<?php
/**
 * Move Plugin Operation Execution
 *
 * @license    GPL 2 (http://www.gnu.org/licenses/gpl.html)
 * @author     Michael Hamann <michael@content-space.de>
 * @author     Gary Owen <gary@isection.co.uk>
 * @author     Andreas Gohr <gohr@cosmocode.de>
 */
// must be run within Dokuwiki
if(!defined('DOKU_INC')) die();

class helper_plugin_move_op extends DokuWiki_Plugin {

    /**
     * @var string symbol to make move operations easily recognizable in change log
     */
    public $symbol = '↷';

    /**
     * @var array stores the affected pages of the last operation
     */
    protected $affectedPages = array();

    /**
     * Check if the given page can be moved to the given destination
     *
     * @param $src
     * @param $dst
     * @return bool
     */
    public function checkPage($src, $dst) {
        // Check we have rights to move this document
        if(!page_exists($src)) {
            msg(sprintf($this->getLang('notexist'), $src), -1);
            return false;
        }
        if(auth_quickaclcheck($src) < AUTH_EDIT) {
            msg(sprintf($this->getLang('norights'), $src), -1);
            return false;
        }

        // Check file is not locked
        // checklock checks if the page lock hasn't expired and the page hasn't been locked by another user
        // the file exists check checks if the page is reported unlocked if a lock exists which means that
        // the page is locked by the current user
        if(checklock($src) !== false || @file_exists(wikiLockFN($src))) {
            msg(sprintf($this->getLang('filelocked'), $src), -1);
            return false;
        }

        // Has the document name and/or namespace changed?
        if($src == $dst) {
            msg(sprintf($this->getLang('notchanged'), $src), -1);
            return false;
        }

        // Check the page does not already exist
        if(page_exists($dst)) {
            msg(sprintf($this->getLang('exists'), $src, $dst), -1);
            return false;
        }

        // Check if the current user can create the new page
        if(auth_quickaclcheck($dst) < AUTH_CREATE) {
            msg(sprintf($this->getLang('notargetperms'), $dst), -1);
            return false;
        }

        return true;
    }

    /**
     * Check if the given media file can be moved to the given destination
     *
     * @param $src
     * @param $dst
     * @return bool
     */
    public function checkMedia($src, $dst) {
        // Check we have rights to move this document
        if(!file_exists(mediaFN($src))) {
            msg(sprintf($this->getLang('medianotexist'), $src), -1);
            return false;
        }
        if(auth_quickaclcheck($src) < AUTH_DELETE) {
            msg(sprintf($this->getLang('nomediarights'), $src), -1);
            return false;
        }

        // Has the document name and/or namespace changed?
        if($src == $dst) {
            msg(sprintf($this->getLang('medianotchanged'), $src), -1);
            return false;
        }

        // Check the page does not already exist
        if(@file_exists(mediaFN($dst))) {
            msg(sprintf($this->getLang('mediaexists'), $src, $dst), -1);
            return false;
        }

        // Check if the current user can create the new page
        if(auth_quickaclcheck($dst) < AUTH_UPLOAD) {
            msg(sprintf($this->getLang('nomediatargetperms'), $dst), -1);
            return false;
        }

        // check if the file extension is unchanged
        if (pathinfo(mediaFN($src), PATHINFO_EXTENSION) !== pathinfo(mediaFN($dst), PATHINFO_EXTENSION)) {
            msg($this->getLang('extensionchange'), -1);
            return false;
        }

        return true;
    }

    /**
     * Execute a page move/rename
     *
     * @param string $src original ID
     * @param string $dst new ID
     * @return bool
     */
    public function movePage($src, $dst) {
        if(!$this->checkPage($src, $dst)) return false;

        // lock rewrites
        helper_plugin_move_rewrite::addLock();

        /** @var helper_plugin_move_rewrite $Rewriter */
        $Rewriter = plugin_load('helper', 'move_rewrite');

        // remember what this page was called before the move in meta data
        $Rewriter->setSelfMoveMeta($src);

        // ft_backlinks() is not used here, as it does a hidden page and acl check but we really need all pages
        $affected_pages = idx_get_indexer()->lookupKey('relation_references', $src);
        $affected_pages[] = $dst; // the current page is always affected, because all relative links may have changed
        $affected_pages = array_unique($affected_pages);

        $src_ns   = getNS($src);
        $src_name = noNS($src);
        $dst_ns   = getNS($dst);
        $dst_name = noNS($dst);

        // pass this info on to other plugins
        $eventdata = array(
            // this is for compatibility to old plugin
            'opts'           => array(
                'ns'      => $src_ns,
                'name'    => $src_name,
                'newns'   => $dst_ns,
                'newname' => $dst_name,
            ),
            'affected_pages' => &$affected_pages,
            'src_id'         => $src,
            'dst_id'         => $dst,
        );

        // give plugins the option to add their own meta files to the list of files that need to be moved
        // to the oldfiles/newfiles array or to adjust their own metadata, database, ...
        // and to add other pages to the affected pages
        $event = new Doku_Event('PLUGIN_MOVE_PAGE_RENAME', $eventdata);
        if($event->advise_before()) {
            lock($src);

