File View/Widget/Image.php | Alpha Framework 3.0.0 API Documentation

  1   2   3   4   5   6   7   8   9  10  11  12  13  14  15  16  17  18  19  20  21  22  23  24  25  26  27  28  29  30  31  32  33  34  35  36  37  38  39  40  41  42  43  44  45  46  47  48  49  50  51  52  53  54  55  56  57  58  59  60  61  62  63  64  65  66  67  68  69  70  71  72  73  74  75  76  77  78  79  80  81  82  83  84  85  86  87  88  89  90  91  92  93  94  95  96  97  98  99 100 101 102 103 104 105 106 107 108 109 110 111 112 113 114 115 116 117 118 119 120 121 122 123 124 125 126 127 128 129 130 131 132 133 134 135 136 137 138 139 140 141 142 143 144 145 146 147 148 149 150 151 152 153 154 155 156 157 158 159 160 161 162 163 164 165 166 167 168 169 170 171 172 173 174 175 176 177 178 179 180 181 182 183 184 185 186 187 188 189 190 191 192 193 194 195 196 197 198 199 200 201 202 203 204 205 206 207 208 209 210 211 212 213 214 215 216 217 218 219 220 221 222 223 224 225 226 227 228 229 230 231 232 233 234 235 236 237 238 239 240 241 242 243 244 245 246 247 248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282 283 284 285 286 287 288 289 290 291 292 293 294 295 296 297 298 299 300 301 302 303 304 305 306 307 308 309 310 311 312 313 314 315 316 317 318 319 320 321 322 323 324 325 326 327 328 329 330 331 332 333 334 335 336 337 338 339 340 341 342 343 344 345 346 347 348 349 350 351 352 353 354 355 356 357 358 359 360 361 362 363 364 365 366 367 368 369 370 371 372 373 374 375 376 377 378 379 380 381 382 383 384 385 386 387 388 389 390 391 392 393 394 395 396 397 398 399 400 401 402 403 404 405 406 407 408 409 410 411 412 413 414 415 416 417 418 419 420 421 422 423 424 425 426 427 428 429 430 431 432 433 434 435 436 437 438 439 440

<?php

namespace Alpha\View\Widget;

use Alpha\Util\Logging\Logger;
use Alpha\Util\Config\ConfigProvider;
use Alpha\Model\Type\Integer;
use Alpha\Model\Type\Enum;
use Alpha\Model\Type\Boolean;
use Alpha\Model\Type\Double;
use Alpha\Exception\IllegalArguementException;
use Alpha\Controller\Controller;
use Alpha\Controller\Front\FrontController;

/**
 * A widget that can generate an image which is scaled to the screen resolution of the
 * user, and can be made secured to prevent hot-linking from remote sites.  Note that by
 * default, a jpg file will be returned (the source file can be jpg, png, or gif).
 *
 * @since 1.0
 *
 * @author John Collins <dev@alphaframework.org>
 * @license http://www.opensource.org/licenses/bsd-license.php The BSD License
 * @copyright Copyright (c) 2018, John Collins (founder of Alpha Framework).
 * All rights reserved.
 *
 * <pre>
 * Redistribution and use in source and binary forms, with or
 * without modification, are permitted provided that the
 * following conditions are met:
 *
 * * Redistributions of source code must retain the above
 *   copyright notice, this list of conditions and the
 *   following disclaimer.
 * * Redistributions in binary form must reproduce the above
 *   copyright notice, this list of conditions and the
 *   following disclaimer in the documentation and/or other
 *   materials provided with the distribution.
 * * Neither the name of the Alpha Framework nor the names
 *   of its contributors may be used to endorse or promote
 *   products derived from this software without specific
 *   prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND
 * CONTRIBUTORS "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES,
 * INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
 * DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDER OR
 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
 * SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
 * LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
 * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE
 * OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
 * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 * </pre>
 */
class Image
{
    /**
     * The title of the image for alt text (optional).
     *
     * @var string
     *
     * @since 1.0
     */
    private $title;

