import type { CatalogMetrics } from "./types.js";

export interface CatalogMetricCounts {
  tables: number;
  columns: number;
  sensitiveColumns: number;
  relationships: number;
  describedTables: number;
  describedColumns: number;
}

export function hasCatalogDescription(target: {
  description: string | null;
  generatedDescription: string | null;
}): boolean {
  return Boolean(target.description?.trim() || target.generatedDescription?.trim());
}

export function latestCatalogTimestamp(
  values: readonly (string | null | undefined)[],
): string | null {
  let latest: number | undefined;
  for (const value of values) {
    if (!value) continue;
    const timestamp = Date.parse(value);
    if (!Number.isFinite(timestamp)) continue;
    latest = latest === undefined ? timestamp : Math.max(latest, timestamp);
  }
  return latest === undefined ? null : new Date(latest).toISOString();
}

export function createCatalogMetrics(
  databaseId: string | undefined,
  counts: CatalogMetricCounts,
  updatedAt: string | null,
): CatalogMetrics {
  const descriptionTargets = counts.tables + counts.columns;
  const describedTargets = counts.describedTables + counts.describedColumns;
  return {
    scope: databaseId === undefined ? "global" : "database",
    databaseId: databaseId ?? null,
    tables: counts.tables,
    columns: counts.columns,
    sensitiveColumns: counts.sensitiveColumns,
    relationships: counts.relationships,
    descriptionTargets,
    describedTargets,
    descriptionCoverage: descriptionTargets === 0
      ? 0
      : Math.round((describedTargets / descriptionTargets) * 100),
    updatedAt,
  };
}