[I18N] Overhaul _m() implementation to support ICU message formats

src/Core/I18n/I18n.php

@@ -88,28 +88,33 @@ function _m(string $msg /*, ...*/): string
     $args   = func_get_args();
     switch (count($args)) {
     case 1:
-        // Empty parameters
+        // Empty parameters, simple message
         return I18nHelper::$translator->trans($msg, [], $domain);
-    case 2:
-        $context    = $args[0];
-        $msg_single = $args[1];
-        // ASCII 4 is EOT, used to separate context from string
-        return I18nHelper::$translator->trans($context . '\004' . $msg_single, [], $domain);
     case 3:
-        // '|' separates the singular from the plural version
+        if (is_int($args[2])) {
-        $msg_single = $args[0];
+            throw new Exception('Calling `_m()` with an explicit number is deprecated, ' .
-        $msg_plural = $args[1];
+                                'use an explicit parameter');
-        $n          = $args[2];
+        }
-        return I18nHelper::$translator->trans($msg_single . '|' . $msg_plural, ['%d' => $n], $domain);
+        // Falthrough
-    case 4:
+        // no break
-        // Combine both
+    case 2:
-        $context    = $args[0];
+        if (is_string($args[0]) && !is_array($args[1])) {
-        $msg_single = $args[1];
+            // ASCII 4 is EOT, used to separate context from string
-        $msg_plural = $args[2];
+            $context = array_shift($args) . '\004';
-        $n          = $args[3];
+        }
-        return I18nHelper::$translator->trans($context . '\004' . $msg_single . '|' . $msg_plural,
+
-                                              ['%d' => $n], $domain);
+        if (is_array($args[0])) {
+            $args[0] = I18nHelper::formatICU($args[0], $args[1]);
+        }
+
+        if (is_string($args[0])) {
+            $msg    = $args[0];
+            $params = $args[1] ?? [];
+            return I18nHelper::$translator->trans($context ?? '' . $msg, $params, $domain);
+        }
+        // Fallthrough
+        // no break
     default:
-        throw new InvalidArgumentException('Bad parameter count to _m()');
+        throw new InvalidArgumentException('Bad parameters to `_m()`');
     }
 }

src/Core/I18n/I18nHelper.php

@@ -214,4 +214,41 @@ abstract class I18nHelper
             'vi'        => ['q' => 0.8, 'lang' => 'vi', 'name' => 'Vietnamese', 'direction' => 'ltr'],
         ];
     }
+
+    public static function formatICU(array $messages, array $params): string
+    {
+        $msg = '';
+        foreach ($params as $var => $val) {
+            if (is_int($var)) {
+                $pref = '=';
+                $op   = 'plural';
+            } elseif (is_string($var)) {
+                $pref = '';
+                $op   = 'select,';
+            } else {
+                throw new Exception('Invalid key type. (int|string) only');
+            }
+
+            $res = "{{$var}, {$op} ";
+            $i   = 1;
+            $cnt = count($messages);
+            foreach ($messages as $val => $m) {
+                if (is_array($m)) {
+                    array_shift($params);
+                    $res .= "{$pref}{$val} {" . self::formatICU($m, $params) . '} ';
+                } elseif (is_string($m)) {
+                    if ($i !== $cnt) {
+                        $res .= "{$pref}{$val} {{$m}} ";
+                    } else {
+                        $res .= "other {{$m}}}";
+                    }
+                } else {
+                    throw new Exception('Invalid message array');
+                }
+                ++$i;
+            }
+            $msg .= $res;
+        }
+        return $msg;
+    }
 }