import { searchSearxng } from './mindsearch-providers.mjs';

const LIVE_SEARCH_SKILLS = new Set(['web', 'search-enhanced', 'web-search']);

function envFlag(value, fallback = false) {
  const raw = String(value ?? '').trim().toLowerCase();
  if (!raw) return fallback;
  return ['1', 'true', 'yes', 'on'].includes(raw);
}

export function resolvePortalSearxngEndpoint(env = process.env, config = null) {
  const raw = String(
    env.TKMIND_SEARCH_SEARXNG_URL
      ?? config?.settings?.searxngEndpoint
      ?? '',
  ).trim();
  if (!raw) return '';
  try {
    const url = new URL(raw);
    if (url.hostname === 'host.docker.internal') url.hostname = '127.0.0.1';
    return url.toString();
  } catch {
    return '';
  }
}

export function shouldPrefetchLiveSearch({
  selectedSkill = '',
  suggestedSkill = '',
  env = process.env,
} = {}) {
  if (!envFlag(env.MEMIND_LIVE_SEARCH_PREFETCH, true)) return false;
  const skill = String(selectedSkill || suggestedSkill || '').trim();
  return LIVE_SEARCH_SKILLS.has(skill);
}

export function formatPrefetchedSearchContext(results = [], { query = '' } = {}) {
  const rows = (Array.isArray(results) ? results : [])
    .filter((item) => item?.title || item?.url)
    .slice(0, 10);
  if (!rows.length) return '';
  const lines = [
    '【联网搜索预取】系统已先调用专用联网搜索。请优先使用下列结果回答；不要向用户提及 SearXNG/DuckDuckGo 等中间件名称。',
    `查询：${String(query ?? '').trim()}`,
    '禁止先 fetch_url 抓取热榜/热搜整页。若需补充，先调用 tkmind_search，再按需读取个别可靠来源。',
    '',
  ];
  for (const item of rows) {
    lines.push(`${item.rank ?? ''}. ${item.title || item.url}`);
    if (item.url) lines.push(`   URL: ${item.url}`);
    if (item.snippet) lines.push(`   ${item.snippet}`);
  }
  return lines.join('\n').trim();
}

export function appendAgentVisibleText(userMessage, extraText) {
  const block = String(extraText ?? '').trim();
  if (!block) return userMessage;
  const content = Array.isArray(userMessage?.content) ? [...userMessage.content] : [];
  const extra = `\n\n${block}`;
  if (!content.length) {
    return {
      ...userMessage,
      content: [{ type: 'text', text: block }],
      metadata: {
        ...(userMessage?.metadata ?? {}),
        agentVisible: true,
      },
    };
  }
  const first = content[0];
  if (typeof first === 'string') {
    content[0] = `${first}${extra}`;
  } else if (first?.type === 'text') {
    content[0] = { ...first, text: `${String(first.text ?? '')}${extra}` };
  } else {
    content.push({ type: 'text', text: block });
  }
  return {
    ...userMessage,
    content,
    metadata: {
      ...(userMessage?.metadata ?? {}),
      agentVisible: userMessage?.metadata?.agentVisible ?? true,
    },
  };
}

export async function prefetchLiveSearchResults({
  query,
  selectedSkill,
  suggestedSkill,
  env = process.env,
  config = null,
  searchImpl = searchSearxng,
} = {}) {
  if (!shouldPrefetchLiveSearch({ selectedSkill, suggestedSkill, env })) {
    return null;
  }
  const q = String(query ?? '').trim();
  if (!q) return null;
  const endpoint = resolvePortalSearxngEndpoint(env, config);
  if (!endpoint) return null;
  try {
    const results = await searchImpl(q, {
      endpoint,
      limit: Number(env.TKMIND_SEARCH_MAX_RESULTS ?? 10) || 10,
      timeoutMs: Number(env.TKMIND_SEARCH_TIMEOUT_MS ?? 8000) || 8000,
    });
    const injectionText = formatPrefetchedSearchContext(results, { query: q });
    if (!injectionText) return null;
    return {
      provider: 'searxng',
      query: q,
      resultCount: Array.isArray(results) ? results.length : 0,
      injectionText,
    };
  } catch {
    return null;
  }
}

export async function defaultPrefetchLiveSearch({
  userMessage,
  routing = null,
  env = process.env,
} = {}) {
  const selectedSkill = String(
    userMessage?.metadata?.memindRun?.selectedChatSkill
      ?? userMessage?.metadata?.selectedChatSkill
      ?? '',
  ).trim();
  const suggestedSkill = String(routing?.suggestedSkill ?? routing?.suggested_skill ?? '').trim();
  const query = String(userMessage?.metadata?.displayText ?? '').trim();
  return prefetchLiveSearchResults({
    query,
    selectedSkill,
    suggestedSkill,
    env,
  });
}