picocms/lib/PicoTwigExtension.php

488 lines
19 KiB
PHP

<?php
/**
* This file is part of Pico. It's copyrighted by the contributors recorded
* in the version control history of the file, available from the following
* original location:
*
* <https://github.com/picocms/Pico/blob/master/lib/PicoTwigExtension.php>
*
* SPDX-License-Identifier: MIT
* License-Filename: LICENSE
*/
/**
* Pico's Twig extension to implement additional filters
*
* @author Daniel Rudolf
* @link http://picocms.org
* @license http://opensource.org/licenses/MIT The MIT License
* @version 2.1
*/
class PicoTwigExtension extends Twig_Extension
{
/**
* Current instance of Pico
*
* @see PicoTwigExtension::getPico()
* @var Pico
*/
private $pico;
/**
* Constructs a new instance of this Twig extension
*
* @param Pico $pico current instance of Pico
*/
public function __construct(Pico $pico)
{
$this->pico = $pico;
}
/**
* Returns the extensions instance of Pico
*
* @see Pico
*
* @return Pico the extension's instance of Pico
*/
public function getPico()
{
return $this->pico;
}
/**
* Returns the name of the extension
*
* @see Twig_ExtensionInterface::getName()
*
* @return string the extension name
*/
public function getName()
{
return 'PicoTwigExtension';
}
/**
* Returns a list of Pico-specific Twig filters
*
* @see Twig_ExtensionInterface::getFilters()
*
* @return Twig_SimpleFilter[] array of Pico's Twig filters
*/
public function getFilters()
{
return array(
'markdown' => new Twig_SimpleFilter(
'markdown',
array($this, 'markdownFilter'),
array('is_safe' => array('html'))
),
'map' => new Twig_SimpleFilter('map', array($this, 'mapFilter')),
'sort_by' => new Twig_SimpleFilter('sort_by', array($this, 'sortByFilter')),
'link' => new Twig_SimpleFilter('link', array($this->pico, 'getPageUrl')),
'url' => new Twig_SimpleFilter('url', array($this->pico, 'substituteUrl'))
);
}
/**
* Returns a list of Pico-specific Twig functions
*
* @see Twig_ExtensionInterface::getFunctions()
*
* @return Twig_SimpleFunction[] array of Pico's Twig functions
*/
public function getFunctions()
{
return array(
'url_param' => new Twig_SimpleFunction('url_param', array($this, 'urlParamFunction')),
'form_param' => new Twig_SimpleFunction('form_param', array($this, 'formParamFunction')),
'pages' => new Twig_SimpleFunction('pages', array($this, 'pagesFunction'))
);
}
/**
* Parses a markdown string to HTML
*
* This method is registered as the Twig `markdown` filter. You can use it
* to e.g. parse a meta variable (`{{ meta.description|markdown }}`).
* Don't use it to parse the contents of a page, use the `content` filter
* instead, what ensures the proper preparation of the contents.
*
* @see Pico::substituteFileContent()
* @see Pico::parseFileContent()
*
* @param string $markdown markdown to parse
* @param array $meta meta data to use for %meta.*% replacement
* @param bool $singleLine whether to parse just a single line of markup
*
* @return string parsed HTML
*/
public function markdownFilter($markdown, array $meta = array(), $singleLine = false)
{
$markdown = $this->getPico()->substituteFileContent($markdown, $meta);
return $this->getPico()->parseFileContent($markdown, $singleLine);
}
/**
* Returns a array with the values of the given key or key path
*
* This method is registered as the Twig `map` filter. You can use this
* filter to e.g. get all page titles (`{{ pages|map("title") }}`).
