AndyTranscribe/tests/Unit/WhisperTranscriptionStreamTest.php

<?php

namespace Tests\Unit;

use App\Services\WhisperTranscriptionStream;
use PHPUnit\Framework\TestCase;

class WhisperTranscriptionStreamTest extends TestCase
{
    private WhisperTranscriptionStream $stream;

    protected function setUp(): void
    {
        parent::setUp();

        $this->stream = new WhisperTranscriptionStream;
    }

    public function test_extracts_sse_data_payloads_from_buffer(): void
    {
        $buffer = "data: {\"type\":\"transcript.text.delta\",\"delta\":\"Hello\"}\n\npartial";

        $payloads = $this->stream->extractPayloads($buffer);

        $this->assertSame(['{"type":"transcript.text.delta","delta":"Hello"}'], $payloads);
        $this->assertSame('partial', $buffer);
    }

    public function test_parses_openai_delta_and_done_events(): void
    {
        $delta = $this->stream->parseEvent('{"type":"transcript.text.delta","delta":"Hello "}');
        $done = $this->stream->parseEvent('{"type":"transcript.text.done","text":"Hello world"}');

        $this->assertSame('Hello ', $delta['append']);
        $this->assertFalse($delta['done']);
        $this->assertSame('Hello world', $done['replace']);
        $this->assertTrue($done['done']);
    }

    public function test_parses_legacy_segment_events(): void
    {
        $event = $this->stream->parseEvent('{"text":"First segment","start":0,"end":12.5}');

        $this->assertTrue($event['legacy']);
        $this->assertSame('First segment', $event['append']);
        $this->assertSame(12.5, $event['end']);
        $this->assertSame('First segment', $event['whisper']['segment']['text']);
        $this->assertSame(12.5, $event['whisper']['segment']['end']);
    }

    public function test_parses_typed_segment_events_as_legacy_chunks(): void
    {
        $event = $this->stream->parseEvent(json_encode([
            'type' => 'segment',
            'start' => 0.0,
            'end' => 2.4,
            'text' => 'Hello, how are you?',
            'avg_logprob' => -0.12,
            'words' => [
                ['word' => 'Hello', 'start' => 0.0, 'end' => 0.5, 'probability' => 0.99],
            ],
        ]));

        $this->assertTrue($event['legacy']);
        $this->assertSame('Hello, how are you?', $event['append']);
        $this->assertSame(2.4, $event['end']);
        $this->assertSame(-0.12, $event['whisper']['segment']['avg_logprob']);
        $this->assertSame('Hello', $event['whisper']['segment']['words'][0]['word']);
    }

    public function test_parses_verbose_segment_words_language_and_logprobs(): void
    {
        $json = json_encode([
            'language' => 'en',
            'duration' => 8.5,
            'text' => 'Hello world',
            'id' => 0,
            'start' => 0.0,
            'end' => 1.6,
            'tokens' => [50364, 2425, 1002],
            'avg_logprob' => -0.21,
            'compression_ratio' => 1.15,
            'no_speech_prob' => 0.01,
            'temperature' => 0.0,
            'words' => [
                ['word' => 'Hello', 'start' => 0.0, 'end' => 0.6, 'probability' => 0.94],
                ['word' => 'world', 'start' => 0.7, 'end' => 1.5, 'probability' => 0.88],
            ],
        ]);

        $event = $this->stream->parseEvent($json);

        $this->assertSame('en', $event['whisper']['language']);
        $this->assertSame(8.5, $event['whisper']['duration']);
        $this->assertSame([50364, 2425, 1002], $event['whisper']['segment']['tokens']);
        $this->assertSame(-0.21, $event['whisper']['segment']['avg_logprob']);
        $this->assertCount(2, $event['whisper']['segment']['words']);
        $this->assertSame('Hello', $event['whisper']['segment']['words'][0]['word']);
    }

    public function test_parses_openai_delta_logprobs_without_treating_them_as_a_segment(): void
    {
        $event = $this->stream->parseEvent(json_encode([
            'type' => 'transcript.text.delta',
            'delta' => 'Hel',
            'logprobs' => [
                ['token' => 'Hel', 'logprob' => -0.05],
            ],
        ]));

