/** H5 富文本表格 DOM 操作 */

export function createEmptyCell(tagName = 'td') {
	const cell = document.createElement(tagName)
	cell.innerHTML = '<p><br></p>'
	return cell
}

export function buildTableHtml(rows = 3, cols = 3) {
	let html = '<table><tbody>'
	for (let r = 0; r < rows; r += 1) {
		html += '<tr>'
		for (let c = 0; c < cols; c += 1) {
			html += '<td><p><br></p></td>'
		}
		html += '</tr>'
	}
	html += '</tbody></table><p><br></p>'
	return html
}

export function getCurrentCell(editorEl) {
	const sel = window.getSelection()
	if (!sel || sel.rangeCount === 0) return null
	let node = sel.anchorNode
	if (node?.nodeType === Node.TEXT_NODE) node = node.parentElement
	const cell = node?.closest?.('td, th')
	if (!cell || !editorEl?.contains(cell)) return null
	return cell
}

export function addRowBefore(cell) {
	const row = cell.closest('tr')
	const newRow = row.cloneNode(true)
	newRow.querySelectorAll('td, th').forEach((item) => {
		item.innerHTML = '<p><br></p>'
		item.removeAttribute('colspan')
		item.removeAttribute('rowspan')
	})
	row.before(newRow)
	return newRow.cells[cell.cellIndex] || newRow.cells[0]
}

export function addRowAfter(cell) {
	const row = cell.closest('tr')
	const newRow = row.cloneNode(true)
	newRow.querySelectorAll('td, th').forEach((item) => {
		item.innerHTML = '<p><br></p>'
		item.removeAttribute('colspan')
		item.removeAttribute('rowspan')
	})
	row.after(newRow)
	return newRow.cells[cell.cellIndex] || newRow.cells[0]
}

export function deleteRow(cell) {
	const row = cell.closest('tr')
	const section = row?.parentElement
	if (!row || !section || section.querySelectorAll('tr').length <= 1) return null
	const focusCell =
		row.nextElementSibling?.cells[cell.cellIndex] ||
		row.previousElementSibling?.cells[cell.cellIndex] ||
		null
	row.remove()
	return focusCell
}

export function addColBefore(cell) {
	const index = cell.cellIndex
	const table = cell.closest('table')
	table.querySelectorAll('tr').forEach((row) => {
		const refCell = row.cells[index]
		if (!refCell) return
		refCell.before(createEmptyCell(refCell.tagName.toLowerCase()))
	})
	return cell.parentElement.cells[index]
}

export function addColAfter(cell) {
	const index = cell.cellIndex
	const table = cell.closest('table')
	table.querySelectorAll('tr').forEach((row) => {
		const refCell = row.cells[index]
		if (!refCell) return
		refCell.after(createEmptyCell(refCell.tagName.toLowerCase()))
	})
	return cell.parentElement.cells[index + 1]
}

export function deleteCol(cell) {
	const index = cell.cellIndex
	const table = cell.closest('table')
	if (cell.parentElement.cells.length <= 1) return null
	let focusCell = null
	table.querySelectorAll('tr').forEach((row) => {
		const target = row.cells[index]
		if (!target) return
		if (row === cell.parentElement) {
			focusCell = row.cells[index + 1] || row.cells[index - 1] || null
		}
		target.remove()
	})
	return focusCell
}

export function deleteTable(cell) {
	cell.closest('table')?.remove()
}