"""
SPARQL Reasoner Module

This module provides SPARQL-based reasoning capabilities for knowledge graph
query answering, including query expansion, inference rule integration, and
query optimization.

Key Features:
    - SPARQL query reasoning and execution
    - Inference rule integration
    - Query optimization and caching
    - Query expansion
    - Performance optimization
    - Error handling and recovery
    - Triplet store integration

Main Classes:
    - SPARQLReasoner: SPARQL-based reasoning engine
    - SPARQLQueryResult: Dataclass for SPARQL query results

Example Usage:
    >>> from semantica.reasoning import SPARQLReasoner
    >>> reasoner = SPARQLReasoner()
    >>> query = "SELECT ?s ?p ?o WHERE { ?s ?p ?o }"
    >>> result = reasoner.query(query)
    >>> expanded = reasoner.expand_query(query, rules)

Author: Semantica Contributors
License: MIT
"""

import re
from dataclasses import dataclass, field
from typing import Any, Dict, List, Optional, Set

from ..utils.exceptions import ProcessingError, ValidationError
from ..utils.logging import get_logger
from ..utils.progress_tracker import get_progress_tracker
from .reasoner import Rule, Reasoner


@dataclass
class SPARQLQueryResult:
    """SPARQL query result."""

    bindings: List[Dict[str, Any]]
    variables: List[str]
    metadata: Dict[str, Any] = field(default_factory=dict)


class SPARQLReasoner:
    """
    SPARQL-based reasoning engine.

    • SPARQL query reasoning and execution
    • Inference rule integration
    • Query optimization and caching
    • Performance optimization
    • Error handling and recovery
    • Advanced SPARQL features
    """

    def __init__(self, config: Optional[Dict[str, Any]] = None, **kwargs):
        """
        Initialize SPARQL reasoner.

        Args:
            config: Configuration dictionary
            **kwargs: Additional configuration options:
                - triplet_store: Triplet store connection
                - enable_inference: Enable inference rules
        """
        self.logger = get_logger("sparql_reasoner")
        self.config = config or {}
        self.config.update(kwargs)

        # Initialize progress tracker
        self.progress_tracker = get_progress_tracker()
        # Ensure progress tracker is enabled
        if not self.progress_tracker.enabled:
            self.progress_tracker.enabled = True

        self.reasoner = Reasoner(**self.config)
        self.triplet_store = self.config.get("triplet_store")
        self.enable_inference = self.config.get("enable_inference", True)

        self.query_cache: Dict[str, Any] = {}

    def expand_query(self, query: str, **options) -> str:
        """
        Expand SPARQL query with inference rules.

        Args:
            query: Original SPARQL query
            **options: Additional options

        Returns:
            Expanded query
        """
        tracking_id = self.progress_tracker.start_tracking(
            module="reasoning",
            submodule="SPARQLReasoner",
            message="Expanding SPARQL query with inference rules",
        )

        try:
            if not self.enable_inference:
                self.progress_tracker.stop_tracking(
                    tracking_id,
                    status="completed",
                    message="Inference disabled, returning original query",
                )
                return query

            # Parse query to find patterns
            self.progress_tracker.update_tracking(
                tracking_id, message="Parsing query patterns..."
            )
            expanded_query = query

            # Get inference rules
            self.progress_tracker.update_tracking(
                tracking_id, message="Getting inference rules..."
            )
            rules = self.reasoner.rules

            # Add inferred patterns based on rules
            self.progress_tracker.update_tracking(
                tracking_id,
                message=f"Converting {len(rules)} rules to SPARQL patterns...",
            )
            for rule in rules:
                # Convert rule to SPARQL pattern
                sparql_pattern = self._rule_to_sparql(rule)
                if sparql_pattern:
                    # Add to query (basic implementation)
                    expanded_query += f"\n# Inference: {rule.name}\n{sparql_pattern}"

            self.progress_tracker.stop_tracking(
                tracking_id,
                status="completed",
                message=f"Expanded query with {len(rules)} inference rules",
            )
            return expanded_query

        except Exception as e:
            self.progress_tracker.stop_tracking(
                tracking_id, status="failed", message=str(e)
            )
            raise

    def _rule_to_sparql(self, rule: Rule) -> Optional[str]:
        """Convert rule to SPARQL pattern."""
        # Basic conversion - can be enhanced
        try:
            # Extract conditions as SPARQL patterns
            patterns = []
            for condition in rule.conditions:
                # Simple pattern matching
                if " is_a " in condition:
                    parts = condition.split(" is_a ")
                    if len(parts) == 2:
                        var = parts[0].strip()
                        if var.startswith("?"):
                            var = var[1:]
                        class_type = parts[1].strip()
                        patterns.append(f"?{var} a :{class_type} .")

            # Conclusion
            if " is_a " in rule.conclusion:
                parts = rule.conclusion.split(" is_a ")
                if len(parts) == 2:
                    var = parts[0].strip()
                    if var.startswith("?"):
                        var = var[1:]
                    class_type = parts[1].strip()
                    conclusion_pattern = f"?{var} a :{class_type} ."

                    # Combine into SPARQL pattern
                    if patterns:
                        return f"{' '.join(patterns)} => {conclusion_pattern}"

        except Exception as e:
            self.logger.warning(f"Could not convert rule to SPARQL: {e}")

        return None

    def infer_results(
        self, query_results: SPARQLQueryResult, **options
    ) -> SPARQLQueryResult:
        """
        Infer additional results from query results.

