import { requireEl, warnOnce } from '../core/app-dom.js';
import { initPersistedDetailsGroup } from '../core/app-details-open-state.js';

export function initAsidePanels(options = {}) {
  const {
    barSelector = '.aside-icon-bar',
    panelSelector = '.app-sidebar-panel',
    titleSelector = '.app-sidebar-title',
    toolsSelector = '[data-aside-tools]',
    revealSidebarOnActivate = true,
    persistSidebarStateOnActivate = true
  } = options;

  const bar = requireEl(barSelector, { module: 'aside-panels' });
  if (!bar) {return;}

  const tabs = Array.from(bar.querySelectorAll('[data-aside-target]'));
  if (!tabs.length) {
    warnOnce('UI_EL_MISSING', 'No aside tabs found', { module: 'aside-panels' });
    return;
  }
  const shortcutItems = Array.from(bar.querySelectorAll('[data-aside-target], [data-aside-shortcut]'));

  const panels = Array.from(document.querySelectorAll(panelSelector));
  if (!panels.length) {
    warnOnce('UI_EL_MISSING', 'No aside panels found', { module: 'aside-panels' });
  }
  const titleEl = document.querySelector(titleSelector);
  const toolsHost = document.querySelector(toolsSelector);
  const sidebarController = window.AppSidebar || null;
  const defaultTitle = titleEl?.dataset.asideTitleDefault || titleEl?.textContent || '';
  const storageKey = bar.dataset.asideStorage || '';
  const isMac = /(Mac|iPhone|iPad|iPod)/i.test(navigator.platform || navigator.userAgent);
  const shortcutPrefix = isMac ? '⌘' : 'Ctrl+';

  const getPanelKey = (panel) => panel?.dataset?.asidePanel || '';
  const getTabKey = (tab) => tab?.dataset?.asideTarget || '';
  const getPanelTools = (panel) => panel?.querySelector('[data-aside-panel-tools]') || null;
  const getTabHref = (tab) => tab?.dataset?.asideHref || '';
  const isEditableTarget = (target) => {
    if (!target) {return false;}
    if (target.isContentEditable) {return true;}
    const tag = target.tagName;
    return tag === 'INPUT' || tag === 'TEXTAREA' || tag === 'SELECT';
  };

  const panelDetailsRegistry = new WeakMap();
  const findActiveDetailsKeys = (panel) => Array.from(panel.querySelectorAll('details[data-details-key]'))
    .filter((details) => details.querySelector('a.active, a[aria-current="page"]'))
    .map((details) => details.dataset.detailsKey || '')
    .filter(Boolean);

  const initPanelDetails = (panel) => {
    if (!panel) {return;}
    const existing = panelDetailsRegistry.get(panel);
    if (existing) {
      existing.apply();
      return;
    }

    const storageKey = panel.dataset.asideDetailsStorage || '';
    if (!storageKey) {return;}
    const openActive = panel.dataset.asideDetailsOpenActive === '1';
    const detailsState = initPersistedDetailsGroup({
      root: panel,
      storageKey,
      ensureOpenKeys: openActive ? () => findActiveDetailsKeys(panel) : []
    });

    if (!detailsState) {
      return;
    }

    panelDetailsRegistry.set(panel, detailsState);
  };

  const readStored = () => {
    if (!storageKey) {return null;}
    try {
      return window.localStorage.getItem(storageKey);
    } catch (error) {
      return null;
    }
  };

  const writeStored = (key) => {
    if (!storageKey) {return;}
    try {
      window.localStorage.setItem(storageKey, key);
    } catch (error) {
      // ignore storage errors
    }
  };

  const syncTools = (panel) => {
    if (!toolsHost) {return;}
    toolsHost.innerHTML = '';
    const tools = getPanelTools(panel);
    if (!tools) {return;}
    toolsHost.innerHTML = tools.innerHTML;
  };

  const openSidebar = (persist) => {
    if (!revealSidebarOnActivate || !sidebarController) {return;}
    if (typeof sidebarController.isHidden === 'function' && sidebarController.isHidden()) {
      sidebarController.show({ persist });
    }
    if (!sidebarController.isCollapsed()) {return;}
    sidebarController.open({ persist });
  };

