embedding 0.1.4

A Rust library and CLI for training embeddings from scratch
Documentation
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
656
657
658
659
660
661
662
663
664
665
666
667
668
669
670
671
672
673
674
675
676
677
678
679
680
681
682
683
684
685
686
687
688
689
690
691
692
693
694
695
696
697
698
699
700
701
702
703
704
705
706
707
708
709
710
711
712
713
714
715
716
717
718
719
720
721
722
723
724
725
726
727
728
729
730
731
732
733
734
735
736
737
738
739
740
741
742
743
744
745
746
747
748
749
750
751
752
753
754
755
756
757
758
759
760
761
762
use embedding::*;

fn make_test_data() -> TrainingData {
    let text = "the cat sat on the mat. the dog sat on the log. the cat chased the dog.";
    let sentences = load_text_data(text);
    let (vocab, reverse_vocab) = build_vocab(&sentences);
    TrainingData { sentences, vocab, reverse_vocab }
}

fn test_config(model_type: ModelType) -> TrainingConfig {
    TrainingConfig::new(model_type)
        .with_dim(8)
        .with_learning_rate(0.1)
        .with_batch_size(4)
        .with_window(1)
        .with_negative_samples(2)
}

#[test]
fn test_end_to_end_training_pipeline() {
    let data = make_test_data();
    let config = test_config(ModelType::SkipGram).with_epochs(3);

    let mut model = EmbeddingModel::new(config, data.vocab.len());
    model.train(&data).expect("Training should succeed");

    // Verify embeddings exist for all vocab words
    for word in data.reverse_vocab.iter() {
        assert!(
            model.get_embedding(word, &data).is_some(),
            "Missing embedding for word: {}",
            word
        );
    }

    // Verify similarity computation
    let sim = model.similarity("cat", "dog", &data);
    assert!(sim.is_some(), "Similarity should be computable for known words");

    // Verify analogy solver doesn't panic
    let results = model.analogy("cat", "dog", "log", &data, 3);
    assert!(results.len() <= 3);
}

#[test]
fn test_save_and_load_embeddings() {
    let data = make_test_data();
    let config = test_config(ModelType::Cbow).with_epochs(2);

    let mut model = EmbeddingModel::new(config.clone(), data.vocab.len());
    model.train(&data).unwrap();

    // Save in Word2Vec format
    let temp_path = std::env::temp_dir().join("integration_word2vec.txt");
    let path_str = temp_path.to_str().unwrap();
    model.save_word2vec_format(path_str, &data).unwrap();

    // Load and verify structure
    let (loaded, dim) = EmbeddingModel::load_word2vec_format(path_str).unwrap();
    assert_eq!(dim, 8);
    assert!(loaded.contains_key("cat"));
    assert!(loaded.contains_key("dog"));
    assert_eq!(loaded.get("cat").unwrap().len(), 8);

    // Save in default format
    let temp_path2 = std::env::temp_dir().join("integration_default.txt");
    let path_str2 = temp_path2.to_str().unwrap();
    model.save_embeddings(path_str2, &data).unwrap();

    let contents = std::fs::read_to_string(path_str2).unwrap();
    assert!(contents.contains("cat"));
    assert!(contents.contains("dog"));

    std::fs::remove_file(path_str).ok();
    std::fs::remove_file(path_str2).ok();
}

#[test]
fn test_text_processing_pipeline() {
    let processor = TextProcessor {
        lowercase: true,
        remove_punctuation: true,
        remove_numbers: true,
        remove_html: true,
        remove_urls: true,
        expand_contractions: true,
        remove_stop_words: false,
        normalize_unicode: false,
        language: "en".to_string(),
    };

    let text = "<p>Visit https://example.com! It's a test with 123 numbers.</p>";
    let sentences = processor.process_text(text);
    assert_eq!(sentences.len(), 1);
    // "visit" stays (not a URL), URL removed, "it's" -> "it is", numbers removed
    assert_eq!(sentences[0], vec!["visit", "it", "is", "a", "test", "with", "numbers"]);
}

#[test]
fn test_cbow_and_skipgram_produce_different_results() {
    let data = make_test_data();

    let config_sg = test_config(ModelType::SkipGram).with_epochs(3);
    let config_cbow = test_config(ModelType::Cbow).with_epochs(3);

    let mut model_sg = EmbeddingModel::new(config_sg, data.vocab.len());
    model_sg.train(&data).unwrap();

    let mut model_cbow = EmbeddingModel::new(config_cbow, data.vocab.len());
    model_cbow.train(&data).unwrap();