*
* @param array|Traversable $var variable to map
* @param mixed $mapKeyPath key to map; either a scalar or a
* array interpreted as key path (i.e. ['foo', 'bar'] will return all
* $item['foo']['bar'] values)
*
* @return array mapped values
*
* @throws Twig_Error_Runtime
*/
public function mapFilter($var, $mapKeyPath)
{
if (!is_array($var) && (!is_object($var) || !($var instanceof Traversable))) {
throw new Twig_Error_Runtime(sprintf(
'The map filter only works with arrays or "Traversable", got "%s"',
is_object($var) ? get_class($var) : gettype($var)
));
}
$result = array();
foreach ($var as $key => $value) {
$mapValue = $this->getKeyOfVar($value, $mapKeyPath);
$result[$key] = ($mapValue !== null) ? $mapValue : $value;
}
return $result;
}
/**
* Sorts an array by one of its keys or a arbitrary deep sub-key
*
* This method is registered as the Twig `sort_by` filter. You can use this
* filter to e.g. sort the pages array by a arbitrary meta value. Calling
* `{{ pages|sort_by([ "meta", "nav" ]) }}` returns all pages sorted by the
* meta value `nav`. The sorting algorithm will never assume equality of
* two values, it will then fall back to the original order. The result is
* always sorted in ascending order, apply Twigs `reverse` filter to
* achieve a descending order.
*
* @param array|Traversable $var variable to sort
* @param mixed $sortKeyPath key to use for sorting; either
* a scalar or a array interpreted as key path (i.e. ['foo', 'bar']
* will sort $var by $item['foo']['bar'])
* @param string $fallback specify what to do with items
* which don't contain the specified sort key; use "bottom" (default)
* to move these items to the end of the sorted array, "top" to rank
* them first, "keep" to keep the original order, or "remove" to remove
* these items
*
* @return array sorted array
*
* @throws Twig_Error_Runtime
*/
public function sortByFilter($var, $sortKeyPath, $fallback = 'bottom')
{
if (is_object($var) && ($var instanceof Traversable)) {
$var = iterator_to_array($var, true);
} elseif (!is_array($var)) {
throw new Twig_Error_Runtime(sprintf(
'The sort_by filter only works with arrays or "Traversable", got "%s"',
is_object($var) ? get_class($var) : gettype($var)
));
}
if (($fallback !== 'top') && ($fallback !== 'bottom') && ($fallback !== 'keep') && ($fallback !== "remove")) {
throw new Twig_Error_Runtime(
'The sort_by filter only supports the "top", "bottom", "keep" and "remove" fallbacks'
);
}
$twigExtension = $this;
$varKeys = array_keys($var);
$removeItems = array();
uksort($var, function ($a, $b) use ($twigExtension, $var, $varKeys, $sortKeyPath, $fallback, &$removeItems) {
$aSortValue = $twigExtension->getKeyOfVar($var[$a], $sortKeyPath);
$aSortValueNull = ($aSortValue === null);
$bSortValue = $twigExtension->getKeyOfVar($var[$b], $sortKeyPath);
$bSortValueNull = ($bSortValue === null);
if (($fallback === 'remove') && ($aSortValueNull || $bSortValueNull)) {
if ($aSortValueNull) {
$removeItems[$a] = $var[$a];
}
if ($bSortValueNull) {
$removeItems[$b] = $var[$b];
}
return ($aSortValueNull - $bSortValueNull);
} elseif ($aSortValueNull xor $bSortValueNull) {
if ($fallback === 'top') {
return ($aSortValueNull - $bSortValueNull) * -1;
} elseif ($fallback === 'bottom') {
return ($aSortValueNull - $bSortValueNull);
}
} elseif (!$aSortValueNull && !$bSortValueNull) {
if ($aSortValue != $bSortValue) {
return ($aSortValue > $bSortValue) ? 1 : -1;
}
}
// never assume equality; fallback to original order
$aIndex = array_search($a, $varKeys);
$bIndex = array_search($b, $varKeys);
return ($aIndex > $bIndex) ? 1 : -1;
});
if ($removeItems) {
$var = array_diff_key($var, $removeItems);
}
return $var;
}
/**
* Returns the value of a variable item specified by a scalar key or a
* arbitrary deep sub-key using a key path
*
* @param array|Traversable|ArrayAccess|object $var base variable
* @param mixed $keyPath scalar key or a
* array interpreted as key path (when passing e.g. ['foo', 'bar'],
* the method will return $var['foo']['bar']) specifying the value
*
* @return mixed the requested value or NULL when the given key or key path
* didn't match
*/
public static function getKeyOfVar($var, $keyPath)
{
if (!$keyPath) {
return null;
} elseif (!is_array($keyPath)) {
$keyPath = array($keyPath);
}
foreach ($keyPath as $key) {
if (is_object($var)) {
if ($var instanceof ArrayAccess) {
// use ArrayAccess, see below
} elseif ($var instanceof Traversable) {
$var = iterator_to_array($var);
} elseif (isset($var->{$key})) {
$var = $var->{$key};
continue;
} elseif (is_callable(array($var, 'get' . ucfirst($key)))) {
try {
$var = call_user_func(array($var, 'get' . ucfirst($key)));
continue;
} catch (BadMethodCallException $e) {
return null;
}
} else {
return null;
}
} elseif (!is_array($var)) {
return null;
}
if (isset($var[$key])) {
$var = $var[$key];
continue;
}
return null;
}
return $var;
}
/**
* Filters a URL GET parameter with a specified filter
*
* The Twig function disallows the use of the `callback` filter.
