(function () {
  'use strict';

  const GLYPHS = {
    note: '◦', todo: '▸', event: '◇',
    snippet: '◆', template: '◈', checklist: '☐',
    decision: '⚖', link: '🔗',
  };

  const GLYPH_CLASSES = {
    note: 'glyph-note', todo: 'glyph-todo', event: 'glyph-event',
    snippet: 'glyph-snippet', template: 'glyph-template',
    checklist: 'glyph-checklist', decision: 'glyph-decision',
    link: 'glyph-link',
  };

  const state = {
    view: 'stream',
    entities: [],
    tags: [],
    selectedIndex: -1,
    activeTag: null,
  };

  const $ = (sel) => document.querySelector(sel);
  const $$ = (sel) => document.querySelectorAll(sel);

  // ========== API ==========

  const api = {
    async listEntities(params = {}) {
      const q = new URLSearchParams();
      if (params.tag) q.set('tag', params.tag);
      if (params.date) q.set('date', params.date);
      if (params.cards_only) q.set('cards_only', 'true');
      if (params.sort) q.set('sort', params.sort);
      if (params.order) q.set('order', params.order);
      const resp = await fetch('/api/entities?' + q);
      return resp.json();
    },
    async createEntity(data) {
      const resp = await fetch('/api/entities', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(data),
      });
      return resp.json();
    },
    async getEntity(id) {
      const resp = await fetch('/api/entities/' + id);
      return resp.json();
    },
    async updateEntity(id, data) {
      const resp = await fetch('/api/entities/' + id, {
        method: 'PUT',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify(data),
      });
      return resp.json();
    },
    async deleteEntity(id) {
      return fetch('/api/entities/' + id, { method: 'DELETE' });
    },
    async promoteEntity(id, cardType, cardData) {
      const resp = await fetch('/api/entities/' + id + '/promote', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({ card_type: cardType, card_data: cardData }),
      });
      return resp.json();
    },
    async demoteEntity(id) {
      const resp = await fetch('/api/entities/' + id + '/demote', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({}),
      });
      return resp.json();
    },
    async useEntity(id) {
      const resp = await fetch('/api/entities/' + id + '/use', {
        method: 'POST',
        headers: { 'Content-Type': 'application/json' },
        body: JSON.stringify({}),
      });
      return resp.json();
    },
    async listTags() {
      const resp = await fetch('/api/tags');
      return resp.json();
    },
  };

  // ========== Grammar parser (mirrors Go parser) ==========

  const VALID_CARDS = { card: 'snippet', c: 'snippet', snippet: 'snippet', template: 'template', checklist: 'checklist', decision: 'decision', link: 'link' };

  function parseInput(input) {
    input = input.trim();
    if (!input) return null;

    const tokens = input.split(/\s+/);
    let glyph = 'note';

    const first = tokens[0];
    if (first === '-' || first === '▸') { glyph = 'todo'; tokens.shift(); }
    else if (first === '*' || first === '◇') { glyph = 'event'; tokens.shift(); }

    const bodyParts = [];
    let timeAnchor = null;
    const tags = [];
    const seenTags = {};
    let cardSuffix = null;

    for (const tok of tokens) {
      if (tok.startsWith('@') && tok.length > 1) {
        timeAnchor = tok.slice(1);
      } else if (tok.startsWith('#') && tok.length > 1) {
        const tag = tok.slice(1);
        if (!seenTags[tag]) { tags.push(tag); seenTags[tag] = true; }
      } else if (tok.startsWith('^') && tok.length > 1) {
        const suffix = tok.slice(1);
        if (VALID_CARDS[suffix]) cardSuffix = VALID_CARDS[suffix];
      } else {
        bodyParts.push(tok);
      }
    }

    const body = bodyParts.join(' ');
    if (!body) return null;

    return { body, glyph, timeAnchor, tags, cardSuffix };
  }

  function detectCardType(body) {
    if (/\$\{.+\}/.test(body)) return 'template';
    if (/\bchose:|why:/.test(body)) return 'decision';
    if (/\[ \]|\d+\./.test(body)) return 'checklist';
    if (/https?:\/\//.test(body)) return 'link';
    return null;
  }

