// metric_presenter.js — 统一维护指标语义（高分好 / 低分好）、颜色阈值与简要说明。

(function attachMetricPresenter(globalObj) {
  const METRIC_META = {
    faithfulness: {
      direction: "higher_better",
      description: "回答是否被检索内容直接支持，越高越可靠。",
    },
    answer_relevancy: {
      direction: "higher_better",
      description: "回答与问题是否紧密相关，越高越切题。",
    },
    context_recall: {
      direction: "higher_better",
      description: "检索片段覆盖标准答案关键信息的程度，越高越完整。",
    },
    context_precision: {
      direction: "higher_better",
      description: "检索片段中有效信息的占比，越高越精准。",
    },
    noise_sensitivity: {
      direction: "lower_better",
      description: "对噪声上下文的敏感程度，越低说明抗干扰能力越强。",
    },
    factual_correctness: {
      direction: "higher_better",
      description: "回答与标准答案在事实层面的吻合程度，越高越准确。",
    },
    semantic_similarity: {
      direction: "higher_better",
      description: "回答与标准答案在语义上的相似程度，越高越接近。",
    },
  };

  function isLowerBetter(metricName) {
    return METRIC_META[metricName]?.direction === "lower_better";
  }

  function scoreClass(metricName, value) {
    if (value === null || value === undefined || Number.isNaN(Number(value))) return "na";
    const numeric = Number(value);
    if (isLowerBetter(metricName)) {
      if (numeric <= 0.15) return "good";
      if (numeric <= 0.35) return "warn";
      return "bad";
    }
    if (numeric >= 0.85) return "good";
    if (numeric >= 0.65) return "warn";
    return "bad";
  }

  function describeMetric(metricName) {
    return METRIC_META[metricName]?.description || "该指标用于衡量当前问答样本的评估表现。";
  }

  function binColor(metricName, lower) {
    const numeric = Number(lower);
    if (isLowerBetter(metricName)) {
      if (numeric < 0.2) return "#16a34a";
      if (numeric < 0.4) return "#84cc16";
      if (numeric < 0.6) return "#eab308";
      if (numeric < 0.8) return "#f97316";
      return "#dc2626";
    }
    if (numeric >= 0.8) return "#16a34a";
    if (numeric >= 0.6) return "#84cc16";
    if (numeric >= 0.4) return "#eab308";
    if (numeric >= 0.2) return "#f97316";
    return "#dc2626";
  }

  // 计算某指标本次相对上一次的涨跌信息，方向语义随指标而定
  // （noise_sensitivity 越低越好：下降=改善）。
  function deltaInfo(metricName, current, previous) {
    const isNum = (v) => v !== null && v !== undefined && !Number.isNaN(Number(v));
    if (!isNum(current) || !isNum(previous)) {
      return { hasData: false, delta: null, improved: null, arrow: "", magnitude: "", cls: "delta-flat" };
    }
    const delta = Number(current) - Number(previous);
    const rounded = Math.round(delta * 10000) / 10000;
    const arrow = rounded > 0 ? "▲" : rounded < 0 ? "▼" : "→";
    const magnitude = Math.abs(rounded).toFixed(2);
    const improved = isLowerBetter(metricName) ? rounded < 0 : rounded > 0;
    const cls = rounded === 0 ? "delta-flat" : improved ? "delta-good" : "delta-bad";
    return { hasData: true, delta: rounded, improved, arrow, magnitude, cls };
  }

  // 返回指标的"达标阈值"（柱状图对比用，方向感知）。
  // higher-better 指标：0.85；lower-better (noise_sensitivity)：0.15。
  function passThreshold(metricName) {
    return isLowerBetter(metricName) ? 0.15 : 0.85;
  }

  // 判断某指标的值是否达标。
  function meetsTarget(metricName, value) {
    if (value === null || value === undefined || Number.isNaN(Number(value))) return false;
    const v = Number(value);
    return isLowerBetter(metricName) ? v <= passThreshold(metricName) : v >= passThreshold(metricName);
  }

  globalObj.MetricPresenter = {
    scoreClass,
    describeMetric,
    binColor,
    isLowerBetter,
    deltaInfo,
    passThreshold,
    meetsTarget,
  };
})(window);