aprender-core 0.29.2

use super::*;

#[test]
fn test_decode_byte_token() {
    // Create tokenizer with byte token for newline
    let tokens = vec![
        "<unk>".to_string(),
        "<s>".to_string(),
        "</s>".to_string(),
        "<0x0A>".to_string(), // newline byte token
    ];
    let scores = vec![0.0; tokens.len()];
    let tokenizer = LlamaTokenizer::new(tokens, scores, 1, 2, 0).unwrap();

    let decoded = tokenizer.decode(&[3]); // decode byte token
    assert_eq!(decoded, "\n");
}

#[test]
fn test_decode_invalid_byte_token() {
    // Create tokenizer with malformed byte token
    let tokens = vec![
        "<unk>".to_string(),
        "<s>".to_string(),
        "</s>".to_string(),
        "<0xZZ>".to_string(), // invalid hex
    ];
    let scores = vec![0.0; tokens.len()];
    let tokenizer = LlamaTokenizer::new(tokens, scores, 1, 2, 0).unwrap();

    // Should not panic, just output the token as-is
    let decoded = tokenizer.decode(&[3]);
    assert_eq!(decoded, "<0xZZ>");
}

#[test]
fn test_encode_gpt2_mode() {
    let mut tokenizer = create_test_tokenizer();
    tokenizer.set_model(TokenizerModel::Gpt2);

    let tokens = tokenizer.encode("Hello World");
    assert!(!tokens.is_empty());
}

#[test]
fn test_from_gguf_too_short() {
    let short_data = b"GGUF";
    let result = LlamaTokenizer::from_gguf_bytes(short_data);
    assert!(result.is_err());
}

#[test]
fn test_from_gguf_missing_tokens() {
    // Create GGUF without tokenizer.ggml.tokens
    let mut data = Vec::new();
    data.extend_from_slice(b"GGUF");
    data.extend_from_slice(&3u32.to_le_bytes()); // version
    data.extend_from_slice(&0u64.to_le_bytes()); // tensor_count
    data.extend_from_slice(&0u64.to_le_bytes()); // metadata_count (zero)

    let result = LlamaTokenizer::from_gguf_bytes(&data);
    assert!(result.is_err());
}

#[test]
fn test_gguf_value_variants() {
    // Test GGUFValue enum variants
    let values = vec![
        GGUFValue::UInt8(1),
        GGUFValue::Int8(-1),
        GGUFValue::UInt16(100),
        GGUFValue::Int16(-100),
        GGUFValue::UInt32(1000),
        GGUFValue::Int32(-1000),
        GGUFValue::Float32(1.5),
        GGUFValue::Bool(true),
        GGUFValue::String("test".to_string()),
        GGUFValue::Array(vec![GGUFValue::UInt8(1)]),
        GGUFValue::UInt64(10000),
        GGUFValue::Int64(-10000),
        GGUFValue::Float64(3.14),
    ];

    for val in &values {
        let debug = format!("{:?}", val);
        assert!(!debug.is_empty());
    }

    // Clone test
    let cloned = values.clone();
    assert_eq!(values.len(), cloned.len());
}

#[test]
fn test_decode_gpt2_non_mapped_char() {
    // Test decoding a character not in GPT-2 mapping
    // Should fallback to UTF-8 encoding
    let bytes = decode_gpt2_token("日本語"); // Japanese characters
    let text = String::from_utf8_lossy(&bytes);
    assert!(!text.is_empty());
}

#[test]
fn test_gpt2_decode_full_sentence() {
    let mut tokenizer = create_test_tokenizer();
    tokenizer.set_model(TokenizerModel::Gpt2);

    // Test decode_gpt2 path with special tokens
    let decoded = tokenizer.decode(&[
        tokenizer.bos_token_id(),
        3, // some token
        tokenizer.eos_token_id(),
    ]);
    // BOS and EOS should be filtered
    assert!(!decoded.contains("<s>"));
    assert!(!decoded.contains("</s>"));
}

