// @ts-nocheck
/* global Dialog */
import { buildBoardContext, resolveToggleTarget } from '../../utils/boardUtils.js';
import { generateOpId } from '../../utils/uuid.js';

// Conditional base class — test environment lacks foundry globals.
// At module load time in tests, foundry is undefined → fallback class is used.

/** @private */
const _AppBase =
  typeof foundry !== 'undefined' &&
  foundry.applications?.api?.HandlebarsApplicationMixin &&
  foundry.applications?.api?.ApplicationV2
    ? foundry.applications.api.HandlebarsApplicationMixin(
        foundry.applications.api.ApplicationV2
      )
    : class _FallbackApp {
        static DEFAULT_OPTIONS = {};
        static PARTS = {};
        get rendered() { return this._rendered ?? false; }
        set rendered(v) { this._rendered = v; }
        get element() { return this._element ?? null; }
        async render() { this._rendered = true; }
        async close() { this._rendered = false; }
        async _prepareContext() { return {}; }
        _onRender() {}
        _onClose() {}
        _onPosition() {}
      };

/**
 * Floating GM-only Director's Board window.
 * Displays all connected participants as a seating-chart grid with per-participant
 * visibility toggle. Extends ApplicationV2 via HandlebarsApplicationMixin.
 */
export class DirectorsBoard extends _AppBase {
  static DEFAULT_OPTIONS = {
    id: 'scrying-pool-directors-board',
    classes: ['scrying-pool', 'directors-board'],
    window: { title: "Director's Board", resizable: true },
    position: { width: 400, height: 300 },
  };

  static PARTS = {
    board: {
      template: 'modules/video-view-manager/templates/directors-board.hbs',
    },
  };

  /**
   * @param {object} stateStore
   * @param {object} controller
   * @param {object} adapter
   * @param {object} [options]
   */
  constructor(stateStore, controller, adapter, options = {}) {
    super(options);
    this._stateStore = stateStore;
    this._controller = controller;
    this._adapter = adapter;
    this._hookId = null;
    /** @type {Map<string, string>|null} Pre-bulk-action snapshot for single-step undo */
    this._undoSnapshot = null;
    /** @type {Map<string, string>|null} Pre-spotlight snapshot for restore */
    this._spotlightSnapshot = null;
    /** @type {string|null} Currently keyboard-focused participant userId */
    this._focusedUserId = null;
    /** @type {Function|null} Click handler reference for cleanup */
    this._clickHandler = null;
    /** @type {Function|null} Focusin handler reference for cleanup */
    this._focusinHandler = null;
    /** @type {Function|null} Keydown handler reference for cleanup */
    this._keydownHandler = null;
    
    // Load saved position from user flags
    this._loadPosition();
  }

  /** Loads saved window position from GM user flag. */
  _loadPosition() {
    try {
      const saved = game.user?.getFlag('video-view-manager', 'directorsBoardState');
      if (saved?.open === true && saved.left != null && saved.top != null) {
        this.options.position = {
          left: saved.left,
          top: saved.top,
          width: saved.width ?? 400,
          height: saved.height ?? 300,
        };
      }
    } catch (err) {
      console.error('[ScryingPool] Failed to load directors board position:', err);
    }
  }

  /** Registers the stateChanged hook listener. Call once from module.js ready hook. */
  init() {
    this._hookId = Hooks.on('scrying-pool:stateChanged', (data) => this._onStateChanged(data));
  }

  /** Unregisters the stateChanged hook listener. */
  teardown() {
    if (this._hookId !== null) {
      Hooks.off('scrying-pool:stateChanged', this._hookId);
      this._hookId = null;
    }
  }

  /** Opens the board if closed; closes it if open (singleton toggle behaviour). */
  async toggle() {
    if (this.rendered) {
      await this.close();
    } else {
      await this.render({ force: true });
    }
  }

  /**
   * Sets all non-ghost participants to `active`. Stores pre-action snapshot for undo.
   * FR-12: ghost participants excluded.
   */
  showAll() {
    this._executeBulk('active');
  }