    // Both should have embeddings for "cat"
    let emb_sg = model_sg.get_embedding("cat", &data).unwrap();
    let emb_cbow = model_cbow.get_embedding("cat", &data).unwrap();

    // They should not be identical (different training methods)
    let mut identical = true;
    for i in 0..emb_sg.len() {
        if (emb_sg[i] - emb_cbow[i]).abs() > 1e-6 {
            identical = false;
            break;
        }
    }
    assert!(!identical, "SkipGram and CBOW should produce different embeddings");
}

#[test]
fn test_learning_rate_schedule_convergence() {
    let data = make_test_data();

    // Test that different LR schedules all converge (don't panic, produce embeddings)
    let schedules = vec![
        LearningRateSchedule::Constant,
        LearningRateSchedule::Exponential { decay_rate: 0.9 },
        LearningRateSchedule::Step { step_size: 1, gamma: 0.5 },
        LearningRateSchedule::Cosine { t_max: 2 },
    ];

    for schedule in schedules {
        let config = test_config(ModelType::SkipGram)
            .with_epochs(2)
            .with_lr_schedule(schedule);

        let mut model = EmbeddingModel::new(config, data.vocab.len());
        assert!(model.train(&data).is_ok());
        assert!(model.get_embedding("cat", &data).is_some());
    }
}

#[test]
fn test_evaluation_metrics_bounds() {
    let data = make_test_data();
    let config = test_config(ModelType::SkipGram).with_epochs(3);

    let mut model = EmbeddingModel::new(config, data.vocab.len());
    model.train(&data).unwrap();

    let val_data = model.create_validation_data(&data.sentences);
    let metrics = model.evaluate(&data, &val_data);

    // All metrics should be within valid ranges
    assert!((0.0..=1.0).contains(&metrics.accuracy), "Accuracy out of range: {}", metrics.accuracy);
    assert!((0.0..=1.0).contains(&metrics.precision), "Precision out of range: {}", metrics.precision);
    assert!((0.0..=1.0).contains(&metrics.recall), "Recall out of range: {}", metrics.recall);
    assert!((0.0..=1.0).contains(&metrics.f1_score), "F1 out of range: {}", metrics.f1_score);
    assert!(metrics.mean_similarity >= -1.0 && metrics.mean_similarity <= 1.0);
    assert!((0.0..=1.0).contains(&metrics.embedding_quality_score));
}

#[test]
fn test_evaluate_empty_validation() {
    let data = make_test_data();
    let config = test_config(ModelType::SkipGram).with_epochs(2);

    let mut model = EmbeddingModel::new(config, data.vocab.len());
    model.train(&data).unwrap();

    let empty_val = ValidationData {
        positive_pairs: vec![],
        negative_pairs: vec![],
        analogies: vec![],
    };
    let metrics = model.evaluate(&data, &empty_val);
    assert_eq!(metrics.accuracy, 0.0);
    assert_eq!(metrics.precision, 0.0);
    assert_eq!(metrics.recall, 0.0);
    assert_eq!(metrics.f1_score, 0.0);
    assert_eq!(metrics.mean_similarity, 0.0);
}

#[test]
fn test_train_with_validation_ratio_config() {
    let data = make_test_data();
    let mut config = test_config(ModelType::SkipGram)
        .with_epochs(2)
        .with_validation_ratio(0.3);

    let mut model = EmbeddingModel::new(config.clone(), data.vocab.len());
    model.train(&data).unwrap();

    // Re-split manually and validate
    let (train, val) = model.split_data(&data.sentences, 0.7);
    assert!(!train.is_empty());
    assert!(!val.is_empty());

    let val_data = TrainingData {
        sentences: val,
        vocab: data.vocab.clone(),
        reverse_vocab: data.reverse_vocab.clone(),
    };
    let validation_pairs = model.create_validation_data(&val_data.sentences);
    let metrics = model.evaluate(&val_data, &validation_pairs);
    assert!((0.0..=1.0).contains(&metrics.accuracy));

    // Test with 0.0 validation ratio (no split)
    config.validation_ratio = Some(0.0);
    let mut model2 = EmbeddingModel::new(config, data.vocab.len());
    assert!(model2.train(&data).is_ok());
}

