laravel-llm-gateway/laravel-app/tests/Unit/Services/OpenAIProviderTest.php

<?php

namespace Tests\Unit\Services;

use Tests\TestCase;
use App\Services\LLM\Providers\OpenAIProvider;
use App\Models\ModelPricing;
use Illuminate\Support\Facades\Http;
use Illuminate\Support\Facades\Cache;
use Illuminate\Foundation\Testing\RefreshDatabase;

class OpenAIProviderTest extends TestCase
{
    use RefreshDatabase;

    private OpenAIProvider $provider;

    protected function setUp(): void
    {
        parent::setUp();
        $this->provider = new OpenAIProvider('test-api-key');
    }

    public function test_builds_request_correctly(): void
    {
        $messages = [
            ['role' => 'user', 'content' => 'Hello']
        ];
        
        $options = [
            'model' => 'gpt-4o-mini',
            'temperature' => 0.8,
            'max_tokens' => 1000
        ];

        $reflection = new \ReflectionClass($this->provider);
        $method = $reflection->getMethod('buildRequest');
        $method->setAccessible(true);

        $result = $method->invoke($this->provider, $messages, $options);

        $this->assertEquals('gpt-4o-mini', $result['model']);
        $this->assertEquals(0.8, $result['temperature']);
        $this->assertEquals(1000, $result['max_tokens']);
        $this->assertEquals($messages, $result['messages']);
        $this->assertFalse($result['stream']);
    }

    public function test_normalizes_response_correctly(): void
    {
        $rawResponse = [
            'id' => 'chatcmpl-123',
            'model' => 'gpt-4o-mini',
            'choices' => [
                [
                    'message' => [
                        'role' => 'assistant',
                        'content' => 'Hello! How can I help you?'
                    ],
                    'finish_reason' => 'stop'
                ]
            ],
            'usage' => [
                'prompt_tokens' => 10,
                'completion_tokens' => 20,
                'total_tokens' => 30
            ]
        ];

        $normalized = $this->provider->normalizeResponse($rawResponse);

        $this->assertEquals('chatcmpl-123', $normalized['id']);
        $this->assertEquals('gpt-4o-mini', $normalized['model']);
        $this->assertEquals('Hello! How can I help you?', $normalized['content']);
        $this->assertEquals('assistant', $normalized['role']);
        $this->assertEquals('stop', $normalized['finish_reason']);
        $this->assertEquals(10, $normalized['usage']['prompt_tokens']);
        $this->assertEquals(20, $normalized['usage']['completion_tokens']);
        $this->assertEquals(30, $normalized['usage']['total_tokens']);
    }

    public function test_calculates_cost_correctly(): void
    {
        // Create pricing in database
        ModelPricing::create([
            'provider' => 'openai',
            'model' => 'gpt-4o-mini',
            'input_price_per_million' => 0.15,
            'output_price_per_million' => 0.60,
            'is_active' => true,
            'effective_from' => now()
        ]);

        Cache::flush();

        $cost = $this->provider->calculateCost(1000, 500, 'gpt-4o-mini');

        // Expected: (1000/1M * 0.15) + (500/1M * 0.60) = 0.00015 + 0.0003 = 0.00045
        $this->assertEquals(0.00045, $cost);
    }

    public function test_handles_api_errors(): void
    {
        Http::fake([
            'https://api.openai.com/*' => Http::response(['error' => 'Invalid API key'], 401)
        ]);

        $this->expectException(\App\Exceptions\ProviderException::class);
        $this->expectExceptionMessage('Invalid API key');

        $this->provider->chatCompletion([
            ['role' => 'user', 'content' => 'test']
        ]);
    }

    public function test_retries_on_server_error(): void
    {
        Http::fake([
            'https://api.openai.com/*' => Http::sequence()
                ->push(['error' => 'Server error'], 500)
                ->push(['error' => 'Server error'], 500)
                ->push([
                    'id' => 'test-123',
                    'model' => 'gpt-4o-mini',
                    'choices' => [[
                        'message' => ['content' => 'Success', 'role' => 'assistant'],
                        'finish_reason' => 'stop'
                    ]],
                    'usage' => ['prompt_tokens' => 10, 'completion_tokens' => 5, 'total_tokens' => 15]
                ], 200)
        ]);

        $result = $this->provider->chatCompletion([
            ['role' => 'user', 'content' => 'test']
        ]);

        $this->assertArrayHasKey('id', $result);
        $this->assertEquals('test-123', $result['id']);
    }

    public function test_get_supported_models(): void
    {
        $models = $this->provider->getSupportedModels();

        $this->assertIsArray($models);
        $this->assertContains('gpt-4o', $models);
        $this->assertContains('gpt-4o-mini', $models);
        $this->assertContains('gpt-3.5-turbo', $models);
    }
}