/**
 * AgileHub — AI Assistant Widget (L1 Self-Service)
 * Embeddabile in qualsiasi prodotto della suite.
 *
 * Flusso: L1 AI (KB search) -> feedback -> L2 Formatore -> L3 Ticket
 *
 * Uso:
 *   <script src="js/ai-assistant.js"
 *     data-product="TRPG"
 *     data-tenant-id="3"
 *     data-api-url="https://agilehub.agile.software"
 *     data-user-name="Mario Rossi"
 *     data-user-email="mario@studio.it"
 *     data-user-role="consultant"
 *     data-lang="it">
 *   </script>
 *
 * Prerequisiti backend:
 *   - POST /api/support-sessions          (crea sessione)
 *   - POST /api/support-sessions/:id/message (AI risponde con KB)
 *   - POST /api/support-sessions/:id/resolve (feedback positivo)
 *   - POST /api/support-sessions/:id/forward-expert (escala L2)
 *   - POST /api/support-sessions/:id/escalate (escala L3 ticket)
 */
(function () {
  'use strict';

  // ==================== CONFIG ====================
  var script = document.currentScript || document.querySelector('script[data-product][data-api-url]');
  var CFG = {
    apiUrl:    (script && script.dataset.apiUrl) || '',
    product:   (script && script.dataset.product) || 'GENERIC',
    tenantId:  (script && script.dataset.tenantId) || '1',
    userName:  (script && script.dataset.userName) || '',
    userEmail: (script && script.dataset.userEmail) || '',
    userRole:  (script && script.dataset.userRole) || '',
    lang:      (script && script.dataset.lang) || 'it'
  };

  var LABELS = {
    it: {
      title: 'Assistente AgileHub',
      placeholder: 'Scrivi una domanda...',
      viewing: 'Stai guardando',
      suggestions_intro: 'Posso aiutarti con:',
      feedback_yes: 'Si, grazie',
      feedback_no: 'No, aiuto',
      escalation_title: 'Come posso aiutarti meglio?',
      btn_rephrase: 'Riformula la domanda',
      btn_expert: 'Chiedi al formatore',
      btn_bug: 'Segnala un bug',
      expert_sent: 'Domanda inoltrata al formatore. Riceverai una notifica quando la risposta sara pronta.',
      expert_time: 'Tempo stimato: entro 4 ore lavorative.',
      resolved_thanks: 'Grazie per il feedback! La tua valutazione migliora l\'assistente.',
      preparing: 'Mi sto preparando...',
      thinking: 'Sto pensando...',
      source: 'Fonte',
      resume: 'Riprendiamo la conversazione.',
      mic_unsupported: 'Microfono non supportato dal browser.',
      error_generic: 'Errore di connessione. Riprova tra poco.'
    },
    en: {
      title: 'AgileHub Assistant',
      placeholder: 'Ask a question...',
      viewing: 'You are viewing',
      suggestions_intro: 'I can help you with:',
      feedback_yes: 'Yes, thanks',
      feedback_no: 'No, help me',
      escalation_title: 'How can I help you better?',
      btn_rephrase: 'Rephrase question',
      btn_expert: 'Ask an expert',
      btn_bug: 'Report a bug',
      expert_sent: 'Your question has been forwarded to an expert. You\'ll be notified when the answer is ready.',
      expert_time: 'Estimated time: within 4 business hours.',
      resolved_thanks: 'Thanks for the feedback! Your rating improves the assistant.',
      preparing: 'Preparing...',
      thinking: 'Thinking...',
      source: 'Source',
      resume: 'Let\'s pick up where we left off.',
      mic_unsupported: 'Microphone not supported by this browser.',
      error_generic: 'Connection error. Please try again shortly.'
    }
  };

  function t(key) {
    var lang = CFG.lang;
    return (LABELS[lang] && LABELS[lang][key]) || (LABELS.it[key]) || key;
  }

  // ==================== STATE ====================
  var sessionId = null;
  var messages = [];     // { role: 'user'|'assistant'|'system', content, sources?, feedbackShown? }
  var panelOpen = false;
  var recognition = null;
  var isRecording = false;

  // ==================== API HELPERS ====================
  function apiHeaders() {
    var h = { 'Content-Type': 'application/json', 'x-tenant-id': CFG.tenantId };
    // Try to get JWT from the host app
    if (typeof Api !== 'undefined' && Api.auth && Api.auth.getToken) {
      var tok = Api.auth.getToken();
      if (tok) h['Authorization'] = 'Bearer ' + tok;
    }
    var stored = typeof localStorage !== 'undefined' ? localStorage.getItem('nexus_token') : null;
    if (!h['Authorization'] && stored) h['Authorization'] = 'Bearer ' + stored;
    return h;
  }

  function apiPost(path, body) {
    return fetch(CFG.apiUrl + path, {
      method: 'POST', headers: apiHeaders(), body: JSON.stringify(body)
    }).then(function (r) { return r.json(); });
  }

  function apiGet(path) {
    return fetch(CFG.apiUrl + path, { headers: apiHeaders() }).then(function (r) { return r.json(); });
  }

