/**
 * 
 * This bookmarklet extracts event data from the first four tables on a webpage, 
 * specifically looking for tables that contain 'date', 'venue', and 'location' headers. 
 * It processes the event data to identify special events and formats the dates. 
 * The extracted data is then used to create an iCalendar (.ics) file, which is 
 * automatically downloaded to the user's device.
 * 
 * Functions:
 * - extractEventData: Extracts event data from the first four tables on the webpage.
 * - createICal: Creates an iCalendar (.ics) content string from the extracted event data.
 * - downloadICal: Initiates the download of the iCalendar (.ics) file with the given content and filename.
 */
javascript: (() => {
	function extractEventData() {
		let tables = document.querySelectorAll('table');
		if (tables.length > 4) {
			tables = Array.from(tables).slice(0, 4);
		}
		const data = [];

		tables.forEach(table => {
			const headers = [];
			const rows = table.querySelectorAll('tr');

			const firstRow = rows[0];
			firstRow.querySelectorAll('td').forEach(td => {
				headers.push(td.textContent.trim().toLowerCase());
			});

			if (
				headers.includes('date') &&
				headers.includes('venue') &&
				headers.includes('location')
			) {
				Array.from(rows)
					.slice(1)
					.forEach(row => {
						const cells = row.querySelectorAll('td');
						const rowData = {};

						if (
							Array.from(cells).some(cell =>
								cell.querySelector('span[style*="color: #2dc26b"]')
							)
						) {
							rowData.specialEvent = true;
						}
						cells.forEach((cell, j) => {
							const header = headers[j];
							let cellText = cell.innerHTML.replace(/<br\s*\/?>/gi, ', ').trim();
							cellText = cellText.replace(/<\/?[^>]+(>|$)/g, '').trim();

							if (header === 'date') {
								const month = cellText.split(' ')[0];
								const year = cellText.split(',')[1].trim();
								const startDay = cellText
									.split(' ')[1]
									.split(cellText.includes(' – ') ? ' – ' : '–')[0]
									.trim();
								const endDay = cellText
									.split(cellText.includes(' – ') ? ' – ' : '–')[1]
									.split(',')[0]
									.trim();
								rowData.startDate = `${month} ${startDay}, ${year}`;
								rowData.endDate = `${month} ${endDay}, ${year}`;
							} else if (header === 'venue') {
								rowData.venue = cellText;
							} else if (header === 'location') {
								rowData.location = cellText;
							}
						});

						data.push(rowData);
					});
			}
		});

		return data;
	}

	const data = extractEventData(tables);

  function createICal(events) {
    let icalContent =
      'BEGIN:VCALENDAR\nVERSION:2.0\nPRODID:-//FragginWagon//P!P //Regional-Special-Championships\n';

    events.forEach(event => {
      icalContent += 'BEGIN:VEVENT\n';
      icalContent += `DTSTART:${new Date(event.startDate).toISOString().replace(/[-:]/g, '').split('.')[0]}Z\n`;
      icalContent += `DTEND:${new Date(event.endDate).toISOString().replace(/[-:]/g, '').split('.')[0]}Z\n`;
      icalContent += `SUMMARY:${event.specialEvent ? 'Special Event' : 'Regional'} - ${event.venue} \n`;
      icalContent += `LOCATION:${event.location}\n`;
      icalContent += 'END:VEVENT\n';
    });

    icalContent += 'END:VCALENDAR';

    return icalContent;
  }

  function downloadICal(content, filename) {
    const blob = new Blob([content], { type: 'text/calendar' });
    const url = URL.createObjectURL(blob);
    const a = document.createElement('a');
    a.href = url;
    a.download = filename;
    document.body.appendChild(a);
    a.click();
    document.body.removeChild(a);
    URL.revokeObjectURL(url);
  }

	const newIcalContent = createICal(extractEventData());
  downloadICal(newIcalContent, 'play_pokemon_regional_special_events.ics');
})();