<?php
/**
 * Parses and verifies the doc comments for functions.
 *
 * @author    Greg Sherwood <gsherwood@squiz.net>
 * @copyright 2006-2015 Squiz Pty Ltd (ABN 77 084 670 600)
 * @license   https://github.com/squizlabs/PHP_CodeSniffer/blob/master/licence.txt BSD Licence
 */

namespace PHP_CodeSniffer\Standards\Squiz\Sniffs\Commenting;

use PHP_CodeSniffer\Standards\PEAR\Sniffs\Commenting\FunctionCommentSniff as PEARFunctionCommentSniff;
use PHP_CodeSniffer\Files\File;
use PHP_CodeSniffer\Config;
use PHP_CodeSniffer\Util\Common;

class FunctionCommentSniff extends PEARFunctionCommentSniff
{

    /**
     * The current PHP version.
     *
     * @var integer
     */
    private $phpVersion = null;


    /**
     * Process the return comment of this function comment.
     *
     * @param \PHP_CodeSniffer\Files\File $phpcsFile    The file being scanned.
     * @param int                         $stackPtr     The position of the current token
     *                                                  in the stack passed in $tokens.
     * @param int                         $commentStart The position in the stack where the comment started.
     *
     * @return void
     */
    protected function processReturn(File $phpcsFile, $stackPtr, $commentStart)
    {
        $tokens = $phpcsFile->getTokens();
        $return = null;

        foreach ($tokens[$commentStart]['comment_tags'] as $tag) {
            if ($tokens[$tag]['content'] === '@return') {
                if ($return !== null) {
                    $error = 'Only 1 @return tag is allowed in a function comment';
                    $phpcsFile->addError($error, $tag, 'DuplicateReturn');
                    return;
                }

                $return = $tag;
            }
        }

        // Skip constructor and destructor.
        $methodName      = $phpcsFile->getDeclarationName($stackPtr);
        $isSpecialMethod = ($methodName === '__construct' || $methodName === '__destruct');
        if ($isSpecialMethod === true) {
            return;
        }

        if ($return !== null) {
            $content = $tokens[($return + 2)]['content'];
            if (empty($content) === true || $tokens[($return + 2)]['code'] !== T_DOC_COMMENT_STRING) {
                $error = 'Return type missing for @return tag in function comment';
                $phpcsFile->addError($error, $return, 'MissingReturnType');
            } else {
                // Support both a return type and a description.
                preg_match('`^((?:\|?(?:array\([^\)]*\)|[\\\\a-z0-9\[\]]+))*)( .*)?`i', $content, $returnParts);
                if (isset($returnParts[1]) === false) {
                    return;
                }

                $returnType = $returnParts[1];

                // Check return type (can be multiple, separated by '|').
                $typeNames      = explode('|', $returnType);
                $suggestedNames = [];
                foreach ($typeNames as $i => $typeName) {
                    $suggestedName = Common::suggestType($typeName);
                    if (in_array($suggestedName, $suggestedNames, true) === false) {
                        $suggestedNames[] = $suggestedName;
                    }
                }

                $suggestedType = implode('|', $suggestedNames);
                if ($returnType !== $suggestedType) {
                    $error = 'Expected "%s" but found "%s" for function return type';
                    $data  = [
                        $suggestedType,
                        $returnType,
                    ];
                    $fix   = $phpcsFile->addFixableError($error, $return, 'InvalidReturn', $data);
                    if ($fix === true) {
                        $replacement = $suggestedType;
                        if (empty($returnParts[2]) === false) {
                            $replacement .= $returnParts[2];
                        }

                        $phpcsFile->fixer->replaceToken(($return + 2), $replacement);
                        unset($replacement);
                    }
                }

                // If the return type is void, make sure there is
                // no return statement in the function.
                if ($returnType === 'void') {
                    if (isset($tokens[$stackPtr]['scope_closer']) === true) {
                        $endToken = $tokens[$stackPtr]['scope_closer'];
                        for ($returnToken = $stackPtr; $returnToken < $endToken; $returnToken++) {
                            if ($tokens[$returnToken]['code'] === T_CLOSURE
                                || $tokens[$returnToken]['code'] === T_ANON_CLASS
                            ) {
                                $returnToken = $tokens[$returnToken]['scope_closer'];
                                continue;
                            }

