import re
from typing import Dict, Tuple, Optional

def extract_solution(solution_str):
    # Split response to isolate assistant output
    if "Assistant:" in solution_str:
        processed_str = solution_str.split("Assistant:", 1)[1]
    elif "<|im_start|>assistant" in solution_str:
        processed_str = solution_str.split("<|im_start|>assistant", 1)[1]
    elif "[/INST]" in solution_str:
        processed_str = solution_str.split("[/INST]", 1)[1]
    else:
        print("[Error] Failed to locate model response header")
        return None, solution_str

    # Extract final answer using XML-style tags
    answer_pattern = r'<answer>(.*?)</answer>'
    matches = list(re.finditer(answer_pattern, processed_str, re.DOTALL))

    if not matches:
        print("[Error] No valid answer tags found")
        return None, processed_str

    final_answer = matches[-1].group(1).strip()

    # format1_match = re.search(r"([a-zA-Z]):", final_answer)
    format1_match = re.findall(r'(?:^|\s)([A-Za-z])(?=[:.])', final_answer, re.MULTILINE)
    format2_match = re.findall(r'(yes|no)', final_answer.lower())
    format3_match = re.findall(r'[A-Z]', final_answer.upper())
    if format1_match:
        # return format1_match.group(1).strip(), processed_str
        return ','.join(format1_match), processed_str
    elif format2_match:
        return format2_match[-1].strip(), processed_str
    elif format3_match:
        return ",".join(format3_match), processed_str
    return final_answer.replace(", ", ","), processed_str


def validate_response_structure(processed_str: str) -> bool:
    """Performs comprehensive validation of response structure.
    
    Args:
        processed_str: Processed response string from the model
        
    Returns:
        Boolean indicating whether all formatting requirements are met
    """
    print("\n[Structure Validation]")
    validation_passed = True

    # Check required tags
    tags = {
        'think_start': ('<think>', 1),
        'think_end': ('</think>', 1),
        'answer_start': ('<answer>', 1),
        'answer_end': ('</answer>', 1)
    }

    positions = {}
    for tag_name, (tag_str, expected_count) in tags.items():
        count = processed_str.count(tag_str)
        positions[tag_name] = pos = processed_str.find(tag_str)

        print(f"  {tag_str}: count={count}, position={pos}")

        if count != expected_count:
            print(f"  [Error] {tag_str} appears {count} times (expected {expected_count})")
            validation_passed = False

    # Verify tag order
    if (positions['think_start'] > positions['think_end'] or
        positions['think_end'] > positions['answer_start'] or
        positions['answer_start'] > positions['answer_end']):
        print("  [Error] Incorrect tag order: Expected <think>...</think><answer>...</answer>")
        validation_passed = False
    else:
        print("  Tag sequence validation passed")

    return validation_passed

def parse_ground_truth_text_format(ground_truth):
    answer_pattern = r'<answer>(.*?)</answer>'
    matches = list(re.finditer(answer_pattern, ground_truth, re.DOTALL))
    if ":" in ground_truth and "[{" in ground_truth:
        return ground_truth
    elif ":" in ground_truth:
        format1_match = re.search(r"([a-zA-Z]):", ground_truth)
        if format1_match:
            return format1_match.group(1).strip()
        else:
            return ground_truth
    elif matches:
        return matches[-1].group(1).strip()
    else:
        return ground_truth

def compute_score(solution_str: str, ground_truth: str, method='strict', format_reward: int = 1, answer_reward: float = 1.0):
    """Computes comprehensive score for model response.
    
    Args:
        solution_str: Raw model response string
        ground_truth: Dictionary containing ground truth data
        method: the method to extract the solution, choices are 'strict' and 'flexible'
        format_reward: Points awarded/deducted for format correctness
        answer_reward: Points awarded/deducted for answer correctness
        
    Returns:
        Total score (sum of format and answer rewards)
    """
    print("\n" + "="*80)
    print(" Processing New Sample ".center(80, '='))
    print(f"[Ground Truth]: {ground_truth}")
    ground_truth = parse_ground_truth_text_format(ground_truth)

    # Extract model answer
    answer_text, processed_str=extract_solution(solution_str=solution_str)
    print(f"\n[Model Response]\n{processed_str}")
    print(f"\n[Processed Model Response]\n{answer_text}")

   # Validate response structure
    format_correct = validate_response_structure(processed_str)
    format_score = format_reward if format_correct else -abs(format_reward)
    print(f"\n  Format validation: {'PASS' if format_correct else 'FAIL'}")
    print(f"  Format score: {format_score}")
  
    # Validate answer content
    answer_score = 0
    if format_correct and answer_text:
        print(f"\n[Content Validation]")
        print(f"  Expected: {ground_truth}")
        print(f"  Predicted: {answer_text}")
        if answer_text.casefold() == ground_truth.casefold():
            answer_score = 2       
            print("  Content validation: FULL MATCH")
        else:
            answer_score = -1.5
            print("  Content validation: MISMATCH")
    else:
        answer_score = -2
        print("\n[Content Validation] Skipped due to format errors or missing answer")

    total_score = format_score + answer_score
    print("\n" + "-"*80)
    print(f" Final Score ".center(80, '-'))
    print(f"  Format: {format_score}")
    print(f"  Answer: {answer_score}")
    print(f"  Total: {total_score}")
    print("="*80 + "\n")

    return total_score