  /**
   * Sets all non-ghost participants to `hidden`. Stores pre-action snapshot for undo.
   * FR-12: ghost participants excluded.
   */
  hideAll() {
    this._executeBulk('hidden');
  }

  /**
   * Internal bulk-action executor for showAll/hideAll.
   * Captures a pre-action snapshot then dispatches per-participant actions.
   * Uses single getState call per user to avoid race conditions.
   * @param {'active'|'hidden'} targetState
   * @private
   */
  _executeBulk(targetState) {
    const users = this._adapter.users.all();
    
    // Get all user states in a single pass to avoid race conditions
    const userStates = new Map(users.map(u => [u.id, this._stateStore.getState(u.id)]));
    
    // Filter to non-ghost users and capture snapshot atomically
    const nonGhost = users.filter(u => userStates.get(u.id) !== 'ghost');
    
    // Capture pre-action snapshot (single-step undo) - use the states we already fetched
    this._undoSnapshot = new Map(nonGhost.map(u => [u.id, userStates.get(u.id)]));
    // Bulk supersedes spotlight restore
    this._spotlightSnapshot = null;

    for (const u of nonGhost) {
      if (this._controller.hasPendingOp?.(u.id)) continue;
      const opId = generateOpId();
      const baseRevision = this._controller.getRevision?.(u.id) ?? 0;
      this._controller.action('board', u.id, targetState, opId, baseRevision);
    }
    if (this.rendered) this.render({ force: true });
  }

  /**
   * Single-step undo: restores participants to their pre-bulk-action states.
   * No-op if no snapshot exists. Ghost participants are skipped.
   */
  undo() {
    if (!this._undoSnapshot) return;
    const snapshot = this._undoSnapshot;
    this._undoSnapshot = null;
    for (const [userId, targetState] of snapshot) {
      // Check current state to avoid restoring ghost users that have transitioned
      if (this._stateStore.getState(userId) === 'ghost') continue;
      if (this._controller.hasPendingOp?.(userId)) continue;
      const opId = generateOpId();
      const baseRevision = this._controller.getRevision?.(userId) ?? 0;
      this._controller.action('board', userId, targetState, opId, baseRevision);
    }
    if (this.rendered) this.render({ force: true });
  }

  /**
   * Spotlights a single participant: sets them `active`, all others `hidden`.
   * Captures a pre-spotlight snapshot and clears any undo snapshot.
   * Ghost participants are excluded from all operations.
   * @param {string} userId - The participant to spotlight
   */
  spotlight(userId) {
    // Guard: validate userId exists and is not null/undefined
    if (!userId) return;
    
    const users = this._adapter.users.all();
    
    // Get all user states in a single pass to avoid race conditions
    const userStates = new Map(users.map(u => [u.id, this._stateStore.getState(u.id)]));
    
    // Filter to non-ghost users
    const nonGhost = users.filter(u => userStates.get(u.id) !== 'ghost');
    
    // Check if the requested userId is valid (exists in non-ghost list)
    const validUserIds = new Set(nonGhost.map(u => u.id));
    if (!validUserIds.has(userId)) {
      console.warn(`[ScryingPool] spotlight: userId "${userId}" not found or is ghost`);
      return;
    }
    
    // Capture pre-spotlight snapshot for ALL users (including ghost for completeness)
    this._spotlightSnapshot = new Map(users.map(u => [u.id, userStates.get(u.id)]));
    this._undoSnapshot = null;

    for (const u of nonGhost) {
      if (this._controller.hasPendingOp?.(u.id)) continue;
      const targetState = u.id === userId ? 'active' : 'hidden';
      const opId = generateOpId();
      const baseRevision = this._controller.getRevision?.(u.id) ?? 0;
      this._controller.action('board', u.id, targetState, opId, baseRevision);
    }
    if (this.rendered) this.render({ force: true });
  }

