const puppeteer = require('puppeteer');
const { JSDOM } = require('jsdom');

// const event_page = 'https://www.facebook.com/KulturVarsel/events';
const event_page = 'file:///home/zalox/src/kultar-events/index.html';
const upcoming_event_id = 'upcoming_events_card';
const upcoming_event_selector = `#${upcoming_event_id}`;


const month_name_to_number = (month_name) => {
  switch (month_name.toUpperCase()) {
  case "JAN": return 1;
  case "FEB": return 2;
  case "MAR": return 3;
  case "APR": return 4;
  case "MAY": return 5;
  case "JUN": return 6;
  case "JUL": return 7;
  case "AUG": return 8;
  case "SEP": return 9;
  case "OCT": return 10;
  case "NOV": return 10;
  case "DEC": return 12;
  }
}

const parse_event_date = (row) => {
  const date_column = row.firstChild.firstChild;
  const month_text = new String(date_column.firstChild.innerHTML);
  const day = new Number(date_column.lastChild.innerHTML);
  return {
    day: Number(day),
    month: Number(month_name_to_number(month_text)),
  };
}


const parse_event_name = (row) =>  {
  
}

const load_page = async () => {
  try {
    const browser = await puppeteer.launch();
    const page = await browser.newPage();

    await page.goto(event_page);
    await page.waitForSelector(upcoming_event_selector);

    let get_events = (upcoming_event_id) => {
      const upcoming_events_element = document.getElementById(upcoming_event_id);

      if (upcoming_events_element === null) {
        throw new Error(`Element ${upcoming_event_id} was not found.`);
      }

      if (upcoming_events_element.firstChild === null) {
        throw new Error(`Element ${upcoming_event_id} firstChild was not found.`);
      }

      if (upcoming_events_element.firstChild.children === null) {
        throw new Error(`Element ${upcoming_event_id} children not found.`);
      }

      return Array.from(upcoming_events_element.firstChild.children).map(item => item.innerHTML);
    };


    const events = await page.evaluate(get_events, upcoming_event_id);

    const htmlToTableRowElement = (table) => {
      const { document } = (new JSDOM(table)).window;
      return Array.from(document.body.getElementsByTagName('tr'))[0];
    }

    const emptyArrays = item => item;


    const parseRowToEvents = table_row => {
      const date = parse_event_date(table_row);
      const name = parse_event_name(table_row);
      return { date, name };
    };

    const parsed_events = events
          .map(htmlToTableRowElement)
          .filter(emptyArrays)
          .map(parseRowToEvents)
    ;
    


    console.log(parsed_events);
  }

  catch(e) {
    console.error(e);
  }
};

(
  async () => {
    await load_page();
    process.exit();
  }
)();