optional[Dict[str, Any]]) -> Dict[str, Any]:
    merged = DEFAULT_PARAMS.copy()
    if params:
        for key, value in params.items():
            if value is None or key not in DEFAULT_PARAMS:
                continue
            caster = PARAM_TYPES.get(key, lambda x: x)
            try:
                merged[key] = caster(value)
            except (TypeError, ValueError):
                continue
    return merged


@dataclass
class DetectionResult:
    overlays: Dict[str, np.ndarray] = field(default_factory=dict)
    features: Dict[str, Dict[str, Any]] = field(default_factory=dict)
    timings_ms: Dict[str, float] = field(default_factory=dict)
    fps_estimate: Optional[float] = None
    models: Dict[str, Dict[str, Any]] = field(default_factory=dict)


def run_detection(
    image: np.ndarray,
    detector: str,
    params: Optional[Dict[str, Any]] = None,
    mode: Literal["classical", "dl", "both"] = "classical",
    dl_choice: Optional[str] = None,
) -> DetectionResult:
    merged = merge_params(params)
    overlays: Dict[str, np.ndarray] = {}
    features: Dict[str, Dict[str, Any]] = {}
    timings: Dict[str, float] = {}
    models: Dict[str, Dict[str, Any]] = {}

    execute_classical = mode in ("classical", "both")
    execute_dl = mode in ("dl", "both")

    total_ms = 0.0

    if execute_classical:
        t0 = time.perf_counter()
        classical_img, classical_meta = detect_classical(
            image,
            detector,
            merged["canny_low"],
            merged["canny_high"],
            merged["harris_k"],
            merged["harris_block"],
            merged["harris_ksize"],
            merged["hough_thresh"],
            merged["hough_min_len"],
            merged["hough_max_gap"],
            merged["ellipse_min_area"],
            merged["max_ellipses"],
            merged["line_detector"],
        )
        t_ms = (time.perf_counter() - t0) * 1000.0
        overlays["classical"] = classical_img
        features["classical"] = classical_meta
        timings["classical"] = round(t_ms, 2)
        models["classical"] = CLASSICAL_MODEL_INFO
        total_ms += t_ms

    if execute_dl:
        t0 = time.perf_counter()
        dl_img, dl_meta = detect_dl(image, detector, dl_choice, params=merged)
        t_ms = (time.perf_counter() - t0) * 1000.0
        overlays["dl"] = dl_img
        features["dl"] = dl_meta
        timings["dl"] = round(t_ms, 2)
        model_name = (
            os.path.basename(dl_meta["model_path"]) if "model_path" in dl_meta else DL_MODEL_INFO["name"]
        )
        models["dl"] = {"name": model_name, "version": DL_MODEL_INFO["version"]}
        total_ms += t_ms

    timings["total"] = round(total_ms, 2)
    fps = round(1000.0 / total_ms, 2) if total_ms > 0 else None

    return DetectionResult(
        overlays=overlays,
        features=features,
        timings_ms=timings,
        fps_estimate=fps,
        models=models,
    )


__all__ = [
    "DetectionResult",
    "DEFAULT_PARAMS",
    "DL_MODELS",
    "merge_params",
    "run_detection",
]