  /**
   * Restores participants to their pre-spotlight states.
   * No-op if no spotlight snapshot exists. Ghost participants are skipped.
   */
  restoreSpotlight() {
    if (!this._spotlightSnapshot) return;
    const snapshot = this._spotlightSnapshot;
    this._spotlightSnapshot = null;
    for (const [userId, targetState] of snapshot) {
      // Check current state to avoid restoring ghost users that have transitioned
      if (this._stateStore.getState(userId) === 'ghost') continue;
      if (this._controller.hasPendingOp?.(userId)) continue;
      const opId = generateOpId();
      const baseRevision = this._controller.getRevision?.(userId) ?? 0;
      this._controller.action('board', userId, targetState, opId, baseRevision);
    }
    if (this.rendered) this.render({ force: true });
  }

  /**
   * Spotlights the currently focused participant (keyboard shortcut target).
   * No-op if no participant is focused.
   */
  spotlightFocused() {
    if (!this._focusedUserId) return;
    this.spotlight(this._focusedUserId);
  }

  /** @inheritdoc */
  async _prepareContext() {
    const base = buildBoardContext(this._stateStore, this._controller, this._adapter);
    return {
      ...base,
      hasUndo: this._undoSnapshot !== null,
      hasRestore: this._spotlightSnapshot !== null,
    };
  }

  /**
   * ApplicationV2 lifecycle — sets up event delegation on every render.
   * Removes old listeners first to prevent memory leaks.
   * @inheritdoc
   */
  _onRender(context, options) {
    super._onRender?.(context, options);
    const root = this.element;
    if (!root) return;
    
    // Remove old listeners if they exist (fixes memory leak and broken listeners after reopen)
    if (this._clickHandler) {
      root.removeEventListener('click', this._clickHandler);
    }
    if (this._focusinHandler) {
      root.removeEventListener('focusin', this._focusinHandler);
    }
    if (this._keydownHandler) {
      root.removeEventListener('keydown', this._keydownHandler);
    }
    
    // Create new bound handlers
    this._clickHandler = (e) => {
      const btn = e.target.closest('[data-action]');
      if (!btn) return;
      e.stopPropagation();
      switch (btn.dataset.action) {
        case 'toggle-participant': this._dispatchToggle(btn.dataset.userId); break;
        case 'show-all': this.showAll(); break;
        case 'hide-all': this.hideAll(); break;
        case 'undo': this.undo(); break;
        case 'restore-spotlight': this.restoreSpotlight(); break;
        case 'open-shortcut-panel': this._openShortcutPanel(); break;
      }
    };
    this._focusinHandler = (e) => {
      const card = e.target.closest('[data-user-id]');
      this._focusedUserId = card?.dataset?.userId ?? null;
    };
    this._keydownHandler = (e) => this._onKeydown(e);
    
    // Add new listeners
    root.addEventListener('click', this._clickHandler);
    root.addEventListener('focusin', this._focusinHandler);
    root.addEventListener('keydown', this._keydownHandler);
  }

  /**
   * Keyboard navigation within the participant grid.
   * ArrowLeft/Right/Up/Down move focus; Space/Enter toggles the focused card.
   * `?` opens the shortcut panel; Ctrl+Shift+P spotlights focused card.
   * @param {KeyboardEvent} e
   */
  _onKeydown(e) {
    const cards = [...(this.element?.querySelectorAll('[data-user-id]') ?? [])];
    if (cards.length === 0) return;
    const current = document.activeElement;
    const idx = cards.indexOf(current);
    
    // Guard against negative index (focus from non-card element)
    if (idx < 0) return;

    if (e.key === 'ArrowRight' || e.key === 'ArrowDown') {
      e.preventDefault();
      cards[(idx + 1) % cards.length]?.focus();
    } else if (e.key === 'ArrowLeft' || e.key === 'ArrowUp') {
      e.preventDefault();
      cards[(idx - 1 + cards.length) % cards.length]?.focus();
    } else if ((e.key === 'Enter' || e.key === ' ') && current?.dataset?.userId) {
      e.preventDefault();
      this._dispatchToggle(current.dataset.userId);
    } else if (e.key === '?') {
      e.preventDefault();
      this._openShortcutPanel();
    } else if (e.ctrlKey && e.shiftKey && e.code === 'KeyP') {
      e.preventDefault();
      this.spotlightFocused();
    }
  }

