<?php declare(strict_types = 1);

namespace SlevomatCodingStandard\Sniffs\Namespaces;

use PHP_CodeSniffer\Files\File;
use PHP_CodeSniffer\Sniffs\Sniff;
use SlevomatCodingStandard\Helpers\NamespaceHelper;
use SlevomatCodingStandard\Helpers\TokenHelper;
use SlevomatCodingStandard\Helpers\UseStatement;
use SlevomatCodingStandard\Helpers\UseStatementHelper;
use function array_map;
use function count;
use function end;
use function explode;
use function implode;
use function min;
use function reset;
use function sprintf;
use function strcasecmp;
use function strcmp;
use function uasort;
use const T_OPEN_TAG;
use const T_SEMICOLON;

class AlphabeticallySortedUsesSniff implements Sniff
{

	public const CODE_INCORRECT_ORDER = 'IncorrectlyOrderedUses';

	/** @var bool */
	public $psr12Compatible = true;

	/** @var bool */
	public $caseSensitive = false;

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

	/**
	 * @phpcsSuppress SlevomatCodingStandard.Functions.UnusedParameter.UnusedParameter
	 * @phpcsSuppress SlevomatCodingStandard.TypeHints.ParameterTypeHint.MissingNativeTypeHint
	 * @param File $phpcsFile
	 * @param int $openTagPointer
	 */
	public function process(File $phpcsFile, $openTagPointer): void
	{
		if (TokenHelper::findPrevious($phpcsFile, T_OPEN_TAG, $openTagPointer - 1) !== null) {
			return;
		}

		$fileUseStatements = UseStatementHelper::getFileUseStatements($phpcsFile);
		foreach ($fileUseStatements as $useStatements) {
			$lastUse = null;
			foreach ($useStatements as $useStatement) {
				if ($lastUse === null) {
					$lastUse = $useStatement;
				} else {
					$order = $this->compareUseStatements($useStatement, $lastUse);
					if ($order < 0) {
						$fix = $phpcsFile->addFixableError(
							sprintf(
								'Use statements should be sorted alphabetically. The first wrong one is %s.',
								$useStatement->getFullyQualifiedTypeName()
							),
							$useStatement->getPointer(),
							self::CODE_INCORRECT_ORDER
						);
						if ($fix) {
							$this->fixAlphabeticalOrder($phpcsFile, $useStatements);
						}

						return;
					}

					$lastUse = $useStatement;
				}
			}
		}
	}

	/**
	 * @param File $phpcsFile
	 * @param UseStatement[] $useStatements
	 */
	private function fixAlphabeticalOrder(File $phpcsFile, array $useStatements): void
	{
		/** @var UseStatement $firstUseStatement */
		$firstUseStatement = reset($useStatements);
		/** @var UseStatement $lastUseStatement */
		$lastUseStatement = end($useStatements);
		$lastSemicolonPointer = TokenHelper::findNext($phpcsFile, T_SEMICOLON, $lastUseStatement->getPointer());
		$phpcsFile->fixer->beginChangeset();
		for ($i = $firstUseStatement->getPointer(); $i <= $lastSemicolonPointer; $i++) {
			$phpcsFile->fixer->replaceToken($i, '');
		}

		uasort($useStatements, function (UseStatement $a, UseStatement $b): int {
			return $this->compareUseStatements($a, $b);
		});

		$phpcsFile->fixer->addContent(
			$firstUseStatement->getPointer(),
			implode($phpcsFile->eolChar, array_map(static function (UseStatement $useStatement): string {
				$unqualifiedName = NamespaceHelper::getUnqualifiedNameFromFullyQualifiedName($useStatement->getFullyQualifiedTypeName());

				$useTypeName = UseStatement::getTypeName($useStatement->getType());
				$useTypeFormatted = $useTypeName !== null ? sprintf('%s ', $useTypeName) : '';

				if ($unqualifiedName === $useStatement->getNameAsReferencedInFile()) {
					return sprintf('use %s%s;', $useTypeFormatted, $useStatement->getFullyQualifiedTypeName());
				}

				return sprintf(
					'use %s%s as %s;',
					$useTypeFormatted,
					$useStatement->getFullyQualifiedTypeName(),
					$useStatement->getNameAsReferencedInFile()
				);
			}, $useStatements))
		);
		$phpcsFile->fixer->endChangeset();
	}

	private function compareUseStatements(UseStatement $a, UseStatement $b): int
	{
		if (!$a->hasSameType($b)) {
			$order = [
				UseStatement::TYPE_DEFAULT => 1,
				UseStatement::TYPE_FUNCTION => $this->psr12Compatible ? 2 : 3,
				UseStatement::TYPE_CONSTANT => $this->psr12Compatible ? 3 : 2,
			];

			return $order[$a->getType()] <=> $order[$b->getType()];
		}

		$aNameParts = explode(NamespaceHelper::NAMESPACE_SEPARATOR, $a->getFullyQualifiedTypeName());
		$bNameParts = explode(NamespaceHelper::NAMESPACE_SEPARATOR, $b->getFullyQualifiedTypeName());

		$minPartsCount = min(count($aNameParts), count($bNameParts));
		for ($i = 0; $i < $minPartsCount; $i++) {
			$comparison = $this->compare($aNameParts[$i], $bNameParts[$i]);
			if ($comparison === 0) {
				continue;
			}

			return $comparison;
		}

		return count($aNameParts) <=> count($bNameParts);
	}

	private function compare(string $a, string $b): int
	{
		if ($this->caseSensitive) {
			return strcmp($a, $b);
		}

		return strcasecmp($a, $b);
	}

}