                            if ($tokens[$returnToken]['code'] === T_RETURN
                                || $tokens[$returnToken]['code'] === T_YIELD
                                || $tokens[$returnToken]['code'] === T_YIELD_FROM
                            ) {
                                break;
                            }
                        }

                        if ($returnToken !== $endToken) {
                            // If the function is not returning anything, just
                            // exiting, then there is no problem.
                            $semicolon = $phpcsFile->findNext(T_WHITESPACE, ($returnToken + 1), null, true);
                            if ($tokens[$semicolon]['code'] !== T_SEMICOLON) {
                                $error = 'Function return type is void, but function contains return statement';
                                $phpcsFile->addError($error, $return, 'InvalidReturnVoid');
                            }
                        }
                    }//end if
                } else if ($returnType !== 'mixed' && in_array('void', $typeNames, true) === false) {
                    // If return type is not void, there needs to be a return statement
                    // somewhere in the function that returns something.
                    if (isset($tokens[$stackPtr]['scope_closer']) === true) {
                        $endToken = $tokens[$stackPtr]['scope_closer'];
                        for ($returnToken = $stackPtr; $returnToken < $endToken; $returnToken++) {
                            if ($tokens[$returnToken]['code'] === T_CLOSURE
                                || $tokens[$returnToken]['code'] === T_ANON_CLASS
                            ) {
                                $returnToken = $tokens[$returnToken]['scope_closer'];
                                continue;
                            }

                            if ($tokens[$returnToken]['code'] === T_RETURN
                                || $tokens[$returnToken]['code'] === T_YIELD
                                || $tokens[$returnToken]['code'] === T_YIELD_FROM
                            ) {
                                break;
                            }
                        }

                        if ($returnToken === $endToken) {
                            $error = 'Function return type is not void, but function has no return statement';
                            $phpcsFile->addError($error, $return, 'InvalidNoReturn');
                        } else {
                            $semicolon = $phpcsFile->findNext(T_WHITESPACE, ($returnToken + 1), null, true);
                            if ($tokens[$semicolon]['code'] === T_SEMICOLON) {
                                $error = 'Function return type is not void, but function is returning void here';
                                $phpcsFile->addError($error, $returnToken, 'InvalidReturnNotVoid');
                            }
                        }
                    }//end if
                }//end if
            }//end if
        } else {
            $error = 'Missing @return tag in function comment';
            $phpcsFile->addError($error, $tokens[$commentStart]['comment_closer'], 'MissingReturn');
        }//end if

    }//end processReturn()


    /**
     * Process any throw tags that this function comment has.
     *
     * @param \PHP_CodeSniffer\Files\File $phpcsFile    The file being scanned.
     * @param int                         $stackPtr     The position of the current token
     *                                                  in the stack passed in $tokens.
     * @param int                         $commentStart The position in the stack where the comment started.
     *
     * @return void
     */
    protected function processThrows(File $phpcsFile, $stackPtr, $commentStart)
    {
        $tokens = $phpcsFile->getTokens();

        foreach ($tokens[$commentStart]['comment_tags'] as $pos => $tag) {
            if ($tokens[$tag]['content'] !== '@throws') {
                continue;
            }

            $exception = null;
            $comment   = null;
            if ($tokens[($tag + 2)]['code'] === T_DOC_COMMENT_STRING) {
                $matches = [];
                preg_match('/([^\s]+)(?:\s+(.*))?/', $tokens[($tag + 2)]['content'], $matches);
                $exception = $matches[1];
                if (isset($matches[2]) === true && trim($matches[2]) !== '') {
                    $comment = $matches[2];
                }
            }

            if ($exception === null) {
                $error = 'Exception type and comment missing for @throws tag in function comment';
                $phpcsFile->addError($error, $tag, 'InvalidThrows');
            } else if ($comment === null) {
                $error = 'Comment missing for @throws tag in function comment';
                $phpcsFile->addError($error, $tag, 'EmptyThrows');
            } else {
                // Any strings until the next tag belong to this comment.
                if (isset($tokens[$commentStart]['comment_tags'][($pos + 1)]) === true) {
                    $end = $tokens[$commentStart]['comment_tags'][($pos + 1)];
                } else {
                    $end = $tokens[$commentStart]['comment_closer'];
                }

                for ($i = ($tag + 3); $i < $end; $i++) {
                    if ($tokens[$i]['code'] === T_DOC_COMMENT_STRING) {
                        $comment .= ' '.$tokens[$i]['content'];
                    }
                }

