<?php



namespace PieCrust\Page;



use \Exception;

use \InvalidArgumentException;

use PieCrust\IPage;

use PieCrust\IPieCrust;

use PieCrust\PieCrustException;

use PieCrust\Data\DataBuilder;

use PieCrust\IO\Cache;

use PieCrust\Util\PieCrustHelper;

use PieCrust\Util\UriParser;

use PieCrust\Util\UriBuilder;





/**

 * A class that represents a page (article or post) in PieCrust.

 *

 */

class Page implements IPage

{

    protected $pieCrust;

    /**

     * Gets the PieCrust app this page belongs to.

     */

    public function getApp()

    {

        return $this->pieCrust;

    }

    

    protected $path;

    /**

     * Gets the file-system path to the page's file.

     */

    public function getPath()

    {

        return $this->path;

    }

    

    protected $uri;

    /**

     * Gets the PieCrust URI to the page.

     */

    public function getUri()

    {

        return $this->uri;

    }

    

    protected $blogKey;

    /**

     * Gets the blog key for this page.

     */

    public function getBlogKey()

    {

        return $this->blogKey;

    }

    

    protected $pageNumber;

    /**

     * Gets the page number (for pages that display a large number of posts).

     */

    public function getPageNumber()

    {

        return $this->pageNumber;

    }

    

    /**

     * Sets the page number.

     */

    public function setPageNumber($pageNumber)

    {

        if ($pageNumber != $this->pageNumber)

        {

            $this->pageNumber = $pageNumber;

            $this->unload();

        }

    }

    

    protected $key;

    /**

     * Gets the page key (e.g. the tag or category)

     */

    public function getPageKey()

    {

        return $this->key;

    }



    /**

     * Sets the page key (e.g. the tag or category)

     */

    public function setPageKey($key)

    {

        if ($key != $this->key)

        {

            $this->key = $key;

            $this->unload();

        }

    }

    

    protected $date;

    protected $dateIsLocked;

    /**

     * Gets the date (and possibly time) this page was created.

     *

     * This loads the page's configuration, unless the date was already

     * specifically set with `setDate` (which is the case for blog posts

     * for example).

     */

    public function getDate()

    {

        if ($this->date === null or !$this->dateIsLocked)

        {

            // Get the date from the file on disk if it was never set.

            // Override with the date from the config if authorized to do so.

            $dateFromConfig = $this->getConfig()->getValue('date');

            if ($dateFromConfig != null)

                $this->date = strtotime($dateFromConfig);

            else if ($this->date === null)

                $this->date = filemtime($this->path);



            // Add/adjust the time of day if needed.

            $timeFromConfig = $this->getConfig()->getValue('time');

            if ($timeFromConfig != null)

                $this->date = strtotime($timeFromConfig, $this->date);



            // Lock the date.

            $this->dateIsLocked = true;

        }

        return $this->date;

    }

    

    /**

     * Sets the date this page was created.

     */

    public function setDate($date, $isLocked = false)

    {

        if ($date !==null && $this->date != $date)

        {

            if (is_int($date))

            {

                $this->date = $date;

                $this->dateIsLocked = $isLocked;

            }

            else if (is_string($date))

            {

                $this->date = strtotime($date);

                $this->dateIsLocked = $isLocked;

            }

            else

            {

                throw new PieCrustException("The date must be an number or a string.");

            }

        }

    }

    

    protected $type;

    /**

     * Gets the page type.

     */

    public function getPageType()

    {

        return $this->type;

    }

    

    protected $wasCached;

    /**

     * Gets whether this page's contents were cached.

     */

    public function wasCached()

    {

        return $this->wasCached;

    }

    

    protected $config;

    /**

     * Gets the page's configuration from its YAML header.

     */

    public function getConfig()

    {

        $this->ensureConfigLoaded();

        return $this->config;

    }

    

    protected $contents;

    protected $formattedContents;

    /**

     * Gets the page's formatted content.

     */

    public function getContentSegment($segment = 'content')

    {

        $this->ensureContentsFormatted();

        return $this->formattedContents[$segment];

    }

    

    /**

     * Returns whether a given content segment exists.

     */

    public function hasContentSegment($segment)

    {

        $this->ensureContentsFormatted();

        return isset($this->formattedContents[$segment]);

    }

    

    /**

     * Gets all the page's formatted content segments.

     */

    public function getContentSegments()

    {

        $this->ensureContentsFormatted();

        return $this->formattedContents;

    }

    

    protected $pageData;

    /**

     * Gets the data used for rendering the page.

     */

    public function getPageData()

    {

        if ($this->pageData == null)

        {

            $this->pageData = DataBuilder::getPageData($this);

        }

        return $this->pageData;

    }

    

    protected $extraData;

    /**

     * Gets the extra data.

     */

    public function getExtraPageData()

    {

        return $this->extraData;

    }

    

    /**

     * Adds extra data to the page's data for rendering.

