var typingMode = 'vocab';
var typingItems = [];
var typingIndex = 0;
var typingStats = { correct: 0, errors: 0 };
var typed = '';

var KEY_ROWS = [
  ['1','2','3','4','5','6','7','8','9','0'],
  ['q','w','e','r','t','y','u','i','o','p'],
  ['a','s','d','f','g','h','j','k','l','ñ'],
  ['z','x','c','v','b','n','m',',','.',';'],
  ['á','é','í','ó','ú','ü','¿','¡',':','?','!',' ']
];

function escTyping(s) {
  var div = document.createElement('div');
  div.textContent = s == null ? '' : String(s);
  return div.innerHTML;
}

function currentCategory() {
  var id = document.getElementById('category-select').value;
  return window.TYPING_DATA[typingMode].categories.find(function(c) {
    return c.id === id;
  });
}

function renderCategories() {
  var data = window.TYPING_DATA[typingMode];
  var select = document.getElementById('category-select');
  select.innerHTML = data.categories.map(function(cat) {
    return '<option value="' + escTyping(cat.id) + '">' +
      escTyping(cat.name) + '（' + cat.items.length + '）</option>';
  }).join('');
}

function startTyping() {
  var category = currentCategory();
  if (!category) return;
  var source = category.items.map(function(item, idx) {
    return Object.assign({}, item, { id: idx + 1 });
  });
  if (document.getElementById('order-select').value === 'random') {
    for (var i = source.length - 1; i > 0; i--) {
      var j = Math.floor(Math.random() * (i + 1));
      var t = source[i]; source[i] = source[j]; source[j] = t;
    }
  }
  var count = document.getElementById('count-select').value;
  typingItems = count === 'all' ? source : source.slice(0, parseInt(count, 10) || 10);
  typingIndex = 0;
  typingStats = { correct: 0, errors: 0 };
  typed = '';
  document.getElementById('typing-input').style.display = '';
  document.getElementById('setup-view').style.display = 'none';
  document.getElementById('practice-view').style.display = 'block';
  renderPractice();
}

function renderPractice() {
  if (typingIndex >= typingItems.length) {
    renderFinish();
    return;
  }
  var item = typingItems[typingIndex];
  var target = item.es;
  var targetHtml = '';
  for (var i = 0; i < target.length; i++) {
    var ch = escTyping(target[i]);
    if (i < typed.length) {
      targetHtml += '<span class="done">' + ch + '</span>';
    } else if (i === typed.length) {
      targetHtml += '<span class="current">' + ch + '</span>';
    } else {
      targetHtml += ch;
    }
  }
  document.getElementById('target-text').innerHTML = targetHtml;
  document.getElementById('chinese-text').textContent = item.zh || '';
  document.getElementById('progress-text').textContent =
    (typingIndex + 1) + ' / ' + typingItems.length;
  var totalKeys = typingStats.correct + typingStats.errors;
  document.getElementById('accuracy-text').textContent =
    '正确按键 ' + typingStats.correct + '，错误 ' + typingStats.errors +
    '，正确率 ' + (totalKeys ? Math.round(typingStats.correct * 100 / totalKeys) : 100) + '%';
  document.getElementById('progress-fill').style.width =
    (typingIndex * 100 / typingItems.length) + '%';

  var input = document.getElementById('typing-input');
  input.value = typed;
  renderNextKey(target);
  renderKeyboard(target);
  setTimeout(function() { input.focus(); }, 50);
}

function renderNextKey(target) {
  var next = target[typed.length];
  document.getElementById('next-key').innerHTML = typed.length >= target.length
    ? '已完成'
    : '下一键：<b>' + escTyping(next) + '</b>';
}

function renderTypingAccuracy() {
  var totalKeys = typingStats.correct + typingStats.errors;
  document.getElementById('accuracy-text').textContent =
    '正确按键 ' + typingStats.correct + '，错误 ' + typingStats.errors +
    '，正确率 ' + (totalKeys ? Math.round(typingStats.correct * 100 / totalKeys) : 100) + '%';
}