  /**
   * Dispatches a visibility toggle for a participant through the controller.
   * Matches FR-1: always goes through controller.action(), never direct setState.
   * @param {string} userId
   */
  _dispatchToggle(userId) {
    if (!userId) return;
    if (this._controller.hasPendingOp?.(userId)) return;
    const currentState = this._stateStore.getState(userId) ?? 'active';
    const targetState = resolveToggleTarget(currentState);
    const opId = generateOpId();
    const baseRevision = this._controller.getRevision?.(userId) ?? 0;
    this._controller.action('board', userId, targetState, opId, baseRevision);
  }

  /**
   * Hook handler — re-renders the board when a participant state changes.
   * @param {object} data
   */
  _onStateChanged(data) {
    // Suppress unused parameter warning - data is intentionally unused
    void data;
    if (this.rendered) {
      this.render({ force: true });
    }
  }

  /**
   * Opens a Dialog showing all Director's Board keyboard shortcuts and their current bindings.
   * Reads from game.keybindings.bindings when available, falling back to defaults.
   */
  _openShortcutPanel() {
    try {
      const localize = (key) => game.i18n?.localize(key) ?? key;

      const getBinding = (actionKey) => {
        // Check both namespaces due to migration from video-view-manager to scrying-pool
        const namespaces = ['scrying-pool', 'video-view-manager'];
        for (const ns of namespaces) {
          const bindings = game.keybindings?.bindings?.get(`${ns}.${actionKey}`);
          if (bindings?.[0]) {
            const b = bindings[0];
            const mods = (b.modifiers ?? []).join('+');
            return mods ? `${mods}+${b.key}` : b.key;
          }
        }
        return null;
      };

      const shortcuts = [
        { label: localize('video-view-manager.directorsBoard.shortcuts.openBoard'), binding: getBinding('openDirectorsBoard') ?? 'Ctrl+Shift+V' },
        { label: localize('video-view-manager.directorsBoard.shortcuts.showAll'), binding: getBinding('showAll') ?? 'Ctrl+Shift+S' },
        { label: localize('video-view-manager.directorsBoard.shortcuts.hideAll'), binding: getBinding('hideAll') ?? 'Ctrl+Shift+H' },
        { label: localize('video-view-manager.directorsBoard.shortcuts.spotlight'), binding: getBinding('spotlightParticipant') ?? 'Ctrl+Shift+P' },
      ];

      const rows = shortcuts.map(s => `<tr><td>${s.label}</td><td><kbd>${s.binding}</kbd></td></tr>`).join('');
      const content = `<table class="directors-board__shortcuts-table"><tbody>${rows}</tbody></table>`;

      if (typeof Dialog !== 'undefined') {
        new Dialog({
          title: localize('video-view-manager.directorsBoard.shortcuts.title'),
          content,
          buttons: { close: { label: 'Close' } },
          default: 'close',
        }).render(true);
      }
    } catch (err) {
      console.error('[ScryingPool] Failed to open shortcut panel:', err);
    }
  }

  /**
   * ApplicationV2 lifecycle — clean up event listeners when closed.
   * @inheritdoc
   */
  async _onClose(options) {
    await super._onClose?.(options);
    
    // Clean up event listeners to prevent memory leaks
    if (this._clickHandler) {
      this.element?.removeEventListener('click', this._clickHandler);
      this._clickHandler = null;
    }
    if (this._focusinHandler) {
      this.element?.removeEventListener('focusin', this._focusinHandler);
      this._focusinHandler = null;
    }
    if (this._keydownHandler) {
      this.element?.removeEventListener('keydown', this._keydownHandler);
      this._keydownHandler = null;
    }
    
    this._savePosition({ open: false });
  }

  /**
   * ApplicationV2 lifecycle — save window position when repositioned.
   * @inheritdoc
   */
  _onPosition(position) {
    super._onPosition?.(position);
    const { left, top, width, height } = position;
    this._savePosition({ left, top, width, height, open: true });
  }

  /**
   * Persists position/open state to GM user flag.
   * @private
   * @param {object} state
   */
  _savePosition(state) {
    try {
      game.user?.setFlag('video-view-manager', 'directorsBoardState', state);
    } catch (err) {
      console.error('[ScryingPool] Failed to save directors board position:', err);
    }
  }
}