    /**
     * The absolute path to the source image.
     *
     * @var string
     *
     * @since 1.0
     */
    private $source;

    /**
     * The width of the image (can differ from the source file when scale=true).
     *
     * @var \Alpha\Model\Type\Integer
     *
     * @since 1.0
     */
    private $width;

    /**
     * The height of the image (can differ from the source file when scale=true).
     *
     * @var \Alpha\Model\Type\Integer
     *
     * @since 1.0
     */
    private $height;

    /**
     * The file type of the source image (gif, jpg, or png supported).
     *
     * @var \Alpha\Model\Type\Enum
     *
     * @since 1.0
     */
    private $sourceType;

    /**
     * The quality of the jpg image generated (0.00 to 1.00, 0.75 by default).
     *
     * @var \Alpha\Model\Type\Double
     *
     * @since 1.0
     */
    private $quality;

    /**
     * Flag to determine if the image will scale to match the target resolution (false
     * by default).
     *
     * @var \Alpha\Model\Type\Boolean
     *
     * @since 1.0
     */
    private $scale;

    /**
     * Flag to determine if the link to the image will change every 24hrs, making hot-linking
     * to the image difficult (false by default).
     *
     * @var \Alpha\Model\Type\Boolean
     *
     * @since 1.0
     */
    private $secure;

    /**
     * The auto-generated name of the cache file for the image.
     *
     * @var string
     *
     * @since 1.0
     */
    private $filename;

    /**
     * Trace logger.
     *
     * @var \Alpha\Util\Logging\Logger
     *
     * @since 1.0
     */
    private static $logger = null;

    /**
     * The constructor.
     *
     * @param string $source
     * @param $width
     * @param $height
     * @param $sourceType
     * @param $quality
     * @param $scale
     *
     * @throws \Alpha\Exception\IllegalArguementException
     *
     * @since 1.0
     */
    public function __construct($source, $width, $height, $sourceType, $quality = 0.75, $scale = false, $secure = false)
    {
        self::$logger = new Logger('Image');
        self::$logger->debug('>>__construct(source=['.$source.'], width=['.$width.'], height=['.$height.'], sourceType=['.$sourceType.'], quality=['.$quality.'], scale=['.$scale.'], secure=['.$secure.'])');

        if (file_exists($source)) {
            $this->source = $source;
        } else {
            throw new IllegalArguementException('The source file for the Image widget ['.$source.'] cannot be found!');
        }

        $this->sourceType = new Enum();
        $this->sourceType->setOptions(array('jpg', 'png', 'gif'));
        $this->sourceType->setValue($sourceType);

        if ($quality < 0.0 || $quality > 1.0) {
            throw new IllegalArguementException('The quality setting of ['.$quality.'] is outside of the allowable range of 0.0 to 1.0');
        }

        $this->quality = new Double($quality);
        $this->scale = new Boolean($scale);
        $this->secure = new Boolean($secure);

        $this->width = new Integer($width);
        $this->height = new Integer($height);

        $this->setFilename();

        self::$logger->debug('<<__construct');
    }

    /**
     * Renders the HTML <img> tag to the ViewImage controller, with all of the correct params to render the source
     * image in the desired resolution.
     *
     * @param $altText Set this value to render alternate text as part of the HTML link (defaults to no alternate text)
     *
     * @return string
     *
     * @since 1.0
     */
    public function renderHTMLLink($altText = '')
    {
        $config = ConfigProvider::getInstance();

        $url = '';

        if ($this->secure->getBooleanValue()) {
            $params = Controller::generateSecurityFields();