                // Starts with a capital letter and ends with a fullstop.
                $firstChar = $comment[0];
                if (strtoupper($firstChar) !== $firstChar) {
                    $error = '@throws tag comment must start with a capital letter';
                    $phpcsFile->addError($error, ($tag + 2), 'ThrowsNotCapital');
                }

                $lastChar = substr($comment, -1);
                if ($lastChar !== '.') {
                    $error = '@throws tag comment must end with a full stop';
                    $phpcsFile->addError($error, ($tag + 2), 'ThrowsNoFullStop');
                }
            }//end if
        }//end foreach

    }//end processThrows()


    /**
     * Process the function parameter comments.
     *
     * @param \PHP_CodeSniffer\Files\File $phpcsFile    The file being scanned.
     * @param int                         $stackPtr     The position of the current token
     *                                                  in the stack passed in $tokens.
     * @param int                         $commentStart The position in the stack where the comment started.
     *
     * @return void
     */
    protected function processParams(File $phpcsFile, $stackPtr, $commentStart)
    {
        if ($this->phpVersion === null) {
            $this->phpVersion = Config::getConfigData('php_version');
            if ($this->phpVersion === null) {
                $this->phpVersion = PHP_VERSION_ID;
            }
        }

        $tokens = $phpcsFile->getTokens();

        $params  = [];
        $maxType = 0;
        $maxVar  = 0;
        foreach ($tokens[$commentStart]['comment_tags'] as $pos => $tag) {
            if ($tokens[$tag]['content'] !== '@param') {
                continue;
            }

            $type         = '';
            $typeSpace    = 0;
            $var          = '';
            $varSpace     = 0;
            $comment      = '';
            $commentLines = [];
            if ($tokens[($tag + 2)]['code'] === T_DOC_COMMENT_STRING) {
                $matches = [];
                preg_match('/([^$&.]+)(?:((?:\.\.\.)?(?:\$|&)[^\s]+)(?:(\s+)(.*))?)?/', $tokens[($tag + 2)]['content'], $matches);

                if (empty($matches) === false) {
                    $typeLen   = strlen($matches[1]);
                    $type      = trim($matches[1]);
                    $typeSpace = ($typeLen - strlen($type));
                    $typeLen   = strlen($type);
                    if ($typeLen > $maxType) {
                        $maxType = $typeLen;
                    }
                }

                if (isset($matches[2]) === true) {
                    $var    = $matches[2];
                    $varLen = strlen($var);
                    if ($varLen > $maxVar) {
                        $maxVar = $varLen;
                    }

                    if (isset($matches[4]) === true) {
                        $varSpace       = strlen($matches[3]);
                        $comment        = $matches[4];
                        $commentLines[] = [
                            'comment' => $comment,
                            'token'   => ($tag + 2),
                            'indent'  => $varSpace,
                        ];

                        // Any strings until the next tag belong to this comment.
                        if (isset($tokens[$commentStart]['comment_tags'][($pos + 1)]) === true) {
                            $end = $tokens[$commentStart]['comment_tags'][($pos + 1)];
                        } else {
                            $end = $tokens[$commentStart]['comment_closer'];
                        }

                        for ($i = ($tag + 3); $i < $end; $i++) {
                            if ($tokens[$i]['code'] === T_DOC_COMMENT_STRING) {
                                $indent = 0;
                                if ($tokens[($i - 1)]['code'] === T_DOC_COMMENT_WHITESPACE) {
                                    $indent = $tokens[($i - 1)]['length'];
                                }

