#!/usr/bin/env python3
"""
Deterministic Evaluation Controls

Provides utilities for ensuring reproducible and deterministic evaluation results
across different runs and environments.
"""

import logging
import os
import random
from dataclasses import dataclass, field
from typing import Any, Dict, List, Optional

logger = logging.getLogger(__name__)

# Default seed for reproducible evaluations
DEFAULT_EVALUATION_SEED = 42


@dataclass
class DeterministicConfig:
    """Configuration for deterministic evaluation settings."""

    # Random seed for reproducibility
    random_seed: int = DEFAULT_EVALUATION_SEED

    # Sort results for consistent ordering
    sort_results: bool = True

    # Use fixed precision for floating point comparisons
    float_precision: int = 6

    # Consistent evaluation order
    consistent_order: bool = True

    # Additional deterministic flags
    deterministic_mode: bool = True

    # Environment variables to set for reproducibility
    env_vars: Dict[str, str] = field(
        default_factory=lambda: {
            "PYTHONHASHSEED": "0",
            "CUBLAS_WORKSPACE_CONFIG": ":4096:8",
        }
    )


class DeterministicEvaluator:
    """
    Wrapper that ensures deterministic evaluation behavior.

    Provides:
    - Fixed random seeds
    - Consistent result ordering
    - Reproducible floating point precision
    - Environment variable controls
    """

    def __init__(self, config: Optional[DeterministicConfig] = None):
        """Initialize deterministic evaluator with configuration."""
        self.config = config or DeterministicConfig()
        self._setup_deterministic_environment()

    def _setup_deterministic_environment(self) -> None:
        """Configure environment for deterministic behavior."""
        # Set random seed
        random.seed(self.config.random_seed)

        # Set environment variables for reproducibility
        for key, value in self.config.env_vars.items():
            os.environ[key] = value

        # Try to set numpy seed if available
        try:
            import numpy as np

            np.random.seed(self.config.random_seed)
        except ImportError:
            logger.warning("numpy is not installed; deterministic seeding for numpy will be skipped.")

        # Try to set torch seed if available
        try:
            import torch

            torch.manual_seed(self.config.random_seed)
            if torch.cuda.is_available():
                torch.cuda.manual_seed(self.config.random_seed)
                torch.cuda.manual_seed_all(self.config.random_seed)
            # Enable deterministic algorithms in PyTorch
            torch.use_deterministic_algorithms(True, warn_only=True)
        except ImportError:
            # torch is optional; skip deterministic seeding if not installed
            pass

        logger.info(f"Deterministic environment configured with seed: {self.config.random_seed}")

    def normalize_float(self, value: float) -> float:
        """Normalize floating point value to consistent precision."""
        return round(value, self.config.float_precision)

    def normalize_metrics(self, metrics: Dict[str, Any]) -> Dict[str, Any]:
        """Normalize metric values for consistent precision."""
        normalized = {}
        for key, value in metrics.items():
            if isinstance(value, float):
                normalized[key] = self.normalize_float(value)
            elif isinstance(value, dict):
                normalized[key] = self.normalize_metrics(value)
            else:
                normalized[key] = value
        return normalized

    def sort_evaluation_results(
        self, results: List[Dict[str, Any]], sort_key: str = "query_id"
    ) -> List[Dict[str, Any]]:
        """Sort evaluation results for consistent ordering."""
        if not self.config.sort_results:
            return results

        try:
            return sorted(results, key=lambda x: x.get(sort_key, ""))
        except (KeyError, TypeError):
            # Fallback to string representation if sort key issues
            return sorted(results, key=str)

    def ensure_deterministic_order(self, items: List[Any], key_func=None) -> List[Any]:
        """Ensure consistent ordering of items."""
        if not self.config.consistent_order:
            return items

        if key_func:
            return sorted(items, key=key_func)

        # Try natural sorting, fall back to string representation
        try:
            return sorted(items)
        except TypeError:
            return sorted(items, key=str)


def create_deterministic_groundedness_evaluator(seed: Optional[int] = None) -> DeterministicEvaluator:
    """Create a deterministic evaluator specifically configured for groundedness evaluation."""
    config = DeterministicConfig(
        random_seed=seed or DEFAULT_EVALUATION_SEED,
        sort_results=True,
        float_precision=4,  # Slightly lower precision for groundedness scores
        consistent_order=True,
        deterministic_mode=True,
    )
    return DeterministicEvaluator(config)


def evaluate_groundedness_deterministic(
    generated_text: str, source_passages: List[str], evaluator: Optional[DeterministicEvaluator] = None
) -> Dict[str, float]:
    """
    Evaluate groundedness with deterministic behavior.