#[test]
fn test_vocab_size_accessor() {
    let tokenizer = create_test_tokenizer();
    assert!(tokenizer.vocab_size() > 0);
}

#[test]
fn test_constants() {
    assert_eq!(LLAMA_VOCAB_SIZE, 32000);
    assert_eq!(BOS_TOKEN, "<s>");
    assert_eq!(EOS_TOKEN, "</s>");
    assert_eq!(UNK_TOKEN, "<unk>");
}

#[test]
fn test_encode_with_byte_fallback_for_emoji() {
    // Create tokenizer with byte tokens
    let mut tokens = vec![
        "<unk>".to_string(),
        "<s>".to_string(),
        "</s>".to_string(),
        "▁Hello".to_string(),
    ];
    // Add byte tokens for 0x00 to 0xFF
    for i in 0u8..=255 {
        tokens.push(format!("<0x{i:02X}>"));
    }
    let scores = vec![0.0; tokens.len()];
    let tokenizer = LlamaTokenizer::new(tokens, scores, 1, 2, 0).unwrap();

    // Encode text with emoji (uses byte fallback)
    let encoded = tokenizer.encode("🎉");
    assert!(!encoded.is_empty());
}

#[test]
fn test_decode_skips_unknown_token_id() {
    let tokenizer = create_test_tokenizer();
    // Decode with non-existent token ID
    let decoded = tokenizer.decode(&[9999]);
    // Should not panic, produces empty for missing token
    assert!(decoded.is_empty() || decoded.len() > 0);
}

#[test]
fn test_gpt2_byte_decoder_size() {
    let decoder = build_gpt2_byte_decoder();
    // GPT-2 byte decoder should have 256 entries
    assert_eq!(decoder.len(), 256);
}

#[test]
fn test_decode_sentencepiece_handles_hybrid_space() {
    // Test that hybrid tokenizers with GPT-2 space marker work
    let tokens = vec![
        "<unk>".to_string(),
        "<s>".to_string(),
        "</s>".to_string(),
        "Ġworld".to_string(), // GPT-2 space marker
    ];
    let scores = vec![0.0; tokens.len()];
    let tokenizer = LlamaTokenizer::new(tokens, scores, 1, 2, 0).unwrap();

    let decoded = tokenizer.decode(&[3]);
    assert_eq!(decoded, "world"); // Leading space removed
}

// ========================================================================
// Additional Coverage Tests for 95% Target
// ========================================================================

#[test]
fn test_pad_token_accessors() {
    let tokens = vec![
        "<unk>".to_string(),
        "<s>".to_string(),
        "</s>".to_string(),
        "<pad>".to_string(),
    ];
    let scores = vec![0.0; tokens.len()];
    let tokenizer = LlamaTokenizer::new(tokens, scores, 1, 2, 0).unwrap();

    // PAD token not set by default
    assert!(tokenizer.pad_token_id.is_none());
}

#[test]
fn test_encode_long_text() {
    let tokenizer = create_test_tokenizer();
    // Test with text longer than 32 chars (max substring check)
    let long_text = "Hello World Hello World Hello World Hello World";
    let tokens = tokenizer.encode(long_text);
    assert!(!tokens.is_empty());
}

#[test]
fn test_encode_special_chars() {
    let tokenizer = create_test_tokenizer();
    let text_with_special = "Hello\tWorld\nNew Line";
    let tokens = tokenizer.encode(text_with_special);
    assert!(!tokens.is_empty());
}

#[test]
fn test_encode_numbers() {
    let tokenizer = create_test_tokenizer();
    let numeric = "12345 67890";
    let tokens = tokenizer.encode(numeric);
    assert!(!tokens.is_empty());
}

#[test]
fn test_decode_empty() {
    let tokenizer = create_test_tokenizer();
    let decoded = tokenizer.decode(&[]);
    assert!(decoded.is_empty());
}

