<?php
/**
 * WordPress Coding Standard.
 *
 * @package WPCS\WordPressCodingStandards
 * @link    https://github.com/WordPress/WordPress-Coding-Standards
 * @license https://opensource.org/licenses/MIT MIT
 */

namespace WordPressCS\WordPress\Sniffs\DateTime;

use PHP_CodeSniffer\Util\Tokens;
use PHPCSUtils\Utils\PassedParameters;
use PHPCSUtils\Utils\TextStrings;
use WordPressCS\WordPress\AbstractFunctionParameterSniff;

/**
 * Don't use current_time() to get a (timezone corrected) "timestamp".
 *
 * Disallow using the current_time() function to get "timestamps" as it
 * doesn't produce a *real* timestamp, but a "WordPress timestamp", i.e.
 * a Unix timestamp with current timezone offset, not a Unix timestamp ansich.
 *
 * @link https://developer.wordpress.org/reference/functions/current_time/
 * @link https://make.wordpress.org/core/2019/09/23/date-time-improvements-wp-5-3/
 * @link https://core.trac.wordpress.org/ticket/40657
 * @link https://github.com/WordPress/WordPress-Coding-Standards/issues/1791
 *
 * @since 2.2.0
 */
final class CurrentTimeTimestampSniff extends AbstractFunctionParameterSniff {

    /**
     * The group name for this group of functions.
     *
     * @since 2.2.0
     *
     * @var string
     */
    protected $group_name = 'current_time';

    /**
     * List of functions to examine.
     *
     * @since 2.2.0
     *
     * @var array<string, true> Key is function name, value irrelevant.
     */
    protected $target_functions = array(
        'current_time' => true,
    );

    /**
     * Process the parameters of a matched function.
     *
     * @since 2.2.0
     *
     * @param int    $stackPtr        The position of the current token in the stack.
     * @param string $group_name      The name of the group which was matched.
     * @param string $matched_content The token content (function name) which was matched
     *                                in lowercase.
     * @param array  $parameters      Array with information about the parameters.
     *
     * @return void
     */
    public function process_parameters( $stackPtr, $group_name, $matched_content, $parameters ) {
        /*
         * We already know there will be valid open & close parentheses as otherwise the parameter
         * retrieval function call would have returned an empty array, so no additional checks needed.
         */
        $open_parens  = $this->phpcsFile->findNext( \T_OPEN_PARENTHESIS, $stackPtr );
        $close_parens = $this->tokens[ $open_parens ]['parenthesis_closer'];

        /*
         * Check whether the first parameter is a timestamp format.
         */
        $type_param = PassedParameters::getParameterFromStack( $parameters, 1, 'type' );
        if ( false === $type_param ) {
            // Type parameter not found. Bow out.
            return;
        }

        $content_type = '';
        for ( $i = $type_param['start']; $i <= $type_param['end']; $i++ ) {
            if ( isset( Tokens::$emptyTokens[ $this->tokens[ $i ]['code'] ] ) ) {
                continue;
            }

            if ( isset( Tokens::$textStringTokens[ $this->tokens[ $i ]['code'] ] ) ) {
                $content_type = trim( TextStrings::stripQuotes( $this->tokens[ $i ]['content'] ) );
                if ( 'U' !== $content_type && 'timestamp' !== $content_type ) {
                    // Most likely valid use of current_time().
                    return;
                }

                continue;
            }

            if ( isset( Tokens::$heredocTokens[ $this->tokens[ $i ]['code'] ] ) ) {
                continue;
            }

            /*
             * If we're still here, we've encountered an unexpected token, like a variable or
             * function call. Bow out as we can't determine the runtime value.
             */
            return;
        }

        $gmt_true = false;

        /*
         * Check whether the second parameter, $gmt, is a set to `true` or `1`.
         */
        $gmt_param = PassedParameters::getParameterFromStack( $parameters, 2, 'gmt' );
        if ( is_array( $gmt_param ) ) {
            $content_gmt = '';
            if ( 'true' === $gmt_param['clean'] || '1' === $gmt_param['clean'] ) {
                $content_gmt = $gmt_param['clean'];
                $gmt_true    = true;
            }
        }

        /*
         * Non-UTC timestamp requested.
         */
        if ( false === $gmt_true ) {
            $this->phpcsFile->addWarning(
                'Calling current_time() with a $type of "timestamp" or "U" is strongly discouraged as it will not return a Unix (UTC) timestamp. Please consider using a non-timestamp format or otherwise refactoring this code.',
                $stackPtr,
                'Requested'
            );

            return;
        }

        /*
         * UTC timestamp requested. Should use time() instead.
         */
        $has_comment = $this->phpcsFile->findNext( Tokens::$commentTokens, ( $stackPtr + 1 ), ( $close_parens + 1 ) );
        $error       = 'Don\'t use current_time() for retrieving a Unix (UTC) timestamp. Use time() instead. Found: %s';
        $error_code  = 'RequestedUTC';

        $code_snippet = "current_time( '" . $content_type . "'";
        if ( isset( $content_gmt ) ) {
            $code_snippet .= ', ' . $content_gmt;
        }
        $code_snippet .= ' )';

        if ( false !== $has_comment ) {
            // If there are comments, we don't auto-fix as it would remove those comments.
            $this->phpcsFile->addError( $error, $stackPtr, $error_code, array( $code_snippet ) );
            return;
        }

        $fix = $this->phpcsFile->addFixableError( $error, $stackPtr, $error_code, array( $code_snippet ) );
        if ( true === $fix ) {
            $this->phpcsFile->fixer->beginChangeset();

            for ( $i = ( $stackPtr + 1 ); $i < $close_parens; $i++ ) {
                $this->phpcsFile->fixer->replaceToken( $i, '' );
            }

            $this->phpcsFile->fixer->replaceToken( $stackPtr, 'time(' );
            $this->phpcsFile->fixer->endChangeset();
        }
    }
}