*
* @see Pico::getUrlParameter()
*
* @param string $name name of the URL GET parameter
* to filter
* @param int|string $filter the filter to apply
* @param mixed|array $options either a associative options
* array to be used by the filter or a scalar default value
* @param int|string|int[]|string[] $flags flags and flag strings to be
* used by the filter
*
* @return mixed either the filtered data, FALSE if the filter fails, or
* NULL if the URL GET parameter doesn't exist and no default value is
* given
*/
public function urlParamFunction($name, $filter = '', $options = null, $flags = null)
{
$filter = $filter ? (is_string($filter) ? filter_id($filter) : (int) $filter) : false;
if (!$filter || ($filter === FILTER_CALLBACK)) {
return false;
}
return $this->pico->getUrlParameter($name, $filter, $options, $flags);
}
/**
* Filters a HTTP POST parameter with a specified filter
*
* The Twig function disallows the use of the `callback` filter.
*
* @see Pico::getFormParameter()
*
* @param string $name name of the HTTP POST
* parameter to filter
* @param int|string $filter the filter to apply
* @param mixed|array $options either a associative options
* array to be used by the filter or a scalar default value
* @param int|string|int[]|string[] $flags flags and flag strings to be
* used by the filter
*
* @return mixed either the filtered data, FALSE if the filter fails, or
* NULL if the HTTP POST parameter doesn't exist and no default value
* is given
*/
public function formParamFunction($name, $filter = '', $options = null, $flags = null)
{
$filter = $filter ? (is_string($filter) ? filter_id($filter) : (int) $filter) : false;
if (!$filter || ($filter === FILTER_CALLBACK)) {
return false;
}
return $this->pico->getFormParameter($name, $filter, $options, $flags);
}
/**
* Returns all pages within a particular branch of Pico's page tree
*
* This function should be used most of the time when dealing with Pico's
* pages array, as it allows one to easily traverse Pico's pages tree
* ({@see Pico::getPageTree()}) to retrieve a subset of Pico's pages array
* in a very convenient and performant way.
*
* The function's default parameters are `$start = ""`, `$depth = 0`,
* `$depthOffset = 0` and `$offset = 1`. A positive `$offset` is equivalent
* to `$depth = $depth + $offset`, `$depthOffset = $depthOffset + $offset`
* and `$offset = 0`.
*
* Consequently the default `$start = ""`, `$depth = 0`, `$depthOffset = 0`
* and `$offset = 1` is equivalent to `$depth = 1`, `$depthOffset = 1` and
* `$offset = 0`. `$start = ""` instruct the function to start from the
* root node (i.e. the node of Pico's main index page at `index.md`).
* `$depth` tells the function what pages to return. In this example,
* `$depth = 1` matches the start node (i.e. the zeroth generation) and all
* its descendant pages until the first generation (i.e. the start node's
* children). `$depthOffset` instructs the function to exclude some of the
* older generations. `$depthOffset = 1` specifically tells the function
* to exclude the zeroth generation, so that the function returns all of
* Pico's main index page's direct child pages (like `sub/index.md` and
* `page.md`, but not `sub/page.md`) only.
