<?php

/**
 * An individual blog post.
 *
 * @package silverstripe
 * @subpackage blog
 *
 * @method ManyManyList Categories()
 * @method ManyManyList Tags()
 * @method ManyManyList Authors()
 * @method Blog Parent()
 *
 * @property string $PublishDate
 * @property string $AuthorNames
 * @property int $ParentID
 */
class BlogPost extends Page
{
    /**
     * Same as above, but for list of users that can be
     * given credit in the author field for blog posts
     * @var string|bool false or group code
     */
    private static $restrict_authors_to_group = false;

    /**
     * @var array
     */
    private static $db = array(
        'PublishDate' => 'SS_Datetime',
        'AuthorNames' => 'Varchar(1024)',
        'Summary' => 'HTMLText',
    );

    /**
     * @var array
     */
    private static $has_one = array(
        'FeaturedImage' => 'Image',
    );

    /**
     * @var array
     */
    private static $many_many = array(
        'Categories' => 'BlogCategory',
        'Tags' => 'BlogTag',
        'Authors' => 'Member',
    );

    /**
     * @var array
     */
    private static $defaults = array(
        'ShowInMenus' => false,
        'InheritSideBar' => true,
        'ProvideComments' => true,
    );

    /**
     * @var array
     */
    private static $extensions = array(
        'BlogPostFilter',
    );

    /**
     * @var array
     */
    private static $searchable_fields = array(
        'Title',
    );

    /**
     * @var array
     */
    private static $summary_fields = array(
        'Title',
    );

    /**
     * @var array
     */
    private static $casting = array(
        'Excerpt' => 'HTMLText',
        'Date' => 'SS_Datetime',
    );

    /**
     * @var array
     */
    private static $allowed_children = array();

    /**
     * The default sorting lists BlogPosts with an empty PublishDate at the top.
     *
     * @var string
     */
    private static $default_sort = '"PublishDate" IS NULL DESC, "PublishDate" DESC';

    /**
     * @var bool
     */
    private static $can_be_root = false;

    /**
     * This will display or hide the current class from the SiteTree. This variable can be
     * configured using YAML.
     *
     * @var bool
     */
    private static $show_in_sitetree = false;

    /**
     * Determine the role of the given member.
     *
     * Call be called via template to determine the current user.
     *
     * @example "Hello $RoleOf($CurrentMember.ID)"
     *
     * @param null|int|Member $member
     *
     * @return null|string
     */
    public function RoleOf($member = null)
    {
        $member = $this->getMember($member);

        if (!$member) {
            return null;
        }

        if ($this->isAuthor($member)) {
            return _t('BlogPost.AUTHOR', 'Author');
        }

        $parent = $this->Parent();

        if ($parent instanceof Blog) {
            return $parent->RoleOf($member);
        }

        return null;
    }

    /**
     * Determine if the given member is an author of this post.
     *
     * @param null|Member $member
     *
     * @return bool
     */
    public function isAuthor($member = null)
    {
        if (!$member || !$member->exists()) {
            return false;
        }

        $list = $this->Authors();

        if ($list instanceof UnsavedRelationList) {
            return in_array($member->ID, $list->getIDList());
        }

        return $list->byID($member->ID) !== null;
    }

    /**
     * {@inheritdoc}
     */
    public function getCMSFields()
    {
        Requirements::css(BLOGGER_DIR . '/css/cms.css');
        Requirements::javascript(BLOGGER_DIR . '/js/cms.js');

        $self =& $this;

        $this->beforeUpdateCMSFields(function ($fields) use ($self) {
            $uploadField = UploadField::create('FeaturedImage', _t('BlogPost.FeaturedImage', 'Featured Image'));
            $uploadField->getValidator()->setAllowedExtensions(array('jpg', 'jpeg', 'png', 'gif'));

            /**
             * @var FieldList $fields
             */
            $fields->insertAfter($uploadField, 'Content');

            $summary = HtmlEditorField::create('Summary', false);
            $summary->setRows(5);
            $summary->setDescription(_t(
                'BlogPost.SUMMARY_DESCRIPTION',
                'If no summary is specified the first 30 words will be used.'
            ));

