// Pure URL construction. No browser APIs, so node:test imports this directly.
//
// Every ChatGPT parameter below is undocumented by OpenAI and has broken before.
// This module's contract is only that it emits a well-formed URL; whether
// ChatGPT honours temporary-chat / hints is out of our control, which is
// why each is independently omittable and every label is hint-strength.
//
// The root path is mandatory: chatgpt.com/search began returning 404 in
// mid-2025, and the root form is what OpenAI's own extension uses.

const BASE = "https://chatgpt.com/";

export const MAX_URL_CHARS = 8000;

export function applyTemplate(template, query) {
  if (query === "") {
    return "";
  }
  const tpl = typeof template === "string" ? template : "";
  if (tpl.includes("{query}")) {
    // Replacer function, not a replacement string: String.prototype.replaceAll
    // gives $&, $`, $', and $$ special meaning in a replacement STRING, and
    // `query` is arbitrary page-selected text that can contain any of those
    // (shell one-liners routinely do). The function form disables that
    // interpretation entirely. Do not "simplify" this back to the string form.
    return tpl.replaceAll("{query}", () => query);
  }
  const trimmed = tpl.trim();
  return trimmed === "" ? query : `${trimmed} ${query}`;
}

function addOptionalParams(url, settings) {
  if (settings.temporaryChat) {
    url.searchParams.set("temporary-chat", "true");
  }
  if (settings.webSearch) {
    url.searchParams.set("hints", "search");
  }
  return url;
}

// Encode a complete prompt without silently shortening it; prepareAction owns
// the length budget and asks before shortening. q goes first, matching the
// most-cited working examples.
export function serializePrompt(settings, prompt) {
  const url = new URL(BASE);
  if (prompt) url.searchParams.set("q", prompt);
  return addOptionalParams(url, settings).href;
}