#[test]
fn test_create_validation_data_edge_cases() {
    let data = make_test_data();
    let config = test_config(ModelType::SkipGram).with_epochs(2);

    let model = EmbeddingModel::new(config, data.vocab.len());

    // Single sentence
    let single = vec![vec!["hello".to_string(), "world".to_string()]];
    let val = model.create_validation_data(&single);
    assert_eq!(val.positive_pairs.len(), 1);
    assert!(val.negative_pairs.is_empty());

    // Empty sentences
    let empty: Vec<Vec<String>> = vec![];
    let val_empty = model.create_validation_data(&empty);
    assert!(val_empty.positive_pairs.is_empty());
    assert!(val_empty.negative_pairs.is_empty());
    assert!(val_empty.analogies.is_empty());

    // Two-word sentence only
    let two_word = vec![vec!["a".to_string(), "b".to_string(), "c".to_string()]];
    let val2 = model.create_validation_data(&two_word);
    assert!(!val2.positive_pairs.is_empty());
    assert!(!val2.negative_pairs.is_empty());
}

#[test]
fn test_split_data_produces_correct_sizes() {
    let data = make_test_data();
    let config = test_config(ModelType::SkipGram).with_epochs(2);

    let model = EmbeddingModel::new(config, data.vocab.len());

    let (train, val) = model.split_data(&data.sentences, 0.7);
    assert_eq!(train.len() + val.len(), data.sentences.len());

    let (train2, val2) = model.split_data(&data.sentences, 0.5);
    assert_eq!(train2.len() + val2.len(), data.sentences.len());

    let (train3, val3) = model.split_data(&data.sentences, 1.0);
    assert_eq!(train3.len(), data.sentences.len());
    assert!(val3.is_empty());
}

#[test]
fn test_validation_metrics_json_roundtrip() {
    let data = make_test_data();
    let config = test_config(ModelType::SkipGram).with_epochs(2);

    let mut model = EmbeddingModel::new(config, data.vocab.len());
    model.train(&data).unwrap();

    let val_data = model.create_validation_data(&data.sentences);
    let metrics = model.evaluate(&data, &val_data);

    let json = serde_json::to_string_pretty(&metrics).unwrap();
    let parsed: serde_json::Value = serde_json::from_str(&json).unwrap();
    assert!(parsed.get("accuracy").is_some());
    assert!(parsed.get("precision").is_some());
    assert!(parsed.get("recall").is_some());
    assert!(parsed.get("f1_score").is_some());
    assert!(parsed.get("mean_similarity").is_some());
    assert!(parsed.get("embedding_quality_score").is_some());
}

#[test]
fn test_cbow_validation_metrics() {
    let data = make_test_data();
    let config = test_config(ModelType::Cbow).with_epochs(3);

    let mut model = EmbeddingModel::new(config, data.vocab.len());
    model.train(&data).unwrap();

    let val_data = model.create_validation_data(&data.sentences);
    let metrics = model.evaluate(&data, &val_data);
    assert!((0.0..=1.0).contains(&metrics.accuracy));
    assert!((0.0..=1.0).contains(&metrics.f1_score));
}

#[cfg(test)]
mod property_tests {
    use super::*;
    use proptest::prelude::*;

    proptest! {
        #[test]
        fn prop_similarity_range(word1 in "[a-z]{3,8}", word2 in "[a-z]{3,8}") {
            let text = format!("{} {} other words here.", word1, word2);
            let sentences = load_text_data(&text);
            let (vocab, reverse_vocab) = build_vocab(&sentences);
            let data = TrainingData { sentences, vocab, reverse_vocab };
            let config = test_config(ModelType::SkipGram).with_epochs(2);
            let mut model = EmbeddingModel::new(config, data.vocab.len());
            model.train(&data).unwrap();

            if let Some(sim) = model.similarity(&word1, &word2, &data) {
                prop_assert!((-1.0..=1.0).contains(&sim), "Similarity {} out of range [-1, 1]", sim);
            }
        }

