/**
 * Help Page — live API catalog, search, copy buttons, smooth navigation
 */

const API_BASE = window.location.origin;

class HelpPage {
  async init() {
    this.setupSearch();
    this.setupCopyButtons();
    this.setupToc();
    await this.loadLiveStats();
    await this.renderAiAgentGuide();
    await this.injectMaxProviderGuide();
    console.log('[Help] Ready with /api/max catalog');
  }

  async renderAiAgentGuide() {
    const panel = document.getElementById('ai-agent-panel');
    if (!panel) return;
    try {
      const help = await this.fetchJson('/api/max/help');
      const ai = help.for_ai_agents || {};
      const steps = (ai.query_algorithm || []).map(s => `<li>${s}</li>`).join('');
      const picks = Object.entries(ai.recommended_entrypoints || {}).map(
        ([k, v]) => `<tr><td><code>${k}</code></td><td><code>${v}</code></td></tr>`
      ).join('');
      const intentRows = (help.intent_map || []).slice(0, 12).map(intent => `
        <tr>
          <td><code>${intent.id}</code></td>
          <td>${intent.user_wants}</td>
          <td><code>${intent.method} ${intent.path}</code></td>
          <td>${(intent.keywords || []).slice(0, 4).join(', ')}</td>
        </tr>
      `).join('');
      panel.innerHTML = `
        <p><strong>${help.summary || ''}</strong></p>
        <p>${ai.read_this_first || ''}</p>
        <h3>Query algorithm</h3>
        <ol>${steps}</ol>
        <h3>Recommended entrypoints</h3>
        <table class="api-table">
          <thead><tr><th>Key</th><th>Endpoint</th></tr></thead>
          <tbody>${picks}</tbody>
        </table>
        <h3>Intent map (first 12 — full list in <a href="/api/max/help">/api/max/help</a>)</h3>
        <table class="api-table">
          <thead><tr><th>ID</th><th>User wants</th><th>Endpoint</th><th>Keywords</th></tr></thead>
          <tbody>${intentRows}</tbody>
        </table>
        <p>Search intents: <code>GET /api/max/help/intents?q=futures</code>
        &nbsp;|&nbsp; Download: <a href="/api/max/help/guide.json">guide.json</a></p>
      `;
    } catch (err) {
      panel.innerHTML = `<p class="help-note">Could not load AI guide: ${err.message}. Use <code>/api/max/help</code> directly.</p>`;
    }
  }

  setupSearch() {
    const input = document.getElementById('help-search');
    if (!input) return;
    input.addEventListener('input', (e) => {
      const q = e.target.value.toLowerCase().trim();
      document.querySelectorAll('.help-section').forEach((section) => {
        const text = section.textContent.toLowerCase();
        section.style.display = !q || text.includes(q) ? '' : 'none';
      });
    });
  }

  setupToc() {
    document.querySelectorAll('.help-toc a').forEach((link) => {
      link.addEventListener('click', (e) => {
        const id = link.getAttribute('href')?.slice(1);
        const el = id && document.getElementById(id);
        if (el) {
          e.preventDefault();
          el.scrollIntoView({ behavior: 'smooth', block: 'start' });
        }
      });
    });
  }

  setupCopyButtons(root = document) {
    root.querySelectorAll('[data-copy], .copy-btn').forEach((btn) => {
      if (btn.dataset.boundCopy === 'true') return;
      btn.dataset.boundCopy = 'true';
      btn.addEventListener('click', async () => {
        const text = btn.getAttribute('data-copy') || btn.closest('.code-wrap')?.querySelector('code')?.textContent;
        if (!text) return;
        try {
          await navigator.clipboard.writeText(text.trim());
          const label = btn.textContent;
          btn.textContent = 'Copied!';
          setTimeout(() => { btn.textContent = label; }, 1500);
        } catch {
          btn.textContent = 'Copy failed';
        }
      });
    });
  }

  async fetchJson(path, timeoutMs = 15000) {
    const controller = new AbortController();
    const timer = setTimeout(() => controller.abort(), timeoutMs);
    try {
      const res = await fetch(`${API_BASE}${path}`, { signal: controller.signal, headers: { Accept: 'application/json' } });
      if (!res.ok) throw new Error(`HTTP ${res.status}`);
      return await res.json();
    } finally {
      clearTimeout(timer);
    }
  }