            $summaryHolder = ToggleCompositeField::create(
                'CustomSummary',
                _t('BlogPost.CUSTOMSUMMARY', 'Add A Custom Summary'),
                array(
                    $summary,
                )
            );
            $summaryHolder->setHeadingLevel(4);
            $summaryHolder->addExtraClass('custom-summary');

            $fields->insertAfter($summaryHolder, 'FeaturedImage');

            $fields->push(HiddenField::create('MenuTitle'));

            $urlSegment = $fields->dataFieldByName('URLSegment');
            $urlSegment->setURLPrefix($self->Parent()->RelativeLink());

            $fields->removeFieldsFromTab('Root.Main', array(
                'MenuTitle',
                'URLSegment',
            ));

            $authorField = ListboxField::create(
                'Authors',
                _t('BlogPost.Authors', 'Authors'),
                $self->getCandidateAuthors()->map()->toArray()
            )->setMultiple(true);

            $authorNames = TextField::create(
                'AuthorNames',
                _t('BlogPost.AdditionalCredits', 'Additional Credits'),
                null,
                1024
            )->setDescription(_t(
                    'BlogPost.AdditionalCredits_Description',
                    'If some authors of this post don\'t have CMS access, enter their name(s) here. You can separate multiple names with a comma.')
            );

            if (!$self->canEditAuthors()) {
                $authorField = $authorField->performDisabledTransformation();
                $authorNames = $authorNames->performDisabledTransformation();
            }

            $publishDate = DatetimeField::create('PublishDate', _t('BlogPost.PublishDate', 'Publish Date'));
            $publishDate->getDateField()->setConfig('showcalendar', true);
            if (!$self->PublishDate) {
                $publishDate->setDescription(_t(
                        'BlogPost.PublishDate_Description',
                        'Will be set to "now" if published without a value.')
                );
            }

            // Get categories and tags
            $parent = $self->Parent();
            $categories = $parent instanceof Blog
                ? $parent->Categories()
                : BlogCategory::get();
            $tags = $parent instanceof Blog
                ? $parent->Tags()
                : BlogTag::get();

            $options = BlogAdminSidebar::create(
                $publishDate,
                $urlSegment,
                TagField::create(
                    'Categories',
                    _t('BlogPost.Categories', 'Categories'),
                    $categories,
                    $self->Categories()
                )
                    ->setCanCreate($self->canCreateCategories())
                    ->setShouldLazyLoad(true),
                TagField::create(
                    'Tags',
                    _t('BlogPost.Tags', 'Tags'),
                    $tags,
                    $self->Tags()
                )
                    ->setCanCreate($self->canCreateTags())
                    ->setShouldLazyLoad(true),
                $authorField,
                $authorNames
            )->setTitle('Post Options');

            $options->setName('blog-admin-sidebar');

            $fields->insertBefore($options, 'Root');
        });

        $fields = parent::getCMSFields();

        $fields->fieldByName('Root')->setTemplate('TabSet_holder');

        return $fields;
    }

    /**
     * Gets the list of author candidates to be assigned as authors of this blog post.
     *
     * @return SS_List
     */
    public function getCandidateAuthors()
    {
        if ($this->config()->restrict_authors_to_group) {
            return Group::get()->filter('Code', $this->config()->restrict_authors_to_group)->first()->Members();
        } else {
            $list = Member::get();
            $this->extend('updateCandidateAuthors', $list);
            return $list;
        }
    }

    /**
     * Determine if this user can edit the authors list.
     *
     * @param null|int|Member $member
     *
     * @return bool
     */
    public function canEditAuthors($member = null)
    {
        $member = $this->getMember($member);

