Add a way for packagers to override some installation details

[mediawiki.git] / includes / Status.php

<?php
/**
 * Generic operation result.
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 2 of the License, or
 * (at your option) any later version.
 *
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; if not, write to the Free Software Foundation, Inc.,
 * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
 * http://www.gnu.org/copyleft/gpl.html
 *
 * @file
 */

/**
 * Generic operation result class
 * Has warning/error list, boolean status and arbitrary value
 *
 * "Good" means the operation was completed with no warnings or errors.
 *
 * "OK" means the operation was partially or wholly completed.
 *
 * An operation which is not OK should have errors so that the user can be
 * informed as to what went wrong. Calling the fatal() function sets an error
 * message and simultaneously switches off the OK flag.
 */
class Status {
        var $ok = true;
        var $value;

        /** Counters for batch operations */
        public $successCount = 0, $failCount = 0;
        /** Array to indicate which items of the batch operations were successful */
        public $success = array();

        /*semi-private*/ var $errors = array();
        /*semi-private*/ var $cleanCallback = false;

        /**
         * Factory function for fatal errors
         *
         * @param $message String: message name
         * @return Status
         */
        static function newFatal( $message /*, parameters...*/ ) {
                $params = func_get_args();
                $result = new self;
                call_user_func_array( array( &$result, 'error' ), $params );
                $result->ok = false;
                return $result;
        }

        /**
         * Factory function for good results
         *
         * @param $value Mixed
         * @return Status
         */
        static function newGood( $value = null ) {
                $result = new self;
                $result->value = $value;
                return $result;
        }

        /**
         * Change operation result
         *
         * @param $ok Boolean: whether the operation completed
         * @param $value Mixed
         */
        function setResult( $ok, $value = null ) {
                $this->ok = $ok;
                $this->value = $value;
        }

        /**
         * Returns whether the operation completed and didn't have any error or
         * warnings
         *
         * @return Boolean
         */
        function isGood() {
                return $this->ok && !$this->errors;
        }

        /**
         * Returns whether the operation completed
         *
         * @return Boolean
         */
        function isOK() {
                return $this->ok;
        }

        /**
         * Add a new warning
         *
         * @param $message String: message name
         */
        function warning( $message /*, parameters... */ ) {
                $params = array_slice( func_get_args(), 1 );
                $this->errors[] = array(
                        'type' => 'warning',
                        'message' => $message,
                        'params' => $params );
        }

        /**
         * Add an error, do not set fatal flag
         * This can be used for non-fatal errors
         *
         * @param $message String: message name
         */
        function error( $message /*, parameters... */ ) {
                $params = array_slice( func_get_args(), 1 );
                $this->errors[] = array(
                        'type' => 'error',
                        'message' => $message,
                        'params' => $params );
        }

        /**
         * Add an error and set OK to false, indicating that the operation
         * as a whole was fatal
         *
         * @param $message String: message name
         */
        function fatal( $message /*, parameters... */ ) {
                $params = array_slice( func_get_args(), 1 );
                $this->errors[] = array(
                        'type' => 'error',
                        'message' => $message,
                        'params' => $params );
                $this->ok = false;
        }

        /**
         * Sanitize the callback parameter on wakeup, to avoid arbitrary execution.
         */
        function __wakeup() {
                $this->cleanCallback = false;
        }

        /**
         * @param $params array
         * @return array
         */
        protected function cleanParams( $params ) {
                if ( !$this->cleanCallback ) {
                        return $params;
                }
                $cleanParams = array();
                foreach ( $params as $i => $param ) {
                        $cleanParams[$i] = call_user_func( $this->cleanCallback, $param );
                }
                return $cleanParams;
        }

        /**
         * @param $item
         * @return string
         */
        protected function getItemXML( $item ) {
                $params = $this->cleanParams( $item['params'] );
                $xml = "<{$item['type']}>\n" .
                        Xml::element( 'message', null, $item['message'] ) . "\n" .
                        Xml::element( 'text', null, wfMsg( $item['message'], $params ) ) ."\n";
                foreach ( $params as $param ) {
                        $xml .= Xml::element( 'param', null, $param );
                }
                $xml .= "</{$item['type']}>\n";
                return $xml;
        }

        /**
         * Get the error list as XML
         * @return string
         */
        function getXML() {
                $xml = "<errors>\n";
                foreach ( $this->errors as $error ) {
                        $xml .= $this->getItemXML( $error );
                }
                $xml .= "</errors>\n";
                return $xml;
        }

