class ValidFunctionNameSniff

class ValidFunctionNameSniff extends AbstractScopeSniff {
    
    /**
     * A list of all PHP magic methods.
     *
     * @var array
     */
    protected $magicMethods = [
        'construct' => true,
        'destruct' => true,
        'call' => true,
        'callstatic' => true,
        'get' => true,
        'set' => true,
        'isset' => true,
        'unset' => true,
        'sleep' => true,
        'wakeup' => true,
        'serialize' => true,
        'unserialize' => true,
        'tostring' => true,
        'invoke' => true,
        'set_state' => true,
        'clone' => true,
        'debuginfo' => true,
    ];
    
    /**
     * A list of all PHP magic functions.
     *
     * @var array
     */
    protected $magicFunctions = [
        'autoload' => true,
    ];
    
    /**
     * Constructs a PEAR_Sniffs_NamingConventions_ValidFunctionNameSniff.
     */
    public function __construct() {
        parent::__construct(Tokens::$ooScopeTokens, [
            T_FUNCTION,
        ], true);
    }
    
    //end __construct()
    
    /**
     * Processes the tokens within the scope.
     *
     * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being processed.
     * @param int                         $stackPtr  The position where this token was
     *                                               found.
     * @param int                         $currScope The position of the current scope.
     *
     * @return void
     */
    protected function processTokenWithinScope(File $phpcsFile, $stackPtr, $currScope) {
        $tokens = $phpcsFile->getTokens();
        // Determine if this is a function which needs to be examined.
        $conditions = $tokens[$stackPtr]['conditions'];
        end($conditions);
        $deepestScope = key($conditions);
        if ($deepestScope !== $currScope) {
            return;
        }
        $methodName = $phpcsFile->getDeclarationName($stackPtr);
        if ($methodName === null) {
            // Ignore closures.
            return;
        }
        $className = $phpcsFile->getDeclarationName($currScope);
        if (isset($className) === false) {
            $className = '[Anonymous Class]';
        }
        $errorData = [
            $className . '::' . $methodName,
        ];
        $methodNameLc = strtolower($methodName);
        $classNameLc = strtolower($className);
        // Is this a magic method. i.e., is prefixed with "__" ?
        if (preg_match('|^__[^_]|', $methodName) !== 0) {
            $magicPart = substr($methodNameLc, 2);
            if (isset($this->magicMethods[$magicPart]) === true) {
                return;
            }
            $error = 'Method name "%s" is invalid; only PHP magic methods should be prefixed with a double underscore';
            $phpcsFile->addError($error, $stackPtr, 'MethodDoubleUnderscore', $errorData);
        }
        // PHP4 constructors are allowed to break our rules.
        if ($methodNameLc === $classNameLc) {
            return;
        }
        // PHP4 destructors are allowed to break our rules.
        if ($methodNameLc === '_' . $classNameLc) {
            return;
        }
        $methodProps = $phpcsFile->getMethodProperties($stackPtr);
        $scope = $methodProps['scope'];
        $scopeSpecified = $methodProps['scope_specified'];
        if ($methodProps['scope'] === 'private') {
            $isPublic = false;
        }
        else {
            $isPublic = true;
        }
        // If it's a private method, it must have an underscore on the front.
        if ($isPublic === false) {
            if ($methodName[0] !== '_') {
                $error = 'Private method name "%s" must be prefixed with an underscore';
                $phpcsFile->addError($error, $stackPtr, 'PrivateNoUnderscore', $errorData);
                $phpcsFile->recordMetric($stackPtr, 'Private method prefixed with underscore', 'no');
            }
            else {
                $phpcsFile->recordMetric($stackPtr, 'Private method prefixed with underscore', 'yes');
            }
        }
        // If it's not a private method, it must not have an underscore on the front.
        if ($isPublic === true && $scopeSpecified === true && $methodName[0] === '_') {
            $error = '%s method name "%s" must not be prefixed with an underscore';
            $data = [
                ucfirst($scope),
                $errorData[0],
            ];
            $phpcsFile->addError($error, $stackPtr, 'PublicUnderscore', $data);
        }
        $testMethodName = ltrim($methodName, '_');
        if (Common::isCamelCaps($testMethodName, false, true, false) === false) {
            if ($scopeSpecified === true) {
                $error = '%s method name "%s" is not in camel caps format';
                $data = [
                    ucfirst($scope),
                    $errorData[0],
                ];
                $phpcsFile->addError($error, $stackPtr, 'ScopeNotCamelCaps', $data);
            }
            else {
                $error = 'Method name "%s" is not in camel caps format';
                $phpcsFile->addError($error, $stackPtr, 'NotCamelCaps', $errorData);
            }
        }
    }
    
