Show actual AI token usage and cost

administrator/components/com_testquestions/src/Service/AiService.php

@@ -73,9 +73,46 @@ class AiService
             throw new \RuntimeException('AI zwróciło nieprawidłowy format oceny i punktów.');
         }
 
+        $usage = $this->getUsage($body, $provider, $config['model']);
+
         return [
             'awarded_points' => min(max(0, $maxPoints), max(0, (int) $result['awarded_points'])),
             'feedback' => trim((string) ($result['feedback'] ?? '')),
+            'usage' => $usage,
+        ];
+    }
+
+    private function getUsage(array $body, string $provider, string $model): ?array
+    {
+        $usage = $body['usage'] ?? null;
+        if (!is_array($usage) || !isset($usage['input_tokens'], $usage['output_tokens'])) {
+            return null;
+        }
+
+        $inputTokens = max(0, (int) $usage['input_tokens']);
+        $outputTokens = max(0, (int) $usage['output_tokens']);
+        $cachedTokens = min($inputTokens, max(0, (int) ($usage['input_tokens_details']['cached_tokens'] ?? 0)));
+        $cost = null;
+        $costSource = '';
+
+        if ($provider === 'grok' && isset($usage['cost_in_usd_ticks']) && is_numeric($usage['cost_in_usd_ticks'])) {
+            $cost = (float) $usage['cost_in_usd_ticks'] / 10000000000;
+            $costSource = 'provider';
+        } elseif ($provider === 'openai' && $model === 'gpt-4.1-mini') {
+            $uncachedTokens = $inputTokens - $cachedTokens;
+            $cost = ($uncachedTokens * 0.40 + $cachedTokens * 0.10 + $outputTokens * 1.60) / 1000000;
+            $costSource = 'token_rates';
+        }
+
+        return [
+            'provider' => $provider,
+            'model' => $model,
+            'input_tokens' => $inputTokens,
+            'output_tokens' => $outputTokens,
+            'total_tokens' => (int) ($usage['total_tokens'] ?? ($inputTokens + $outputTokens)),
+            'cached_input_tokens' => $cachedTokens,
+            'cost_usd' => $cost,
+            'cost_source' => $costSource,
         ];
     }