  // ========== Rendering ==========

  function displayGlyph(entity) {
    return entity.card_type ? GLYPHS[entity.card_type] : GLYPHS[entity.glyph];
  }

  function glyphClass(entity) {
    return entity.card_type ? GLYPH_CLASSES[entity.card_type] : GLYPH_CLASSES[entity.glyph];
  }

  function formatDate(dateStr) {
    const d = new Date(dateStr);
    const months = ['jan', 'feb', 'mar', 'apr', 'may', 'jun', 'jul', 'aug', 'sep', 'oct', 'nov', 'dec'];
    return months[d.getMonth()] + ' ' + d.getDate();
  }

  function renderTagRail() {
    const rail = $('#tag-rail');
    const allItem = `<div class="tag-item ${!state.activeTag ? 'active' : ''}" data-tag="">
      <span class="tag-name" style="font-style: italic">all</span>
    </div>`;

    rail.innerHTML = allItem + state.tags.map(t =>
      `<div class="tag-item ${state.activeTag === t.tag ? 'active' : ''}" data-tag="${t.tag}">
        <span class="tag-name">${t.tag}</span>
        <span class="tag-count">${t.count}</span>
      </div>`
    ).join('');

    rail.querySelectorAll('.tag-item').forEach(el => {
      el.addEventListener('click', () => {
        state.activeTag = el.dataset.tag || null;
        loadEntities();
        renderTagRail();
      });
    });
  }

  function groupByDate(entities) {
    const groups = [];
    let current = null;
    for (const e of entities) {
      const label = formatDate(e.created_at);
      if (!current || current.label !== label) {
        if (current) groups.push(current);
        current = { label, entities: [] };
      }
      current.entities.push(e);
    }
    if (current) groups.push(current);
    return groups;
  }

  function renderEntityList() {
    const list = $('#entity-list');

    if (state.entities.length === 0) {
      list.innerHTML = '<div class="detail-empty" style="margin-top:40px">no entities yet</div>';
      return;
    }

    let html = '';
    if (state.view === 'stream') {
      const groups = groupByDate(state.entities);
      let idx = 0;
      for (const g of groups) {
        html += `<div class="date-header">── ${g.label} ──</div>`;
        for (const e of g.entities) {
          html += renderEntityItem(e, idx);
          idx++;
        }
      }
    } else {
      state.entities.forEach((e, idx) => {
        html += renderEntityItem(e, idx);
      });
    }

    list.innerHTML = html;

    list.querySelectorAll('.entity-item').forEach(el => {
      el.addEventListener('click', () => {
        selectEntity(parseInt(el.dataset.index));
      });
    });
  }

  function renderEntityItem(e, idx) {
    const glyph = displayGlyph(e);
    const gc = glyphClass(e);
    const selected = idx === state.selectedIndex ? 'selected' : '';
    const tags = (e.tags || []).map(t => `<span class="entity-tag">${t}</span>`).join('');
    const time = e.time_anchor ? `<span class="entity-time">@${e.time_anchor}</span>` : '';
    const useBadge = e.use_count > 0 ? `<span class="use-badge">${e.use_count}×</span>` : '';

    return `<div class="entity-item ${selected}" data-index="${idx}" data-id="${e.id}">
      <span class="entity-glyph ${gc}">${glyph}</span>
      <span class="entity-body">${escHtml(e.body)}</span>
      ${time}
      <span class="entity-tags">${tags}</span>
      <span class="entity-meta">${useBadge}</span>
    </div>`;
  }

  function renderDetailPane() {
    const pane = $('#detail-pane');
    const e = state.entities[state.selectedIndex];

    if (!e) {
      pane.innerHTML = '<div class="detail-empty">select an entity</div>';
      pane.classList.remove('visible');
      return;
    }

    pane.classList.add('visible');
    const glyph = displayGlyph(e);
    const gc = glyphClass(e);
    const tags = (e.tags || []).map(t => `<span class="detail-tag">#${t}</span>`).join('');
    const shortId = e.id.slice(0, 12);

    let cardContent = '';
    let actions = '';

    if (e.card_type) {
      cardContent = renderCardContent(e);
      actions += `<button class="action-btn" onclick="nibApp.copyEntity('${e.id}')">copy</button>`;
      actions += `<button class="action-btn" onclick="nibApp.demoteEntity('${e.id}')">demote</button>`;
    } else {
      actions += `<button class="action-btn primary" onclick="nibApp.showPromote('${e.id}')">promote</button>`;
    }
    actions += `<button class="action-btn danger" onclick="nibApp.deleteEntity('${e.id}')">delete</button>`;

    pane.innerHTML = `
      <div class="detail-header">
        <span class="detail-glyph ${gc}">${glyph}</span>
        <span class="detail-id">${shortId}</span>
        ${e.time_anchor ? `<span class="entity-time">@${e.time_anchor}</span>` : ''}
      </div>
      <div class="detail-body">${escHtml(e.body)}</div>
      ${tags ? `<div class="detail-tags">${tags}</div>` : ''}
      ${cardContent}
      <div class="detail-actions">${actions}</div>
    `;
  }