        $extended = $this->extendedCan('canEditAuthors', $member);

        if ($extended !== null) {
            return $extended;
        }

        $parent = $this->Parent();

        if ($parent instanceof Blog && $parent->exists()) {
            if ($parent->isEditor($member)) {
                return true;
            }

            if ($parent->isWriter($member) && $this->isAuthor($member)) {
                return true;
            }
        }

        return Permission::checkMember($member, Blog::MANAGE_USERS);
    }

    /**
     * @param null|int|Member $member
     *
     * @return null|Member
     */
    protected function getMember($member = null)
    {
        if (!$member) {
            $member = Member::currentUser();
        }

        if (is_numeric($member)) {
            $member = Member::get()->byID($member);
        }

        return $member;
    }

    /**
     * Determine whether user can create new categories.
     *
     * @param null|int|Member $member
     *
     * @return bool
     */
    public function canCreateCategories($member = null)
    {
        $member = $this->getMember($member);

        $parent = $this->Parent();

        if (!$parent || !$parent->exists() || !($parent instanceof Blog)) {
            return false;
        }

        if ($parent->isEditor($member)) {
            return true;
        }

        return Permission::checkMember($member, 'ADMIN');
    }

    /**
     * Determine whether user can create new tags.
     *
     * @param null|int|Member $member
     *
     * @return bool
     */
    public function canCreateTags($member = null)
    {
        $member = $this->getMember($member);

        $parent = $this->Parent();

        if (!$parent || !$parent->exists() || !($parent instanceof Blog)) {
            return false;
        }

        if ($parent->isEditor($member)) {
            return true;
        }

        if ($parent->isWriter($member)) {
            return true;
        }

        return Permission::checkMember($member, 'ADMIN');
    }

    /**
     * {@inheritdoc}
     *
     * Update the PublishDate to now if the BlogPost would otherwise be published without a date.
     */
    public function onBeforePublish()
    {
        /**
         * @var SS_Datetime $publishDate
         */
        $publishDate = $this->dbObject('PublishDate');

        if (!$publishDate->getValue()) {
            $this->PublishDate = SS_Datetime::now()->getValue();
            $this->write();
        }
    }

    /**
     * {@inheritdoc}
     *
     * Sets blog relationship on all categories and tags assigned to this post.
     */
    public function onAfterWrite()
    {
        parent::onAfterWrite();

        foreach ($this->Categories() as $category) {
            /**
             * @var BlogCategory $category
             */
            $category->BlogID = $this->ParentID;
            $category->write();
        }

        foreach ($this->Tags() as $tag) {
            /**
             * @var BlogTag $tag
             */
            $tag->BlogID = $this->ParentID;
            $tag->write();
        }
    }

    /**
     * {@inheritdoc}
     */
    public function canView($member = null)
    {
        $member = $this->getMember($member);

        if (!parent::canView($member)) {
            return false;
        }

        if ($this->canEdit($member)) {
            return true;
        }

        // If on draft stage, user has permission to view draft, so show it
        if (Versioned::current_stage() === 'Stage') {
            return true;
        }

        /**
         * @var SS_Datetime $publishDate
         */
        $publishDate = $this->dbObject('PublishDate');
        if (!$publishDate->exists()) {
            return false;
        }

        return !$publishDate->InFuture();
    }

    /**
     * {@inheritdoc}
     */
    public function canPublish($member = null)
    {
        $member = $this->getMember($member);

        if (Permission::checkMember($member, 'ADMIN')) {
            return true;
        }

        $extended = $this->extendedCan('canPublish', $member);

        if ($extended !== null) {
            return $extended;
        }

        $parent = $this->Parent();

        if ($parent instanceof Blog && $parent->exists()) {
            if ($parent->isEditor($member)) {
                return true;
            }

            if ($parent->isWriter($member) && $this->isAuthor($member)) {
                return true;
            }

            if ($parent->isContributor($member)) {
                return parent::canEdit($member);
            }
        }

        return $this->canEdit($member);
    }

    /**
     * {@inheritdoc}
     */
    public function canEdit($member = null)
    {
        $member = $this->getMember($member);

        if (parent::canEdit($member)) {
            return true;
        }

        $parent = $this->Parent();

        if (!$parent || !$parent->exists() || !($parent instanceof Blog)) {
            return false;
        }

        if ($parent->isEditor($member)) {
            return true;
        }

        if (!$parent->isWriter($member) && !$parent->isContributor($member)) {
            return false;
        }

