"""Response Validator - Validate AI generated responses"""

import re
from typing import Dict, List, Optional, Tuple
from dataclasses import dataclass
from enum import Enum


class ResponseQuality(Enum):
    """Response quality levels"""

    EXCELLENT = "excellent"
    GOOD = "good"
    ADEQUATE = "adequate"
    POOR = "poor"
    INVALID = "invalid"


@dataclass
class ValidationResult:
    """Validation result container"""

    quality: ResponseQuality
    score: float
    issues: List[str]
    suggestions: List[str]


class ResponseValidator:
    """Validate AI generated code responses"""

    def __init__(self):
        self.min_code_length = 50
        self.max_issues = 3
        self.quality_threshold = 0.6

    def validate(self, response: str, instruction: str) -> ValidationResult:
        """Validate response quality"""
        issues: List[str] = []
        suggestions: List[str] = []
        score = 1.0

        if len(response) < self.min_code_length:
            issues.append("Response too short")
            score -= 0.3

        if not self._contains_code(response):
            issues.append("No code block found in response")
            score -= 0.5

        if not self._is_relevant(response, instruction):
            issues.append("Response may not address the instruction")
            score -= 0.2

        if self._has_obvious_errors(response):
            issues.append("Potential errors detected in code")
            score -= 0.2

        code_blocks = self._extract_code_blocks(response)
        for i, block in enumerate(code_blocks):
            if block_language := self._detect_language(block):
                lang_issues = self._check_language_specific(block, block_language)
                issues.extend([f"Block {i+1}: {issue}" for issue in lang_issues])

        if not issues:
            suggestions.append("Response looks good!")
        else:
            suggestions.append("Consider adding more explanatory comments")

        quality = self._determine_quality(score, issues)

        return ValidationResult(
            quality=quality, score=max(0, score), issues=issues, suggestions=suggestions
        )

    def _contains_code(self, response: str) -> bool:
        """Check if response contains code blocks"""
        return bool(re.search(r"```[\s\S]*?```", response))

    def _is_relevant(self, response: str, instruction: str) -> bool:
        """Check if response is relevant to instruction"""
        instruction_words = set(
            re.findall(r"\b\w+\b", instruction.lower())
        )
        response_words = set(re.findall(r"\b\w+\b", response.lower()))
        overlap = instruction_words & response_words

        return len(overlap) >= min(3, len(instruction_words) * 0.3)

    def _has_obvious_errors(self, response: str) -> bool:
        """Check for obvious code errors"""
        error_patterns = [
            r"undefined\s+variable",
            r"cannot\s+find\s+module",
            r"syntax\s+error",
            r"indentation\s+error",
        ]

        for pattern in error_patterns:
            if re.search(pattern, response, re.IGNORECASE):
                return True

        return False

    def _extract_code_blocks(self, response: str) -> List[str]:
        """Extract all code blocks from response"""
        pattern = r"```[\w]*\n?([\s\S]*?)```"
        matches = re.findall(pattern, response)
        return [match.strip() for match in matches]

    def _detect_language(self, code: str) -> Optional[str]:
        """Detect programming language from code"""
        language_signatures = {
            "python": [r"def\s+\w+\s*\(", r"import\s+\w+", r"if\s+__name__"],
            "javascript": [r"const\s+\w+", r"function\s+\w+\s*\(", r"=>\s*{"],
            "typescript": [r":\s*(string|number|boolean)\b", r"interface\s+\w+"],
            "java": [r"public\s+class\s+\w+", r"System\.out\.println"],
            "sql": [r"SELECT\s+.+\s+FROM", r"INSERT\s+INTO", r"CREATE\s+TABLE"],
            "bash": [r"#!/bin/bash", r"echo\s+", r"\$\w+"],
        }

        for lang, patterns in language_signatures.items():
            if any(re.search(p, code) for p in patterns):
                return lang

        return None

    def _check_language_specific(self, code: str, language: str) -> List[str]:
        """Language-specific validation checks"""
        issues = []

        if language == "python":
            if re.search(r"def\s+\w+\s*\([^)]*$", code):
                issues.append("Missing colon at end of function definition")

        if language == "javascript":
            if re.search(r"const\s+\w+\s*=\s*\w+\s*\+\s*['\"]\s*['\"]", code):
                issues.append("Empty string concatenation detected")

        return issues

    def _determine_quality(
        self, score: float, issues: List[str]
    ) -> ResponseQuality:
        """Determine response quality based on score and issues"""
        if score <= 0:
            return ResponseQuality.INVALID
        elif score >= 0.8 and len(issues) == 0:
            return ResponseQuality.EXCELLENT
        elif score >= 0.6:
            return ResponseQuality.GOOD
        elif score >= 0.4:
            return ResponseQuality.ADEQUATE
        else:
            return ResponseQuality.POOR

    def validate_multiple(
        self, responses: List[str], instruction: str
    ) -> List[ValidationResult]:
        """Validate multiple responses and rank them"""
        results = [self.validate(resp, instruction) for resp in responses]
        return sorted(results, key=lambda r: r.score, reverse=True)