# /// script
# dependencies = ["transformers>=4.46.0", "torch", "peft", "bitsandbytes", "accelerate", "datasets", "tqdm", "protobuf", "sentencepiece", "mistral-common>=1.5.0", "huggingface_hub"]
# ///

"""
MBPP Evaluation: Base Devstral vs Fine-tuned Alizee-Coder
Runs on HF Jobs with GPU support

VERSION: 3.0 - Proper code extraction for both base and fine-tuned models
FIXED:
- Extract code from ```python blocks for base model (handles chat-like responses)
- Function renaming before test execution for both models
"""

import os
import re
import json
import torch
from transformers import AutoTokenizer, AutoModelForCausalLM, BitsAndBytesConfig
from peft import PeftModel
from datasets import load_dataset
from tqdm import tqdm
from huggingface_hub import HfApi

print("=" * 60)
print("EVALUATION: Devstral-Small vs Alizee-Coder-Devstral")
print("Benchmark: MBPP (Mostly Basic Python Problems)")
print("VERSION: Fixed function name extraction")
print("=" * 60)

# Configuration
BASE_MODEL = "mistralai/Devstral-Small-2505"
FINETUNED_ADAPTER = "stmasson/alizee-coder-devstral-1-small"
OUTPUT_REPO = "stmasson/alizee-coder-devstral-1-small"
TEMPERATURE = 0.1
MAX_NEW_TOKENS = 512

# Check GPU
print(f"\nGPU available: {torch.cuda.is_available()}")
if torch.cuda.is_available():
    print(f"GPU: {torch.cuda.get_device_name(0)}")
    print(f"Memory: {torch.cuda.get_device_properties(0).total_memory / 1e9:.1f} GB")

# 4-bit quantization config
bnb_config = BitsAndBytesConfig(
    load_in_4bit=True,
    bnb_4bit_quant_type="nf4",
    bnb_4bit_compute_dtype=torch.bfloat16,
    bnb_4bit_use_double_quant=True,
)

def load_mbpp():
    """Load MBPP dataset"""
    print("\nLoading MBPP dataset...")
    # Load the sanitized version (cleaner test cases)
    dataset = load_dataset("google-research-datasets/mbpp", "sanitized", split="test")
    print(f"Loaded {len(dataset)} problems")
    return dataset

def load_model(model_name, adapter_name=None):
    """Load model with optional LoRA adapter"""
    print(f"\nLoading model: {model_name}")
    if adapter_name:
        print(f"With adapter: {adapter_name}")

    tokenizer = AutoTokenizer.from_pretrained(model_name, trust_remote_code=True)
    if tokenizer.pad_token is None:
        tokenizer.pad_token = tokenizer.eos_token

    model = AutoModelForCausalLM.from_pretrained(
        model_name,
        quantization_config=bnb_config,
        device_map="auto",
        trust_remote_code=True,
        torch_dtype=torch.bfloat16,
    )

    if adapter_name:
        print("Loading LoRA adapter...")
        model = PeftModel.from_pretrained(model, adapter_name)
        model = model.merge_and_unload()
        print("Adapter merged")

    model.eval()
    return model, tokenizer

def extract_function_name(test_list):
    """Extract expected function name from test cases"""
    if not test_list:
        return None

    # Try to find function call in first test case
    # Pattern: assert function_name(...) or function_name(...)
    test = test_list[0]

    # Match: assert func_name( or just func_name(
    patterns = [
        r'assert\s+(\w+)\s*\(',  # assert func_name(
        r'^\s*(\w+)\s*\(',       # func_name( at start
    ]

    for pattern in patterns:
        match = re.search(pattern, test)
        if match:
            func_name = match.group(1)
            # Skip common non-function names
            if func_name not in ['assert', 'print', 'len', 'str', 'int', 'float', 'list', 'dict', 'set', 'tuple']:
                return func_name

    return None

def extract_python_code(text):
    """Extract Python code from model output"""
    # Try ```python blocks
    pattern = r'```python\s*(.*?)\s*```'
    matches = re.findall(pattern, text, re.DOTALL)
    if matches:
        return matches[-1].strip()

