/**
 * @implements Rule<FuncCall>
 */
final class SprintfFormatSpecifierRule implements Rule
{
    #[Override]
    public function getNodeType() : string
    {
        return FuncCall::class;
    }

    #[Override]
    public function processNode(Node $node, Scope $scope) : array
    {
        if ( ! $node->name instanceof Name) {
            return [];
        }

        $functionName = $node->name->toString();

        if ($functionName !== 'sprintf') {
            return [];
        }

        $args = $node->getArgs();

        if (count($args) < 1) {
            return [];
        }

        $formatStringType = $scope->getType($args[0]->value);

        $errors = [];

        foreach ($formatStringType->getConstantStrings() as $constantString) {
            $formatString = $constantString->getValue();

            $specifiers = $this->extractFormatSpecifiers($formatString);

            foreach ($specifiers as $index => $specifier) {
                $argIndex = $index + 1;

                if ( ! isset($args[$argIndex])) {
                    continue;
                }

                $argumentType = $scope->getType($args[$argIndex]->value);
                $error = $this->validateSpecifierAgainstType($specifier, $argumentType, $argIndex);

                if ($error !== null) {
                    $errors[] = $error;
                }
            }
        }

        return $errors;
    }

    /**
     * @return list<string>
     */
    private function extractFormatSpecifiers(string $formatString) : array
    {
        $specifiers = [];
        $matches = [];

        if (preg_match_all('/%(?:\d+\$)?(?:[+\- 0#]*|\'.)*(?:\d+|\*)?(?:\.(?:\d+|\*))?([bcdeEfFgGhHosuxX])/', $formatString, $matches) > 0) {
            $specifiers = $matches[1];
        }

        return $specifiers;
    }

    private function validateSpecifierAgainstType(string $specifier, Type $argumentType, int $argIndex) : ?IdentifierRuleError
    {
        switch ($specifier) {
            case 's':
                $stringType = new StringType();
                $stringableType = new ObjectType(Stringable::class);
                $validType = new UnionType([$stringType, $stringableType]);

                if ( ! $validType->isSuperTypeOf($argumentType)->yes()) {
                    return RuleErrorBuilder::message(
                        'sprintf() format specifier %' . $specifier . ' at position ' . $argIndex . ' expects string or Stringable, ' . $argumentType->describe(VerbosityLevel::typeOnly()) . ' given.',
                    )->identifier('ticketswap.sprintf.invalidFormatSpecifier')->build();
                }

                break;

            case 'd':
            case 'u':
            case 'c':
            case 'o':
            case 'x':
            case 'X':
            case 'b':
                $intType = new IntegerType();

                if ( ! $intType->isSuperTypeOf($argumentType)->yes()) {
                    return RuleErrorBuilder::message(
                        'sprintf() format specifier %' . $specifier . ' at position ' . $argIndex . ' expects int, ' . $argumentType->describe(VerbosityLevel::typeOnly()) . ' given.',
                    )->identifier('ticketswap.sprintf.invalidFormatSpecifier')->build();
                }

                break;

            case 'f':
            case 'F':
            case 'g':
            case 'G':
            case 'h':
            case 'H':
                $floatType = new FloatType();

                if ( ! $floatType->isSuperTypeOf($argumentType)->yes()) {
                    return RuleErrorBuilder::message(
                        'sprintf() format specifier %' . $specifier . ' at position ' . $argIndex . ' expects float, ' . $argumentType->describe(VerbosityLevel::typeOnly()) . ' given.',
                    )->identifier('ticketswap.sprintf.invalidFormatSpecifier')->build();
                }

                break;
        }

        return null;
    }
}