/* The settings panel: a gear, and what is behind it.
 *
 * Inline, never a pop-up — it opens by pushing the table down, the same way
 * everything else on this page reports itself. Animation speed is always here
 * (it exists because the alternative was letting the operating system decide —
 * see animate.js for that story); a page that shows score pop-ups asks for
 * their switch with `{popups: true}`, a page that places moves before
 * playing them asks for the confirm switch with `{confirm: true}`, and a
 * page with the side-by-side table asks for the board-size − / + row with
 * `{boards: true}` (see layout.js).
 *
 *   const settings = createSettings(host);                  // speed only
 *   const settings = createSettings(host, {popups: true, confirm: true});
 *
 * Every control reads its stored value through its own module and writes it
 * back on every click, so a reload keeps whatever you chose.
 */

import { SPEEDS, initSpeed, setSpeed, speed } from "./animate.js";
import { confirmOn, initConfirm, setConfirm } from "./confirm.js";
import { boardsMode, initBoards, setBoardsMode } from "./layout.js";
import { initPopups, popupsOn, setPopups } from "./popups.js";
import { node } from "./dom.js";

const LABELS = { 0: "Off", 0.5: "0.5×", 1: "1×", 2: "2×" };
const TITLES = {
  0: "No tile animation: positions change at once",
  0.5: "Half speed: every tile easy to follow",
  1: "The default pace",
  2: "Twice as fast",
};

/* A gear, drawn rather than fetched — this page never asks the network for a
 * byte, not even an icon. Parsed as HTML so the SVG namespace comes for free
 * and this file need not name a URL of any kind. */
const GEAR_SVG =
  '<svg viewBox="0 0 24 24" class="gear-icon" aria-hidden="true"><path d="' +
  "M12 8.4a3.6 3.6 0 1 0 0 7.2 3.6 3.6 0 0 0 0-7.2zm9 4.9v-2.6l-2.4-.4a6.9 6.9 0 0 0-.8-1.9" +
  "l1.4-2-1.8-1.8-2 1.4a6.9 6.9 0 0 0-1.9-.8L13.1 3h-2.6l-.4 2.4a6.9 6.9 0 0 0-1.9.8l-2-1.4" +
  "-1.8 1.8 1.4 2a6.9 6.9 0 0 0-.8 1.9L3 10.7v2.6l2.4.4c.2.7.4 1.3.8 1.9l-1.4 2 1.8 1.8 2-1.4" +
  "c.6.4 1.2.6 1.9.8l.4 2.4h2.6l.4-2.4c.7-.2 1.3-.4 1.9-.8l2 1.4 1.8-1.8-1.4-2c.4-.6.6-1.2.8-1.9l2.4-.4z" +
  '"/></svg>';

function gearIcon() {
  const holder = document.createElement("span");
  holder.innerHTML = GEAR_SVG;
  return holder.firstChild;
}

export function createSettings(host, options = {}) {
  host.classList.add("settings");
  host.innerHTML = "";

  const head = node("div", "settings-head");
  const gear = node("button", "gear");
  gear.type = "button";
  gear.setAttribute("aria-expanded", "false");
  gear.appendChild(gearIcon());
  gear.appendChild(node("span", null, "Settings"));
  const summary = node("span", "settings-note", "");
  head.append(gear, summary);

  const panel = node("div", "settings-panel");
  panel.hidden = true;
  const label = node("span", "settings-label", "Tile animation");
  const speeds = node("div", "speeds");
  speeds.setAttribute("role", "group");
  speeds.setAttribute("aria-label", "Animation speed");
  const hint = node("p", "settings-hint", "");
  panel.append(label, speeds, hint);

  const buttons = SPEEDS.map((value) => {
    const b = node("button", "speed", LABELS[value]);
    b.type = "button";
    b.dataset.speed = String(value);
    b.title = TITLES[value];
    b.addEventListener("click", () => {
      setSpeed(value);
      sync();
      if (options.onChange) options.onChange(value);
    });
    speeds.appendChild(b);
    return b;
  });

