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Diffstat (limited to 'app/User/Avatar/LetterAvatarProvider.php')
| -rw-r--r-- | app/User/Avatar/LetterAvatarProvider.php | 169 |
1 files changed, 169 insertions, 0 deletions
diff --git a/app/User/Avatar/LetterAvatarProvider.php b/app/User/Avatar/LetterAvatarProvider.php new file mode 100644 index 00000000..81c4586d --- /dev/null +++ b/app/User/Avatar/LetterAvatarProvider.php @@ -0,0 +1,169 @@ +<?php + +namespace Kanboard\User\Avatar; + +use Kanboard\Core\Base; +use Kanboard\Core\User\Avatar\AvatarProviderInterface; + +/** + * Letter Avatar Provider + * + * The color hash algorithm is backported from the Javascript library color-hash + * Source: https://github.com/zenozeng/color-hash + * Author: Zeno Zeng (MIT License) + * + * @package avatar + * @author Frederic Guillot + */ +class LetterAvatarProvider extends Base implements AvatarProviderInterface +{ + protected $lightness = array(0.35, 0.5, 0.65); + protected $saturation = array(0.35, 0.5, 0.65); + + /** + * Render avatar html + * + * @access public + * @param array $user + * @param int $size + */ + public function render(array $user, $size) + { + $initials = $this->helper->user->getInitials($user['name'] ?: $user['username']); + $rgb = $this->getBackgroundColor($initials); + + return sprintf( + '<div class="avatar-letter" style="background-color: rgb(%d, %d, %d)" title="%s">%s</div>', + $rgb[0], + $rgb[1], + $rgb[2], + $this->helper->text->e($user['name'] ?: $user['username']), + $initials + ); + } + + /** + * Determine if the provider is active + * + * @access public + * @param array $user + * @return boolean + */ + public function isActive(array $user) + { + return true; + } + + /** + * Get background color based on a string + * + * @param string $str + * @return array + */ + public function getBackgroundColor($str) + { + $hsl = $this->getHSL($str); + return $this->getRGB($hsl[0], $hsl[1], $hsl[2]); + } + + /** + * Convert HSL to RGB + * + * @access protected + * @param integer $hue Hue ∈ [0, 360) + * @param integer $saturation Saturation ∈ [0, 1] + * @param integer $lightness Lightness ∈ [0, 1] + * @return array + */ + protected function getRGB($hue, $saturation, $lightness) + { + $hue /= 360; + $q = $lightness < 0.5 ? $lightness * (1 + $saturation) : $lightness + $saturation - $lightness * $saturation; + $p = 2 * $lightness - $q; + + return array_map(function ($color) use ($q, $p) { + if ($color < 0) { + $color++; + } + + if ($color > 1) { + $color--; + } + + if ($color < 1/6) { + $color = $p + ($q - $p) * 6 * $color; + } else if ($color < 0.5) { + $color = $q; + } else if ($color < 2/3) { + $color = $p + ($q - $p) * 6 * (2/3 - $color); + } else { + $color = $p; + } + + return round($color * 255); + }, array($hue + 1/3, $hue, $hue - 1/3)); + } + + /** + * Returns the hash in [h, s, l]. + * Note that H ∈ [0, 360); S ∈ [0, 1]; L ∈ [0, 1]; + * + * @access protected + * @param string $str + * @return int[] + */ + protected function getHSL($str) + { + $hash = $this->hash($str); + $hue = $hash % 359; + + $hash = intval($hash / 360); + $saturation = $this->saturation[$hash % count($this->saturation)]; + + $hash = intval($hash / count($this->saturation)); + $lightness = $this->lightness[$hash % count($this->lightness)]; + + return array($hue, $saturation, $lightness); + } + + /** + * BKDR Hash (modified version) + * + * @access protected + * @param string $str + * @return integer + */ + protected function hash($str) + { + $seed = 131; + $seed2 = 137; + $hash = 0; + + // Make hash more sensitive for short string like 'a', 'b', 'c' + $str .= 'x'; + $max = intval(9007199254740991 / $seed2); + + for ($i = 0, $ilen = mb_strlen($str); $i < $ilen; $i++) { + if ($hash > $max) { + $hash = intval($hash / $seed2); + } + + $hash = $hash * $seed + $this->getCharCode($str[$i]); + } + + return $hash; + } + + /** + * Backport of Javascript function charCodeAt() + * + * @access protected + * @param string $c + * @return integer + */ + protected function getCharCode($c) + { + list(, $ord) = unpack('N', mb_convert_encoding($c, 'UCS-4BE', 'UTF-8')); + return $ord; + } +} |