            /** @var helper_plugin_move_file $FileMover */
            $FileMover = plugin_load('helper', 'move_file');

            // Move the Subscriptions & Indexes (new feature since Spring 2013 release)
            $Indexer = idx_get_indexer();
            if(($idx_msg = $Indexer->renamePage($src, $dst)) !== true
                || ($idx_msg = $Indexer->renameMetaValue('relation_references', $src, $dst)) !== true
            ) {
                msg(sprintf($this->getLang('indexerror'), $idx_msg), -1);
                return false;
            }
            if(!$FileMover->movePageMeta($src_ns, $src_name, $dst_ns, $dst_name)) {
                msg(sprintf($this->getLang('metamoveerror'), $src), -1);
                return false;
            }

            // prepare the summary for the changelog entry
            if($src_ns == $dst_ns) {
                $lang_key = 'renamed';
            } elseif($src_name == $dst_name) {
                $lang_key = 'moved';
            } else {
                $lang_key = 'move_rename';
            }
            $summary = $this->symbol . ' ' . sprintf($this->getLang($lang_key), $src, $dst);

            // Wait a second when the page has just been rewritten
            $oldRev = filemtime(wikiFN($src));
            if($oldRev == time()) sleep(1);

            // Save the updated document in its new location
            $text = rawWiki($src);
            saveWikiText($dst, $text, $summary);

            // Delete the orginal file
            if(@file_exists(wikiFN($dst))) {
                saveWikiText($src, '', $summary);
            }

            // Move the old revisions
            if(!$FileMover->movePageAttic($src_ns, $src_name, $dst_ns, $dst_name)) {
                // it's too late to stop the move, so just display a message.
                msg(sprintf($this->getLang('atticmoveerror'), $src ), -1);
            }

            // Add meta data to all affected pages, so links get updated later
            foreach($affected_pages as $id) {
                $Rewriter->setMoveMeta($id, $src, $dst, 'pages');
            }

            unlock($src);
        }
        $event->advise_after();

        // store this for later use
        $this->affectedPages = $affected_pages;

        // unlock rewrites
        helper_plugin_move_rewrite::removeLock();

        return true;
    }

    /**
     * Execute a media file move/rename
     *
     * @param string $src original ID
     * @param string $dst new ID
     * @return bool true if the move was successfully executed
     */
    public function moveMedia($src, $dst) {
        if(!$this->checkMedia($src, $dst)) return false;

        // get all pages using this media
        $affected_pages = idx_get_indexer()->lookupKey('relation_media', $src);

        $src_ns   = getNS($src);
        $src_name = noNS($src);
        $dst_ns   = getNS($dst);
        $dst_name = noNS($dst);

        // pass this info on to other plugins
        $eventdata = array(
            // this is for compatibility to old plugin
            'opts'           => array(
                'ns'      => $src_ns,
                'name'    => $src_name,
                'newns'   => $dst_ns,
                'newname' => $dst_name,
            ),
            'affected_pages' => &$affected_pages,
            'src_id'         => $src,
            'dst_id'         => $dst,
        );

        // give plugins the option to add their own meta files to the list of files that need to be moved
        // to the oldfiles/newfiles array or to adjust their own metadata, database, ...
        // and to add other pages to the affected pages
        $event = new Doku_Event('PLUGIN_MOVE_MEDIA_RENAME', $eventdata);
        if($event->advise_before()) {
            /** @var helper_plugin_move_file $FileMover */
            $FileMover = plugin_load('helper', 'move_file');
            /** @var helper_plugin_move_rewrite $Rewriter */
            $Rewriter = plugin_load('helper', 'move_rewrite');

            // Move the Subscriptions & Indexes (new feature since Spring 2013 release)
            $Indexer = idx_get_indexer();
            if(($idx_msg = $Indexer->renameMetaValue('relation_media', $src, $dst)) !== true) {
                msg(sprintf($this->getLang('indexerror'), $idx_msg), -1);
                return false;
            }
            if(!$FileMover->moveMediaMeta($src_ns, $src_name, $dst_ns, $dst_name)) {
                msg(sprintf($this->getLang('mediametamoveerror'), $src), -1);
                return false;
            }

            // prepare directory
            io_createNamespace($dst, 'media');

            // move it FIXME this does not create a changelog entry!
            if(!io_rename(mediaFN($src), mediaFN($dst))) {
                msg(sprintf($this->getLang('mediamoveerror'), $src), -1);
                return false;
            }

            // clean up old ns
            io_sweepNS($src, 'mediadir');

            // Move the old revisions
            if(!$FileMover->moveMediaAttic($src_ns, $src_name, $dst_ns, $dst_name)) {
                // it's too late to stop the move, so just display a message.
                msg(sprintf($this->getLang('mediaatticmoveerror'), $src), -1);
            }

            // Add meta data to all affected pages, so links get updated later
            foreach($affected_pages as $id) {
                $Rewriter->setMoveMeta($id, $src, $dst, 'media');
            }
        }
        $event->advise_after();

        // store this for later use
        $this->affectedPages = $affected_pages;

        return true;
    }

    /**
     * Get a list of pages that where affected by the last successful move operation
     *
     * @return array
     */
    public function getAffectedPages() {
        return $this->affectedPages;
    }
}