  function renderCardContent(e) {
    if (!e.card_data) return '';
    let data;
    try { data = JSON.parse(e.card_data); } catch { return ''; }

    switch (e.card_type) {
      case 'template':
        if (!data.slots || !data.slots.length) return '';
        return `<div class="slot-form">
          ${data.slots.map(s => `
            <div class="slot-field">
              <span class="slot-label">\${${s.name}}</span>
              <input class="slot-input" data-slot="${s.name}" placeholder="${s.default || s.name}" value="${s.default || ''}">
            </div>
          `).join('')}
          <button class="action-btn primary" onclick="nibApp.resolveTemplate('${e.id}')">resolve & copy</button>
        </div>`;

      case 'checklist':
        if (!data.steps || !data.steps.length) return '';
        return `<div class="checklist">
          ${data.steps.map((s, i) => `
            <div class="checklist-step ${s.done ? 'done' : ''}">
              <input type="checkbox" ${s.done ? 'checked' : ''} onchange="nibApp.toggleStep('${e.id}', ${i})">
              <span>${escHtml(s.text)}</span>
            </div>
          `).join('')}
        </div>`;

      case 'decision':
        return `<div>
          <div class="decision-field"><div class="decision-label">chose</div><div class="decision-value">${escHtml(data.chose || '—')}</div></div>
          <div class="decision-field"><div class="decision-label">why</div><div class="decision-value">${escHtml(data.why || '—')}</div></div>
          ${data.rejected && data.rejected.length ? `<div class="decision-field"><div class="decision-label">rejected</div><div class="decision-value">${data.rejected.map(escHtml).join(', ') || '—'}</div></div>` : ''}
        </div>`;

      case 'link':
        if (data.url) {
          return `<div style="margin-bottom:12px">
            <button class="action-btn" onclick="window.open('${escAttr(data.url)}', '_blank')">open link</button>
          </div>`;
        }
        return '';

      default:
        return '';
    }
  }

  // ========== Actions ==========

  function selectEntity(idx) {
    state.selectedIndex = idx;
    renderEntityList();
    renderDetailPane();
  }

  async function loadEntities() {
    const params = {};
    if (state.activeTag) params.tag = state.activeTag;
    if (state.view === 'cards') {
      params.cards_only = true;
      params.sort = 'use_count';
      params.order = 'desc';
    } else {
      params.sort = 'created';
      params.order = 'desc';
    }

    state.entities = await api.listEntities(params);
    state.selectedIndex = -1;
    renderEntityList();
    renderDetailPane();
  }

  async function loadTags() {
    state.tags = await api.listTags();
    renderTagRail();
  }

  function switchView(view) {
    state.view = view;
    $$('.nav-btn').forEach(b => b.classList.toggle('active', b.dataset.view === view));
    window.location.hash = view === 'cards' ? '/cards' : '/';
    loadEntities();
  }

  // ========== Public API (for inline handlers) ==========

  window.nibApp = {
    async copyEntity(id) {
      const e = state.entities.find(x => x.id === id);
      if (!e) return;
      try {
        await navigator.clipboard.writeText(e.body);
        await api.useEntity(id);
        await loadEntities();
      } catch (err) {
        console.error('clipboard:', err);
      }
    },

    showPromote(id) {
      const e = state.entities.find(x => x.id === id);
      if (!e || e.card_type) return;

      const modal = $('#promote-modal');
      modal.classList.remove('hidden');
      modal.classList.add('visible');
      modal.dataset.entityId = id;

      const suggested = detectCardType(e.body);
      $$('.type-btn').forEach(btn => {
        btn.classList.toggle('suggested', btn.dataset.type === suggested);
      });
    },

    async demoteEntity(id) {
      await api.demoteEntity(id);
      await loadEntities();
      await loadTags();
    },

    async deleteEntity(id) {
      await api.deleteEntity(id);
      await loadEntities();
      await loadTags();
    },

    async resolveTemplate(id) {
      const e = state.entities.find(x => x.id === id);
      if (!e) return;
      let resolved = e.body;
      $$('.slot-input').forEach(input => {
        const name = input.dataset.slot;
        const val = input.value || input.placeholder;
        resolved = resolved.replace(new RegExp('\\$\\{' + name + '\\}', 'g'), val);
      });
      try {
        await navigator.clipboard.writeText(resolved);
        await api.useEntity(id);
        await loadEntities();
      } catch (err) {
        console.error('clipboard:', err);
      }
    },

    async toggleStep(id, stepIdx) {
      const e = state.entities.find(x => x.id === id);
      if (!e || !e.card_data) return;
      const data = JSON.parse(e.card_data);
      data.steps[stepIdx].done = !data.steps[stepIdx].done;
      await api.updateEntity(id, { card_data: JSON.stringify(data) });
      await loadEntities();
      selectEntity(state.entities.findIndex(x => x.id === id));
    },
  };

