// Pure decision logic for the pack-wide browser-chrome features: the
// favicon/tab-title queue status, the live per-node status badges, and the
// per-node runtime badges.
//
// No DOM or LiteGraph access here — js/chrome/index.js owns the wiring.
// Everything exported is unit-tested in tests/chrome.test.mjs.

// Matches exactly the queue prefix composeTitle() writes: "(N) " with a
// single space. Anything else (mid-title parens, "(3)NoSpace") is treated
// as part of the page's real title and left alone.
const QUEUE_PREFIX = /^\(\d+\) /;

// Remove our own "(N) " queue prefix from a tab title, if present.
export function stripQueuePrefix(title) {
  if (typeof title !== "string") return "";
  return title.replace(QUEUE_PREFIX, "");
}

// Compose the tab title for a queue depth. Always strips any existing
// queue prefix first so repeated calls never stack "(2) (3) ..." — the
// input may be a title we already rewrote. N <= 0 (or junk) restores the
// bare title exactly.
export function composeTitle(title, queueRemaining) {
  const base = stripQueuePrefix(title);
  const n = Number(queueRemaining);
  if (!Number.isFinite(n) || n <= 0) return base;
  return `(${Math.floor(n)}) ${base}`;
}

// Format a node runtime in seconds for a badge: "49ms", "1.50s", "1m35s".
// ASCII only. Junk and negatives format to "" so callers can skip drawing.
export function formatDuration(seconds) {
  const s = Number(seconds);
  if (!Number.isFinite(s) || s < 0) return "";
  const ms = Math.round(s * 1000);
  if (ms < 1000) return `${ms}ms`;
  if (ms < 60000) {
    const fixed = (ms / 1000).toFixed(2);
    // 59.999s rounds up to "60.00" — carry it into the minutes form.
    if (fixed !== "60.00") return `${fixed}s`;
  }
  const totalSeconds = Math.round(ms / 1000);
  const minutes = Math.floor(totalSeconds / 60);
  return `${minutes}m${totalSeconds - minutes * 60}s`;
}

// Fresh per-run accumulator. `totals` maps node id (string) -> seconds.
export function createRunState() {
  return { runningId: null, startedAt: 0, totals: new Map() };
}

// State transition for one "executing" event. Closes out the elapsed time
// of the previously-running node (accumulating, so a node revisited by a
// batched loop sums across visits) and stamps the new node's start time.
// `nodeId` is the newly-executing node id, or null when the run finished.
// Returns the closed-out totals as [{ id, seconds }] so the caller can
// stamp them onto graph nodes; calling again with null while idle is a
// no-op. A clock that goes backwards contributes zero, never negative.
export function advanceExecution(state, nodeId, now) {
  const timestamp = Number(now) || 0;
  const updates = [];
  if (state.runningId !== null) {
    const elapsed = Math.max(0, (timestamp - state.startedAt) / 1000);
    const seconds = (state.totals.get(state.runningId) ?? 0) + elapsed;
    state.totals.set(state.runningId, seconds);
    updates.push({ id: state.runningId, seconds });
  }
  state.runningId = nodeId == null ? null : String(nodeId);
  state.startedAt = timestamp;
  return updates;
}

// Fresh live-status store. `entries` maps node id (string) -> { text,
// progress }, where progress is 0..1 or null when the node reports none.
export function createStatusState() {
  return { entries: new Map() };
}

const STATUS_MAX_LENGTH = 24;

// Badge text is drawn on the canvas: one ASCII line, length-capped. The
// backend sends str() of whatever the node passed, so junk is expected.
function badgeText(text) {
  if (typeof text !== "string") return "";
  return text
    .replace(/[^\x20-\x7e]+/g, " ")
    .replace(/\s+/g, " ")
    .trim()
    .slice(0, STATUS_MAX_LENGTH);
}

// 0..1, or null for "this node reports no fraction" — which the backend
// sends as null, and Number(null) would otherwise read as a 0% bar.
function badgeProgress(progress) {
  if (progress === null || progress === undefined || progress === "") return null;
  const value = Number(progress);
  if (!Number.isFinite(value)) return null;
  return Math.min(1, Math.max(0, value));
}

// Fold one "ausboss-node-status" payload into the state. Returns the node id
// whose badge changed, or null when the payload says nothing usable. Empty
// text retracts that node's badge, so a node can clear itself mid-run.
export function applyStatus(state, detail) {
  const id = detail?.node_id;
  if (id === undefined || id === null || id === "") return null;
  const key = String(id);
  const text = badgeText(detail.text);
  if (!text) return state.entries.delete(key) ? key : null;
  state.entries.set(key, { text, progress: badgeProgress(detail.progress) });
  return key;
}

// Retire live statuses, keeping `keepId`'s entry when one is passed — that
// is the node still executing. Returns the cleared ids so the caller can
// clear their badges.
export function clearStatuses(state, keepId) {
  const keep = keepId == null ? null : String(keepId);
  const cleared = [];
  for (const id of state.entries.keys()) {
    if (id !== keep) cleared.push(id);
  }
  for (const id of cleared) state.entries.delete(id);
  return cleared;
}

// Which badge a node draws. A live status always wins — it is transient and
// describes right now — and the post-run runtime badge fills in once the
// status is retired. Returns { kind, text, progress } or null for nothing.
export function badgeFor(status, seconds) {
  const text = badgeText(status?.text);
  if (text) return { kind: "live", text, progress: badgeProgress(status?.progress) };
  if (typeof seconds !== "number") return null;
  const duration = formatDuration(seconds);
  return duration ? { kind: "runtime", text: duration, progress: null } : null;
}