// UI elements.
const input = document.getElementById("channelInput");
const linkInput = document.getElementById("channelLinkInput");
const addBtn = document.getElementById("addBtn");
const list = document.getElementById("channelList");
const debugToggle = document.getElementById("debugToggle");
const resetBtn = document.getElementById("resetBtn");

// Default settings payload.
const DEFAULTS = {
  whitelist: [],
  debug: false
};

// Render whitelist and debug state.
function loadChannels() {
  chrome.storage.local.get(DEFAULTS, ({ whitelist, debug }) => {
    list.innerHTML = "";
    debugToggle.checked = Boolean(debug);
    const entries = normalizeWhitelist(whitelist);
    entries.forEach((entry, index) => {
      const li = document.createElement("li");
      const text = entry.handle
        ? `${entry.name} (@${entry.handle})`
        : entry.name;
      li.textContent = text;

      const remove = document.createElement("button");
      remove.textContent = "x";
      remove.onclick = () => removeChannel(index);

      li.appendChild(remove);
      list.appendChild(li);
    });
  });
}

// Add a new whitelist entry with name + handle.
function addChannel() {
  const name = input.value.trim();
  const link = linkInput.value.trim();
  if (!name || !link) return;
  const handle = normalizeHandle(link);
  if (!handle) return;

  chrome.storage.local.get(DEFAULTS, ({ whitelist }) => {
    const entries = normalizeWhitelist(whitelist);
    entries.push({ name, handle });
    chrome.storage.local.set({ whitelist: entries }, loadChannels);
  });

  input.value = "";
  linkInput.value = "";
}

// Normalize storage entries to { name, handle } objects.
function normalizeWhitelist(whitelist) {
  return (whitelist || []).map(item => {
    if (typeof item === "string") {
      return { name: item, handle: "" };
    }
    return { name: item.name || "", handle: item.handle || "" };
  });
}

// Remove a whitelist entry by index.
function removeChannel(index) {
  chrome.storage.local.get(DEFAULTS, ({ whitelist }) => {
    const entries = normalizeWhitelist(whitelist);
    entries.splice(index, 1);
    chrome.storage.local.set({ whitelist: entries }, loadChannels);
  });
}

// Persist debug toggle.
function setDebug(enabled) {
  chrome.storage.local.set({ debug: Boolean(enabled) });
}

// Reset all settings to defaults.
function resetDefaults() {
  chrome.storage.local.set(DEFAULTS, loadChannels);
}

// Accept @handle or full channel URL.
function normalizeHandle(value) {
  const atMatch = value.match(/@([^/?#]+)/);
  if (atMatch) return atMatch[1].trim();
  const clean = value.replace(/^https?:\/\//i, "").trim();
  const urlMatch = clean.match(/youtube\.com\/@([^/?#]+)/i);
  if (urlMatch) return urlMatch[1].trim();
  return "";
}

// Wire UI events.
addBtn.onclick = addChannel;
debugToggle.onchange = e => setDebug(e.target.checked);
resetBtn.onclick = resetDefaults;
loadChannels();