Skip interface

Author: ivanvermeyen

src/BrowserLocale.php

@@ -2,14 +2,44 @@
 
 namespace CodeZero\BrowserLocale;
 
-interface BrowserLocale
+class BrowserLocale
 {
+    /**
+     * Array of all preferred locales that are
+     * configured in a visitor's browser.
+     *
+     * @var array
+     */
+    protected $locales = [];
+
+    /**
+     * Create a new BrowserLocale instance.
+     *
+     * @param string $httpAcceptLanguages
+     */
+    public function __construct($httpAcceptLanguages = null)
+    {
+        // $_SERVER["HTTP_ACCEPT_LANGUAGE"] will return a comma separated list of language codes.
+        // Each language code MAY have a "relative quality factor" attached ("nl;q=0.8") which
+        // determines the order of preference. For example: "nl-NL,nl;q=0.8,en-US;q=0.6,en;q=0.4"
+        if ($httpAcceptLanguages === null && isset($_SERVER["HTTP_ACCEPT_LANGUAGE"])) {
+            $this->parseAcceptLanguages($_SERVER["HTTP_ACCEPT_LANGUAGE"]);
+        }
+
+        if ($httpAcceptLanguages) {
+            $this->parseAcceptLanguages($httpAcceptLanguages);
+        }
+    }
+
     /**
      * Get the most preferred locale.
      *
      * @return Locale|null
      */
-    public function getLocale();
+    public function getLocale()
+    {
+        return isset($this->locales[0]) ? $this->locales[0] : null;
+    }
 
     /**
      * Get an array of Locale objects in descending order of preference.
@@ -21,5 +51,182 @@ public function getLocale();
      *
      * @return array
      */
-    public function getLocales($propertyFilter = null);
+    public function getLocales($propertyFilter = null)
+    {
+        if ($propertyFilter === null) {
+            return $this->locales;
+        }
+
+        return $this->filterLocaleInfo($propertyFilter);
+    }
+
+    /**
+     * Parse all HTTP Accept Languages.
+     *
+     * @param string $httpAcceptLanguages
+     *
+     * @return void
+     */
+    protected function parseAcceptLanguages($httpAcceptLanguages)
+    {
+        foreach ($this->splitAcceptLanguages($httpAcceptLanguages) as $httpAcceptLanguage) {
+            if ($locale = $this->parseAcceptLanguage($httpAcceptLanguage)) {
+                $this->locales[] = $locale;
+            }
+        }
+
+        $this->sortLocales();
+    }
+
+    /**
+     * Extract and save information from a HTTP Accept Language.
+     *
+     * @param string $httpAcceptLanguage
+     *
+     * @return Locale|null
+     */
+    protected function parseAcceptLanguage($httpAcceptLanguage)
+    {
+        $parts = $this->splitAcceptLanguage($httpAcceptLanguage);
+
+        $locale = isset($parts[0]) ? $parts[0] : null;
+        $weight = isset($parts[1]) ? $parts[1] : null;
+
+        $localeInstance = null;
+
+        if ($locale !== null) {
+            $localeInstance = new Locale();
+            $localeInstance->locale = $locale;
+            $localeInstance->language = $this->getLanguage($locale);
+            $localeInstance->country = $this->getCountry($locale);
+            $localeInstance->weight = $this->getWeight($weight);
+        }
+
+        return $localeInstance;
+    }
+
+    /**
+     * Convert a comma separated list to an array.
+     *
+     * Example: ["en", "en-US;q=0.8"]
+     *
+     * @param string $httpAcceptLanguages
+     *
+     * @return array
+     */
+    protected function splitAcceptLanguages($httpAcceptLanguages)
+    {
+        return explode(',', $httpAcceptLanguages) ?: [];
+    }
+
+    /**
+     * Split a language code and the relative quality factor by semicolon.
+     *
+     * Example: ["en"] or ["en-US"] or ["en-US", "q=0.8"]
+     *
+     * @param string $httpAcceptLanguage
+     *
+     * @return array
+     */
+    protected function splitAcceptLanguage($httpAcceptLanguage)
+    {
+        return explode(';', trim($httpAcceptLanguage)) ?: [];
+    }
+
+    /**
+     * Get the 2-letter language code from the locale.
+     *
+     * Example: "en"
+     *
+     * @param string $locale
+     *
+     * @return string
+     */
+    protected function getLanguage($locale)
+    {
+        return strtolower(substr($locale, 0, 2));
+    }
+
+    /**
+     * Get the 2-letter country code from the locale.
+     *
+     * Example: "US"
+     *
+     * @param string $locale
+     *
+     * @return string
+     */
+    protected function getCountry($locale)
+    {
+        if (($divider = strpos($locale, '-')) === false){
+            return '';
+        }
+
+        return strtoupper(substr($locale, $divider + 1, 2));
+    }
+
+    /**
+     * Parse the relative quality factor and return its value.
+     *
+     * Example: 1.0 or 0.8
+     *
+     * @param string $q
+     *
+     * @return float
+     */
+    protected function getWeight($q)
+    {
+        $weight = 1.0;
+        $parts = explode('=', $q);
+
+        if (isset($parts[1])) {
+            $weight = ((float) $parts[1]);
+        }
+
+        return $weight;
+    }
+
+    /**
+     * Sort the array of locales in descending order of preference.
+     *
+     * @return void
+     */
+    protected function sortLocales()
+    {
+        usort($this->locales, function ($a, $b) {
+            if ($a->weight === $b->weight) {
+                return 0;
+            }
+
+            return ($a->weight > $b->weight) ? -1 : 1;
+        });
+    }
+
+    /**
+     * Get a flattened array of locale information,
+     * containing only the requested property values.
+     *
+     * @param string $property
+     *
+     * @return array
+     */
+    protected function filterLocaleInfo($property)
+    {
+        $filters = ['locale', 'language', 'country', 'weight'];
+        $locales = $this->locales;
+
+        if ( ! in_array($property, $filters)) {
+            return $locales;
+        }
+
+        $filtered = [];
+
+        foreach ($locales as $locale) {
+            if ($locale->$property && ! in_array($locale->$property, $filtered)) {
+                $filtered[] = $locale->$property;
+            }
+        }
+
+        return $filtered;
+    }
 }