"""
Doubt Solver - Resolves student questions using Chain-of-Thought reasoning
"""

from typing import Tuple, Dict
from config import LLM_PROVIDER
from core.llm_engine import LLMEngine
from core.prompt_builder import PromptBuilder
from core.validator import InputValidator, ContentValidator
from core.utils import log_event, truncate_text
import re


class DoubtSolver:
    """Solves student doubts using step-by-step reasoning."""
    
    def __init__(self, llm_provider: str = LLM_PROVIDER):
        """
        Initialize doubt solver.
        
        Args:
            llm_provider: LLM provider to use
        """
        self.engine = LLMEngine(llm_provider)
        self.prompt_builder = PromptBuilder()
        self.validator = InputValidator()
    
    def solve(
        self,
        question: str,
        context: str = "",
        mode: str = "normal",
        use_cot: bool = True
    ) -> Tuple[bool, str]:
        """
        Solve a student's doubt with reasoning.
        
        Args:
            question: Student's doubt/question
            context: Relevant material context
            mode: Response mode
            use_cot: Use Chain-of-Thought reasoning
        
        Returns:
            Tuple of (success, solution)
        """
        # Validate input
        is_valid, msg = self.validator.validate_input(question)
        if not is_valid:
            log_event("VALIDATION_ERROR", f"DoubtSolver: {msg}")
            return False, msg
        
        # Build prompt
        try:
            prompt = self.prompt_builder.build_doubt_solver_prompt(
                question,
                context=truncate_text(context, 3000) if context else "",
                mode=mode
            )
            
            if use_cot:
                # Add Chain-of-Thought emphasis
                prompt = f"""{prompt}

IMPORTANT: Use Chain-of-Thought reasoning.
1. Break down the question into parts
2. Think through each part step by step
3. Show your reasoning clearly
4. Verify your answer
5. Provide the final answer
"""
            
            log_event("PROMPT_BUILT", "Doubt solver prompt ready")
        except Exception as e:
            log_event("PROMPT_ERROR", f"Error building doubt solver: {str(e)}")
            return False, f"Error: {str(e)}"
        
        # Generate solution
        success, solution = self.engine.generate(prompt, max_tokens=2000)
        
        if not success:
            log_event("DOUBT_SOLVER_ERROR", solution)
            return False, solution
        
        # Quality check
        is_meaningful = ContentValidator.is_meaningful_response(solution, min_words=20)
        if not is_meaningful:
            log_event("QUALITY_CHECK_FAILED", "Solution too short")
            return False, "Response too short. Please try again."
        
        quality_score = ContentValidator.estimate_quality(solution)
        log_event("QUALITY_SCORE", f"Solution quality: {quality_score:.2f}")
        
        log_event("DOUBT_SOLVED", f"Solution provided")
        return True, solution
    
    def parse_solution(self, solution_text: str) -> Dict:
        """
        Parse solution into structured components.
        
        Args:
            solution_text: Raw solution text
        
        Returns:
            Dictionary with thinking, answer, insights
        """
        parsed = {
            "thinking": "",
            "answer": "",
            "insights": "",
            "raw_text": solution_text
        }
        
        # Extract THINKING section
        thinking_match = re.search(
            r'(?:THINKING|Step|Reasoning):\s*(.+?)(?=ANSWER|Final|$)',
            solution_text,
            re.IGNORECASE | re.DOTALL
        )
        if thinking_match:
            parsed["thinking"] = thinking_match.group(1).strip()
        
        # Extract ANSWER section
        answer_match = re.search(
            r'(?:ANSWER|Final Answer):\s*(.+?)(?=INSIGHTS|Additional|$)',
            solution_text,
            re.IGNORECASE | re.DOTALL
        )
        if answer_match:
            parsed["answer"] = answer_match.group(1).strip()
        else:
            # If no explicit answer, use last paragraph
            paragraphs = solution_text.split('\n\n')
            if paragraphs:
                parsed["answer"] = paragraphs[-1].strip()
        
        # Extract INSIGHTS section
        insights_match = re.search(
            r'(?:INSIGHTS|Additional|Tips):\s*(.+?)$',
            solution_text,
            re.IGNORECASE | re.DOTALL
        )
        if insights_match:
            parsed["insights"] = insights_match.group(1).strip()
        
        return parsed
    
    def solve_with_context(
        self,
        question: str,
        context: str,
        mode: str = "normal"
    ) -> Tuple[bool, str]:
        """
        Solve doubt with full context from notes.
        
        Args:
            question: Student's question
            context: Full context from notes
            mode: Response mode
        
        Returns:
            Tuple of (success, solution)
        """
        return self.solve(question, context=context, mode=mode)
    
    def solve_step_by_step(self, question: str) -> Tuple[bool, str]:
        """
        Solve doubt with emphasis on step-by-step reasoning.
        
        Args:
            question: Student's question
        
        Returns:
            Tuple of (success, solution)
        """
        enhanced_prompt = f"""Solve this doubt step by step.

Student's Question: {question}

Your approach:
1. Clarify what's being asked
2. Identify key concepts
3. Work through it step by step
4. Check your reasoning
5. Provide clear final answer

Use this format:
STEP 1: [First step]
STEP 2: [Second step]
...
FINAL ANSWER: [Clear answer]

Now solve:"""
        
        try:
            success, solution = self.engine.generate(enhanced_prompt, max_tokens=2000)
            return success, solution
        except Exception as e:
            return False, f"Error: {str(e)}"
    
    def compare_solutions(
        self,
        question: str,
        modes: list = None
    ) -> Tuple[bool, Dict]:
        """
        Compare solutions in different modes.
        
        Args:
            question: Question to solve
            modes: List of modes to compare
        
        Returns:
            Tuple of (success, dict of solutions)
        """
        if modes is None:
            modes = ["normal", "detailed", "teacher"]
        
        solutions = {}
        
        for mode in modes:
            success, solution = self.solve(question, mode=mode)
            solutions[mode] = solution if success else f"Error: {solution}"
        
        return True, solutions
    
    def is_question_valid(self, question: str) -> Tuple[bool, str]:
        """
        Check if question is valid and answerable.
        
        Args:
            question: Question to validate
        
        Returns:
            Tuple of (is_valid, message)
        """
        if len(question.strip()) < 5:
            return False, "Question too short"
        
        if len(question.strip().split()) < 3:
            return False, "Question not detailed enough"
        
        return True, "Valid question"