        #[test]
        fn prop_normalize_produces_unit_norm(word in "[a-z]{3,8}") {
            let text = format!("{} other words here for context.", word);
            let sentences = load_text_data(&text);
            let (vocab, reverse_vocab) = build_vocab(&sentences);
            let data = TrainingData { sentences, vocab, reverse_vocab };
            let config = test_config(ModelType::SkipGram).with_epochs(2);
            let mut model = EmbeddingModel::new(config, data.vocab.len());
            model.train(&data).unwrap();
            model.normalize_embeddings();

            if let Some(emb) = model.get_embedding(&word, &data) {
                let norm = emb.iter().map(|&x| x * x).sum::<f32>().sqrt();
                if norm > 0.0 {
                    prop_assert!((norm - 1.0).abs() < 1e-5, "Norm {} != 1.0 after normalization", norm);
                }
            }
        }
    }
}

#[test]
fn test_transformer_encoder_shapes_and_variance() {
    let encoder = TransformerEncoder::new(2, 2, 8, 16, 10);

    // All-zeros input should produce non-zero output due to position encoding + weights
    let zeros = ndarray::Array2::zeros((4, 8));
    let encoded = encoder.encode_sequence(&zeros);
    assert_eq!(encoded.nrows(), 4);
    assert_eq!(encoded.ncols(), 8);

    // Single token
    let single = ndarray::Array2::zeros((1, 8));
    let encoded_single = encoder.encode_sequence(&single);
    assert_eq!(encoded_single.nrows(), 1);
    assert_eq!(encoded_single.ncols(), 8);

    // Position encoding produces different values for different positions
    let pos_0 = encoder.position_encoding(3);
    assert_eq!(pos_0.nrows(), 3);
    assert_eq!(pos_0.ncols(), 8);

    // Position 0 and position 1 should differ
    let mut diff_found = false;
    for c in 0..8 {
        if (pos_0[[0, c]] - pos_0[[1, c]]).abs() > 1e-6 {
            diff_found = true;
            break;
        }
    }
    assert!(diff_found, "Position encoding should vary across positions");
}

#[test]
fn test_benchmark_evaluator_load_and_correlation() {
    let tsv = "cat\tdog\t0.8\ncat\tmat\t0.2\ndog\tlog\t0.1\nfox\tdog\t0.5\n";
    let pairs = BenchmarkEvaluator::load_from_tsv(tsv);
    assert_eq!(pairs.len(), 4);
    assert_eq!(pairs[0].word1, "cat");
    assert_eq!(pairs[0].word2, "dog");
    assert!((pairs[0].score - 0.8).abs() < 1e-6);

    let data = make_test_data();
    let config = test_config(ModelType::SkipGram).with_epochs(3);
    let mut model = EmbeddingModel::new(config, data.vocab.len());
    model.train(&data).unwrap();

    let result = BenchmarkEvaluator::evaluate(&model, &data, &pairs);
    assert_eq!(result.num_pairs, 4);
    assert!(result.num_evaluated <= 4);
    assert!(result.correlation >= -1.0 && result.correlation <= 1.0);
    assert_eq!(result.model_scores.len(), result.num_evaluated);
    assert_eq!(result.human_scores.len(), result.num_evaluated);
}

#[test]
fn test_training_history_json_export() {
    let data = make_test_data();
    let config = test_config(ModelType::SkipGram).with_epochs(3);
    let mut model = EmbeddingModel::new(config, data.vocab.len());
    model.train(&data).unwrap();

    assert!(!model.training_history.epochs.is_empty());
    let json = model.training_history.to_json().unwrap();

    let parsed: serde_json::Value = serde_json::from_str(&json).unwrap();
    assert!(parsed.get("epochs").is_some());

    let epochs = parsed["epochs"].as_array().unwrap();
    assert!(!epochs.is_empty());
    assert!(epochs[0].get("epoch").is_some());
    assert!(epochs[0].get("loss").is_some());
    assert!(epochs[0].get("learning_rate").is_some());

    let avg_loss = model.training_history.average_loss();
    assert!(avg_loss >= 0.0);
    let final_loss = model.training_history.final_loss();
    assert!(final_loss >= 0.0);
}

#[test]
fn test_incremental_trainer_end_to_end() {
    let mut data = TrainingData::from_text("the cat sat on the mat");
    let config = TrainingConfig::new(ModelType::SkipGram)
        .with_dim(4)
        .with_epochs(1)
        .with_batch_size(2)
        .with_window(1)
        .with_negative_samples(1);
    let mut model = EmbeddingModel::new(config, data.vocab.len());
    model.train(&data).unwrap();

    let original_vocab = data.vocab.len();
    let new_sentences = vec![
        vec!["newword".to_string(), "cat".to_string()],
    ];

