// Leader round2 spec: 登录后默认页顶部指标卡 + 项目行迷你权益缩略图。
// 纯函数层，聚合合同在 dashboardMetrics.test.ts 做真实断言。
// 取不到的字段一律占位 "-"，不得编造数字。

export interface DashboardMetric {
  projectCount: number;
  datasetCount: number;
  runningRuns: number;
  doneRuns: number;
  /** "7 次" 或 "-"（后端无请求计数时） */
  usageLabel: string;
  /** 次要说明：token 计数摘要，无数据为空串 */
  usageTokens: string;
}

function kify(n: number): string {
  if (n >= 10000) return `${Math.round(n / 1000)}k`;
  if (n >= 1000) return `${(n / 1000).toFixed(1)}k`;
  return `${n}`;
}

export function aggregateDashboard(input: {
  projects?: { id: string }[] | null;
  datasets?: { id: string }[] | null;
  runs?: { id: string; status: string; result?: unknown }[] | null;
  usage?: { totals?: { input_tokens?: number; output_tokens?: number; requests?: number } } | null;
}): DashboardMetric {
  const projects = Array.isArray(input.projects) ? input.projects : [];
  const datasets = Array.isArray(input.datasets) ? input.datasets : [];
  const runs = Array.isArray(input.runs) ? input.runs : [];
  const runningRuns = runs.filter((r) => r.status === 'running' || r.status === 'queued').length;
  const doneRuns = runs.filter((r) => r.status === 'succeeded').length;

  const t = input.usage?.totals;
  let usageLabel = '-';
  let usageTokens = '';
  if (t && typeof t.requests === 'number') {
    usageLabel = `${t.requests} 次`;
    const inTok = t.input_tokens ?? 0;
    const outTok = t.output_tokens ?? 0;
    usageTokens = `(${kify(inTok)}/${kify(outTok)} tok)`;
  }

  return {
    projectCount: projects.length,
    datasetCount: datasets.length,
    runningRuns,
    doneRuns,
    usageLabel,
    usageTokens
  };
}

export interface SparkEndpoints {
  first: number;
  last: number;
}

/**
 * Per-project latest backtest endpoints for the project-row sparkline.
 * Latest = max created_at among runs whose result carries equity points.
 * A project without any chart-carrying run gets NO entry (caller must not
 * render a sparkline in that case).
 */
export function sparkFirstLast(
  runs: { project_id?: string; created_at?: string; result?: { equity?: { equity: number }[] } | null }[]
): Map<string, { first: number; last: number }> {
  const best = new Map<string, { at: string; first: number; last: number }>();
  const out = new Map<string, { first: number; last: number }>();
  for (const r of runs) {
    const eq = r.result?.equity;
    if (!r.project_id || !Array.isArray(eq) || eq.length < 2) continue;
    const prev = best.get(r.project_id);
    if (prev && prev.at >= (r.created_at ?? '')) continue;
    best.set(r.project_id, { at: r.created_at ?? '', first: eq[0].equity, last: eq[eq.length - 1].equity });
  }
  for (const [k, v] of best) out.set(k, { first: v.first, last: v.last });
  return out;
}