                                $comment       .= ' '.$tokens[$i]['content'];
                                $commentLines[] = [
                                    'comment' => $tokens[$i]['content'],
                                    'token'   => $i,
                                    'indent'  => $indent,
                                ];
                            }
                        }
                    } else {
                        $error = 'Missing parameter comment';
                        $phpcsFile->addError($error, $tag, 'MissingParamComment');
                        $commentLines[] = ['comment' => ''];
                    }//end if
                } else {
                    $error = 'Missing parameter name';
                    $phpcsFile->addError($error, $tag, 'MissingParamName');
                }//end if
            } else {
                $error = 'Missing parameter type';
                $phpcsFile->addError($error, $tag, 'MissingParamType');
            }//end if

            $params[] = [
                'tag'          => $tag,
                'type'         => $type,
                'var'          => $var,
                'comment'      => $comment,
                'commentLines' => $commentLines,
                'type_space'   => $typeSpace,
                'var_space'    => $varSpace,
            ];
        }//end foreach

        $realParams  = $phpcsFile->getMethodParameters($stackPtr);
        $foundParams = [];

        // We want to use ... for all variable length arguments, so added
        // this prefix to the variable name so comparisons are easier.
        foreach ($realParams as $pos => $param) {
            if ($param['variable_length'] === true) {
                $realParams[$pos]['name'] = '...'.$realParams[$pos]['name'];
            }
        }

        foreach ($params as $pos => $param) {
            // If the type is empty, the whole line is empty.
            if ($param['type'] === '') {
                continue;
            }

            // Check the param type value.
            $typeNames          = explode('|', $param['type']);
            $suggestedTypeNames = [];

            foreach ($typeNames as $typeName) {
                // Strip nullable operator.
                if ($typeName[0] === '?') {
                    $typeName = substr($typeName, 1);
                }

                $suggestedName        = Common::suggestType($typeName);
                $suggestedTypeNames[] = $suggestedName;

                if (count($typeNames) > 1) {
                    continue;
                }

                // Check type hint for array and custom type.
                $suggestedTypeHint = '';
                if (strpos($suggestedName, 'array') !== false || substr($suggestedName, -2) === '[]') {
                    $suggestedTypeHint = 'array';
                } else if (strpos($suggestedName, 'callable') !== false) {
                    $suggestedTypeHint = 'callable';
                } else if (strpos($suggestedName, 'callback') !== false) {
                    $suggestedTypeHint = 'callable';
                } else if (in_array($suggestedName, Common::$allowedTypes, true) === false) {
                    $suggestedTypeHint = $suggestedName;
                }

                if ($this->phpVersion >= 70000) {
                    if ($suggestedName === 'string') {
                        $suggestedTypeHint = 'string';
                    } else if ($suggestedName === 'int' || $suggestedName === 'integer') {
                        $suggestedTypeHint = 'int';
                    } else if ($suggestedName === 'float') {
                        $suggestedTypeHint = 'float';
                    } else if ($suggestedName === 'bool' || $suggestedName === 'boolean') {
                        $suggestedTypeHint = 'bool';
                    }
                }

                if ($this->phpVersion >= 70200) {
                    if ($suggestedName === 'object') {
                        $suggestedTypeHint = 'object';
                    }
                }

                if ($suggestedTypeHint !== '' && isset($realParams[$pos]) === true) {
                    $typeHint = $realParams[$pos]['type_hint'];

                    // Remove namespace prefixes when comparing.
                    $compareTypeHint = substr($suggestedTypeHint, (strlen($typeHint) * -1));

                    if ($typeHint === '') {
                        $error = 'Type hint "%s" missing for %s';
                        $data  = [
                            $suggestedTypeHint,
                            $param['var'],
                        ];

                        $errorCode = 'TypeHintMissing';
                        if ($suggestedTypeHint === 'string'
                            || $suggestedTypeHint === 'int'
                            || $suggestedTypeHint === 'float'
                            || $suggestedTypeHint === 'bool'
                        ) {
                            $errorCode = 'Scalar'.$errorCode;
                        }