*
* Passing `$depthOffset = -1` only is the same as passing `$start = ""`,
* `$depth = 1`, `$depthOffset = 0` and `$offset = 0`. The only difference
* is that `$depthOffset` won't exclude the zeroth generation, so that the
* function returns Pico's main index page as well as all of its direct
* child pages.
*
* Passing `$depth = 0`, `$depthOffset = -2` and `$offset = 2` is the same
* as passing `$depth = 2`, `$depthOffset = 0` and `$offset = 0`. Both will
* return the zeroth, first and second generation of pages. For Pico's main
* index page this would be `index.md` (0th gen), `sub/index.md` (1st gen),
* `sub/page.md` (2nd gen) and `page.md` (1st gen). If you want to return
* 2nd gen pages only, pass `$offset = 2` only (with implicit `$depth = 0`
* and `$depthOffset = 0` it's the same as `$depth = 2`, `$depthOffset = 2`
* and `$offset = 0`).
*
* Instead of an integer you can also pass `$depth = null`. This is the
* same as passing an infinitely large number as `$depth`, so that this
* function simply returns all descendant pages. Consequently passing
* `$start = ""`, `$depth = null`, `$depthOffset = 0` and `$offset = 0`
* returns Pico's full pages array.
*
* If `$depth` is negative after taking `$offset` into consideration, the
* function will throw a {@see Twig_Error_Runtime} exception, since this
* would simply make no sense and is likely an error. Passing a negative
* `$depthOffset` is equivalent to passing `$depthOffset = 0`.
*
* But what about a negative `$offset`? Passing `$offset = -1` instructs
* the function not to start from the given `$start` node, but its parent
* node. Consequently `$offset = -2` instructs the function to use the
* `$start` node's grandparent node. Obviously this won't make any sense
* for Pico's root node, but just image `$start = "sub/index"`. Passing
* this together with `$offset = -1` is equivalent to `$start = ""` and
* `$offset = 0`.
*
* @param string $start name of the node to start from
* @param int|null $depth return pages until the given maximum depth;
* pass NULL to return all descendant pages; defaults to 0
* @param int $depthOffset start returning pages from the given
* minimum depth; defaults to 0
* @param int $offset ascend (positive) or descend (negative) the
* given number of branches before returning pages; defaults to 1
*
* @return array[] the data of the matched pages
*
* @throws Twig_Error_Runtime
*/
public function pagesFunction($start = '', $depth = 0, $depthOffset = 0, $offset = 1)
{
$start = (string) $start;
if (basename($start) === 'index') {
$start = dirname($start);
}
for (; $offset < 0; $offset++) {
if (in_array($start, array('', '.', '/'), true)) {
$offset = 0;
break;
}
$start = dirname($start);
}
$depth = ($depth !== null) ? $depth + $offset : null;
$depthOffset = $depthOffset + $offset;
if (($depth !== null) && ($depth < 0)) {
throw new Twig_Error_Runtime('The pages function doesn\'t support negative depths');
}
$pageTree = $this->getPico()->getPageTree();
if (in_array($start, array('', '.', '/'), true)) {
if (($depth === null) && ($depthOffset <= 0)) {
return $this->getPico()->getPages();
}
$startNode = isset($pageTree['']['/']) ? $pageTree['']['/'] : null;
} else {
$branch = dirname($start);
$branch = ($branch !== '.') ? $branch : '/';
$node = (($branch !== '/') ? $branch . '/' : '') . basename($start);
$startNode = isset($pageTree[$branch][$node]) ? $pageTree[$branch][$node] : null;
}
if (!$startNode) {
return array();
}
$getPagesClosure = function ($nodes, $depth, $depthOffset) use (&$getPagesClosure) {
$pages = array();
foreach ($nodes as $node) {
if (isset($node['page']) && ($depthOffset <= 0)) {
$pages[$node['page']['id']] = &$node['page'];
}
if (isset($node['children']) && ($depth > 0)) {
$pages += $getPagesClosure($node['children'], $depth - 1, $depthOffset - 1);
}
}
return $pages;
};
return $getPagesClosure(
array($startNode),
($depth !== null) ? $depth : INF,
$depthOffset
);
}
}