            $url = FrontController::generateSecureURL('act=Alpha\Controller\ImageController&source='.$this->source.'&width='.$this->width->getValue().'&height='.$this->height->getValue().'&type='.$this->sourceType->getValue().'&quality='.$this->quality->getValue().'&scale='.$this->scale->getValue().'&secure='.$this->secure->getValue().'&var1='.$params[0].'&var2='.$params[1]);
        } else {
            $url = FrontController::generateSecureURL('act=Alpha\Controller\ImageController&source='.$this->source.'&width='.$this->width->getValue().'&height='.$this->height->getValue().'&type='.$this->sourceType->getValue().'&quality='.$this->quality->getValue().'&scale='.$this->scale->getValue().'&secure='.$this->secure->getValue());
        }

        return '<img src="'.$url.'"'.(empty($altText) ? '' : ' alt="'.$altText.'"').($config->get('cms.images.widget.bootstrap.responsive') ? ' class="img-responsive"' : '').'/>';
    }

    /**
     * Setter for the filename, which also creates a sub-directory under /cache for images when required.
     *
     * @since 1.0
     *
     * @throws \Alpha\Exception\AlphaException
     */
    private function setFilename()
    {
        $config = ConfigProvider::getInstance();

        if (!strpos($this->source, 'attachments/article_')) {
            // checking to see if we will write a jpg or png to the cache
            if ($this->sourceType->getValue() == 'png' && $config->get('cms.images.perserve.png')) {
                $this->filename = $config->get('app.file.store.dir').'cache/images/'.basename($this->source, '.'.$this->sourceType->getValue()).'_'.$this->width->getValue().'x'.$this->height->getValue().'.png';
            } else {
                $this->filename = $config->get('app.file.store.dir').'cache/images/'.basename($this->source, '.'.$this->sourceType->getValue()).'_'.$this->width->getValue().'x'.$this->height->getValue().'.jpg';
            }
        } else {
            // make a cache dir for the article
            $cacheDir = $config->get('app.file.store.dir').'cache/images/article_'.mb_substr($this->source, mb_strpos($this->source, 'attachments/article_')+20, 11);
            if (!file_exists($cacheDir)) {
                $success = mkdir($cacheDir);

                if (!$success) {
                    throw new AlphaException('Unable to create the folder '.$cacheDir.' for the cache image, source file is '.$this->source);
                }

                // ...and set write permissions on the folder
                $success = chmod($cacheDir, 0777);

                if (!$success) {
                    throw new AlphaException('Unable to set write permissions on the folder ['.$cacheDir.'].');
                }
            }

            // now set the filename to include the new cache directory
            if ($this->sourceType->getValue() == 'png' && $config->get('cms.images.perserve.png')) {
                $this->filename = $cacheDir.'/'.basename($this->source, '.'.$this->sourceType->getValue()).'_'.$this->width->getValue().'x'.$this->height->getValue().'.png';
            } else {
                $this->filename = $cacheDir.'/'.basename($this->source, '.'.$this->sourceType->getValue()).'_'.$this->width->getValue().'x'.$this->height->getValue().'.jpg';
            }
        }

        self::$logger->debug('Image filename is ['.$this->filename.']');
    }

    /**
     * Gets the auto-generated filename for the image in the /cache directory.
     *
     * @since 1.0
     */
    public function getFilename()
    {
        return $this->filename;
    }

    /**
     * Renders the actual binary image using GD library calls.
     *
     * @param $screenSize The optional size of the target screen to scale to in the format [X-pixels]x[Y-pixels]
     *
     * @since 1.0
     */
    public function renderImage($screenSize = null)
    {
        $config = ConfigProvider::getInstance();

        // if scaled, we need to compute the target image size
        if ($this->scale->getBooleanValue() && $screenSize !== null) {
            $originalScreenResolution = explode('x', $config->get('sysCMSImagesWidgetScreenResolution'));
            $originalScreenX = $originalScreenResolution[0];
            $originalScreenY = $originalScreenResolution[1];

            $targetScreenResolution = explode('x', $screenSize);
            $targetScreenX = $targetScreenResolution[0];
            $targetScreenY = $targetScreenResolution[1];

            // calculate the new units we will scale by
            $xu = $targetScreenX/$originalScreenX;
            $yu = $targetScreenY/$originalScreenY;