  // ==================== CONTEXT DETECTION ====================
  function detectPage() {
    // Try HelpSystem if available
    if (typeof HelpSystem !== 'undefined' && HelpSystem._detectPage) {
      return HelpSystem._detectPage();
    }
    // Fallback: extract from URL hash or path
    var hash = location.hash.replace('#', '').replace('/', '') || '';
    return hash || document.title || '';
  }

  function getContextualSuggestions() {
    if (typeof HelpSystem === 'undefined') return [];
    var page = typeof HelpSystem._detectPage === 'function' ? HelpSystem._detectPage() : null;
    var helpData = null;
    if (page && HelpSystem._helpContent) helpData = HelpSystem._helpContent[page];
    if (page && HelpSystem._help) {
      var raw = HelpSystem._help[page];
      if (raw) helpData = raw[CFG.lang] || raw.it || raw;
    }
    if (!helpData) return [];

    var suggestions = [];
    if (helpData.faq) {
      suggestions = helpData.faq.slice(0, 3).map(function (f) {
        return (typeof f === 'string') ? f : (f.question || f.q || '');
      });
    } else if (helpData.sections) {
      suggestions = helpData.sections.slice(0, 3).map(function (s) {
        if (!s.heading) return '';
        if (typeof s.heading === 'object') return s.heading[CFG.lang] || s.heading.it || '';
        return s.heading;
      });
    }
    return suggestions.filter(Boolean);
  }

  // ==================== SESSION MANAGEMENT ====================
  function createSession(cb) {
    apiPost('/api/support-sessions', {
      product: CFG.product,
      callerEmail: CFG.userEmail,
      callerName: CFG.userName
    }).then(function (res) {
      if (res.success && res.data) {
        sessionId = res.data.sessionId || res.data.id;
        if (res.data.welcomeMessage) {
          messages.push({ role: 'assistant', content: res.data.welcomeMessage });
        }
        // Store session for resume
        try { sessionStorage.setItem('agilehub_ai_session_' + CFG.product, sessionId); } catch (e) {}
      }
      if (cb) cb();
    }).catch(function () {
      messages.push({ role: 'system', content: t('error_generic') });
      if (cb) cb();
    });
  }

  function tryResumeSession(cb) {
    try {
      var stored = sessionStorage.getItem('agilehub_ai_session_' + CFG.product);
      if (stored) {
        sessionId = stored;
        messages.push({ role: 'system', content: t('resume') });
        cb(true);
        return;
      }
    } catch (e) {}
    cb(false);
  }

  function sendMessage(text, cb) {
    if (!sessionId) {
      createSession(function () { if (sessionId) sendMessage(text, cb); else cb(); });
      return;
    }
    messages.push({ role: 'user', content: text });
    render();

    apiPost('/api/support-sessions/' + sessionId + '/message', {
      content: text
    }).then(function (res) {
      if (res.success && res.data) {
        var reply = res.data.reply || res.data.message || res.data.answer || '';
        var sources = res.data.knowledgeArticles || res.data.sources || [];
        messages.push({ role: 'assistant', content: reply, sources: sources, feedbackShown: true });
      } else {
        messages.push({ role: 'assistant', content: (res.error && res.error.message) || t('error_generic') });
      }
      cb();
    }).catch(function () {
      messages.push({ role: 'assistant', content: t('error_generic') });
      cb();
    });
  }

  function resolveSession() {
    if (!sessionId) return;
    apiPost('/api/support-sessions/' + sessionId + '/resolve', {
      rating: 5, resolutionSummary: 'auto'
    });
  }

  function forwardToExpert(question, context) {
    if (!sessionId) return;
    return apiPost('/api/support-sessions/' + sessionId + '/forward-expert', {
      question: question, context: context
    });
  }

  function escalateToTicket(reason) {
    if (!sessionId) return;
    return apiPost('/api/support-sessions/' + sessionId + '/escalate', {
      reason: reason
    });
  }

