import { config } from "../../../../package.json";
import { getString } from "../../../utils/locale";
import { cacheReaderSelection, getCachedReaderSelectionPosition } from "../../pdf/selection";
import { highlightTextInPdf } from "../../pdf/readerSync";
import { getRegularItem, resolvePaperAttachment } from "../infrastructure/zotero/adapter";
import { paperIdFromCacheKey } from "../infrastructure/pdf/fileHash";
import { explainSelectionLecture } from "../application/explainSelectionLecture";
import {
  beginSelectionExplainSession,
  isSelectionExplainSessionActive,
  playSelectionExplainExclusive,
} from "../application/playSelectionExplain";
import { lectureEvents } from "../infrastructure/events";

function tryString(value: unknown): string {
  if (typeof value === "string") return value.trim();
  if (value == null) return "";
  return String(value).trim();
}

function itemFromReader(reader: any): Zotero.Item | undefined {
  const attachmentId = reader?.itemID ?? reader?._itemID;
  if (!attachmentId) return undefined;
  const attachment = Zotero.Items.get(attachmentId);
  if (!attachment) return undefined;
  return getRegularItem(attachment);
}

function showHeadline(text: string): void {
  try {
    const pw = new Zotero.ProgressWindow({ closeOnClick: true });
    pw.changeHeadline(text);
    pw.show();
    pw.startCloseTimer(4000);
  } catch {
    // ignore
  }
}

export async function runSelectionExplainFromReader(
  reader: any,
  selectedText: string,
): Promise<void> {
  const text = tryString(selectedText);
  if (!text) return;

  const item = itemFromReader(reader);
  if (!item) {
    showHeadline(getString("lecture-selection-no-item"));
    return;
  }

  cacheReaderSelection(text);
  const sessionId = beginSelectionExplainSession();
  showHeadline(getString("lecture-selection-explaining"));

  try {
    const ctx = await resolvePaperAttachment(item);
    const result = await explainSelectionLecture({
      item,
      selectedText: text,
      onProgress: (message) => showHeadline(message),
    });

    if (!isSelectionExplainSessionActive(sessionId)) return;

    await highlightTextInPdf(item, {
      text: result.original,
      page: result.page,
      position: getCachedReaderSelectionPosition(result.original),
    });

    lectureEvents.emit("lecture:selection_explain", {
      paperId: paperIdFromCacheKey(ctx.cacheKey),
      cacheKey: ctx.cacheKey,
      itemId: String(getRegularItem(item).id),
      result,
    });

    if (!isSelectionExplainSessionActive(sessionId)) return;

    await playSelectionExplainExclusive(result);
    showHeadline(getString("lecture-selection-done"));
  } catch (e) {
    const msg = e instanceof Error ? e.message : String(e);
    ztoolkit.log("[ChatPapers:Lecture] selection explain failed", e);
    showHeadline(msg);
  }
}

export function registerSelectionExplainPopup(): void {
  try {
    Zotero.Reader.registerEventListener(
      "renderTextSelectionPopup",
      (event: any) => {
        try {
          const { doc, params, append, reader } = event;
          const text =
            tryString(params?.annotation?.text) || tryString(params?.text);
          if (!text) return;
          cacheReaderSelection(text);

          const btn = doc.createElement("button");
          btn.type = "button";
          btn.className =
            "toolbar-button wide-button chatpapers-selection-explain-btn";
          btn.textContent = getString("lecture-explain-selection-short");
          btn.title = getString("lecture-explain-selection");
          btn.addEventListener("click", (ev: Event) => {
            ev.preventDefault();
            ev.stopPropagation();
            void runSelectionExplainFromReader(reader, text);
          }, { once: true });
          append(btn);
        } catch (e) {
          ztoolkit.log("[ChatPapers:Lecture] selection popup button failed", e);
        }
      },
      config.addonID,
    );
  } catch (e) {
    ztoolkit.log("[ChatPapers:Lecture] registerSelectionExplainPopup failed", e);
  }
}