                        $phpcsFile->addError($error, $stackPtr, $errorCode, $data);
                    } else if ($typeHint !== $compareTypeHint && $typeHint !== '?'.$compareTypeHint) {
                        $error = 'Expected type hint "%s"; found "%s" for %s';
                        $data  = [
                            $suggestedTypeHint,
                            $typeHint,
                            $param['var'],
                        ];
                        $phpcsFile->addError($error, $stackPtr, 'IncorrectTypeHint', $data);
                    }//end if
                } else if ($suggestedTypeHint === '' && isset($realParams[$pos]) === true) {
                    $typeHint = $realParams[$pos]['type_hint'];
                    if ($typeHint !== '') {
                        $error = 'Unknown type hint "%s" found for %s';
                        $data  = [
                            $typeHint,
                            $param['var'],
                        ];
                        $phpcsFile->addError($error, $stackPtr, 'InvalidTypeHint', $data);
                    }
                }//end if
            }//end foreach

            $suggestedType = implode('|', $suggestedTypeNames);
            if ($param['type'] !== $suggestedType) {
                $error = 'Expected "%s" but found "%s" for parameter type';
                $data  = [
                    $suggestedType,
                    $param['type'],
                ];

                $fix = $phpcsFile->addFixableError($error, $param['tag'], 'IncorrectParamVarName', $data);
                if ($fix === true) {
                    $phpcsFile->fixer->beginChangeset();

                    $content  = $suggestedType;
                    $content .= str_repeat(' ', $param['type_space']);
                    $content .= $param['var'];
                    $content .= str_repeat(' ', $param['var_space']);
                    if (isset($param['commentLines'][0]) === true) {
                        $content .= $param['commentLines'][0]['comment'];
                    }

                    $phpcsFile->fixer->replaceToken(($param['tag'] + 2), $content);

                    // Fix up the indent of additional comment lines.
                    foreach ($param['commentLines'] as $lineNum => $line) {
                        if ($lineNum === 0
                            || $param['commentLines'][$lineNum]['indent'] === 0
                        ) {
                            continue;
                        }

                        $diff      = (strlen($param['type']) - strlen($suggestedType));
                        $newIndent = ($param['commentLines'][$lineNum]['indent'] - $diff);
                        $phpcsFile->fixer->replaceToken(
                            ($param['commentLines'][$lineNum]['token'] - 1),
                            str_repeat(' ', $newIndent)
                        );
                    }

                    $phpcsFile->fixer->endChangeset();
                }//end if
            }//end if

            if ($param['var'] === '') {
                continue;
            }

            $foundParams[] = $param['var'];

            // Check number of spaces after the type.
            $this->checkSpacingAfterParamType($phpcsFile, $param, $maxType);

            // Make sure the param name is correct.
            if (isset($realParams[$pos]) === true) {
                $realName = $realParams[$pos]['name'];
                if ($realName !== $param['var']) {
                    $code = 'ParamNameNoMatch';
                    $data = [
                        $param['var'],
                        $realName,
                    ];

                    $error = 'Doc comment for parameter %s does not match ';
                    if (strtolower($param['var']) === strtolower($realName)) {
                        $error .= 'case of ';
                        $code   = 'ParamNameNoCaseMatch';
                    }

                    $error .= 'actual variable name %s';

                    $phpcsFile->addError($error, $param['tag'], $code, $data);
                }
            } else if (substr($param['var'], -4) !== ',...') {
                // We must have an extra parameter comment.
                $error = 'Superfluous parameter comment';
                $phpcsFile->addError($error, $param['tag'], 'ExtraParamComment');
            }//end if

            if ($param['comment'] === '') {
                continue;
            }

            // Check number of spaces after the var name.
            $this->checkSpacingAfterParamName($phpcsFile, $param, $maxVar);

            // Param comments must start with a capital letter and end with a full stop.
            if (preg_match('/^(\p{Ll}|\P{L})/u', $param['comment']) === 1) {
                $error = 'Parameter comment must start with a capital letter';
                $phpcsFile->addError($error, $param['tag'], 'ParamCommentNotCapital');
            }

            $lastChar = substr($param['comment'], -1);
            if ($lastChar !== '.') {
                $error = 'Parameter comment must end with a full stop';
                $phpcsFile->addError($error, $param['tag'], 'ParamCommentFullStop');
            }
        }//end foreach

        $realNames = [];
        foreach ($realParams as $realParam) {
            $realNames[] = $realParam['name'];
        }

        // Report missing comments.
        $diff = array_diff($realNames, $foundParams);
        foreach ($diff as $neededParam) {
            $error = 'Doc comment for parameter "%s" missing';
            $data  = [$neededParam];
            $phpcsFile->addError($error, $commentStart, 'MissingParamTag', $data);
        }