    # Try ``` blocks
    pattern = r'```\s*(.*?)\s*```'
    matches = re.findall(pattern, text, re.DOTALL)
    if matches:
        return matches[-1].strip()

    return text.strip()

def generate_completion_base(model, tokenizer, prompt, func_name=None):
    """Generate code completion for BASE model (handles both pure completion and chat-like responses)"""
    # Use a simple code completion prompt
    if func_name:
        code_prompt = f"# Task: {prompt}\n# Write a Python function named {func_name}\n\n"
    else:
        code_prompt = f"# Task: {prompt}\n\n"

    inputs = tokenizer(code_prompt, return_tensors="pt", truncation=True, max_length=2048).to(model.device)

    with torch.no_grad():
        outputs = model.generate(
            **inputs,
            max_new_tokens=MAX_NEW_TOKENS,
            temperature=TEMPERATURE,
            do_sample=True if TEMPERATURE > 0 else False,
            pad_token_id=tokenizer.pad_token_id,
            eos_token_id=tokenizer.eos_token_id,
        )

    completion = tokenizer.decode(outputs[0][inputs['input_ids'].shape[1]:], skip_special_tokens=True)

    # Try to extract code from ```python blocks (if model generates chat-like response)
    code = extract_python_code(completion)

    # If no code block found, try to find a function definition directly
    if not code.startswith("def "):
        # Look for function definition in the raw completion
        match = re.search(r'(def\s+\w+\s*\([^)]*\).*?)(?=\ndef |\nclass |\n```|\Z)', completion, re.DOTALL)
        if match:
            code = match.group(1).strip()

    # Stop at function boundary
    stop_tokens = ["\ndef ", "\nclass ", "\nif __name__", "\n\n\n"]
    for stop in stop_tokens:
        if stop in code:
            code = code[:code.index(stop)]

    return code

def generate_completion_finetuned(model, tokenizer, prompt, func_name=None):
    """Generate code completion for FINE-TUNED model (Instruct format)"""
    # Include expected function name in prompt
    if func_name:
        instruct_prompt = f"<s>[INST] Solve this programming problem with detailed reasoning:\n\n{prompt}\n\nIMPORTANT: The function MUST be named `{func_name}`.\n[/INST]"
    else:
        instruct_prompt = f"<s>[INST] Solve this programming problem with detailed reasoning:\n\n{prompt}\n[/INST]"

    inputs = tokenizer(instruct_prompt, return_tensors="pt", truncation=True, max_length=2048).to(model.device)

    with torch.no_grad():
        outputs = model.generate(
            **inputs,
            max_new_tokens=MAX_NEW_TOKENS * 2,  # More tokens for reasoning
            temperature=TEMPERATURE,
            do_sample=True if TEMPERATURE > 0 else False,
            pad_token_id=tokenizer.pad_token_id,
            eos_token_id=tokenizer.eos_token_id,
        )

    full_response = tokenizer.decode(outputs[0][inputs['input_ids'].shape[1]:], skip_special_tokens=True)
    code = extract_python_code(full_response)

    # If function name was specified but model used different name, try to rename
    if func_name and code:
        # Find the actual function name in generated code
        match = re.search(r'def\s+(\w+)\s*\(', code)
        if match and match.group(1) != func_name:
            # Replace the function name
            code = re.sub(r'def\s+' + re.escape(match.group(1)) + r'\s*\(', f'def {func_name}(', code)

    return code

def evaluate_model(model, tokenizer, dataset, model_name, is_finetuned=False):
    """Evaluate model on MBPP"""
    print(f"\nEvaluating {model_name}...")
    samples = []

    for i, problem in enumerate(tqdm(dataset, desc=f"Generating ({model_name})")):
        task_id = problem.get("task_id", i)
        prompt = problem["prompt"]  # Natural language description
        test_list = problem.get("test_list", [])

        # Extract expected function name from test cases
        func_name = extract_function_name(test_list)

        try:
            if is_finetuned:
                completion = generate_completion_finetuned(model, tokenizer, prompt, func_name)
            else:
                completion = generate_completion_base(model, tokenizer, prompt, func_name)

            samples.append({
                "task_id": task_id,
                "prompt": prompt[:200],
                "completion": completion,
                "test_list": test_list,
                "expected_func": func_name,
                "model": model_name
            })
        except Exception as e:
            print(f"Error on task {task_id}: {e}")
            samples.append({
                "task_id": task_id,
                "prompt": prompt[:200],
                "completion": "# Error during generation",
                "test_list": test_list,
                "expected_func": func_name,
                "model": model_name
            })

    return samples

def run_tests(code, test_list):
    """Run test cases on generated code with automatic function renaming"""
    try:
        # Extract expected function name from first test
        expected_func = extract_function_name(test_list)

        # If we found an expected name, rename the function in code
        if expected_func and code:
            # Find the actual function name in generated code
            match = re.search(r'def\s+(\w+)\s*\(', code)
            if match:
                actual_func = match.group(1)
                if actual_func != expected_func:
                    # Rename the function to match expected name
                    code = re.sub(r'\b' + re.escape(actual_func) + r'\b', expected_func, code)