  // ==================== VOICE INPUT ====================
  function initVoice() {
    var SR = window.SpeechRecognition || window.webkitSpeechRecognition;
    if (!SR) return null;
    recognition = new SR();
    recognition.lang = CFG.lang === 'en' ? 'en-US' : 'it-IT';
    recognition.interimResults = true;
    recognition.continuous = false;
    return recognition;
  }

  function toggleMic() {
    if (!recognition) {
      if (!initVoice()) {
        messages.push({ role: 'system', content: t('mic_unsupported') });
        render();
        return;
      }
    }
    if (isRecording) {
      recognition.stop();
      isRecording = false;
      render();
      return;
    }
    var input = document.getElementById('aia-input');
    recognition.onresult = function (e) {
      var transcript = '';
      for (var i = e.resultIndex; i < e.results.length; i++) {
        transcript += e.results[i][0].transcript;
      }
      if (input) input.value = transcript;
      if (e.results[e.results.length - 1].isFinal) {
        isRecording = false;
        render();
        if (transcript.trim()) submitInput(transcript.trim());
      }
    };
    recognition.onerror = function () { isRecording = false; render(); };
    recognition.onend = function () { isRecording = false; render(); };
    recognition.start();
    isRecording = true;
    render();
  }

  // ==================== RENDERING ====================
  function esc(s) {
    return String(s).replace(/[&<>"']/g, function (c) {
      return ({ '&': '&amp;', '<': '&lt;', '>': '&gt;', '"': '&quot;', "'": '&#39;' })[c];
    });
  }

  function renderMessages() {
    return messages.map(function (m, idx) {
      var isUser = m.role === 'user';
      var isSystem = m.role === 'system';

      var bubble = '<div style="margin-bottom:10px;display:flex;justify-content:'
        + (isUser ? 'flex-end' : 'flex-start') + '">'
        + '<div style="max-width:82%;padding:10px 14px;border-radius:14px;font-size:13px;line-height:1.5;'
        + 'background:' + (isUser ? 'linear-gradient(135deg,#7C3AED,#3B82F6)' : isSystem ? '#FEF3C7' : '#f3f4f6')
        + ';color:' + (isUser ? '#fff' : '#111827')
        + ';white-space:pre-wrap">'
        + esc(m.content);

      // Sources
      if (m.sources && m.sources.length > 0) {
        bubble += '<div style="margin-top:8px;padding-top:6px;border-top:1px solid rgba(0,0,0,.1);font-size:11px;color:#6B7280">';
        m.sources.forEach(function (s, si) {
          bubble += '<div>' + t('source') + ' [' + (si + 1) + '] ' + esc(s.question || s.title || '') + '</div>';
        });
        bubble += '</div>';
      }

      bubble += '</div></div>';

      // Feedback buttons
      if (m.feedbackShown && m.role === 'assistant' && idx === messages.length - 1) {
        bubble += '<div id="aia-feedback" style="display:flex;gap:8px;justify-content:flex-start;margin-bottom:10px">'
          + '<button onclick="window.__aiaFeedback(true)" style="padding:6px 14px;border-radius:8px;border:1px solid #D1D5DB;'
          + 'background:#fff;cursor:pointer;font-size:12px;color:#059669">&#x1F44D; ' + esc(t('feedback_yes')) + '</button>'
          + '<button onclick="window.__aiaFeedback(false)" style="padding:6px 14px;border-radius:8px;border:1px solid #D1D5DB;'
          + 'background:#fff;cursor:pointer;font-size:12px;color:#DC2626">&#x1F44E; ' + esc(t('feedback_no')) + '</button>'
          + '</div>';
      }

      return bubble;
    }).join('');
  }

  function renderEscalation() {
    return '<div id="aia-escalation" style="background:#F9FAFB;border-radius:12px;padding:14px;margin-bottom:10px">'
      + '<div style="font-weight:600;margin-bottom:10px;font-size:13px">' + esc(t('escalation_title')) + '</div>'
      + '<button onclick="window.__aiaEscalate(\'rephrase\')" style="display:block;width:100%;text-align:left;padding:10px 12px;'
      + 'border:1px solid #E5E7EB;border-radius:8px;background:#fff;cursor:pointer;margin-bottom:6px;font-size:12px">'
      + '&#x1F504; ' + esc(t('btn_rephrase')) + '</button>'
      + '<button onclick="window.__aiaEscalate(\'expert\')" style="display:block;width:100%;text-align:left;padding:10px 12px;'
      + 'border:1px solid #E5E7EB;border-radius:8px;background:#fff;cursor:pointer;margin-bottom:6px;font-size:12px">'
      + '&#x1F468;&#x200D;&#x1F3EB; ' + esc(t('btn_expert')) + '</button>'
      + '<button onclick="window.__aiaEscalate(\'bug\')" style="display:block;width:100%;text-align:left;padding:10px 12px;'
      + 'border:1px solid #E5E7EB;border-radius:8px;background:#fff;cursor:pointer;font-size:12px">'
      + '&#x1F41B; ' + esc(t('btn_bug')) + '</button>'
      + '</div>';
  }