    IncrementalTrainer::update(&mut model, &mut data, &new_sentences, 1).unwrap();

    // Vocabulary should have grown
    assert!(data.vocab.len() > original_vocab);
    // New word should be in vocab
    assert!(data.vocab.contains_key("newword"));
    // Existing word should still be there
    assert!(data.vocab.contains_key("cat"));

    // Model should be able to embed new words
    assert!(model.get_embedding("newword", &data).is_some());
}

#[test]
fn test_incremental_stream_train() {
    let mut data = TrainingData::from_text("hello world foo bar");
    let config = TrainingConfig::new(ModelType::SkipGram)
        .with_dim(4)
        .with_epochs(1)
        .with_batch_size(2)
        .with_window(1)
        .with_negative_samples(1);
    let mut model = EmbeddingModel::new(config, data.vocab.len());
    model.train(&data).unwrap();

    let stream = vec![
        vec!["stream".to_string(), "word".to_string()],
        vec!["another".to_string(), "stream".to_string()],
    ];

    IncrementalTrainer::stream_train(&mut model, &mut data, stream.into_iter(), 1, 1).unwrap();

    assert!(data.vocab.contains_key("stream"));
    assert!(data.vocab.contains_key("word"));
    assert!(data.vocab.contains_key("another"));
}

#[test]
fn test_multimodal_fusion_all_methods() {
    let fusion = MultimodalFusion::new(4, 4, 4);
    let text = ndarray::Array1::from_vec(vec![1.0, 0.0, 0.0, 0.0]);
    let aux = ndarray::Array1::from_vec(vec![0.0, 1.0, 0.0, 0.0]);

    // Concatenation
    let concat = fusion.concatenate(&text, &aux);
    assert_eq!(concat.len(), 8);
    assert_eq!(concat[0], 1.0);
    assert_eq!(concat[4], 0.0);

    // Weighted average
    let avg = fusion.weighted_average(&text, &aux, 0.7).unwrap();
    assert_eq!(avg.len(), 4);
    assert!((avg[0] - 0.7).abs() < 1e-6);
    assert!((avg[1] - 0.3).abs() < 1e-6);

    // Mismatched dims should return None
    let short = ndarray::Array1::from_vec(vec![1.0, 2.0]);
    assert!(fusion.weighted_average(&text, &short, 0.5).is_none());

    // Attention fusion
    let attn = fusion.attention_fusion(&text, &aux).unwrap();
    assert_eq!(attn.len(), 4);

    // Cross-modal similarity - orthogonal vectors should be ~0
    let sim = MultimodalFusion::cross_modal_similarity(&text, &aux);
    assert!(sim.abs() < 1e-5, "Orthogonal vectors should have ~0 similarity, got {}", sim);

    // Same vector should be ~1
    let sim_same = MultimodalFusion::cross_modal_similarity(&text, &text);
    assert!((sim_same - 1.0).abs() < 1e-5, "Same vector should have similarity ~1, got {}", sim_same);
}

#[test]
fn test_kmeans_clustering_basic() {
    let data = make_test_data();
    let config = test_config(ModelType::SkipGram).with_epochs(3);
    let mut model = EmbeddingModel::new(config, data.vocab.len());
    model.train(&data).unwrap();

    let clusters = search::KMeansClustering::cluster(&model, &data, 3, 20);
    assert!(!clusters.is_empty());
    assert!(clusters.len() <= 3);

    // All words should be assigned to exactly one cluster
    let total_words: usize = clusters.iter().map(|c| c.len()).sum();
    assert_eq!(total_words, data.vocab.len());

    // Clusters should not overlap
    let mut seen = std::collections::HashSet::new();
    for cluster in &clusters {
        for word in cluster {
            assert!(seen.insert(word.clone()), "Word {} in multiple clusters", word);
        }
    }
}

#[test]
fn test_kmeans_hierarchical_comparison() {
    let data = make_test_data();
    let config = test_config(ModelType::SkipGram).with_epochs(3);
    let mut model = EmbeddingModel::new(config, data.vocab.len());
    model.train(&data).unwrap();

