<?php declare(strict_types = 1);

namespace SlevomatCodingStandard\Sniffs\Exceptions;

use Exception;
use PHP_CodeSniffer\Files\File;
use PHP_CodeSniffer\Sniffs\Sniff;
use SlevomatCodingStandard\Helpers\CatchHelper;
use SlevomatCodingStandard\Helpers\FixerHelper;
use SlevomatCodingStandard\Helpers\NamespaceHelper;
use SlevomatCodingStandard\Helpers\ReferencedNameHelper;
use SlevomatCodingStandard\Helpers\SuppressHelper;
use SlevomatCodingStandard\Helpers\TokenHelper;
use Throwable;
use function array_key_exists;
use function in_array;
use function sprintf;
use const T_BITWISE_OR;
use const T_CATCH;
use const T_EXTENDS;
use const T_FUNCTION;
use const T_INSTANCEOF;
use const T_NEW;
use const T_OPEN_PARENTHESIS;
use const T_OPEN_TAG;

class ReferenceThrowableOnlySniff implements Sniff
{

	public const CODE_REFERENCED_GENERAL_EXCEPTION = 'ReferencedGeneralException';

	private const NAME = 'SlevomatCodingStandard.Exceptions.ReferenceThrowableOnly';

	/**
	 * @return array<int, (int|string)>
	 */
	public function register(): array
	{
		return [
			T_OPEN_TAG,
		];
	}

	public function process(File $phpcsFile, int $openTagPointer): void
	{
		if (TokenHelper::findPrevious($phpcsFile, T_OPEN_TAG, $openTagPointer - 1) !== null) {
			return;
		}

		$tokens = $phpcsFile->getTokens();
		$message = sprintf('Referencing general \%s; use \%s instead.', Exception::class, Throwable::class);
		$referencedNames = ReferencedNameHelper::getAllReferencedNames($phpcsFile, $openTagPointer);
		foreach ($referencedNames as $referencedName) {
			$resolvedName = NamespaceHelper::resolveClassName(
				$phpcsFile,
				$referencedName->getNameAsReferencedInFile(),
				$referencedName->getStartPointer(),
			);
			if ($resolvedName !== '\\Exception') {
				continue;
			}
			$previousPointer = TokenHelper::findPreviousEffective($phpcsFile, $referencedName->getStartPointer() - 1);
			if (in_array($tokens[$previousPointer]['code'], [T_EXTENDS, T_NEW, T_INSTANCEOF], true)) {
				// Allow \Exception in extends and instantiating it
				continue;
			}
			if ($tokens[$previousPointer]['code'] === T_BITWISE_OR) {
				$previousPointer = TokenHelper::findPreviousExcluding(
					$phpcsFile,
					[...TokenHelper::INEFFECTIVE_TOKEN_CODES, ...TokenHelper::NAME_TOKEN_CODES, T_BITWISE_OR],
					$previousPointer - 1,
				);
			}
			if ($tokens[$previousPointer]['code'] === T_OPEN_PARENTHESIS) {
				/** @var int $openParenthesisOpenerPointer */
				$openParenthesisOpenerPointer = TokenHelper::findPreviousEffective($phpcsFile, $previousPointer - 1);
				if ($tokens[$openParenthesisOpenerPointer]['code'] === T_CATCH) {
					if ($this->searchForThrowableInNextCatches($phpcsFile, $openParenthesisOpenerPointer)) {
						continue;
					}
				} elseif (
					array_key_exists('parenthesis_owner', $tokens[$previousPointer])
					&& $tokens[$tokens[$previousPointer]['parenthesis_owner']]['code'] === T_FUNCTION
					&& $tokens[$previousPointer]['parenthesis_closer'] > $referencedName->getStartPointer()
					&& SuppressHelper::isSniffSuppressed(
						$phpcsFile,
						$openParenthesisOpenerPointer,
						sprintf('%s.%s', self::NAME, self::CODE_REFERENCED_GENERAL_EXCEPTION),
					)
				) {
					continue;
				}
			}

			$fix = $phpcsFile->addFixableError(
				$message,
				$referencedName->getStartPointer(),
				self::CODE_REFERENCED_GENERAL_EXCEPTION,
			);
			if (!$fix) {
				continue;
			}

			$phpcsFile->fixer->beginChangeset();

			FixerHelper::change($phpcsFile, $referencedName->getStartPointer(), $referencedName->getEndPointer(), '\Throwable');

			$phpcsFile->fixer->endChangeset();
		}
	}

	private function searchForThrowableInNextCatches(File $phpcsFile, int $catchPointer): bool
	{
		$tokens = $phpcsFile->getTokens();
		$nextCatchPointer = TokenHelper::findNextEffective($phpcsFile, $tokens[$catchPointer]['scope_closer'] + 1);

		while ($nextCatchPointer !== null) {
			$nextCatchToken = $tokens[$nextCatchPointer];
			if ($nextCatchToken['code'] !== T_CATCH) {
				break;
			}

			$caughtTypes = CatchHelper::findCaughtTypesInCatch($phpcsFile, $nextCatchToken);
			if (in_array('\\Throwable', $caughtTypes, true)) {
				return true;
			}

			$nextCatchPointer = TokenHelper::findNextEffective($phpcsFile, $nextCatchToken['scope_closer'] + 1);
		}

		return false;
	}

}
