Charcoal\View\AbstractLoader

Complexity

Total Complexity

34

Size/Duplication

Total Lines	287
Duplicated Lines	0 %

Coupling/Cohesion

Components	1
Dependencies	1

Importance

Changes

0

15 Methods

Rating	Name	Duplication	Size	Complexity
	filenameFromIdent()	0	1	?
A	__construct()	0	6	1
A	load()	0	22	5
A	dynamicTemplate()	0	14	3
A	setDynamicTemplate()	0	21	4
A	removeDynamicTemplate()	0	10	2
A	clearDynamicTemplates()	0	4	1
A	basePath()	0	4	1
A	setBasePath()	0	11	2
A	paths()	0	4	1
A	setPaths()	0	10	2
A	addPath()	0	6	1
A	resolvePath()	0	16	4
A	isTemplateString()	0	4	1
B	findTemplateFile()	0	29	6

<?php

namespace Charcoal\View;

use InvalidArgumentException;

// From PSR-3
use Psr\Log\LoggerAwareInterface;
use Psr\Log\LoggerAwareTrait;

// From 'charcoal-view'
use Charcoal\View\LoaderInterface;

/**
 * Base Template Loader
 *
 * Finds a template file in a collection of directory paths.
 */
abstract class AbstractLoader implements
    LoggerAwareInterface,
    LoaderInterface
{
    use LoggerAwareTrait;

    /**
     * @var string
     */
    private $basePath = '';

    /**
     * @var string[]
     */
    private $paths = [];

    /**
     * @var array
     */
    private $dynamicTemplates = [];

    /**
     * The cache of searched template files.
     *
     * @var array
     */
    private $fileCache = [];

    /**
     * Default constructor, if none is provided by the concrete class implementations.
     *
     * ## Required dependencies
     * - `logger` A PSR-3 logger
     *
     * @param array $data The class dependencies map.
     */
    public function __construct(array $data = null)
    {
        $this->setLogger($data['logger']);
        $this->setBasePath($data['base_path']);
        $this->setPaths($data['paths']);
    }

    /**
     * Load a template content
     *
     * @param  string $ident The template ident to load and render.
     * @throws InvalidArgumentException If the dynamic template identifier is not a string.
     * @return string
     */
    public function load($ident)
    {
        // Handle dynamic template
        if (substr($ident, 0, 1) === '$') {
            $ident = $this->dynamicTemplate(substr($ident, 1));
        }

        /**
         * Prevents the loader from passing a proper template through further
         * procedures meant for a template identifier.
         */
        if ($this->isTemplateString($ident)) {
            return $ident;
        }

        $file = $this->findTemplateFile($ident);
        if ($file === null || $file === '') {
            return $ident;
        }

        return file_get_contents($file);
    }

    /**
     * @param  string $varName The name of the variable to get template ident from.
     * @throws InvalidArgumentException If the var name is not a string.
     * @return string
     */
    public function dynamicTemplate($varName)
    {
        if (!is_string($varName)) {
            throw new InvalidArgumentException(
                'Can not get dynamic template: var name is not a string.'
            );
        }

        if (!isset($this->dynamicTemplates[$varName])) {
            return '';
        }

        return $this->dynamicTemplates[$varName];
    }

    /**
     * @param  string      $varName       The name of the variable to set this template unto.
     * @param  string|null $templateIdent The "dynamic template" to set or NULL to clear.
     * @throws InvalidArgumentException If var name is not a string
     *     or if the template is not a string (and not null).
     * @return void
     */
    public function setDynamicTemplate($varName, $templateIdent)
    {
        if (!is_string($varName)) {
            throw new InvalidArgumentException(
                'Can not set dynamic template: var name is not a string.'
            );
        }

        if ($templateIdent === null) {
            $this->removeDynamicTemplate($varName);
            return;
        }

        if (!is_string($templateIdent)) {
            throw new InvalidArgumentException(
                'Can not set dynamic template. Must be a a string, or null.'
            );
        }