    // Both clustering methods should produce valid clusters
    let kmeans = search::KMeansClustering::cluster(&model, &data, 3, 20);
    let hier = search::HierarchicalClustering::cluster(&model, &data, 3);

    assert!(!kmeans.is_empty());
    assert!(!hier.is_empty());

    let kmeans_total: usize = kmeans.iter().map(|c| c.len()).sum();
    let hier_total: usize = hier.iter().map(|c| c.len()).sum();
    assert_eq!(kmeans_total, data.vocab.len());
    assert_eq!(hier_total, data.vocab.len());
}

#[test]
fn test_cross_validation_skipgram_and_cbow() {
    let data = make_test_data();

    for model_type in [ModelType::SkipGram, ModelType::Cbow] {
        let config = test_config(model_type).with_epochs(2);
        let model = EmbeddingModel::new(config, data.vocab.len());

        let cv = model.cross_validate(&data, 3).unwrap();
        assert_eq!(cv.folds, 3);
        assert_eq!(cv.per_fold_metrics.len(), 3);

        // Averaged metrics should be within valid ranges
        assert!(cv.averaged_metrics.accuracy >= 0.0 && cv.averaged_metrics.accuracy <= 1.0);
        assert!(cv.averaged_metrics.f1_score >= 0.0 && cv.averaged_metrics.f1_score <= 1.0);

        // Per-fold metrics should also be valid
        for metrics in &cv.per_fold_metrics {
            assert!(metrics.accuracy >= 0.0 && metrics.accuracy <= 1.0);
        }
    }
}

#[test]
fn test_wordpiece_tokenizer_roundtrip() {
    let corpus = vec![
        "hello".to_string(),
        "world".to_string(),
        "hello".to_string(),
        "world".to_string(),
        "helloworld".to_string(),
    ];
    let tokenizer = WordPieceTokenizer::train(&corpus, 50);
    assert!(tokenizer.vocab_size > 0);

    let encoded = tokenizer.encode("hello world");
    assert!(!encoded.is_empty());

    let decoded = tokenizer.decode(&encoded);
    // Decoding may produce "hello world" or a close approximation
    assert!(!decoded.is_empty());

    // Single word
    let single = tokenizer.encode("hello");
    assert!(!single.is_empty());
    let single_decoded = tokenizer.decode(&single);
    assert_eq!(single_decoded, "hello");
}

#[test]
fn test_cpu_backend_operations() {
    let backend = CpuBackend::new();
    assert_eq!(backend.name(), "cpu");

    let emb = backend.init_embeddings(10, 8);
    assert_eq!(emb.nrows(), 10);
    assert_eq!(emb.ncols(), 8);

    let a = ndarray::Array1::from_vec(vec![1.0, 2.0, 3.0]);
    let b = ndarray::Array1::from_vec(vec![4.0, 5.0, 6.0]);
    let dot = backend.dot(&a, &b);
    assert!((dot - 32.0).abs() < 1e-5, "Expected 32.0, got {}", dot);

    let mut c = a.clone();
    backend.add_scaled(&mut c, &b, 2.0);
    assert_eq!(c.to_vec(), vec![9.0, 12.0, 15.0]);
}

#[test]
fn test_mmap_embeddings_save_and_load() {
    let data = make_test_data();
    let config = test_config(ModelType::SkipGram).with_epochs(2);
    let mut model = EmbeddingModel::new(config, data.vocab.len());
    model.train(&data).unwrap();

    let temp = std::env::temp_dir().join("integration_mmap.bin");
    let path = temp.to_str().unwrap();

    model.save_mmapable_format(path, &data).unwrap();
    let mmap = EmbeddingModel::load_mmap(path).unwrap();

    assert_eq!(mmap.vocab_size(), data.vocab.len());
    assert_eq!(mmap.dim(), model.config.embedding_dim);

    let cat_id = data.vocab["cat"];
    let expected: Vec<f32> = model.embeddings.row(cat_id).to_vec();
    assert_eq!(mmap.get("cat").unwrap(), expected);

    let mut count = 0;
    for (word, emb) in mmap.iter() {
        assert!(!word.is_empty());
        assert_eq!(emb.len(), model.config.embedding_dim);
        count += 1;
    }
    assert_eq!(count, data.vocab.len());

    assert!(mmap.get("nonexistent").is_none());