  // ========== Capture bar ==========

  $('#capture-bar').addEventListener('submit', async (ev) => {
    ev.preventDefault();
    const input = $('#capture-input');
    const val = input.value.trim();
    if (!val) return;

    const parsed = parseInput(val);
    if (!parsed) return;

    const data = {
      body: parsed.body,
      glyph: parsed.glyph,
      tags: parsed.tags,
    };
    if (parsed.timeAnchor) data.time_anchor = parsed.timeAnchor;
    if (parsed.cardSuffix) data.card_type = parsed.cardSuffix;

    await api.createEntity(data);
    input.value = '';
    await loadEntities();
    await loadTags();
  });

  // ========== Promote modal ==========

  $$('.type-btn').forEach(btn => {
    btn.addEventListener('click', async () => {
      const modal = $('#promote-modal');
      const id = modal.dataset.entityId;
      modal.classList.add('hidden');
      modal.classList.remove('visible');

      await api.promoteEntity(id, btn.dataset.type);
      await loadEntities();
      await loadTags();
    });
  });

  $('.modal-backdrop').addEventListener('click', closeModal);
  $('.modal-close').addEventListener('click', closeModal);

  function closeModal() {
    const modal = $('#promote-modal');
    modal.classList.add('hidden');
    modal.classList.remove('visible');
  }

  // ========== Keyboard shortcuts ==========

  let lastDTime = 0;
  const captureInput = $('#capture-input');

  document.addEventListener('keydown', (ev) => {
    if (document.activeElement === captureInput) {
      if (ev.key === 'Escape') captureInput.blur();
      return;
    }

    if ($('#promote-modal').classList.contains('visible')) {
      if (ev.key === 'Escape') closeModal();
      return;
    }

    switch (ev.key) {
      case 'j':
        ev.preventDefault();
        selectEntity(Math.min(state.selectedIndex + 1, state.entities.length - 1));
        scrollSelectedIntoView();
        break;
      case 'k':
        ev.preventDefault();
        selectEntity(Math.max(state.selectedIndex - 1, 0));
        scrollSelectedIntoView();
        break;
      case 'n':
        ev.preventDefault();
        captureInput.focus();
        break;
      case 'p': {
        const e = state.entities[state.selectedIndex];
        if (e && !e.card_type) nibApp.showPromote(e.id);
        break;
      }
      case 'Enter': {
        const e = state.entities[state.selectedIndex];
        if (e) nibApp.copyEntity(e.id);
        break;
      }
      case 'd': {
        const now = Date.now();
        if (now - lastDTime < 400) {
          const e = state.entities[state.selectedIndex];
          if (e) nibApp.deleteEntity(e.id);
          lastDTime = 0;
        } else {
          lastDTime = now;
        }
        break;
      }
      case '1': switchView('stream'); break;
      case '2': switchView('cards'); break;
    }
  });

  function scrollSelectedIntoView() {
    const el = $(`.entity-item[data-index="${state.selectedIndex}"]`);
    if (el) el.scrollIntoView({ block: 'nearest' });
  }

  // ========== View nav buttons ==========

  $$('.nav-btn').forEach(btn => {
    btn.addEventListener('click', () => switchView(btn.dataset.view));
  });

  // ========== Hash routing ==========

  function handleHash() {
    const hash = window.location.hash;
    if (hash === '#/cards') {
      state.view = 'cards';
    } else {
      state.view = 'stream';
    }
    $$('.nav-btn').forEach(b => b.classList.toggle('active', b.dataset.view === state.view));
    loadEntities();
  }

  window.addEventListener('hashchange', handleHash);

  // ========== Utils ==========

  function escHtml(s) {
    if (!s) return '';
    return s.replace(/&/g, '&amp;').replace(/</g, '&lt;').replace(/>/g, '&gt;').replace(/"/g, '&quot;');
  }

  function escAttr(s) {
    return escHtml(s).replace(/'/g, '&#39;');
  }

  // ========== Init ==========

  async function init() {
    await Promise.all([loadEntities(), loadTags()]);
    handleHash();
  }

  init();
})();