        /**
         * Get the error list as a wikitext formatted list
         *
         * @param $shortContext String: a short enclosing context message name, to
         *        be used when there is a single error
         * @param $longContext String: a long enclosing context message name, for a list
         * @return String
         */
        function getWikiText( $shortContext = false, $longContext = false ) {
                if ( count( $this->errors ) == 0 ) {
                        if ( $this->ok ) {
                                $this->fatal( 'internalerror_info',
                                        __METHOD__." called for a good result, this is incorrect\n" );
                        } else {
                                $this->fatal( 'internalerror_info',
                                        __METHOD__.": Invalid result object: no error text but not OK\n" );
                        }
                }
                if ( count( $this->errors ) == 1 ) {
                        $s = $this->getWikiTextForError( $this->errors[0], $this->errors[0]  );
                        if ( $shortContext ) {
                                $s = wfMsgNoTrans( $shortContext, $s );
                        } elseif ( $longContext ) {
                                $s = wfMsgNoTrans( $longContext, "* $s\n" );
                        }
                } else {
                        $s = '* '. implode("\n* ",
                                $this->getWikiTextArray( $this->errors ) ) . "\n";
                        if ( $longContext ) {
                                $s = wfMsgNoTrans( $longContext, $s );
                        } elseif ( $shortContext ) {
                                $s = wfMsgNoTrans( $shortContext, "\n$s\n" );
                        }
                }
                return $s;
        }

        /**
         * Return the wiki text for a single error.
         * @param $error Mixed With an array & two values keyed by
         * 'message' and 'params', use those keys-value pairs.
         * Otherwise, if its an array, just use the first value as the
         * message and the remaining items as the params.
         *
         * @return String
         */
        protected function getWikiTextForError( $error ) {
                if ( is_array( $error ) ) {
                        if ( isset( $error['message'] ) && isset( $error['params'] ) ) {
                                return wfMsgNoTrans( $error['message'],
                                        array_map( 'wfEscapeWikiText', $this->cleanParams( $error['params'] ) )  );
                        } else {
                                $message = array_shift($error);
                                return wfMsgNoTrans( $message,
                                        array_map( 'wfEscapeWikiText', $this->cleanParams( $error ) ) );
                        }
                } else {
                        return wfMsgNoTrans( $error );
                }
        }

        /**
         * Return an array with the wikitext for each item in the array.
         * @param $errors Array
         * @return Array
         */
        function getWikiTextArray( $errors ) {
                return array_map( array( $this, 'getWikiTextForError' ), $errors );
        }

        /**
         * Merge another status object into this one
         *
         * @param $other Status Other Status object
         * @param $overwriteValue Boolean: whether to override the "value" member
         */
        function merge( $other, $overwriteValue = false ) {
                $this->errors = array_merge( $this->errors, $other->errors );
                $this->ok = $this->ok && $other->ok;
                if ( $overwriteValue ) {
                        $this->value = $other->value;
                }
                $this->successCount += $other->successCount;
                $this->failCount += $other->failCount;
        }

        /**
         * Get the list of errors (but not warnings)
         *
         * @return Array
         */
        function getErrorsArray() {
                return $this->getStatusArray( "error" );
        }

        /**
         * Get the list of warnings (but not errors)
         *
         * @return Array
         */
        function getWarningsArray() {
                return $this->getStatusArray( "warning" );
        }

        /**
         * Returns a list of status messages of the given type
         * @param $type String
         *
         * @return Array
         */
        protected function getStatusArray( $type ) {
                $result = array();
                foreach ( $this->errors as $error ) {
                        if ( $error['type'] === $type ) {
                                if( $error['params'] ) {
                                        $result[] = array_merge( array( $error['message'] ), $error['params'] );
                                } else {
                                        $result[] = array( $error['message'] );
                                }
                        }
                }
                return $result;
        }

        /**
         * Returns a list of status messages of the given type, with message and
         * params left untouched, like a sane version of getStatusArray
         *
         * @param $type String
         *
         * @return Array
         */
        public function getErrorsByType( $type ) {
                $result = array();
                foreach ( $this->errors as $error ) {
                        if ( $error['type'] === $type ) {
                                $result[] = $error;
                        }
                }
                return $result;
        }

        /**
         * Returns true if the specified message is present as a warning or error
         *
         * @param $msg String: message name
         * @return Boolean
         */
        function hasMessage( $msg ) {
                foreach ( $this->errors as $error ) {
                        if ( $error['message'] === $msg ) {
                                return true;
                        }
                }
                return false;
        }

        /**
         * If the specified source message exists, replace it with the specified
         * destination message, but keep the same parameters as in the original error.
         *
         * Return true if the replacement was done, false otherwise.
         *
         * @return bool
         */
        function replaceMessage( $source, $dest ) {
                $replaced = false;
                foreach ( $this->errors as $index => $error ) {
                        if ( $error['message'] === $source ) {
                                $this->errors[$index]['message'] = $dest;
                                $replaced = true;
                        }
                }
                return $replaced;
        }

        /**
         * Backward compatibility function for WikiError -> Status migration
         *
         * @return String
         */
        public function getMessage() {
                return $this->getWikiText();
        }

        /**
         * @return mixed
         */
        public function getValue() {
                return $this->value;
        }
}