    std::fs::remove_file(path).ok();
}

#[test]
fn test_pretrained_loader_word2vec_text_auto() {
    let temp = std::env::temp_dir().join("integration_pretrained_w2v.txt");
    let path = temp.to_str().unwrap();

    std::fs::write(
        path,
        "3 4\ncat 0.1 0.2 0.3 0.4\ndog 0.5 0.6 0.7 0.8\nfish 0.9 0.0 0.1 0.2\n",
    )
    .unwrap();

    let emb = PretrainedLoader::auto(path).unwrap();
    assert_eq!(emb.dim(), 4);
    assert_eq!(emb.vocab_size(), 3);
    assert!(emb.contains("cat"));
    assert!(emb.contains("dog"));
    assert!(!emb.contains("elephant"));

    let cat = emb.get("cat").unwrap();
    assert_eq!(cat.len(), 4);
    assert!((cat[0] - 0.1).abs() < 1e-6);

    std::fs::remove_file(path).ok();
}

#[test]
fn test_pretrained_embeddings_similarity_and_most_similar() {
    let mut emb = PretrainedEmbeddings::new(3);
    emb.insert("a".to_string(), vec![1.0, 0.0, 0.0]);
    emb.insert("b".to_string(), vec![0.0, 1.0, 0.0]);
    emb.insert("c".to_string(), vec![1.0, 0.0, 0.0]);

    let sim_ab = emb.similarity("a", "b").unwrap();
    assert!(sim_ab.abs() < 1e-5);

    let sim_ac = emb.similarity("a", "c").unwrap();
    assert!((sim_ac - 1.0).abs() < 1e-5);

    assert!(emb.similarity("a", "missing").is_none());

    let similar = emb.most_similar("a", 1);
    assert_eq!(similar.len(), 1);
    assert_eq!(similar[0].0, "c");
}

#[test]
fn test_pretrained_loader_glove_format_explicit() {
    let temp = std::env::temp_dir().join("integration_pretrained_glove.txt");
    let path = temp.to_str().unwrap();

    std::fs::write(path, "2 3\nhello 0.1 0.2 0.3\nworld 0.4 0.5 0.6\n").unwrap();

    let emb = PretrainedLoader::with_format(path, embedding::pretrained::PretrainedFormat::GloVe)
        .unwrap();
    assert_eq!(emb.dim(), 3);
    assert_eq!(emb.vocab_size(), 2);
    assert_eq!(emb.get("hello").unwrap(), &[0.1, 0.2, 0.3]);

    std::fs::remove_file(path).ok();
}

#[test]
fn test_pretrained_init_model_from_pretrained() {
    let temp = std::env::temp_dir().join("integration_pretrained_init.txt");
    let path = temp.to_str().unwrap();

    std::fs::write(
        path,
        "3 8\ncat 0.1 0.1 0.1 0.1 0.1 0.1 0.1 0.1\ndog 0.2 0.2 0.2 0.2 0.2 0.2 0.2 0.2\nthe 0.3 0.3 0.3 0.3 0.3 0.3 0.3 0.3\n",
    )
    .unwrap();

    let data = make_test_data();
    let config = test_config(ModelType::SkipGram);
    let model = EmbeddingModel::new_with_pretrained(config, data.vocab.len(), &data, path).unwrap();

    let cat_id = data.vocab["cat"];
    let cat_emb = model.embeddings.row(cat_id);
    for &v in cat_emb.iter() {
        assert!((v - 0.1).abs() < 1e-5);
    }

    std::fs::remove_file(path).ok();
}

#[test]
fn test_pretrained_loader_from_mmap_binary() {
    let data = make_test_data();
    let config = test_config(ModelType::SkipGram).with_epochs(2);
    let mut model = EmbeddingModel::new(config, data.vocab.len());
    model.train(&data).unwrap();

    let temp = std::env::temp_dir().join("integration_pretrained_mmap.bin");
    let path = temp.to_str().unwrap();

    model.save_mmapable_format(path, &data).unwrap();

    let emb = PretrainedLoader::auto(path).unwrap();
    assert_eq!(emb.dim(), model.config.embedding_dim);
    assert_eq!(emb.vocab_size(), data.vocab.len());

    let cat_id = data.vocab["cat"];
    let expected: Vec<f32> = model.embeddings.row(cat_id).to_vec();
    assert_eq!(emb.get("cat").unwrap(), expected.as_slice());

    std::fs::remove_file(path).ok();
}