function renderKeyboard(target) {
  var next = target[typed.length] || '';
  var container = document.getElementById('keyboard');
  container.innerHTML = KEY_ROWS.map(function(row) {
    return '<div class="kb-row">' + row.map(function(key) {
      var label = key === ' ' ? '␣' : key;
      var isHint = next && (
        key === next ||
        key.toLowerCase() === next.toLowerCase() ||
        (next === ' ' && key === ' ')
      );
      return '<button type="button" class="kb-key' + (isHint ? ' hint' : '') + (key === ' ' ? ' space' : '') + '" data-key="' + escTyping(key) + '">' + escTyping(label) + '</button>';
    }).join('') + '</div>';
  }).join('');
}

function handleTypingInput() {
  var input = document.getElementById('typing-input');
  var value = input.value;
  var item = typingItems[typingIndex];
  if (!item) return;
  var target = item.es;
  var oldLength = typed.length;
  typed = value;
  if (target.indexOf(typed) === 0) {
    typingStats.correct += Math.max(0, typed.length - oldLength);
    renderTargetProgress(target);
  } else {
    typingStats.errors++;
    typed = target.slice(0, oldLength);
    input.value = typed;
    renderTargetProgress(target);
  }
  renderNextKey(target);
  renderTypingAccuracy();
  if (typed.length >= target.length) {
    typingStats.correct += Math.max(0, target.length - typed.length);
    speakText(item.es, 'es');
    typingIndex++;
    typed = '';
    setTimeout(renderPractice, 700);
  }
}

function renderTargetProgress(target) {
  var targetHtml = '';
  for (var i = 0; i < target.length; i++) {
    var ch = escTyping(target[i]);
    if (i < typed.length) {
      targetHtml += '<span class="done">' + ch + '</span>';
    } else if (i === typed.length) {
      targetHtml += '<span class="current">' + ch + '</span>';
    } else {
      targetHtml += ch;
    }
  }
  document.getElementById('target-text').innerHTML = targetHtml;
}

function renderFinish() {
  var totalKeys = typingStats.correct + typingStats.errors;
  var accuracy = totalKeys ? Math.round(typingStats.correct * 100 / totalKeys) : 100;
  document.getElementById('target-text').innerHTML = '';
  document.getElementById('chinese-text').textContent = '';
  document.getElementById('next-key').textContent = '';
  document.getElementById('keyboard').innerHTML = '';
  document.getElementById('progress-text').textContent = '';
  document.getElementById('accuracy-text').textContent = '';
  document.getElementById('typing-input').style.display = 'none';
  document.getElementById('progress-fill').style.width = '100%';
  document.getElementById('target-text').innerHTML =
    '<div class="finish-box"><h2>练习完成</h2><p>完成 ' + typingItems.length +
    ' 个，正确率 ' + accuracy + '%</p><button id="btn-again">再练一次</button></div>';
  document.getElementById('btn-again').addEventListener('click', function() {
    document.getElementById('typing-input').style.display = '';
    document.getElementById('setup-view').style.display = 'block';
    document.getElementById('practice-view').style.display = 'none';
  });
}

document.querySelectorAll('.mode-select button').forEach(function(btn) {
  btn.addEventListener('click', function() {
    typingMode = btn.dataset.mode;
    document.querySelectorAll('.mode-select button').forEach(function(b) {
      b.classList.toggle('active', b === btn);
    });
    renderCategories();
  });
});

document.getElementById('btn-start').addEventListener('click', startTyping);
document.getElementById('btn-restart').addEventListener('click', startTyping);
document.getElementById('typing-input').addEventListener('input', handleTypingInput);
document.getElementById('keyboard').addEventListener('click', function(e) {
  var btn = e.target.closest('.kb-key');
  if (!btn) return;
  var input = document.getElementById('typing-input');
  var key = btn.dataset.key;
  var next = typingItems[typingIndex] && typingItems[typingIndex].es[typed.length];
  if (next && key.toLowerCase() === next.toLowerCase() && key !== next) {
    key = next;
  }
  input.value += key;
  handleTypingInput();
  input.focus();
});

renderCategories();