  const setActive = (key, { fromUser = false } = {}) => {
    if (!key) {return;}

    let activePanel = null;
    panels.forEach((panel) => {
      const isActive = getPanelKey(panel) === key;
      if (isActive) {activePanel = panel;}
      panel.hidden = !isActive;
      panel.setAttribute('aria-hidden', isActive ? 'false' : 'true');
    });

    tabs.forEach((tab) => {
      const isActive = getTabKey(tab) === key;
      tab.classList.toggle('active', isActive);
      tab.setAttribute('aria-selected', isActive ? 'true' : 'false');
      tab.setAttribute('tabindex', isActive ? '0' : '-1');
    });

    if (titleEl) {
      const nextTitle = activePanel?.dataset?.asideTitle || defaultTitle;
      if (nextTitle) {
        titleEl.textContent = nextTitle;
      }
    }
    if (activePanel) {
      syncTools(activePanel);
      initPanelDetails(activePanel);
    }
    writeStored(key);
    if (fromUser) {
      openSidebar(persistSidebarStateOnActivate);
    }
  };

  const getInitialKey = () => {
    const stored = readStored();
    if (stored && panels.some((panel) => getPanelKey(panel) === stored)) {
      return stored;
    }
    const activeTab = tabs.find((tab) => tab.classList.contains('active'));
    if (activeTab) {return getTabKey(activeTab);}
    const visiblePanel = panels.find((panel) => !panel.hidden);
    if (visiblePanel) {return getPanelKey(visiblePanel);}
    return getTabKey(tabs[0]);
  };

  setActive(getInitialKey(), { fromUser: false });
  document.documentElement.classList.remove('aside-pending');
  window.AppAsidePanels = {
    setActive,
    open: (key) => setActive(key, { fromUser: true })
  };

  shortcutItems.forEach((item, idx) => {
    const base = item.dataset.tooltipBase || item.getAttribute('data-tooltip') || item.getAttribute('aria-label') || '';
    if (!base) {return;}
    const shortcutKey = idx === 9 ? '0' : String(idx + 1);
    item.dataset.tooltipBase = base;
    item.setAttribute('data-tooltip', `${base} (${shortcutPrefix}${shortcutKey})`);
  });

  tabs.forEach((tab) => {
    tab.addEventListener('click', (event) => {
      event.preventDefault();
      const key = getTabKey(tab);
      const isActive = tab.classList.contains('active');
      const href = getTabHref(tab);
      if (href) {
        const base = document.baseURI || window.location.origin;
        const targetUrl = new URL(href, base);
        const currentUrl = new URL(window.location.href);
        const isSame = targetUrl.pathname === currentUrl.pathname && targetUrl.search === currentUrl.search;
        if (!isSame) {
          setActive(key, { fromUser: true });
          window.location.href = targetUrl.toString();
          return;
        }
      }
      if (sidebarController && sidebarController.isCollapsed()) {
        sidebarController.open({ persist: persistSidebarStateOnActivate });
        setActive(key, { fromUser: true });
        return;
      }
      if (isActive && sidebarController) {
        if (sidebarController.isHidden?.()) {
          sidebarController.show({ persist: true });
        } else if (typeof sidebarController.hide === 'function') {
          sidebarController.hide({ persist: true });
        }
        return;
      }
      setActive(key, { fromUser: true });
    });
  });

  document.addEventListener('keydown', (event) => {
    if (!(event.metaKey || event.ctrlKey)) {return;}
    if (event.altKey) {return;}
    if (isEditableTarget(event.target)) {return;}
    const key = event.key;
    if (!/^[0-9]$/.test(key)) {return;}
    const index = key === '0' ? 9 : (Number.parseInt(key, 10) - 1);
    if (index < 0 || index >= shortcutItems.length) {return;}
    event.preventDefault();
    shortcutItems[index].click();
  });

}

if (document.readyState === 'loading') {
  document.addEventListener('DOMContentLoaded', () => initAsidePanels());
} else {
  initAsidePanels();
}