            $this->width = new Integer(intval($this->width->getValue()*$xu));
            $this->height = new Integer(intval($this->height->getValue()*$yu));

            // need to update the cache filename as the dimensions have changed
            $this->setFilename();
        }

        // check the image cache first before we proceed
        if ($this->checkCache()) {
            $this->loadCache();
        } else {
            // now get the old image
            switch ($this->sourceType->getValue()) {
                case 'gif':
                    $oldImage = imagecreatefromgif($this->source);
                break;
                case 'jpg':
                    $oldImage = imagecreatefromjpeg($this->source);
                break;
                default:
                    $oldImage = imagecreatefrompng($this->source);
            }

            if (!$oldImage) {
                $im = imagecreatetruecolor($this->width->getValue(), $this->height->getValue());
                $bgc = imagecolorallocate($im, 255, 255, 255);
                $tc = imagecolorallocate($im, 0, 0, 0);
                imagefilledrectangle($im, 0, 0, $this->width->getValue(), $this->height->getValue(), $bgc);

                imagestring($im, 1, 5, 5, "Error loading $this->source", $tc);
                if ($this->sourceType->getValue() == 'png' && $config->get('cms.images.perserve.png')) {
                    imagepng($im);
                } else {
                    imagejpeg($im);
                }
                imagedestroy($im);
            } else {
                // the dimensions of the source image
                $oldWidth = imagesx($oldImage);
                $oldHeight = imagesy($oldImage);

                // now create the new image
                $newImage = imagecreatetruecolor($this->width->getValue(), $this->height->getValue());

                // set a transparent background for PNGs
                if ($this->sourceType->getValue() == 'png' && $config->get('cms.images.perserve.png')) {
                    // Turn off transparency blending (temporarily)
                    imagealphablending($newImage, false);

                    // Create a new transparent color for image
                    $color = imagecolorallocatealpha($newImage, 255, 0, 0, 0);

                    // Completely fill the background of the new image with allocated color.
                    imagefill($newImage, 0, 0, $color);

                    // Restore transparency blending
                    imagesavealpha($newImage, true);
                }
                // copy the old image to the new image (in memory, not the file!)
                imagecopyresampled($newImage, $oldImage, 0, 0, 0, 0, $this->width->getValue(), $this->height->getValue(), $oldWidth, $oldHeight);

                if ($this->sourceType->getValue() == 'png' && $config->get('cms.images.perserve.png')) {
                    imagepng($newImage);
                } else {
                    imagejpeg($newImage, null, 100*$this->quality->getValue());
                }

                $this->cache($newImage);
                imagedestroy($oldImage);
                imagedestroy($newImage);
            }
        }
    }

    /**
     * Caches the image to the cache directory.
     *
     * @param image $image the binary GD image stream to save
     *
     * @since 1.0
     */
    private function cache($image)
    {
        $config = ConfigProvider::getInstance();

        if ($this->sourceType->getValue() == 'png' && $config->get('cms.images.perserve.png')) {
            imagepng($image, $this->filename);
        } else {
            imagejpeg($image, $this->filename, 100*$this->quality->getValue());
        }
    }

    /**
     * Used to check the image cache for the image jpeg cache file.
     *
     * @return bool
     *
     * @since 1.0
     */
    private function checkCache()
    {
        return file_exists($this->filename);
    }

    /**
     * Method to load the content of the image cache file to the standard output stream (the browser).
     *
     * @since 1.0
     */
    private function loadCache()
    {
        readfile($this->filename);
    }

    /**
     * Converts a URL for an image to a relative file system path for the image, assuming it is
     * hosted on the same server as the application.
     *
     * @param string $imgURL
     *
     * @return string the path of the image
     *
     * @since 1.0
     */
    public static function convertImageURLToPath($imgURL)
    {
        $config = ConfigProvider::getInstance();

        $imgPath = str_replace($config->get('app.url').'/', '', $imgURL);

        return $imgPath;
    }
}

Namespaces

Classes

Interfaces

Exceptions