        $this->assertSame('Hel', $event['append']);
        $this->assertArrayNotHasKey('segment', $event['whisper']);
        $this->assertSame('Hel', $event['whisper']['logprobs'][0]['token']);
        $this->assertSame(-0.05, $event['whisper']['logprobs'][0]['logprob']);
    }

    public function test_applies_delta_then_done_replace(): void
    {
        $delta = $this->stream->parseEvent('{"type":"transcript.text.delta","delta":"Hel"}');
        $text = $this->stream->applyEvent('', $delta);
        $delta2 = $this->stream->parseEvent('{"type":"transcript.text.delta","delta":"lo"}');
        $text = $this->stream->applyEvent($text, $delta2);
        $done = $this->stream->parseEvent('{"type":"transcript.text.done","text":"Hello world"}');
        $text = $this->stream->applyEvent($text, $done);

        $this->assertSame('Hello world', $text);
    }

    public function test_parses_verbose_json_segments_array(): void
    {
        $event = $this->stream->parseEvent(json_encode([
            'task' => 'transcribe',
            'language' => 'en',
            'duration' => 4.2,
            'text' => 'Hello world',
            'segments' => [
                [
                    'id' => 0,
                    'start' => 0.0,
                    'end' => 4.2,
                    'text' => ' Hello world',
                    'avg_logprob' => -0.3,
                    'tokens' => [1, 2],
                    'words' => [
                        ['word' => ' Hello', 'start' => 0.0, 'end' => 0.5, 'probability' => 0.9],
                    ],
                ],
            ],
        ]));

        $this->assertSame('Hello world', $event['replace']);
        $this->assertSame(4.2, $event['end']);
        $this->assertSame('en', $event['whisper']['language']);
        $this->assertCount(1, $event['whisper']['segments']);
        $this->assertSame(-0.3, $event['whisper']['segments'][0]['avg_logprob']);
    }

    public function test_joins_legacy_segments_with_spaces(): void
    {
        $first = $this->stream->parseEvent('{"text":"Hello from","end":10}');
        $second = $this->stream->parseEvent('{"text":"whisper.","end":20}');

        $text = $this->stream->applyEvent('', $first);
        $text = $this->stream->applyEvent($text, $second);

        $this->assertSame('Hello from whisper.', $text);
    }

    public function test_ignores_done_sentinel_and_non_json(): void
    {
        $buffer = "data: [DONE]\n\ndata: not-json\n\n";

        $payloads = $this->stream->extractPayloads($buffer);

        $this->assertSame(['not-json'], $payloads);
        $this->assertNull($this->stream->parseEvent('not-json'));
    }

    public function test_flush_buffer_emits_trailing_frame(): void
    {
        $buffer = 'data: {"text":"Last"}';

        $payloads = $this->stream->flushBuffer($buffer);

        $this->assertSame(['{"text":"Last"}'], $payloads);
        $this->assertSame('', $buffer);
    }

    public function test_openai_delta_uses_word_end_as_audio_position(): void
    {
        $event = $this->stream->parseEvent(json_encode([
            'type' => 'transcript.text.delta',
            'delta' => 'Hello',
            'words' => [
                ['word' => 'Hello', 'start' => 0.0, 'end' => 1.6, 'probability' => 0.9],
            ],
        ]));

        $this->assertSame(1.6, $event['end']);
        $this->assertSame('Hello', $event['whisper']['words'][0]['word']);
    }

    public function test_file_duration_is_not_used_as_audio_position(): void
    {
        $event = $this->stream->parseEvent(json_encode([
            'type' => 'transcript.text.delta',
            'delta' => 'Hello',
            'duration' => 40.0,
        ]));

        $this->assertNull($event['end']);
        $this->assertSame(40.0, $event['whisper']['duration']);
    }
}