#[test]
fn test_decode_gpt2_with_all_special_tokens() {
    let tokens = vec![
        "<unk>".to_string(),
        "<|endoftext|>".to_string(),
        "</s>".to_string(),
        "test".to_string(),
    ];
    let scores = vec![0.0; tokens.len()];
    let mut tokenizer = LlamaTokenizer::new(tokens, scores, 1, 2, 0).unwrap();
    tokenizer.set_model(TokenizerModel::Gpt2);

    // Decode with only special tokens
    let decoded = tokenizer.decode(&[1, 2]); // BOS and EOS
    assert!(decoded.is_empty());
}

#[test]
fn test_decode_gpt2_mixed_tokens() {
    let tokens = vec![
        "<unk>".to_string(),
        "<|endoftext|>".to_string(),
        "</s>".to_string(),
        "Hello".to_string(),
        "Ġworld".to_string(),
    ];
    let scores = vec![0.0; tokens.len()];
    let mut tokenizer = LlamaTokenizer::new(tokens, scores, 1, 2, 0).unwrap();
    tokenizer.set_model(TokenizerModel::Gpt2);

    let decoded = tokenizer.decode(&[1, 3, 4, 2]); // BOS, Hello, world, EOS
    assert_eq!(decoded, "Hello world");
}

#[test]
fn test_encode_gpt2_with_newlines() {
    let tokens = vec![
        "<unk>".to_string(),
        "<s>".to_string(),
        "</s>".to_string(),
        "Hello".to_string(),
        "Ċworld".to_string(), // newline prefix
    ];
    let scores = vec![0.0; tokens.len()];
    let mut tokenizer = LlamaTokenizer::new(tokens, scores, 1, 2, 0).unwrap();
    tokenizer.set_model(TokenizerModel::Gpt2);

    let encoded = tokenizer.encode("test\nline");
    assert!(!encoded.is_empty());
}

#[test]
fn test_token_to_id_all_tokens() {
    let tokenizer = create_test_tokenizer();

    // Test all known tokens
    assert!(tokenizer.token_to_id("<unk>").is_some());
    assert!(tokenizer.token_to_id("<s>").is_some());
    assert!(tokenizer.token_to_id("</s>").is_some());
}

#[test]
fn test_id_to_token_boundary() {
    let tokenizer = create_test_tokenizer();

    // Test boundary conditions
    assert!(tokenizer.id_to_token(0).is_some()); // First token
    assert!(tokenizer
        .id_to_token(tokenizer.vocab_size() as u32 - 1)
        .is_some()); // Last valid
    assert!(tokenizer
        .id_to_token(tokenizer.vocab_size() as u32)
        .is_none()); // Out of bounds
}

#[test]
fn test_eos_token_id_accessor() {
    let tokenizer = create_test_tokenizer();
    assert_eq!(tokenizer.eos_token_id(), 2);
}

#[test]
fn test_unk_token_id_accessor() {
    let tokenizer = create_test_tokenizer();
    assert_eq!(tokenizer.unk_token_id(), 0);
}

#[test]
fn test_bos_token_id_accessor() {
    let tokenizer = create_test_tokenizer();
    assert_eq!(tokenizer.bos_token_id(), 1);
}

#[test]
fn test_encode_with_bos_empty() {
    let tokenizer = create_test_tokenizer();
    let tokens = tokenizer.encode_with_bos("");
    assert_eq!(tokens.len(), 1);
    assert_eq!(tokens[0], tokenizer.bos_token_id());
}

#[test]
fn test_encode_with_bos_single_word() {
    let tokenizer = create_test_tokenizer();
    let tokens = tokenizer.encode_with_bos("Hello");
    assert!(tokens.len() >= 2); // BOS + at least one token
    assert_eq!(tokens[0], tokenizer.bos_token_id());
}