        return $this->isAuthor($member);
    }

    /**
     * Returns the post excerpt.
     *
     * @param int $wordsToDisplay
     *
     * @return string
     */
    public function Excerpt($wordsToDisplay = 30)
    {
        /** @var HTMLText $content */
        $content = $this->dbObject('Content');

        return $content->Summary($wordsToDisplay);
    }

    /**
     * Returns a monthly archive link for the current blog post.
     *
     * @param string $type
     *
     * @return string
     */
    public function getMonthlyArchiveLink($type = 'day')
    {
        /**
         * @var SS_Datetime $date
         */
        $date = $this->dbObject('PublishDate');

        if ($type != 'year') {
            if ($type == 'day') {
                return Controller::join_links(
                    $this->Parent()->Link('archive'),
                    $date->format('Y'),
                    $date->format('m'),
                    $date->format('d')
                );
            }

            return Controller::join_links($this->Parent()->Link('archive'), $date->format('Y'), $date->format('m'));
        }

        return Controller::join_links($this->Parent()->Link('archive'), $date->format('Y'));
    }

    /**
     * Returns a yearly archive link for the current blog post.
     *
     * @return string
     */
    public function getYearlyArchiveLink()
    {
        /**
         * @var SS_Datetime $date
         */
        $date = $this->dbObject('PublishDate');

        return Controller::join_links($this->Parent()->Link('archive'), $date->format('Y'));
    }

    /**
     * Resolves static and dynamic authors linked to this post.
     *
     * @return ArrayList
     */
    public function getCredits()
    {
        $list = new ArrayList();

        $list->merge($this->getDynamicCredits());
        $list->merge($this->getStaticCredits());

        return $list->sort('Name');
    }

    /**
     * Resolves dynamic authors linked to this post.
     *
     * @return ArrayList
     */
    protected function getDynamicCredits()
    {
        // Find best page to host user profiles
        $parent = $this->Parent();
        if (! ($parent instanceof Blog)) {
            $parent = Blog::get()->first();
        }

        // If there is no parent blog, return list undecorated
        if (!$parent) {
            $items = $this->Authors()->toArray();
            return new ArrayList($items);
        }

        // Update all authors
        $items = new ArrayList();
        foreach ($this->Authors() as $author) {
            // Add link for each author
            $author = $author->customise(array(
                'URL' => $parent->ProfileLink($author->URLSegment),
            ));
            $items->push($author);
        }

        return $items;
    }

    /**
     * Resolves static authors linked to this post.
     *
     * @return ArrayList
     */
    protected function getStaticCredits()
    {
        $items = new ArrayList();

        $authors = array_filter(preg_split('/\s*,\s*/', $this->AuthorNames));

        foreach ($authors as $author) {
            $item = new ArrayData(array(
                'Name' => $author,
            ));

            $items->push($item);
        }

        return $items;
    }

    /**
     * Sets the label for BlogPost.Title to 'Post Title' (Rather than 'Page name').
     *
     * @param bool $includeRelations
     *
     * @return array
     */
    public function fieldLabels($includeRelations = true)
    {
        $labels = parent::fieldLabels($includeRelations);

        $labels['Title'] = _t('BlogPost.PageTitleLabel', 'Post Title');

        return $labels;
    }

    /**
     * Proxy method for displaying the publish date in rss feeds.
     * @see https://github.com/silverstripe/silverstripe-blog/issues/394
     *
     * @return string|null
     */
    public function getDate()
    {
        if ($this->hasDatabaseField('Date')) {
            return $this->getField('Date');
        }
        return !empty($this->PublishDate) ? $this->PublishDate : null;
    }

    /**
     * {@inheritdoc}
     */
    protected function onBeforeWrite()
    {
        parent::onBeforeWrite();

        if (!$this->exists() && ($member = Member::currentUser())) {
            $this->Authors()->add($member);
        }
    }
}

/**
 * @package silverstripe
 * @subpackage blog
 */
class BlogPost_Controller extends Page_Controller
{
}