  async loadLiveStats() {
    const el = document.getElementById('live-stats');
    if (!el) return;
    try {
      const [health, providers, pages, pressure] = await Promise.all([
        this.fetchJson('/api/max/health'),
        this.fetchJson('/api/max/providers/status?symbol=BTC'),
        this.fetchJson('/api/max/pages/functionality'),
        this.fetchJson('/api/max/pressure/status'),
      ]);
      const summary = health.summary || health.resource_registry || {};
      el.innerHTML = `
        <div class="stat-pill"><strong>${(summary.comprehensive_resources || 0) + (summary.unified_registry_entries || 0)}</strong><span>Resource entries</span></div>
        <div class="stat-pill"><strong>${providers.healthy_count ?? 0}/${providers.probed_count ?? 0}</strong><span>Provider probes</span></div>
        <div class="stat-pill"><strong>${pages.functional_count ?? 0}/${pages.total ?? 0}</strong><span>Functional pages</span></div>
        <div class="stat-pill"><strong>${(pressure.providers || []).length}</strong><span>Pressure-tracked providers</span></div>
        <div class="stat-pill"><strong>${health.cache?.entries ?? 0}</strong><span>Cache entries</span></div>
      `;
    } catch (err) {
      el.innerHTML = `<p class="help-note">Live /api/max stats unavailable (${err.message}). Check <code>/api/max/health</code> after the Space starts.</p>`;
    }
  }

  async injectMaxProviderGuide() {
    const main = document.querySelector('.help-main');
    if (!main || document.getElementById('max-provider-api')) return;
    let help;
    try {
      help = await this.fetchJson('/api/max/help');
    } catch (error) {
      help = {
        catalog: { endpoints: [] },
        examples: {
          health: 'curl $BASE/api/max/health',
          providers: "curl '$BASE/api/max/providers/status?symbol=BTC&include_slow=true'",
          visual: "curl '$BASE/api/max/system/visual?symbol=BTC'",
        },
        important_notes: [`Could not load live catalog: ${error.message}`],
      };
    }

    const toc = document.querySelector('.help-toc ul');
    if (toc && !toc.querySelector('a[href="#max-provider-api"]')) {
      const li = document.createElement('li');
      li.innerHTML = '<a href="#max-provider-api">Max Provider API</a>';
      toc.insertBefore(li, toc.children[2] || null);
    }

    const endpoints = help.catalog?.endpoints || [];
    const rows = endpoints.map(ep => `
      <tr>
        <td class="method-${String(ep.method || 'GET').toLowerCase()}">${ep.method || 'GET'}</td>
        <td><code>${ep.path}</code></td>
        <td>${ep.group || 'API'}</td>
        <td>${ep.purpose || ''}</td>
      </tr>
    `).join('');
    const examples = Object.entries(help.quick_examples || help.examples || {}).map(
      ([name, cmd]) => `${name}: ${String(cmd).replaceAll('{BASE}', API_BASE).replaceAll('$BASE', API_BASE)}`
    ).join('\n');
    const notes = (help.important_rules || help.important_notes || []).map(n => `<li>${n}</li>`).join('');

    const section = document.createElement('section');
    section.className = 'help-section';
    section.id = 'max-provider-api';
    section.innerHTML = `
      <h2>Max Provider API — Endpoint Catalog</h2>
      <p>Live from <code>/api/max/help</code> (schema v${help.schema_version || '1'}). ${help.intent_count || 0} intents mapped for AI agents.</p>
      <table class="api-table">
        <thead><tr><th>Method</th><th>Path</th><th>Group</th><th>Purpose</th></tr></thead>
        <tbody>${rows || '<tr><td colspan="4">Endpoint catalog unavailable.</td></tr>'}</tbody>
      </table>
      <div class="code-wrap">
        <button class="copy-btn" type="button">Copy</button>
        <pre class="code-block"><code>${examples || `curl ${API_BASE}/api/max/health`}</code></pre>
      </div>
      <h3>Runtime guarantees</h3>
      <ul>${notes}</ul>
    `;
    main.insertBefore(section, main.firstElementChild?.nextSibling || main.firstElementChild || null);
    this.setupCopyButtons(section);
    this.setupToc();
  }
}

export default HelpPage;