/** Helpers for Zotero ItemPane collapsible sections. */

import { config } from "../../../package.json";
import { getLocaleID, getString } from "../../utils/locale";
import type { FluentMessageId } from "../../../typings/i10n";
import { getPref, setPref } from "../../utils/prefs";
import { openChatPaneWindow, openLecturePaneWindow } from "./itemPaneWindow";

export type ItemPaneKind = "chat" | "lecture";

const ADAPTIVE_PREF: Record<ItemPaneKind, keyof _ZoteroTypes.Prefs["PluginPrefsMap"]> =
  {
    chat: "chatPaneAdaptiveHeight",
    lecture: "lecturePaneAdaptiveHeight",
  };

const FIXED_HEIGHT: Record<ItemPaneKind, number> = {
  chat: 360,
  lecture: 420,
};

/** Lucide-derived toolbar icons (see addon/content/icons/pane-*.svg). */
function paneIconURL(file: string): string {
  return `chrome://${config.addonRef}/content/icons/${file}`;
}

const OPEN_WINDOW_ICON = paneIconURL("pane-open-window.svg");
const ADAPTIVE_ICON = paneIconURL("pane-adaptive-height.svg");
const ADAPTIVE_ICON_OFF = paneIconURL("pane-adaptive-height-fixed.svg");

export function prepareItemPaneBody(body: HTMLElement): void {
  body.classList.add("chatpapers-pane-body");
  body.style.minHeight = "0";
}

export function isAdaptiveHeight(kind: ItemPaneKind): boolean {
  const val = getPref(ADAPTIVE_PREF[kind]);
  return val !== false;
}

function sectionButtonTooltip(messageId: FluentMessageId): string {
  const fromBranch = getString(messageId, { branch: "tooltiptext" });
  const l10nId = getLocaleID(messageId);
  if (fromBranch && fromBranch !== l10nId) return fromBranch;
  return getString(messageId);
}

function applySectionButtonTooltip(
  btn: HTMLElement,
  messageId: FluentMessageId,
): void {
  const l10nId = getLocaleID(messageId);
  const tooltip = sectionButtonTooltip(messageId);
  btn.setAttribute("data-l10n-id", l10nId);
  btn.setAttribute("title", tooltip);
  btn.setAttribute("tooltiptext", tooltip);
  try {
    btn.ownerDocument?.l10n?.setAttributes?.(btn, l10nId);
  } catch {
    // ignore if Fluent is not ready on this document yet
  }
}

function styleSectionButtonIcon(btn: HTMLElement, icon: string): void {
  const url = `url('${icon}')`;
  btn.style.setProperty("--custom-button-icon-light", url);
  btn.style.setProperty("--custom-button-icon-dark", url);
  btn.style.setProperty("list-style-image", url);
  btn.style.setProperty("-moz-context-properties", "fill, fill-opacity");
  btn.style.setProperty("fill", "currentColor");
}

function findSectionButton(
  section: HTMLElement | null,
  type: string,
): HTMLElement | null {
  if (!section) return null;
  return (section.querySelector(`.${type}.section-custom-button`) ??
    section.querySelector(`.${type}`)) as HTMLElement | null;
}

function applyOpenInWindowButtonIcon(body: HTMLElement): boolean {
  const section = resolveCollapsibleSection(body);
  const btn = findSectionButton(section, "open-in-window");
  if (!btn) return false;
  styleSectionButtonIcon(btn, OPEN_WINDOW_ICON);
  applySectionButtonTooltip(btn, "item-pane-open-window");
  return true;
}

export function updateAdaptiveButtonState(
  body: HTMLElement,
  adaptive: boolean,
): boolean {
  const section = resolveCollapsibleSection(body);
  const btn = findSectionButton(section, "adaptive-height");
  if (!btn) return false;
  btn.setAttribute("aria-pressed", adaptive ? "true" : "false");
  btn.classList.toggle("chatpapers-adaptive-active", adaptive);
  styleSectionButtonIcon(btn, adaptive ? ADAPTIVE_ICON : ADAPTIVE_ICON_OFF);
  applySectionButtonTooltip(
    btn,
    adaptive ? "item-pane-adaptive-height-on" : "item-pane-adaptive-height-off",
  );
  return true;
}

export function applyItemPaneSectionButtonIcons(
  body: HTMLElement,
  adaptive = isAdaptiveHeight(
    (body.dataset.chatpapersPaneKind || "chat") as ItemPaneKind,
  ),
  attempt = 0,
): void {
  const openReady = applyOpenInWindowButtonIcon(body);
  const adaptiveReady = updateAdaptiveButtonState(body, adaptive);
  if ((openReady && adaptiveReady) || attempt >= 8) return;

  const win = body.ownerDocument?.defaultView;
  if (!win) return;
  win.requestAnimationFrame(() => {
    applyItemPaneSectionButtonIcons(body, adaptive, attempt + 1);
  });
}

export function applyAdaptiveHeight(
  body: HTMLElement,
  kind: ItemPaneKind,
  adaptive = isAdaptiveHeight(kind),
): void {
  body.classList.toggle("chatpapers-pane-adaptive", adaptive);
  body.classList.toggle("chatpapers-pane-fixed", !adaptive);
  body.dataset.chatpapersPaneKind = kind;