  function render() {
    var panel = document.getElementById('aia-panel');
    if (!panel) return;

    var page = detectPage();
    var suggestions = (messages.length === 0) ? getContextualSuggestions() : [];
    var showEscalation = panel.dataset.showEscalation === '1';

    panel.innerHTML =
      // Header
      '<div style="padding:14px 16px;background:linear-gradient(135deg,#7C3AED,#3B82F6);color:#fff;'
      + 'display:flex;justify-content:space-between;align-items:center;border-radius:16px 16px 0 0">'
      + '<div style="display:flex;align-items:center;gap:8px;font-weight:600;font-size:14px">'
      + '<i class="fa-solid fa-wand-magic-sparkles"></i> ' + esc(t('title'))
      + '</div>'
      + '<button onclick="window.__aiaToggle()" style="background:none;border:none;color:#fff;font-size:18px;cursor:pointer">&times;</button>'
      + '</div>'

      // Context bar
      + (page ? '<div style="padding:8px 16px;background:#EDE9FE;font-size:11px;color:#6D28D9">'
      + '&#x1F4CD; ' + esc(t('viewing')) + ': <strong>' + esc(page) + '</strong></div>' : '')

      // Messages area
      + '<div id="aia-msgs" style="flex:1;overflow-y:auto;padding:14px 16px;background:#fafafa;min-height:200px">'
      + (messages.length === 0 && suggestions.length > 0
        ? '<div style="color:#6B7280;font-size:13px;margin-bottom:12px">' + esc(t('suggestions_intro')) + '</div>'
          + suggestions.map(function (s) {
              return '<button onclick="window.__aiaSuggest(\'' + esc(s).replace(/'/g, "\\'") + '\')" '
                + 'style="display:block;width:100%;text-align:left;padding:8px 12px;margin-bottom:6px;'
                + 'border:1px solid #E5E7EB;border-radius:8px;background:#fff;cursor:pointer;font-size:12px;color:#4B5563">'
                + '&#x1F4A1; ' + esc(s) + '</button>';
            }).join('')
        : '')
      + renderMessages()
      + (showEscalation ? renderEscalation() : '')
      + '</div>'

      // Input bar
      + '<form id="aia-form" onsubmit="return window.__aiaSubmit(event)" '
      + 'style="display:flex;gap:6px;padding:10px;border-top:1px solid #E5E7EB;background:#fff;border-radius:0 0 16px 16px">'
      + '<input id="aia-input" type="text" placeholder="' + esc(t('placeholder')) + '" autocomplete="off" '
      + 'style="flex:1;padding:10px 12px;border:1px solid #D1D5DB;border-radius:10px;font-size:13px;font-family:inherit">'
      + '<button type="button" onclick="window.__aiaMic()" style="padding:8px;border:none;border-radius:10px;'
      + 'background:' + (isRecording ? '#EF4444' : '#F3F4F6') + ';cursor:pointer;font-size:16px" title="Voce">'
      + (isRecording ? '&#x23F9;' : '&#x1F3A4;') + '</button>'
      + '<button type="submit" style="padding:8px 14px;border:none;border-radius:10px;'
      + 'background:linear-gradient(135deg,#7C3AED,#3B82F6);color:#fff;font-weight:600;cursor:pointer">'
      + '<i class="fa-solid fa-paper-plane"></i></button>'
      + '</form>';

    // Scroll to bottom
    var msgsEl = document.getElementById('aia-msgs');
    if (msgsEl) msgsEl.scrollTop = msgsEl.scrollHeight;
  }

  // ==================== HANDLERS ====================
  function submitInput(text) {
    if (!text) return;
    var input = document.getElementById('aia-input');
    if (input) input.value = '';
    var panel = document.getElementById('aia-panel');
    if (panel) panel.dataset.showEscalation = '0';

