/**
 * Employees Controller
 *
 * Handles content swap between list view and detail view,
 * plus tab switching within each view.
 * Uses History API for browser back/forward navigation.
 */

export class EmployeesController {
  private listView: HTMLElement | null = null;
  private detailView: HTMLElement | null = null;

  constructor() {
    this.listView = document.getElementById('employees-list-view');
    this.detailView = document.getElementById('employee-detail-view');

    // Only initialize if we're on the employees page
    if (!this.listView) return;

    this.setupListTabs();
    this.setupDetailTabs();
    this.setupChevronNavigation();
    this.setupBackNavigation();
    this.setupHistoryNavigation();
    this.restoreStateFromUrl();
  }

  /**
   * Setup popstate listener for browser back/forward
   */
  private setupHistoryNavigation(): void {
    window.addEventListener('popstate', (e: PopStateEvent) => {
      if (e.state?.employeeKey) {
        this.showDetailViewInternal(e.state.employeeKey);
      } else {
        this.showListViewInternal();
      }
    });
  }

  /**
   * Restore view state from URL on page load
   */
  private restoreStateFromUrl(): void {
    const hash = window.location.hash;
    if (hash.startsWith('#employee-')) {
      const employeeKey = hash.substring(1); // Remove #
      this.showDetailViewInternal(employeeKey);
    }
  }

  /**
   * Setup tab switching for the list view
   */
  private setupListTabs(): void {
    if (!this.listView) return;

    const tabs = this.listView.querySelectorAll<HTMLElement>('swp-tab-bar > swp-tab[data-tab]');

    tabs.forEach(tab => {
      tab.addEventListener('click', () => {
        const targetTab = tab.dataset.tab;
        if (targetTab) {
          this.switchTab(this.listView!, targetTab);
        }
      });
    });
  }

  /**
   * Setup tab switching for the detail view
   */
  private setupDetailTabs(): void {
    if (!this.detailView) return;

    const tabs = this.detailView.querySelectorAll<HTMLElement>('swp-tab-bar > swp-tab[data-tab]');

    tabs.forEach(tab => {
      tab.addEventListener('click', () => {
        const targetTab = tab.dataset.tab;
        if (targetTab) {
          this.switchTab(this.detailView!, targetTab);
        }
      });
    });
  }

  /**
   * Switch to a specific tab within a container
   */
  private switchTab(container: HTMLElement, targetTab: string): void {
    const tabs = container.querySelectorAll<HTMLElement>('swp-tab-bar > swp-tab[data-tab]');
    const contents = container.querySelectorAll<HTMLElement>('swp-tab-content[data-tab]');

    tabs.forEach(t => {
      t.classList.toggle('active', t.dataset.tab === targetTab);
    });

    contents.forEach(content => {
      content.classList.toggle('active', content.dataset.tab === targetTab);
    });
  }

  /**
   * Setup row click to show detail view
   * Ignores clicks on action buttons
   */
  private setupChevronNavigation(): void {
    document.addEventListener('click', (e: Event) => {
      const target = e.target as HTMLElement;

      // Ignore clicks on action buttons
      if (target.closest('swp-icon-btn') || target.closest('swp-table-actions')) {
        return;
      }

      const row = target.closest<HTMLElement>('swp-employee-row[data-employee-detail]');

      if (row) {
        const employeeKey = row.dataset.employeeDetail;
        if (employeeKey) {
          this.showDetailView(employeeKey);
        }
      }
    });
  }

  /**
   * Setup back button to return to list view
   */
  private setupBackNavigation(): void {
    document.addEventListener('click', (e: Event) => {
      const target = e.target as HTMLElement;
      const backLink = target.closest<HTMLElement>('[data-employee-back]');

      if (backLink) {
        this.showListView();
      }
    });
  }

  /**
   * Show the detail view and hide list view (with history push)
   */
  private showDetailView(employeeKey: string): void {
    // Push state to history
    history.pushState(
      { employeeKey },
      '',
      `#${employeeKey}`
    );
    this.showDetailViewInternal(employeeKey);
  }

  /**
   * Show detail view without modifying history (for popstate)
   */
  private showDetailViewInternal(employeeKey: string): void {
    if (this.listView && this.detailView) {
      this.listView.style.display = 'none';
      this.detailView.style.display = 'block';
      this.detailView.dataset.employee = employeeKey;

      // Reset to first tab
      this.switchTab(this.detailView, 'general');
    }
  }

  /**
   * Show the list view and hide detail view (with history push)
   */
  private showListView(): void {
    // Push state to history (clear hash)
    history.pushState(
      {},
      '',
      window.location.pathname
    );
    this.showListViewInternal();
  }

  /**
   * Show list view without modifying history (for popstate)
   */
  private showListViewInternal(): void {
    if (this.listView && this.detailView) {
      this.detailView.style.display = 'none';
      this.listView.style.display = 'block';
    }
  }
}