*, *::before, *::after {
  box-sizing: border-box;
}

:root {
  --page: #eef2f7;
  --card: #ffffff;
  --text: #0f172a;
  --muted: #5b6678;
  --line: #d5dce6;
  --soft: #eef2f7;
  --accent: #2563eb;
  --live: #dc2626;
}

body {
  font-family: system-ui, "Segoe UI", Roboto, Helvetica, Arial, sans-serif;
  margin: 0;
  background: var(--page);
  color: var(--text);
}

.page {
  display: grid;
  grid-template-columns: minmax(0, 560px);
  justify-content: center;
  align-content: center;
  min-height: 100vh;
  padding: 24px 16px;
}

.dictate {
  padding: 20px;
  border-radius: 18px;
  background: var(--card);
  box-shadow: 0 1px 2px rgba(15, 23, 42, 0.05), 0 12px 32px -12px rgba(15, 23, 42, 0.2);
}

.dictate-head {
  display: flex;
  align-items: center;
  justify-content: space-between;
  gap: 12px;
  margin-bottom: 12px;
}

.dictate-title {
  margin: 0;
  font-size: 1.0625rem;
}

select {
  min-height: 36px;
  padding: 4px 8px;
  border: 1px solid var(--line);
  border-radius: 8px;
  background: var(--card);
  color: var(--text);
  font: inherit;
  font-size: 0.875rem;
}

textarea {
  display: block;
  width: 100%;
  min-height: 112px;
  padding: 12px 14px;
  border: 1px solid var(--line);
  border-radius: 12px;
  background: var(--card);
  color: var(--text);
  font: inherit;
  line-height: 1.55;
  resize: vertical;
}

textarea::placeholder {
  color: var(--muted);
}

select:focus-visible,
textarea:focus-visible,
.btn-clear:focus-visible,
.mic:focus-visible {
  outline: 2px solid var(--accent);
  outline-offset: 2px;
}

.interim {
  min-height: 1.5em;
  margin: 8px 2px 0;
  color: var(--muted);
  font-style: italic;
  line-height: 1.5;
}

.dictate-bar {
  display: flex;
  align-items: center;
  gap: 10px;
  margin-top: 8px;
}

.status {
  flex: 1;
  margin: 0;
  font-size: 0.875rem;
  color: var(--muted);
  line-height: 1.45;
}

.status.is-error {
  color: #b91c1c;
}

.btn-clear {
  min-height: 40px;
  padding: 6px 14px;
  border: 1px solid var(--line);
  border-radius: 10px;
  background: transparent;
  color: var(--text);
  font: inherit;
  font-size: 0.875rem;
  font-weight: 600;
  cursor: pointer;
}

.btn-clear:hover {
  background: var(--soft);
}

.mic {
  position: relative;
  display: grid;
  place-items: center;
  flex-shrink: 0;
  width: 52px;
  height: 52px;
  padding: 0;
  border: 0;
  border-radius: 50%;
  background: var(--text);
  color: var(--card);
  cursor: pointer;
  transition: background 0.2s ease;
}

.mic svg {
  width: 24px;
  height: 24px;
  fill: none;
  stroke: currentColor;
  stroke-width: 2;
  stroke-linecap: round;
  stroke-linejoin: round;
}

.mic[aria-pressed="true"] {
  background: var(--live);
  color: #ffffff;
}

.mic[aria-pressed="true"]::after {
  content: "";
  position: absolute;
  inset: 0;
  border-radius: 50%;
  box-shadow: 0 0 0 0 rgba(220, 38, 38, 0.45);
  animation: rec 1.6s ease-out infinite;
}

.mic:disabled {
  background: var(--line);
  color: var(--muted);
  cursor: not-allowed;
}

.sr-only {
  position: absolute;
  width: 1px;
  height: 1px;
  overflow: hidden;
  clip-path: inset(50%);
  white-space: nowrap;
}

@keyframes rec {
  to {
    box-shadow: 0 0 0 14px rgba(220, 38, 38, 0);
  }
}

@media (pointer: coarse) {
  .btn-clear,
  select {
    min-height: 44px;
  }
}

@media (prefers-color-scheme: dark) {
  :root {
    --page: #0b1120;
    --card: #151e30;
    --text: #e2e8f0;
    --muted: #a3afc2;
    --line: #334155;
    --soft: #1e293b;
    --accent: #60a5fa;
    --live: #ef4444;
  }