    }//end processParams()


    /**
     * Check the spacing after the type of a parameter.
     *
     * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being scanned.
     * @param array                       $param     The parameter to be checked.
     * @param int                         $maxType   The maxlength of the longest parameter type.
     * @param int                         $spacing   The number of spaces to add after the type.
     *
     * @return void
     */
    protected function checkSpacingAfterParamType(File $phpcsFile, $param, $maxType, $spacing=1)
    {
        // Check number of spaces after the type.
        $spaces = ($maxType - strlen($param['type']) + $spacing);
        if ($param['type_space'] !== $spaces) {
            $error = 'Expected %s spaces after parameter type; %s found';
            $data  = [
                $spaces,
                $param['type_space'],
            ];

            $fix = $phpcsFile->addFixableError($error, $param['tag'], 'SpacingAfterParamType', $data);
            if ($fix === true) {
                $phpcsFile->fixer->beginChangeset();

                $content  = $param['type'];
                $content .= str_repeat(' ', $spaces);
                $content .= $param['var'];
                $content .= str_repeat(' ', $param['var_space']);
                $content .= $param['commentLines'][0]['comment'];
                $phpcsFile->fixer->replaceToken(($param['tag'] + 2), $content);

                // Fix up the indent of additional comment lines.
                $diff = ($param['type_space'] - $spaces);
                foreach ($param['commentLines'] as $lineNum => $line) {
                    if ($lineNum === 0
                        || $param['commentLines'][$lineNum]['indent'] === 0
                    ) {
                        continue;
                    }

                    $newIndent = ($param['commentLines'][$lineNum]['indent'] - $diff);
                    if ($newIndent <= 0) {
                        continue;
                    }

                    $phpcsFile->fixer->replaceToken(
                        ($param['commentLines'][$lineNum]['token'] - 1),
                        str_repeat(' ', $newIndent)
                    );
                }

                $phpcsFile->fixer->endChangeset();
            }//end if
        }//end if

    }//end checkSpacingAfterParamType()


    /**
     * Check the spacing after the name of a parameter.
     *
     * @param \PHP_CodeSniffer\Files\File $phpcsFile The file being scanned.
     * @param array                       $param     The parameter to be checked.
     * @param int                         $maxVar    The maxlength of the longest parameter name.
     * @param int                         $spacing   The number of spaces to add after the type.
     *
     * @return void
     */
    protected function checkSpacingAfterParamName(File $phpcsFile, $param, $maxVar, $spacing=1)
    {
        // Check number of spaces after the var name.
        $spaces = ($maxVar - strlen($param['var']) + $spacing);
        if ($param['var_space'] !== $spaces) {
            $error = 'Expected %s spaces after parameter name; %s found';
            $data  = [
                $spaces,
                $param['var_space'],
            ];

            $fix = $phpcsFile->addFixableError($error, $param['tag'], 'SpacingAfterParamName', $data);
            if ($fix === true) {
                $phpcsFile->fixer->beginChangeset();

                $content  = $param['type'];
                $content .= str_repeat(' ', $param['type_space']);
                $content .= $param['var'];
                $content .= str_repeat(' ', $spaces);
                $content .= $param['commentLines'][0]['comment'];
                $phpcsFile->fixer->replaceToken(($param['tag'] + 2), $content);

                // Fix up the indent of additional comment lines.
                foreach ($param['commentLines'] as $lineNum => $line) {
                    if ($lineNum === 0
                        || $param['commentLines'][$lineNum]['indent'] === 0
                    ) {
                        continue;
                    }

                    $diff      = ($param['var_space'] - $spaces);
                    $newIndent = ($param['commentLines'][$lineNum]['indent'] - $diff);
                    if ($newIndent <= 0) {
                        continue;
                    }

                    $phpcsFile->fixer->replaceToken(
                        ($param['commentLines'][$lineNum]['token'] - 1),
                        str_repeat(' ', $newIndent)
                    );
                }

                $phpcsFile->fixer->endChangeset();
            }//end if
        }//end if

    }//end checkSpacingAfterParamName()


}//end class