        $this->dynamicTemplates[$varName] = $templateIdent;
    }

    /**
     * @param  string $varName The name of the variable to remove.
     * @throws InvalidArgumentException If var name is not a string.
     * @return void
     */
    public function removeDynamicTemplate($varName)
    {
        if (!is_string($varName)) {
            throw new InvalidArgumentException(
                'Can not set dynamic template: var name is not a string.'
            );
        }

        unset($this->dynamicTemplates[$varName]);
    }

    /**
     * @return void
     */
    public function clearDynamicTemplates()
    {
        $this->dynamicTemplates = [];
    }

    /**
     * @return string
     */
    protected function basePath()
    {
        return $this->basePath;
    }

    /**
     * @param  string $basePath The base path to set.
     * @throws InvalidArgumentException If the base path parameter is not a string.
     * @return LoaderInterface Chainable
     */
    private function setBasePath($basePath)
    {
        if (!is_string($basePath)) {
            throw new InvalidArgumentException(
                'Base path must be a string'
            );
        }
        $basePath = realpath($basePath);
        $this->basePath = rtrim($basePath, '/\\').DIRECTORY_SEPARATOR;
        return $this;
    }

    /**
     * @return string[]
     */
    protected function paths()
    {
        return $this->paths;
    }

    /**
     * @param  string[] $paths The list of path to add.
     * @return LoaderInterface Chainable
     */
    private function setPaths(array $paths)
    {
        $this->paths = [];

        foreach ($paths as $path) {
            $this->addPath($path);
        }

        return $this;
    }

    /**
     * @param  string $path The path to add to the load.
     * @return LoaderInterface Chainable
     */
    private function addPath($path)
    {
        $this->paths[] = $this->resolvePath($path);

        return $this;
    }

    /**
     * @param  string $path The path to resolve.
     * @throws InvalidArgumentException If the path argument is not a string.
     * @return string
     */
    private function resolvePath($path)
    {
        if (!is_string($path)) {
            throw new InvalidArgumentException(
                'Path needs to be a string'
            );
        }

        $basePath = $this->basePath();
        $path = rtrim($path, '/\\').DIRECTORY_SEPARATOR;
        if ($basePath && strpos($path, $basePath) === false) {
            $path = $basePath.$path;
        }

        return $path;
    }

    /**
     * Determine if the variable is a template literal.
     *
     * This method looks for any line-breaks in the given string,
     * which a file path would not allow.
     *
     * @param  string $ident The template being evaluated.
     * @return boolean Returns TRUE if the given value is most likely the template contents
     *     as opposed to a template identifier (file path).
     */
    protected function isTemplateString($ident)
    {
        return strpos($ident, PHP_EOL) !== false;
    }

    /**
     * Get the template file (full path + filename) to load from an ident.
     *
     * This method first generates the filename for an identifier and search for it in all of the loader's paths.
     *
     * @param  string $ident The template identifier to load.
     * @throws InvalidArgumentException If the template ident is not a string.
     * @return string|null The full path + filename of the found template. NULL if nothing was found.
     */
    protected function findTemplateFile($ident)
    {
        if (!is_string($ident)) {
            throw new InvalidArgumentException(sprintf(
                'Template ident must be a string, received %s',
                is_object($ident) ? get_class($ident) : gettype($ident)
            ));
        }

        $key = hash('md5', $ident);

        if (array_key_exists($key, $this->fileCache)) {
            return $this->fileCache[$key];
        }

        $filename    = $this->filenameFromIdent($ident);
        $searchPaths = $this->paths();
        foreach ($searchPaths as $searchPath) {
            $filepath = realpath($searchPath).'/'.strtolower($filename);
            if (file_exists($filepath)) {
                $this->fileCache[$key] = $filepath;
                return $filepath;
            }
        }

        $filepath = null;
        $this->fileCache[$key] = $filepath;
        return $filepath;
    }

    /**
     * @param  string $ident The template identifier to convert to a filename.
     * @return string
     */
    abstract protected function filenameFromIdent($ident);
}