     */

    public function setExtraPageData(array $data)

    {

        $this->unload();

        $this->extraData = $data;

    }

    

    protected $assetUrlBaseRemap;

    /**

     * Gets the asset URL base remapping pattern.

     */

    public function getAssetUrlBaseRemap()

    {

        return $this->assetUrlBaseRemap;

    }

    

    /**

     * Sets the asset URL base remapping pattern.

     */

    public function setAssetUrlBaseRemap($remap)

    {

        $this->assetUrlBaseRemap = $remap;

    }

 

    protected $paginationDataSource;

    /**

     * Gets the pagination data source.

     */

    public function getPaginationDataSource()

    {

        return $this->paginationDataSource;

    }



    /**

     * Sets the pagination data source.

     */

    public function setPaginationDataSource($postInfos)

    {

        $this->paginationDataSource = $postInfos;

    }



    /**

     * Unloads the page.

     */

    public function unload()

    {

        $this->pageData = null;

        $this->formattedContents = null;

    }



    /**

     * Creates a new Page instance.

     */

    public function __construct(IPieCrust $pieCrust, $uri, $path, $pageType = IPage::TYPE_REGULAR, $blogKey = null, $pageKey = null, $pageNumber = 1, $date = null)

    {

        $this->pieCrust = $pieCrust;



        $this->uri = $uri;

        $this->path = $path;

        $this->type = $pageType;

        $this->blogKey = $blogKey;

        $this->key = $pageKey;

        $this->pageNumber = $pageNumber;

        $this->date = $date;

        $this->dateIsLocked = false;

        $this->pageData = null;



        $this->config = null;

        $this->contents = null;

        $this->formattedContents = null;

    }

    

    /**

     * Ensures the page has been loaded from disk.

     */

    protected function ensureConfigLoaded()

    {

        if ($this->config == null)

        {

            // Set the configuration to an empty array so that the PageLoader

            // can call 'set()' on it and assign the actual configuration.

            $this->config = new PageConfiguration($this, array(), false);



            $loader = new PageLoader($this);

            $this->contents = $loader->load();

            $this->wasCached = $loader->wasCached();

            $this->formattedContents = null;

        }

    }

    

    /**

     * Ensures the page has been formatted completely.

     */

    protected function ensureContentsFormatted()

    {

        if ($this->formattedContents == null)

        {

            $this->ensureConfigLoaded();



            $loader = new PageLoader($this);

            $this->formattedContents = $loader->formatContents($this->contents);

        }

    }

    

    /**

     * Creates a new Page instance given a fully qualified URI.

     */

    public static function createFromUri(IPieCrust $pieCrust, $uri, $useRepository = true)

    {

        if ($uri == null)

            throw new InvalidArgumentException("The given URI is null.");

        

        $uriInfo = UriParser::parseUri($pieCrust, $uri);

        if ($uriInfo == null or

            (!$uriInfo['was_path_checked'] and !is_file($uriInfo['path']))

           )

        {

            if ($uriInfo['type'] == IPage::TYPE_TAG)

                throw new PieCrustException("Tried to show posts with tag '{$uriInfo['key']}' but the special tag listing page was not found.");

            if ($uriInfo['type'] == IPage::TYPE_CATEGORY)

                throw new PieCrustException("Tried to show the posts in category '{$uriInfo['key']}' but the special category listing page was not found.");

            throw new PieCrustException('404');

        }

        

        if ($useRepository)

        {

            $pageRepository = $pieCrust->getEnvironment()->getPageRepository();

            $page = $pageRepository->getOrCreatePage(

                $uriInfo['uri'],

                $uriInfo['path'],

                $uriInfo['type'],

                $uriInfo['blogKey']

            );

            $page->setPageKey($uriInfo['key']);

            $page->setPageNumber($uriInfo['page']);

            $page->setDate($uriInfo['date']);

            return $page;

        }

        else

        {

            return new Page(

                $pieCrust,

                $uriInfo['uri'],

                $uriInfo['path'],

                $uriInfo['type'],

                $uriInfo['blogKey'],

                $uriInfo['key'],

                $uriInfo['page'],

                $uriInfo['date']

            );

        }

    }

    

    /**

     * Creates a new Page instance given a path.

     */

    public static function createFromPath(IPieCrust $pieCrust, $path, $pageType = IPage::TYPE_REGULAR, $pageNumber = 1, $blogKey = null, $pageKey = null, $date = null)

    {

        if ($path == null)

            throw new InvalidArgumentException("The given path is null.");

        if (!is_file($path))

            throw new InvalidArgumentException("The given path does not exist: " . $path);

        

        $relativePath = PieCrustHelper::getRelativePath($pieCrust, $path, true);

        $uri = UriBuilder::buildUri($pieCrust, $relativePath);

        return new Page(

                $pieCrust,

                $uri,

                $path,

                $pageType,

                $blogKey,

                $pageKey,

                $pageNumber,

                $date

            );

    }

}