  /** One On/Off pair in the panel, wired to a stored preference. */
  function flagRow(label, dataKey, titles, get, set) {
    panel.append(node("i", "settings-gap"), node("span", "settings-label", label));
    const flags = node("div", "speeds");
    flags.setAttribute("role", "group");
    flags.setAttribute("aria-label", label);
    const pair = [true, false].map((value) => {
      const b = node("button", "flag", value ? "On" : "Off");
      b.type = "button";
      b.dataset[dataKey] = String(value);
      b.title = titles[value ? 0 : 1];
      b.addEventListener("click", () => {
        set(value);
        sync();
        if (options.onChange) options.onChange(speed());
      });
      flags.appendChild(b);
      return b;
    });
    panel.append(flags);
    return { pair, get, dataKey };
  }

  const flagRows = [];
  if (options.popups) {
    initPopups();
    flagRows.push(
      flagRow(
        "Score pop-ups",
        "pops",
        [
          "Every point floats off the square that earned it as the round is scored",
          "Scoring stays in the panel below the boards",
        ],
        popupsOn,
        setPopups
      )
    );
  }
  if (options.confirm) {
    initConfirm();
    flagRows.push(
      flagRow(
        "Confirm each move",
        "confirm",
        [
          "Clicking a row places the tiles; the move plays only when you confirm it",
          "Clicking a row plays the move at once",
        ],
        confirmOn,
        setConfirm
      )
    );
  }

  /* Board size is a − / + pair, not On/Off: − keeps the whole game on one
   * screen (factories left, both boards beside them), + gives the big boards
   * back, one under the other. The page's stylesheet reads the choice off
   * <body data-boards>. */
  let boardButtons = [];
  if (options.boards) {
    initBoards();
    panel.append(node("i", "settings-gap"), node("span", "settings-label", "Board size"));
    const sizes = node("div", "speeds");
    sizes.setAttribute("role", "group");
    sizes.setAttribute("aria-label", "Board size");
    boardButtons = [
      ["side", "−", "Everything on one screen: the factories left, both boards beside them"],
      ["stack", "+", "The classic table: big boards below the factories"],
    ].map(([mode, label, title]) => {
      const b = node("button", "flag", label);
      b.type = "button";
      b.dataset.boards = mode;
      b.title = title;
      b.addEventListener("click", () => {
        setBoardsMode(mode);
        sync();
        if (options.onChange) options.onChange(speed());
      });
      sizes.appendChild(b);
      return b;
    });
    panel.append(sizes);
  }

  host.append(head, panel);

  function sync() {
    const now = speed();
    buttons.forEach((b) => {
      b.setAttribute("aria-pressed", String(Number(b.dataset.speed) === now));
    });
    flagRows.forEach(({ pair, get, dataKey }) => {
      pair.forEach((b) => {
        b.setAttribute("aria-pressed", String((b.dataset[dataKey] === "true") === get()));
      });
    });
    boardButtons.forEach((b) => {
      b.setAttribute("aria-pressed", String(b.dataset.boards === boardsMode()));
    });
    const bits = [now ? "animation " + LABELS[now] : "animation off"];
    if (options.popups) bits.push(popupsOn() ? "pop-ups on" : "pop-ups off");
    if (options.confirm) bits.push(confirmOn() ? "confirm on" : "confirm off");
    if (options.boards) bits.push(boardsMode() === "stack" ? "boards +" : "boards −");
    summary.textContent = bits.join(" · ");
    // one sentence whatever the OS motion preference: this switch decides
    // either way (see animate.js), and saying so here read as a lecture
    hint.textContent =
      "Tiles always travel to where they land. Slow it down to follow a long turn, " +
      "or turn it off for instant play.";
  }

  gear.addEventListener("click", () => {
    const opening = panel.hidden;
    panel.hidden = !opening;
    host.classList.toggle("open", opening);
    gear.setAttribute("aria-expanded", String(opening));
  });

  initSpeed();
  sync();

  // `panel` is handed back so a page can seat its own controls among these —
  // the player page moves its "AI thinks for" clock in here
  return { el: host, sync, open: () => gear.click(), panel };
}