import os
import json
import logging
import torch
import cv2
import zipfile
import shutil
from ultralytics import YOLO
from urllib.parse import urlparse

def load_pipeline_node(node_config: dict, mpta_dir: str) -> dict:
    model_path = os.path.join(mpta_dir, node_config["modelFile"])
    if not os.path.exists(model_path):
        logging.error(f"Model file {model_path} not found.")
        raise FileNotFoundError(f"Model file {model_path} not found.")
    logging.info(f"Loading model {node_config['modelId']} from {model_path}")
    model = YOLO(model_path)
    if torch.cuda.is_available():
        model.to("cuda")

    # map triggerClasses names → indices for YOLO
    names = model.names  # idx -> class name
    trigger_names = node_config.get("triggerClasses", [])
    trigger_inds = [i for i, nm in names.items() if nm in trigger_names]

    return {
        "modelId": node_config["modelId"],
        "modelFile": node_config["modelFile"],
        "triggerClasses": trigger_names,
        "triggerClassIndices": trigger_inds,
        "crop": node_config.get("crop", False),
        "minConfidence": node_config.get("minConfidence", 0.0),
        "model": model,
        "branches": [
            load_pipeline_node(child, mpta_dir)
            for child in node_config.get("branches", [])
        ]
    }

def load_pipeline_from_zip(zip_source: str, target_dir: str) -> dict:
    os.makedirs(target_dir, exist_ok=True)
    zip_path = os.path.join(target_dir, "pipeline.mpta")
    parsed = urlparse(zip_source)
    if parsed.scheme in ("", "file"):
        local = parsed.path if parsed.scheme == "file" else zip_source
        if not os.path.exists(local):
            logging.error(f"Local file {local} does not exist.")
            return None
        shutil.copy(local, zip_path)
    else:
        logging.error("HTTP download not supported; use local file.")
        return None

    with zipfile.ZipFile(zip_path, "r") as z:
        z.extractall(target_dir)
    os.remove(zip_path)

    base = os.path.splitext(os.path.basename(zip_source))[0]
    mpta_dir = os.path.join(target_dir, base)
    cfg = os.path.join(mpta_dir, "pipeline.json")
    if not os.path.exists(cfg):
        logging.error("pipeline.json not found in archive.")
        return None

    with open(cfg) as f:
        pipeline_config = json.load(f)
    return load_pipeline_node(pipeline_config["pipeline"], mpta_dir)


def run_pipeline(frame, node: dict, return_bbox: bool=False):
    """
    - For detection nodes (task != 'classify'):
        • runs `track(..., classes=triggerClassIndices)`
        • picks top box ≥ minConfidence
        • optionally crops & resizes → recurse into child
        • else returns (det_dict, bbox)
    - For classify nodes:
        • runs `predict()`
        • returns top (class,confidence) and no bbox
    """
    try:
        task = getattr(node["model"], "task", None)

        # ─── Classification stage ───────────────────────────────────
        # if task == "classify":
        #     results = node["model"].predict(frame, stream=False)
        #     dets = []
        #     for r in results:
        #         probs = r.probs
        #         if probs is not None:
        #             # sort descending
        #             idxs = probs.argsort(descending=True)
        #             for cid in idxs:
        #                 dets.append({
        #                     "class": node["model"].names[int(cid)],
        #                     "confidence": float(probs[int(cid)]),
        #                     "id": None
        #                 })
        #     if not dets:
        #         return (None, None) if return_bbox else None

        #     best = dets[0]
        #     return (best, None) if return_bbox else best
        
        if task == "classify":
            # run the classifier and grab its top-1 directly via the Probs API
            results = node["model"].predict(frame, stream=False)
            # nothing returned?
            if not results:
                return (None, None) if return_bbox else None

            # take the first result's probs object
            r     = results[0]
            probs = r.probs
            if probs is None:
                return (None, None) if return_bbox else None

            # get the top-1 class index and its confidence
            top1_idx  = int(probs.top1)
            top1_conf = float(probs.top1conf)

            det = {
                "class": node["model"].names[top1_idx],
                "confidence": top1_conf,
                "id": None
            }
            return (det, None) if return_bbox else det


        # ─── Detection stage ────────────────────────────────────────
        # only look for your triggerClasses
        tk = node["triggerClassIndices"]
        res = node["model"].track(
            frame,
            stream=False,
            persist=True,
            **({"classes": tk} if tk else {})
        )[0]

        dets, boxes = [], []
        for box in res.boxes:
            conf = float(box.cpu().conf[0])
            cid  = int(box.cpu().cls[0])
            name = node["model"].names[cid]
            if conf < node["minConfidence"]:
                continue
            xy = box.cpu().xyxy[0]
            x1,y1,x2,y2 = map(int, xy)
            dets.append({"class": name, "confidence": conf,
                         "id": box.id.item() if hasattr(box, "id") else None})
            boxes.append((x1, y1, x2, y2))

        if not dets:
            return (None, None) if return_bbox else None

        # take highest‐confidence
        best_idx = max(range(len(dets)), key=lambda i: dets[i]["confidence"])
        best_det = dets[best_idx]
        best_box = boxes[best_idx]

        # ─── Branch (classification) ───────────────────────────────
        for br in node["branches"]:
            if (best_det["class"] in br["triggerClasses"]
                    and best_det["confidence"] >= br["minConfidence"]):
                # crop if requested
                sub = frame
                if br["crop"]:
                    x1,y1,x2,y2 = best_box
                    sub = frame[y1:y2, x1:x2]
                    sub = cv2.resize(sub, (224, 224))

                det2, _ = run_pipeline(sub, br, return_bbox=True)
                if det2:
                    # return classification result + original bbox
                    return (det2, best_box) if return_bbox else det2

        # ─── No branch matched → return this detection ─────────────
        return (best_det, best_box) if return_bbox else best_det

    except Exception as e:
        logging.error(f"Error in node {node.get('modelId')}: {e}")
        return (None, None) if return_bbox else None