#[test]
fn test_decode_sentencepiece_byte_fallback_invalid() {
    // Create tokenizer with incomplete byte token
    let tokens = vec![
        "<unk>".to_string(),
        "<s>".to_string(),
        "</s>".to_string(),
        "<0x".to_string(), // Malformed - no closing >
    ];
    let scores = vec![0.0; tokens.len()];
    let tokenizer = LlamaTokenizer::new(tokens, scores, 1, 2, 0).unwrap();

    let decoded = tokenizer.decode(&[3]);
    // Should not crash, just output token as-is
    assert_eq!(decoded, "<0x");
}

#[test]
fn test_from_gguf_bytes_v1_format() {
    // Test GGUF version 1 (if supported)
    let mut data = Vec::new();
    data.extend_from_slice(b"GGUF");
    data.extend_from_slice(&1u32.to_le_bytes()); // version 1
    data.extend_from_slice(&0u64.to_le_bytes());
    data.extend_from_slice(&0u64.to_le_bytes());

    // This may fail if v1 isn't supported
    let result = LlamaTokenizer::from_gguf_bytes(&data);
    // Just verify it doesn't panic
    let _ = result.is_ok();
}

#[test]
fn test_gguf_value_array_nested() {
    let values = GGUFValue::Array(vec![
        GGUFValue::Array(vec![GGUFValue::UInt8(1), GGUFValue::UInt8(2)]),
        GGUFValue::Array(vec![GGUFValue::UInt8(3), GGUFValue::UInt8(4)]),
    ]);

    let debug = format!("{:?}", values);
    assert!(debug.contains("Array"));
}

#[test]
fn test_tokenizer_model_values() {
    // Test all TokenizerModel variants
    let sp = TokenizerModel::SentencePiece;
    let gpt2 = TokenizerModel::Gpt2;

    assert_ne!(sp, gpt2);
    assert_eq!(sp, TokenizerModel::default());
}

#[test]
fn test_encode_all_unk() {
    // Create tokenizer with minimal vocab
    let tokens = vec!["<unk>".to_string(), "<s>".to_string(), "</s>".to_string()];
    let scores = vec![0.0; tokens.len()];
    let tokenizer = LlamaTokenizer::new(tokens, scores, 1, 2, 0).unwrap();

    // Encode text that has no matching tokens
    let encoded = tokenizer.encode("xyz123");
    // Should use byte fallback or UNK
    assert!(!encoded.is_empty());
}

#[test]
fn test_decode_multiple_byte_tokens() {
    // Create tokenizer with multiple byte tokens
    let mut tokens = vec!["<unk>".to_string(), "<s>".to_string(), "</s>".to_string()];
    // Add byte tokens
    for i in 0u8..10 {
        tokens.push(format!("<0x{:02X}>", i));
    }
    let scores = vec![0.0; tokens.len()];
    let tokenizer = LlamaTokenizer::new(tokens, scores, 1, 2, 0).unwrap();

    // Decode multiple consecutive byte tokens
    let decoded = tokenizer.decode(&[3, 4, 5]); // <0x00>, <0x01>, <0x02>
    assert_eq!(decoded.len(), 3);
}

#[test]
fn test_gpt2_byte_decoder_all_chars() {
    let decoder = build_gpt2_byte_decoder();

    // Verify all 256 bytes are mapped
    assert_eq!(decoder.len(), 256);

    // Verify specific mappings
    for b in b'!'..=b'~' {
        assert!(decoder.values().any(|&v| v == b));
    }
}

#[test]
fn test_decode_gpt2_token_complex() {
    // Test complex unicode sequences
    let token = "HelloĠworldĊnewline";
    let bytes = decode_gpt2_token(token);

    // Should contain space for Ġ and newline for Ċ
    let text = String::from_utf8_lossy(&bytes);
    assert!(text.contains(" ")); // Ġ → space
    assert!(text.contains("\n")); // Ċ → newline
}