import numpy as np
import pandas as pd
# def rank_results(
#     results,
#     metric="f1",
#     clf_average="mean",
#     weights=None
# ):
#     """
#     对 FSExecutor 输出结果进行排行榜排序

#     Parameters
#     ----------
#     results : list of dict
#         每个 dict 是一个算法在一个数据集上的结果
#     metric : str
#         使用的指标: 'f1' or 'auc'
#     clf_average : str
#         'mean' 或 'max'，表示跨分类器如何聚合
#     weights : dict or None
#         多指标加权，例如 {'f1':0.5, 'auc':0.5}

#     Returns
#     -------
#     ranked_df : pd.DataFrame
#     """

#     rows = []

#     for res in results:
#         algo = res["algorithm"]
#         metrics = res["metrics"]

#         # --------- 单指标 ----------
#         if weights is None:
#             vals = []
#             for clf, m in metrics.items():
#                 if metric in m:
#                     vals.append(m[metric])

#             if not vals:
#                 raise ValueError(f"No metric {metric} for {algo}")

#             score = np.mean(vals) if clf_average == "mean" else np.max(vals)

#         # --------- 多指标加权 ----------
#         else:
#             score = 0.0
#             for m_name, w in weights.items():
#                 vals = [
#                     metrics[clf][m_name]
#                     for clf in metrics
#                     if m_name in metrics[clf]
#                 ]
#                 score += w * np.mean(vals)

#         rows.append({
#             "algorithm": algo,
#             "score": score,
#             "num_features": res["num_features"],
#             "time": res.get("time", None)
#         })

#     df = pd.DataFrame(rows)

#     # --------- 按 score 排序 ----------
#     df = df.sort_values(
#         by="score",
#         ascending=False
#     ).reset_index(drop=True)

#     df["rank"] = df.index + 1

#     return df

def aggregate_metrics(metrics, w_f1=0.7, w_auc=0.3):
    """
    metrics:
        {
            "nb":  {"f1": x, "auc": y},
            "svm": {"f1": x, "auc": y},
            "rf":  {"f1": x, "auc": y},
        }
    """
    f1s = [m["f1"] for m in metrics.values()]
    aucs = [m["auc"] for m in metrics.values()]

    mean_f1 = sum(f1s) / len(f1s)
    mean_auc = sum(aucs) / len(aucs)

    return w_f1 * mean_f1 + w_auc * mean_auc,mean_f1,mean_auc

def rank_results(
    results,
):
    """
    results: list[dict]
    return: 排序后的 list[dict]（每个 dict 会新增 score 字段）
    """

    ranked = []

    for r in results:
        # 1. 性能融合
        perf_score,mean_f1,mean_auc = aggregate_metrics(r["metrics"])

        # 2. 惩罚项
        # feature_penalty = alpha * r["num_features"]
        # time_penalty = beta * r["time"]

        # final_score = perf_score - feature_penalty - time_penalty
        final_score = perf_score
        ranked.append({
            **r,
            "mean_f1":mean_f1,
            "mean_auc":mean_auc,
            "score": final_score,
            "perf_score": perf_score
        })

    # 3. 排序（score 越大越好）
    ranked.sort(key=lambda x: x["score"], reverse=True)

    return ranked