  const section = resolveCollapsibleSection(body);
  section?.classList.toggle("chatpapers-adaptive-height", adaptive);
  section?.classList.toggle("chatpapers-fixed-height", !adaptive);
  applyItemPaneSectionButtonIcons(body, adaptive);
}

export function toggleAdaptiveHeight(
  body: HTMLElement,
  kind: ItemPaneKind,
): boolean {
  const next = !isAdaptiveHeight(kind);
  setPref(ADAPTIVE_PREF[kind], next);
  applyAdaptiveHeight(body, kind, next);
  refreshSectionOpenHeight(body);
  return next;
}

export function refreshSectionOpenHeight(body: HTMLElement): void {
  const section = resolveCollapsibleSection(body);
  if (!section?.hasAttribute("open")) return;

  if (section.classList.contains("chatpapers-adaptive-height")) {
    section.style.setProperty("--open-height", "auto");
    body.style.removeProperty("max-height");
    body.style.removeProperty("overflow");
    return;
  }

  const kind = (body.dataset.chatpapersPaneKind || "chat") as ItemPaneKind;
  const maxH = FIXED_HEIGHT[kind] ?? 360;
  body.style.maxHeight = `${maxH}px`;
  body.style.overflowY = "auto";
  section.style.setProperty("--open-height", `${maxH}px`);
}

export function onItemPaneSectionToggle(options: {
  body: HTMLElement;
  event?: Event;
}): void {
  const section = resolveCollapsibleSection(options.body, options.event);
  if (!section) return;

  const open = section.hasAttribute("open");
  const adaptive = section.classList.contains("chatpapers-adaptive-height");

  if (open) {
    options.body.style.removeProperty("height");
    options.body.style.minHeight = "0";

    if (adaptive) {
      options.body.style.removeProperty("overflow");
      options.body.style.removeProperty("max-height");
      section.style.setProperty("--open-height", "auto");
      return;
    }

    options.body.style.overflowY = "auto";
    const kind = (options.body.dataset.chatpapersPaneKind || "chat") as ItemPaneKind;
    const maxH = FIXED_HEIGHT[kind] ?? 360;
    options.body.style.maxHeight = `${maxH}px`;
    section.style.setProperty("--open-height", `${maxH}px`);
    return;
  }

  options.body.style.minHeight = "0";
  options.body.style.height = "0";
  options.body.style.overflow = "hidden";
  options.body.style.removeProperty("max-height");
  section.style.setProperty("--open-height", "0px");
}

export function buildItemPaneSectionButtons(kind: ItemPaneKind) {
  return [
    {
      type: "open-in-window",
      icon: OPEN_WINDOW_ICON,
      l10nID: getLocaleID("item-pane-open-window"),
      onClick: ({ item }: { item?: Zotero.Item }) => {
        if (!item) return;
        if (kind === "chat") openChatPaneWindow(item);
        else openLecturePaneWindow(item);
      },
    },
    {
      type: "adaptive-height",
      icon: ADAPTIVE_ICON,
      l10nID: getLocaleID("item-pane-adaptive-height"),
      onClick: ({ body }: { body: HTMLElement }) => {
        toggleAdaptiveHeight(body, kind);
      },
    },
  ];
}

export function isItemPaneSectionBody(body: HTMLElement): boolean {
  return Boolean(body.closest("collapsible-section"));
}

export type SectionSummaryUpdater = (summary: string) => void;

export function clearSectionSummary(
  body: HTMLElement,
  updater?: SectionSummaryUpdater,
): void {
  updater?.("");
  const section = body.closest("collapsible-section");
  if (section) section.setAttribute("summary", "");
}

const SECTION_HEAD_MESSAGE: Record<ItemPaneKind, FluentMessageId> = {
  chat: "item-section-chat-head",
  lecture: "item-section-lecture-head",
};

/** Ensure native section head shows plugin name (not just the icon). */
export function applyItemPaneSectionHeadLabel(
  body: HTMLElement,
  kind: ItemPaneKind,
): void {
  const section = body.closest("collapsible-section") as HTMLElement | null;
  if (!section) return;

  const messageId = SECTION_HEAD_MESSAGE[kind];
  const l10nId = getLocaleID(messageId);
  section.dataset.l10nId = l10nId;

  const label = getString(messageId, "label");
  if (label && label !== l10nId) {
    section.setAttribute("label", label);
    return;
  }

  try {
    body.ownerDocument?.l10n?.setAttributes?.(section, l10nId);
  } catch {
    // Fluent may not be ready yet; label stays empty until next render hook.
  }
}

function resolveCollapsibleSection(
  body: HTMLElement,
  event?: Event,
): HTMLElement | null {
  const fromEvent = (event?.currentTarget ?? event?.target) as
    | HTMLElement
    | undefined;
  return (
    (fromEvent?.closest?.("collapsible-section") as HTMLElement | null) ??
    (body.closest("collapsible-section") as HTMLElement | null)
  );
}