    //end processTokenWithinScope()
    
    /**
     * Processes the tokens outside the scope.
     *
     * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being processed.
     * @param int                         $stackPtr  The position where this token was
     *                                               found.
     *
     * @return void
     */
    protected function processTokenOutsideScope(File $phpcsFile, $stackPtr) {
        $functionName = $phpcsFile->getDeclarationName($stackPtr);
        if ($functionName === null) {
            // Ignore closures.
            return;
        }
        if (ltrim($functionName, '_') === '') {
            // Ignore special functions.
            return;
        }
        $errorData = [
            $functionName,
        ];
        // Is this a magic function. i.e., it is prefixed with "__".
        if (preg_match('|^__[^_]|', $functionName) !== 0) {
            $magicPart = strtolower(substr($functionName, 2));
            if (isset($this->magicFunctions[$magicPart]) === true) {
                return;
            }
            $error = 'Function name "%s" is invalid; only PHP magic methods should be prefixed with a double underscore';
            $phpcsFile->addError($error, $stackPtr, 'FunctionDoubleUnderscore', $errorData);
        }
        // Function names can be in two parts; the package name and
        // the function name.
        $packagePart = '';
        $underscorePos = strrpos($functionName, '_');
        if ($underscorePos === false) {
            $camelCapsPart = $functionName;
        }
        else {
            $packagePart = substr($functionName, 0, $underscorePos);
            $camelCapsPart = substr($functionName, $underscorePos + 1);
            // We don't care about _'s on the front.
            $packagePart = ltrim($packagePart, '_');
        }
        // If it has a package part, make sure the first letter is a capital.
        if ($packagePart !== '') {
            if ($functionName[0] === '_') {
                $error = 'Function name "%s" is invalid; only private methods should be prefixed with an underscore';
                $phpcsFile->addError($error, $stackPtr, 'FunctionUnderscore', $errorData);
            }
            if ($functionName[0] !== strtoupper($functionName[0])) {
                $error = 'Function name "%s" is prefixed with a package name but does not begin with a capital letter';
                $phpcsFile->addError($error, $stackPtr, 'FunctionNoCapital', $errorData);
            }
        }
        // If it doesn't have a camel caps part, it's not valid.
        if (trim($camelCapsPart) === '') {
            $error = 'Function name "%s" is not valid; name appears incomplete';
            $phpcsFile->addError($error, $stackPtr, 'FunctionInvalid', $errorData);
            return;
        }
        $validName = true;
        $newPackagePart = $packagePart;
        $newCamelCapsPart = $camelCapsPart;
        // Every function must have a camel caps part, so check that first.
        if (Common::isCamelCaps($camelCapsPart, false, true, false) === false) {
            $validName = false;
            $newCamelCapsPart = strtolower($camelCapsPart[0]) . substr($camelCapsPart, 1);
        }
        if ($packagePart !== '') {
            // Check that each new word starts with a capital.
            $nameBits = explode('_', $packagePart);
            $nameBits = array_filter($nameBits);
            foreach ($nameBits as $bit) {
                if ($bit[0] !== strtoupper($bit[0])) {
                    $newPackagePart = '';
                    foreach ($nameBits as $bit) {
                        $newPackagePart .= strtoupper($bit[0]) . substr($bit, 1) . '_';
                    }
                    $validName = false;
                    break;
                }
            }
        }
        if ($validName === false) {
            if ($newPackagePart === '') {
                $newName = $newCamelCapsPart;
            }
            else {
                $newName = rtrim($newPackagePart, '_') . '_' . $newCamelCapsPart;
            }
            $error = 'Function name "%s" is invalid; consider "%s" instead';
            $data = $errorData;
            $data[] = $newName;
            $phpcsFile->addError($error, $stackPtr, 'FunctionNameInvalid', $data);
        }
    }
    
    //end processTokenOutsideScope()

}