    // Show thinking
    messages.push({ role: 'assistant', content: t('thinking') });
    render();
    messages.pop(); // remove thinking

    sendMessage(text, function () { render(); });
  }

  window.__aiaToggle = function () {
    panelOpen = !panelOpen;
    var panel = document.getElementById('aia-panel');
    var fab = document.getElementById('ai-chat-fab');
    if (panel) panel.style.display = panelOpen ? 'flex' : 'none';
    if (fab) fab.style.display = panelOpen ? 'none' : 'flex';
    if (panelOpen && messages.length === 0) {
      tryResumeSession(function (resumed) {
        if (!resumed) {
          createSession(function () { render(); });
        } else {
          render();
        }
      });
    }
    if (panelOpen) render();
  };

  window.__aiaSubmit = function (e) {
    e.preventDefault();
    var input = document.getElementById('aia-input');
    var text = (input && input.value || '').trim();
    if (text) submitInput(text);
    return false;
  };

  window.__aiaSuggest = function (text) { submitInput(text); };
  window.__aiaMic = function () { toggleMic(); };

  window.__aiaFeedback = function (positive) {
    var fbEl = document.getElementById('aia-feedback');
    if (fbEl) fbEl.remove();

    if (positive) {
      resolveSession();
      messages.push({ role: 'system', content: t('resolved_thanks') });
      render();
    } else {
      // Show escalation options
      var panel = document.getElementById('aia-panel');
      if (panel) panel.dataset.showEscalation = '1';
      render();
    }
  };

  window.__aiaEscalate = function (action) {
    var panel = document.getElementById('aia-panel');
    if (panel) panel.dataset.showEscalation = '0';

    if (action === 'rephrase') {
      render();
      var input = document.getElementById('aia-input');
      if (input) input.focus();
      return;
    }

    if (action === 'expert') {
      var lastUserMsg = '';
      var lastAiMsg = '';
      for (var i = messages.length - 1; i >= 0; i--) {
        if (!lastAiMsg && messages[i].role === 'assistant') lastAiMsg = messages[i].content;
        if (!lastUserMsg && messages[i].role === 'user') lastUserMsg = messages[i].content;
        if (lastUserMsg && lastAiMsg) break;
      }
      forwardToExpert(lastUserMsg, lastAiMsg).then(function () {
        messages.push({ role: 'system', content: t('expert_sent') + '\n' + t('expert_time') });
        render();
      });
      return;
    }

    if (action === 'bug') {
      var reason = '';
      for (var j = messages.length - 1; j >= 0; j--) {
        if (messages[j].role === 'user') { reason = messages[j].content; break; }
      }
      escalateToTicket(reason).then(function () {
        messages.push({ role: 'system', content: 'Ticket tecnico creato. Il team di sviluppo lo prendera in carico.' });
        render();
      });
      return;
    }
  };

  // ==================== INIT ====================
  function init() {
    // Ensure FAB exists (may have been created by product's app.js)
    var fab = document.getElementById('ai-chat-fab');
    if (!fab) {
      fab = document.createElement('button');
      fab.id = 'ai-chat-fab';
      fab.setAttribute('aria-label', 'Chiedi ad ARIA');
      fab.style.cssText = 'position:fixed;bottom:24px;right:24px;width:56px;height:56px;'
        + 'border-radius:50%;border:none;cursor:pointer;z-index:9998;'
        + 'background:linear-gradient(135deg,#7C3AED,#3B82F6);color:#fff;'
        + 'box-shadow:0 6px 20px rgba(124,58,237,.4);font-size:22px;'
        + 'display:flex;align-items:center;justify-content:center';
      fab.innerHTML = '<i class="fa-solid fa-wand-magic-sparkles"></i>';
      document.body.appendChild(fab);
    } else {
      // Rimuovi il vecchio pannello AI del prodotto (evita doppia finestra)
      var oldPanel = document.getElementById('ai-chat-panel');
      if (oldPanel) oldPanel.remove();

      // Clona il FAB per eliminare TUTTI gli addEventListener precedenti
      var cleanFab = fab.cloneNode(true);
      fab.parentNode.replaceChild(cleanFab, fab);
      fab = cleanFab;
    }
    fab.style.display = 'flex';
    fab.style.alignItems = 'center';
    fab.style.justifyContent = 'center';
    fab.onclick = window.__aiaToggle;

    // Ensure panel exists
    var panel = document.getElementById('aia-panel');
    if (!panel) {
      panel = document.createElement('div');
      panel.id = 'aia-panel';
      panel.style.cssText = 'position:fixed;bottom:90px;right:24px;width:380px;max-height:560px;'
        + 'background:#fff;border-radius:16px;box-shadow:0 12px 32px rgba(0,0,0,.2);'
        + 'display:none;z-index:9999;overflow:hidden;flex-direction:column;'
        + 'font-family:-apple-system,BlinkMacSystemFont,\"Segoe UI\",Roboto,sans-serif';
      document.body.appendChild(panel);
    }
    panel.dataset.showEscalation = '0';
  }

  // Auto-init when DOM is ready
  if (document.readyState === 'loading') {
    document.addEventListener('DOMContentLoaded', init);
  } else {
    init();
  }
})();