import { ITerminalAddon, Terminal } from 'xterm';
import { ISearchOptions, SearchAddon } from 'xterm-addon-search';
import './index.css';

export interface SearchBarOption extends ISearchOptions {
  searchAddon: SearchAddon;
}

const ADDON_MARKER_NAME = 'xterm-search-bar__addon';

export class SearchBarAddon implements ITerminalAddon {
  private readonly options: Partial<SearchBarOption>;
  private terminal: Terminal;
  private readonly searchAddon: SearchAddon;
  private searchBarElement: HTMLDivElement;
  private searchKey: string;

  constructor(options: Partial<SearchBarOption>) {
    this.options = options || {};
    if (this.options && this.options.searchAddon) {
      this.searchAddon = this.options.searchAddon;
    }
  }

  activate(terminal: Terminal): void {
    this.terminal = terminal;
    if (!this.searchAddon) {
      console.error('Cannot use search bar addon until search addon has been loaded!');
    }
  }

  dispose() {
    this.hidden();
  }

  /**
   *  Show the bar in the term
   * @returns empty
   * @memberof SearchBarAddon  necessary search addon instance
   */
  show() {
    if (!this.terminal || !this.terminal.element) {
      return;
    }
    if (this.searchBarElement) {
      this.searchBarElement.style.visibility = 'visible';
      (this.searchBarElement.querySelector('input') as HTMLInputElement).select();
      return;
    }

    this.terminal.element.style.position = 'relative';
    const element = document.createElement('div');
    element.innerHTML = `
       <input type="text" class="search-bar__input" name="search-bar__input"/>
       <button class="search-bar__btn prev"></button>
       <button class="search-bar__btn next"></button>
       <button class="search-bar__btn close"></button>
    `;
    element.className = ADDON_MARKER_NAME;
    const parentElement = <HTMLElement>this.terminal.element.parentElement;
    this.searchBarElement = element;
    if (!['relative', 'absoulte', 'fixed'].includes(parentElement.style.position)) {
      parentElement.style.position = 'relative';
    }
    parentElement.appendChild(this.searchBarElement);
    this.on('.search-bar__btn.close', 'click', () => {
      this.hidden();
    });
    this.on('.search-bar__btn.next', 'click', () => {
      this.searchAddon.findNext(this.searchKey, {
        incremental: false
      });
    });
    this.on('.search-bar__btn.prev', 'click', () => {
      this.searchAddon.findPrevious(this.searchKey, {
        incremental: false
      });
    });
    this.on('.search-bar__input', 'keyup', (e: any) => {
      this.searchKey = (e.target as HTMLInputElement).value;
      this.searchAddon.findNext(this.searchKey, {
        incremental: e.key !== `Enter`
      });
    });
    (this.searchBarElement.querySelector('input') as HTMLInputElement).select();
  }

  /**
   * You can manually call close, also can click the close button on the bar
   * @memberof SearchBarAddon
   */
  hidden() {
    if (this.searchBarElement && (this.terminal.element as HTMLElement).parentElement) {
      this.searchBarElement.style.visibility = 'hidden';
    }
  }

  private on(selector: string, event: string, cb: (e: any) => void) {
    const parentElement = <HTMLElement>(this.terminal.element as HTMLElement).parentElement;
    parentElement.addEventListener(event, (e) => {
      let target = e.target;

      while (target !== document.querySelector(selector)) {
        if (target === parentElement) {
          target = null;
          break;
        }

        target = (target as HTMLElement).parentElement;
      }

      if (target === document.querySelector(selector)) {
        cb.call(this, e);
        e.stopPropagation();
      }
    });
  }

  /**
   * You can customize your own style, and then add CSS string template after search bar init
   * @param {string} newStyle
   * @memberof SearchBarAddon
   */
  addNewStyle(newStyle: string) {
    let styleElement = document.getElementById(ADDON_MARKER_NAME) as HTMLStyleElement;

    if (!styleElement) {
      styleElement = document.createElement('style');
      styleElement.type = 'text/css';
      styleElement.id = ADDON_MARKER_NAME;
      document.getElementsByTagName('head')[0].appendChild(styleElement);
    }

    styleElement.appendChild(document.createTextNode(newStyle));
  }
}