import { normalizePublishedPageSlug } from 'soma-core';

const PHRASE_ALIASES: ReadonlyArray<readonly [RegExp, string]> = [
  [/我的工作台/u, 'myworkspace'],
  [/个人工作台/u, 'myworkspace'],
  [/供应链/u, 'supply-chain'],
  [/驾驶舱/u, 'dashboard'],
  [/仪表盘/u, 'dashboard'],
  [/工作台/u, 'workspace'],
  [/订单/u, 'orders'],
  [/客户/u, 'customers'],
  [/销售/u, 'sales'],
  [/运营/u, 'operations'],
  [/风险/u, 'risk'],
  [/项目/u, 'projects'],
  [/任务/u, 'tasks'],
];

const GENERIC_LATIN_WORDS = new Set([
  'a', 'an', 'the', 'page', 'build', 'create', 'generate', 'generated', 'new',
]);

function stableHash(value: string): string {
  let hash = 2166136261;
  for (const char of value) {
    hash ^= char.codePointAt(0) ?? 0;
    hash = Math.imul(hash, 16777619);
  }
  return (hash >>> 0).toString(36);
}

function explicitPath(source: string): string | null {
  const match = source.match(/(?:^|[\s：:，,（(])\/([a-zA-Z0-9][a-zA-Z0-9_-]{0,63})(?=$|[\s，,。.!！?？）)])/u);
  return normalizePublishedPageSlug(match?.[1]);
}

function semanticChineseSlug(source: string): string | null {
  const exact = PHRASE_ALIASES.find(([pattern]) => pattern.test(source));
  if (exact?.[1] === 'myworkspace') return exact[1];

  const matches = PHRASE_ALIASES
    .map(([pattern, value]) => ({ index: source.search(pattern), value }))
    .filter((item) => item.index >= 0)
    .sort((left, right) => left.index - right.index);
  const parts: string[] = [];
  for (const { value } of matches) {
    if (!parts.includes(value)) parts.push(value);
  }
  return normalizePublishedPageSlug(parts.join('-'));
}

function latinSlug(source: string): string | null {
  const words = source.toLowerCase().match(/[a-z0-9]+/g) ?? [];
  const meaningful = words.filter((word) => !GENERIC_LATIN_WORDS.has(word));
  return normalizePublishedPageSlug(meaningful.slice(0, 6).join('-'));
}

/**
 * 为页面蓝图补齐稳定公开身份。模型负责语义命名；显式路径、常用中文语义和
 * 稳定 hash 是防止旧模型/降级输出漏 slug 时退回同一个固定页面的三层兜底。
 */
export function resolvePageSlug(input: {
  candidate?: unknown;
  baseSlug?: unknown;
  title?: unknown;
  requirement?: unknown;
}): string {
  for (const candidate of [input.candidate, input.baseSlug]) {
    const normalized = normalizePublishedPageSlug(candidate);
    if (normalized) return normalized;
  }

  const source = [input.requirement, input.title]
    .filter((value): value is string => typeof value === 'string' && value.trim() !== '')
    .join(' ')
    .trim();
  return explicitPath(source)
    ?? semanticChineseSlug(source)
    ?? latinSlug(source)
    ?? `page-${stableHash(source || 'soma-page')}`;
}