<?php

namespace TablePress\PhpOffice\PhpSpreadsheet\Worksheet;

use TablePress\PhpOffice\PhpSpreadsheet\Cell\Cell;
use TablePress\PhpOffice\PhpSpreadsheet\Cell\Coordinate;
use TablePress\PhpOffice\PhpSpreadsheet\Exception as PhpSpreadsheetException;

/**
 * @extends CellIterator<string>
 */
class RowCellIterator extends CellIterator
{
	/**
	 * Current iterator position.
	 *
	 * @var int
	 */
	private $currentColumnIndex;

	/**
	 * Row index.
	 *
	 * @var int
	 */
	private $rowIndex = 1;

	/**
	 * Start position.
	 *
	 * @var int
	 */
	private $startColumnIndex = 1;

	/**
	 * End position.
	 *
	 * @var int
	 */
	private $endColumnIndex = 1;

	/**
	 * Create a new column iterator.
	 *
	 * @param Worksheet $worksheet The worksheet to iterate over
	 * @param int $rowIndex The row that we want to iterate
	 * @param string $startColumn The column address at which to start iterating
	 * @param string $endColumn Optionally, the column address at which to stop iterating
	 */
	public function __construct(Worksheet $worksheet, $rowIndex = 1, $startColumn = 'A', $endColumn = null)
	{
		// Set subject and row index
		$this->worksheet = $worksheet;
		$this->cellCollection = $worksheet->getCellCollection();
		$this->rowIndex = $rowIndex;
		$this->resetEnd($endColumn);
		$this->resetStart($startColumn);
	}

	/**
	 * (Re)Set the start column and the current column pointer.
	 *
	 * @param string $startColumn The column address at which to start iterating
	 *
	 * @return $this
	 */
	public function resetStart(string $startColumn = 'A')
	{
		$this->startColumnIndex = Coordinate::columnIndexFromString($startColumn);
		$this->adjustForExistingOnlyRange();
		$this->seek(Coordinate::stringFromColumnIndex($this->startColumnIndex));

		return $this;
	}

	/**
	 * (Re)Set the end column.
	 *
	 * @param string $endColumn The column address at which to stop iterating
	 *
	 * @return $this
	 */
	public function resetEnd($endColumn = null)
	{
		$endColumn = $endColumn ?: $this->worksheet->getHighestColumn();
		$this->endColumnIndex = Coordinate::columnIndexFromString($endColumn);
		$this->adjustForExistingOnlyRange();

		return $this;
	}

	/**
	 * Set the column pointer to the selected column.
	 *
	 * @param string $column The column address to set the current pointer at
	 *
	 * @return $this
	 */
	public function seek(string $column = 'A')
	{
		$columnId = Coordinate::columnIndexFromString($column);
		if ($this->onlyExistingCells && !($this->cellCollection->has($column . $this->rowIndex))) {
			throw new PhpSpreadsheetException('In "IterateOnlyExistingCells" mode and Cell does not exist');
		}
		if (($columnId < $this->startColumnIndex) || ($columnId > $this->endColumnIndex)) {
			throw new PhpSpreadsheetException("Column $column is out of range ({$this->startColumnIndex} - {$this->endColumnIndex})");
		}
		$this->currentColumnIndex = $columnId;

		return $this;
	}

	/**
	 * Rewind the iterator to the starting column.
	 */
	public function rewind(): void
	{
		$this->currentColumnIndex = $this->startColumnIndex;
	}

	/**
	 * Return the current cell in this worksheet row.
	 */
	public function current(): ?Cell
	{
		$cellAddress = Coordinate::stringFromColumnIndex($this->currentColumnIndex) . $this->rowIndex;

		return $this->cellCollection->has($cellAddress)
			? $this->cellCollection->get($cellAddress)
			: $this->worksheet->createNewCell($cellAddress);
	}

	/**
	 * Return the current iterator key.
	 */
	public function key(): string
	{
		return Coordinate::stringFromColumnIndex($this->currentColumnIndex);
	}

	/**
	 * Set the iterator to its next value.
	 */
	public function next(): void
	{
		do {
			++$this->currentColumnIndex;
		} while (($this->onlyExistingCells) && (!$this->cellCollection->has(Coordinate::stringFromColumnIndex($this->currentColumnIndex) . $this->rowIndex)) && ($this->currentColumnIndex <= $this->endColumnIndex));
	}

	/**
	 * Set the iterator to its previous value.
	 */
	public function prev(): void
	{
		do {
			--$this->currentColumnIndex;
		} while (($this->onlyExistingCells) && (!$this->cellCollection->has(Coordinate::stringFromColumnIndex($this->currentColumnIndex) . $this->rowIndex)) && ($this->currentColumnIndex >= $this->startColumnIndex));
	}

	/**
	 * Indicate if more columns exist in the worksheet range of columns that we're iterating.
	 */
	public function valid(): bool
	{
		return $this->currentColumnIndex <= $this->endColumnIndex && $this->currentColumnIndex >= $this->startColumnIndex;
	}

	/**
	 * Return the current iterator position.
	 */
	public function getCurrentColumnIndex(): int
	{
		return $this->currentColumnIndex;
	}

	/**
	 * Validate start/end values for "IterateOnlyExistingCells" mode, and adjust if necessary.
	 */
	protected function adjustForExistingOnlyRange(): void
	{
		if ($this->onlyExistingCells) {
			while ((!$this->cellCollection->has(Coordinate::stringFromColumnIndex($this->startColumnIndex) . $this->rowIndex)) && ($this->startColumnIndex <= $this->endColumnIndex)) {
				++$this->startColumnIndex;
			}
			while ((!$this->cellCollection->has(Coordinate::stringFromColumnIndex($this->endColumnIndex) . $this->rowIndex)) && ($this->endColumnIndex >= $this->startColumnIndex)) {
				--$this->endColumnIndex;
			}
		}
	}
}