        Args:
            query_results: Original query results
            **options: Additional options

        Returns:
            Results with inferences
        """
        tracking_id = self.progress_tracker.start_tracking(
            module="reasoning",
            submodule="SPARQLReasoner",
            message="Inferring additional results from query results",
        )

        try:
            inferred_bindings = list(query_results.bindings)

            # Apply inference rules
            if self.enable_inference:
                self.progress_tracker.update_tracking(
                    tracking_id, message="Applying inference rules..."
                )
                rules = self.reasoner.rules

                for rule in rules:
                    # Check if rule can be applied to results
                    new_bindings = self._apply_rule_to_results(
                        rule, query_results.bindings
                    )
                    inferred_bindings.extend(new_bindings)

            # Remove duplicates
            self.progress_tracker.update_tracking(
                tracking_id, message="Removing duplicate bindings..."
            )
            unique_bindings = self._deduplicate_bindings(inferred_bindings)

            inferred_count = len(unique_bindings) - len(query_results.bindings)
            result = SPARQLQueryResult(
                bindings=unique_bindings,
                variables=query_results.variables,
                metadata={
                    **query_results.metadata,
                    "original_count": len(query_results.bindings),
                    "inferred_count": inferred_count,
                },
            )

            self.progress_tracker.stop_tracking(
                tracking_id,
                status="completed",
                message=f"Inferred {inferred_count} additional results",
            )
            return result

        except Exception as e:
            self.progress_tracker.stop_tracking(
                tracking_id, status="failed", message=str(e)
            )
            raise

    def _apply_rule_to_results(
        self, rule: Rule, bindings: List[Dict[str, Any]]
    ) -> List[Dict[str, Any]]:
        """Apply rule to query results."""
        new_bindings = []

        for binding in bindings:
            # Check if rule conditions match
            if self._match_rule_conditions(rule, binding):
                # Generate new binding from conclusion
                new_binding = self._generate_binding_from_conclusion(rule, binding)
                if new_binding:
                    new_bindings.append(new_binding)

        return new_bindings

    def _match_rule_conditions(self, rule: Rule, binding: Dict[str, Any]) -> bool:
        """Check if rule conditions match binding."""
        for condition in rule.conditions:
            # Simple matching - can be enhanced
            if " is_a " in condition:
                parts = condition.split(" is_a ")
                if len(parts) == 2:
                    var = parts[0].strip().replace("?", "")
                    class_type = parts[1].strip()

                    # Check if binding has matching type
                    if var in binding:
                        value = binding[var]
                        # Check type (simplified)
                        if not self._has_type(value, class_type):
                            return False

        return True

    def _has_type(self, value: Any, class_type: str) -> bool:
        """Check if value has type (simplified)."""
        # This is a placeholder - in practice would check against knowledge graph
        return True

    def _generate_binding_from_conclusion(
        self, rule: Rule, binding: Dict[str, Any]
    ) -> Optional[Dict[str, Any]]:
        """Generate new binding from rule conclusion."""
        new_binding = binding.copy()

        # Parse conclusion
        if " is_a " in rule.conclusion:
            parts = rule.conclusion.split(" is_a ")
            if len(parts) == 2:
                var = parts[0].strip().replace("?", "")
                class_type = parts[1].strip()

                # Add type information
                if var in new_binding:
                    new_binding[f"{var}_type"] = class_type

        return new_binding

    def _deduplicate_bindings(
        self, bindings: List[Dict[str, Any]]
    ) -> List[Dict[str, Any]]:
        """Remove duplicate bindings."""
        seen = set()
        unique = []

        for binding in bindings:
            # Create hashable representation
            binding_key = tuple(sorted(binding.items()))
            if binding_key not in seen:
                seen.add(binding_key)
                unique.append(binding)

        return unique

    def execute_query(self, query: str, **options) -> SPARQLQueryResult:
        """
        Execute SPARQL query with reasoning.

        Args:
            query: SPARQL query string
            **options: Additional options

        Returns:
            Query results
        """
        tracking_id = self.progress_tracker.start_tracking(
            module="reasoning",
            submodule="SPARQLReasoner",
            message="Executing SPARQL query with reasoning",
        )

        try:
            # Check cache
            self.progress_tracker.update_tracking(
                tracking_id, message="Checking query cache..."
            )
            if query in self.query_cache:
                self.logger.debug("Returning cached query result")
                self.progress_tracker.stop_tracking(
                    tracking_id,
                    status="completed",
                    message="Returned cached query result",
                )
                return self.query_cache[query]

            # Expand query
            self.progress_tracker.update_tracking(
                tracking_id, message="Expanding query with inference rules..."
            )
            expanded_query = self.expand_query(query, **options)

            # Execute query (if triplet store available)
            self.progress_tracker.update_tracking(
                tracking_id, message="Executing query..."
            )
            if self.triplet_store:
                # This would call the triplet store's query method
                # For now, return empty result
                result = SPARQLQueryResult(bindings=[], variables=[])
            else:
                # Mock result for testing
                result = SPARQLQueryResult(bindings=[], variables=[])

            # Infer additional results
            if self.enable_inference:
                self.progress_tracker.update_tracking(
                    tracking_id, message="Inferring additional results..."
                )
                result = self.infer_results(result, **options)

            # Cache result
            self.progress_tracker.update_tracking(
                tracking_id, message="Caching query result..."
            )
            self.query_cache[query] = result

            self.progress_tracker.stop_tracking(
                tracking_id,
                status="completed",
                message=f"Query executed: {len(result.bindings)} results",
            )
            return result

        except Exception as e:
            self.progress_tracker.stop_tracking(
                tracking_id, status="failed", message=str(e)
            )
            raise

    def clear_cache(self) -> None:
        """Clear query cache."""
        self.query_cache.clear()

    def add_inference_rule(self, rule_definition: str, **options) -> Rule:
        """Add inference rule."""
        return self.reasoner.add_rule(rule_definition)