        # Create execution environment
        exec_globals = {}
        exec(code, exec_globals)

        # Run each test
        for test in test_list:
            try:
                exec(test, exec_globals)
            except AssertionError:
                return False
            except Exception:
                return False
        return True
    except Exception:
        return False

def evaluate_samples(samples):
    """Evaluate samples by running test cases"""
    results = {"passed": 0, "failed": 0, "error": 0}
    detailed = []

    for sample in samples:
        task_id = sample["task_id"]
        code = sample["completion"]
        test_list = sample.get("test_list", [])

        if not test_list:
            results["error"] += 1
            detailed.append({"task_id": task_id, "status": "no_tests"})
            continue

        # Try to run the tests
        if run_tests(code, test_list):
            results["passed"] += 1
            detailed.append({"task_id": task_id, "status": "passed"})
        else:
            results["failed"] += 1
            detailed.append({"task_id": task_id, "status": "failed"})

    total = results["passed"] + results["failed"]
    pass_rate = results["passed"] / total if total > 0 else 0

    return {
        "pass@1": pass_rate,
        "passed": results["passed"],
        "failed": results["failed"],
        "error": results["error"],
        "total": total,
        "detailed": detailed[:10]
    }

def main():
    # Load dataset
    dataset = load_mbpp()

    results = {}

    # Evaluate base model
    print("\n" + "=" * 60)
    print("EVALUATING BASE MODEL")
    print("=" * 60)
    base_model, base_tokenizer = load_model(BASE_MODEL)
    base_samples = evaluate_model(base_model, base_tokenizer, dataset, "Devstral-Small-Base", is_finetuned=False)
    results["base"] = evaluate_samples(base_samples)
    print(f"\nBase Model Results: pass@1 = {results['base']['pass@1']*100:.2f}%")

    # Free memory
    del base_model
    torch.cuda.empty_cache()

    # Evaluate fine-tuned model
    print("\n" + "=" * 60)
    print("EVALUATING FINE-TUNED MODEL")
    print("=" * 60)
    ft_model, ft_tokenizer = load_model(BASE_MODEL, FINETUNED_ADAPTER)
    ft_samples = evaluate_model(ft_model, ft_tokenizer, dataset, "Alizee-Coder-Devstral", is_finetuned=True)
    results["finetuned"] = evaluate_samples(ft_samples)
    print(f"\nFine-tuned Model Results: pass@1 = {results['finetuned']['pass@1']*100:.2f}%")

    # Summary
    print("\n" + "=" * 60)
    print("COMPARISON SUMMARY - MBPP")
    print("=" * 60)
    print(f"\n{'Model':<40} {'pass@1':>10} {'Passed':>8} {'Failed':>8}")
    print("-" * 70)
    print(f"{'Devstral-Small-2505 (Base)':<40} {results['base']['pass@1']*100:>9.2f}% {results['base']['passed']:>8} {results['base']['failed']:>8}")
    print(f"{'Alizee-Coder-Devstral (Fine-tuned)':<40} {results['finetuned']['pass@1']*100:>9.2f}% {results['finetuned']['passed']:>8} {results['finetuned']['failed']:>8}")

    improvement = (results['finetuned']['pass@1'] - results['base']['pass@1']) * 100
    sign = "+" if improvement >= 0 else ""
    print(f"\n{'Improvement:':<40} {sign}{improvement:>9.2f}%")

    # Save results
    output = {
        "benchmark": "MBPP",
        "base_model": BASE_MODEL,
        "finetuned_model": FINETUNED_ADAPTER,
        "results": {
            "base": {
                "pass@1": float(results['base']['pass@1']),
                "passed": results['base']['passed'],
                "failed": results['base']['failed'],
                "total": results['base']['total']
            },
            "finetuned": {
                "pass@1": float(results['finetuned']['pass@1']),
                "passed": results['finetuned']['passed'],
                "failed": results['finetuned']['failed'],
                "total": results['finetuned']['total']
            },
            "improvement": float(improvement)
        },
        "samples": {
            "base": base_samples[:5],
            "finetuned": ft_samples[:5]
        }
    }

    # Save locally
    with open("eval_results_mbpp.json", "w") as f:
        json.dump(output, f, indent=2)
    print("\nResults saved to eval_results_mbpp.json")

    # Upload results
    try:
        api = HfApi()
        api.upload_file(
            path_or_fileobj="eval_results_mbpp.json",
            path_in_repo="eval_results_mbpp.json",
            repo_id=OUTPUT_REPO,
            repo_type="model",
        )
        print(f"Results uploaded to {OUTPUT_REPO}")
    except Exception as e:
        print(f"Could not upload results: {e}")

    print("\n" + "=" * 60)
    print("EVALUATION COMPLETE")
    print("=" * 60)

if __name__ == "__main__":
    main()