    Uses token overlap and passage-level matching with consistent ordering
    and normalized precision.
    """
    if evaluator is None:
        evaluator = create_deterministic_groundedness_evaluator()

    if not generated_text.strip() or not source_passages:
        return evaluator.normalize_metrics(
            {"groundedness_score": 0.0, "passage_coverage": 0.0, "token_overlap": 0.0, "exact_matches": 0.0}
        )

    # Normalize inputs for consistent processing
    generated_tokens = set(generated_text.lower().split())

    # Process passages in consistent order
    sorted_passages = evaluator.ensure_deterministic_order(source_passages)

    # Calculate passage-level scores
    passage_scores = []
    total_coverage = 0
    exact_matches = 0

    for passage in sorted_passages:
        if not passage.strip():
            continue

        passage_tokens = set(passage.lower().split())

        # Token overlap for this passage
        if passage_tokens:
            overlap = len(generated_tokens & passage_tokens) / len(passage_tokens)
            passage_scores.append(overlap)

            # Check for exact phrase matches (deterministic substring matching)
            passage_lower = passage.lower()
            generated_lower = generated_text.lower()

            # Count exact matches using consistent methodology
            exact_phrases = []
            words = generated_lower.split()

            for i in range(len(words)):
                for j in range(i + 2, min(i + 8, len(words) + 1)):  # 2-7 word phrases
                    phrase = " ".join(words[i:j])
                    if phrase in passage_lower and phrase not in exact_phrases:
                        exact_phrases.append(phrase)

            if exact_phrases:
                exact_matches += 1

            total_coverage += overlap

    # Calculate aggregate scores with normalization
    if passage_scores:
        groundedness_score = sum(passage_scores) / len(passage_scores)
        passage_coverage = total_coverage / len(sorted_passages)
    else:
        groundedness_score = 0.0
        passage_coverage = 0.0

    # Overall token overlap across all passages
    all_source_tokens = set()
    for passage in sorted_passages:
        all_source_tokens.update(passage.lower().split())

    if all_source_tokens:
        token_overlap = len(generated_tokens & all_source_tokens) / len(all_source_tokens)
    else:
        token_overlap = 0.0

    exact_match_rate = exact_matches / len(sorted_passages) if sorted_passages else 0.0

    metrics = {
        "groundedness_score": groundedness_score,
        "passage_coverage": passage_coverage,
        "token_overlap": token_overlap,
        "exact_matches": exact_match_rate,
    }

    return evaluator.normalize_metrics(metrics)


def evaluate_citation_accuracy_deterministic(
    generated_text: str,
    returned_sources: List[Dict[str, Any]],
    expected_sources: List[str],
    evaluator: Optional[DeterministicEvaluator] = None,
) -> Dict[str, float]:
    """
    Evaluate citation accuracy with deterministic behavior.

    Provides consistent filename matching and source validation.
    """
    if evaluator is None:
        evaluator = create_deterministic_groundedness_evaluator()

    if not expected_sources:
        # If no expected sources, score based on whether any sources were returned
        return evaluator.normalize_metrics(
            {
                "citation_accuracy": 1.0 if not returned_sources else 0.0,
                "source_precision": 1.0,
                "source_recall": 1.0,
                "exact_filename_matches": 1.0,
            }
        )

    # Normalize filenames for consistent matching
    def normalize_filename(filename: str) -> str:
        """Normalize filename for consistent comparison."""
        if not filename:
            return ""

        import os
        import re

        # Remove query parameters and fragments
        filename = re.sub(r"[?#].*$", "", filename.strip())

        # Get basename
        basename = os.path.basename(filename)

        # Remove common extensions consistently
        basename = re.sub(
            r"\.(md|markdown|txt|html|htm|pdf|csv|json|yaml|yml|py|ipynb)$", "", basename, flags=re.IGNORECASE
        )

        return basename.lower()

    # Extract returned filenames in consistent order
    returned_filenames = set()
    sorted_sources = evaluator.ensure_deterministic_order(returned_sources, key_func=str)

    for source in sorted_sources:
        if isinstance(source, dict):
            candidates = [source.get(k) for k in ["filename", "source_file", "file", "url", "path", "source"]]
            # Check metadata
            metadata = source.get("metadata", {})
            if isinstance(metadata, dict):
                candidates.extend([metadata.get(k) for k in ["filename", "file", "source_file"]])
        else:
            candidates = [str(source)]

        for candidate in candidates:
            if candidate:
                normalized = normalize_filename(str(candidate))
                if normalized:
                    returned_filenames.add(normalized)

    # Normalize expected sources
    expected_normalized = set()
    sorted_expected = evaluator.ensure_deterministic_order(expected_sources)

    for expected in sorted_expected:
        normalized = normalize_filename(str(expected))
        if normalized:
            expected_normalized.add(normalized)

    # Calculate matches with consistent methodology
    exact_matches = len(expected_normalized & returned_filenames)

    # Calculate precision and recall
    if returned_filenames:
        precision = exact_matches / len(returned_filenames)
    else:
        precision = 1.0 if not expected_normalized else 0.0

    if expected_normalized:
        recall = exact_matches / len(expected_normalized)
    else:
        recall = 1.0

    # Overall citation accuracy (F1-like score)
    if precision + recall > 0:
        citation_accuracy = 2 * (precision * recall) / (precision + recall)
    else:
        citation_accuracy = 0.0

    exact_filename_match_rate = recall  # Same as recall for exact matches

    metrics = {
        "citation_accuracy": citation_accuracy,
        "source_precision": precision,
        "source_recall": recall,
        "exact_filename_matches": exact_filename_match_rate,
    }

    return evaluator.normalize_metrics(metrics)


# Utility functions for integration
def setup_deterministic_evaluation(seed: Optional[int] = None) -> DeterministicEvaluator:
    """Setup deterministic evaluation environment."""
    return create_deterministic_groundedness_evaluator(seed)


def get_evaluation_seed() -> int:
    """Get the evaluation seed from environment or use default."""
    try:
        return int(os.getenv("EVALUATION_SEED", DEFAULT_EVALUATION_SEED))
    except (ValueError, TypeError):
        return DEFAULT_EVALUATION_SEED