  .status.is-error {
    color: #fca5a5;
  }

  .mic[aria-pressed="true"] {
    color: #0b1120;
  }
}

@media (forced-colors: active) {
  .mic {
    border: 2px solid ButtonText;
  }

  .mic[aria-pressed="true"] {
    forced-color-adjust: none;
    border-color: Highlight;
    background: Highlight;
    color: HighlightText;
  }
}

@media (prefers-reduced-motion: reduce) {
  .mic[aria-pressed="true"]::after {
    animation: none;
  }
}

const Recognition = window.SpeechRecognition || window.webkitSpeechRecognition;

const errors = {
  "not-allowed": "Microphone access is blocked. Allow it in the site settings. Inside an iframe, the frame also needs microphone in its allow attribute.",
  "service-not-allowed": "The browser's speech service is turned off or not allowed on this page.",
  "audio-capture": "No microphone could be used. Check that one is connected and that this page is allowed to use it.",
  "no-speech": "No speech was heard. Press the mic and try again.",
  "network": "Speech recognition needs a network connection in this browser.",
  "language-not-supported": "That language is not supported here. Pick another one."
};

const textarea = document.getElementById("transcript");
const interim = document.getElementById("interim");
const status = document.getElementById("status");
const mic = document.getElementById("mic");
const clearBtn = document.getElementById("clear");
const lang = document.getElementById("lang");

let recognition = null;
let failed = false;

function setStatus(text, isError) {
  status.textContent = text;
  status.classList.toggle("is-error", Boolean(isError));
}

function setListening(on) {
  mic.setAttribute("aria-pressed", String(on));
  lang.disabled = on;
}

// Add a finished phrase to the end of the text box
function append(text, language) {
  const piece = text.trim();
  if (!piece) return;
  const end = textarea.value.length;
  const noSpace = /^(ja|zh)\b/i.test(language) || !end || /\s$/.test(textarea.value);
  textarea.setRangeText((noSpace ? "" : " ") + piece, end, end, "preserve");
  textarea.scrollTop = textarea.scrollHeight;
}

function start() {
  const rec = new Recognition();
  recognition = rec;
  failed = false;
  rec.lang = lang.value;
  rec.continuous = true;
  rec.interimResults = true;
  setListening(true);
  setStatus("Starting. Allow the microphone if the browser asks.");

  // Events from an older session are ignored
  rec.onstart = function() {
    if (recognition !== rec) return;
    setStatus("Listening. Press the mic again or Esc to stop.");
  };

  // Final results go into the box, the rest is a preview
  rec.onresult = function(e) {
    if (recognition !== rec) return;
    let preview = "";
    for (let i = e.resultIndex; i < e.results.length; i++) {
      const result = e.results[i];
      if (result.isFinal) {
        append(result[0].transcript, rec.lang);
      } else {
        preview += result[0].transcript;
      }
    }
    interim.textContent = preview;
  };

  rec.onerror = function(e) {
    if (recognition !== rec || e.error === "aborted") return;
    failed = true;
    setStatus(errors[e.error] || "Speech recognition stopped with the error " + e.error + ".", true);
  };

  rec.onend = function() {
    if (recognition !== rec) return;
    recognition = null;
    setListening(false);
    interim.textContent = "";
    if (!failed) setStatus("Stopped. Press the mic to keep dictating.");
  };

  try {
    rec.start();
  } catch (err) {
    recognition = null;
    setListening(false);
    setStatus("Speech recognition could not start. " + err.message, true);
  }
}

function stop() {
  if (recognition) recognition.stop();
}

if (!Recognition) {
  mic.disabled = true;
  setStatus("Speech recognition is not available in this browser. It works in Chrome, Edge and Safari.", true);
}

mic.addEventListener("click", function() {
  if (recognition) {
    stop();
  } else {
    start();
  }
});

clearBtn.addEventListener("click", function() {
  textarea.value = "";
  interim.textContent = "";
  textarea.focus();
});

document.addEventListener("keydown", function(e) {
  if (e.key === "Escape" && recognition) stop();
});