"""
Knowledge Graph Agent with GraphRAG

Manages the user's knowledge graph using GraphRAG:
- Nodes: concepts, doubts, topics, resources
- Edges: relationships, dependencies, associations
- GraphRAG for retrieval and generation
"""

from typing import Dict, List, Any, Optional
from dataclasses import dataclass, field
from datetime import datetime
import json


@dataclass
class GraphNode:
    """Knowledge graph node"""
    node_id: str
    node_type: str
    label: str
    properties: Dict = field(default_factory=dict)
    embeddings: Optional[List[float]] = None
    created_at: datetime = field(default_factory=datetime.now)


@dataclass
class GraphEdge:
    """Knowledge graph edge"""
    edge_id: str
    source_id: str
    target_id: str
    relation_type: str
    weight: float = 1.0
    properties: Dict = field(default_factory=dict)
    created_at: datetime = field(default_factory=datetime.now)


@dataclass
class Ontology:
    """Domain ontology for topic structure"""
    entity_types: List[Dict] = field(default_factory=list)
    relation_types: List[Dict] = field(default_factory=list)


class KnowledgeGraphAgent:
    """
    Agent that manages the knowledge graph with GraphRAG capabilities.
    
    Features:
    - Entity extraction from doubts and notes
    - Relationship discovery
    - Graph-based retrieval
    - Path finding between concepts
    - Ontology generation
    """
    
    def __init__(self, user_id: str, config: Optional[Dict] = None):
        self.user_id = user_id
        self.config = config or {}
        
        self.nodes: Dict[str, GraphNode] = {}
        self.edges: Dict[str, GraphEdge] = {}
        
        self.graph_id = f"cf_graph_{user_id}_{datetime.now().timestamp()}"
        
        self._initialize_default_ontology()
    
    def _initialize_default_ontology(self):
        """Initialize default learning ontology"""
        self.ontology = Ontology(
            entity_types=[
                {'name': 'Concept', 'description': 'A learning concept or topic'},
                {'name': 'Doubt', 'description': 'A question or confusion point'},
                {'name': 'Resource', 'description': 'Learning resource or material'},
                {'name': 'Topic', 'description': 'Main subject area'},
                {'name': 'Skill', 'description': 'Developed skill or competency'}
            ],
            relation_types=[
                {'name': 'prerequisite_of', 'description': 'Is prerequisite for'},
                {'name': 'related_to', 'description': 'Is related to'},
                {'name': 'part_of', 'description': 'Is part of'},
                {'name': 'helps_understand', 'description': 'Helps understand'},
                {'name': 'contrasts_with', 'description': 'Contrasts with'}
            ]
        )
    
    def add_doubt_to_graph(self, doubt_data: Dict) -> GraphNode:
        """Add a captured doubt to the knowledge graph"""
        node_id = f"doubt_{doubt_data.get('id', datetime.now().timestamp())}"
        
        concept_tags = doubt_data.get('conceptTags', [])
        
        node = GraphNode(
            node_id=node_id,
            node_type='Doubt',
            label=doubt_data.get('formattedTitle', doubt_data.get('rawText', '')),
            properties={
                'raw_text': doubt_data.get('rawText', ''),
                'summary': doubt_data.get('formattedSummary', ''),
                'doubt_type': doubt_data.get('doubtType', 'concept'),
                'concepts': concept_tags,
                'url': doubt_data.get('page', {}).get('url', ''),
                'mastered': doubt_data.get('mastered', False),
                'review_count': doubt_data.get('reviewCount', 0)
            }
        )
        
        self.nodes[node_id] = node
        
        for concept in concept_tags:
            self._ensure_concept_node(concept)
            self._add_edge(
                source=concept,
                target=node_id,
                relation='part_of'
            )
        
        return node
    
    def _ensure_concept_node(self, concept: str) -> GraphNode:
        """Ensure a concept node exists in the graph"""
        concept_id = f"concept_{concept.lower().replace(' ', '_')}"
        
        if concept_id in self.nodes:
            return self.nodes[concept_id]
        
        node = GraphNode(
            node_id=concept_id,
            node_type='Concept',
            label=concept,
            properties={
                'mastery_level': 0.0,
                'importance': 0.5,
                'last_reviewed': None
            }
        )
        
        self.nodes[concept_id] = node
        return node
    
    def _add_edge(
        self, 
        source: str, 
        target: str, 
        relation: str,
        weight: float = 1.0
    ) -> GraphEdge:
        """Add an edge between nodes"""
        edge_id = f"edge_{source}_{target}_{relation}"
        
        source_id = f"concept_{source.lower().replace(' ', '_')}" if not source.startswith('concept_') else source
        target_id = f"concept_{target.lower().replace(' ', '_')}" if not target.startswith('concept_') else target
        
        if source_id not in self.nodes or target_id not in self.nodes:
            return None
        
        edge = GraphEdge(
            edge_id=edge_id,
            source_id=source_id,
            target_id=target_id,
            relation_type=relation,
            weight=weight
        )
        
        self.edges[edge_id] = edge
        return edge
    
    def add_resource(self, resource_data: Dict) -> GraphNode:
        """Add a learning resource to the graph"""
        node_id = f"resource_{resource_data.get('id', datetime.now().timestamp())}"
        
        node = GraphNode(
            node_id=node_id,
            node_type='Resource',
            label=resource_data.get('title', 'Untitled Resource'),
            properties={
                'url': resource_data.get('url', ''),
                'type': resource_data.get('type', 'webpage'),
                'topics': resource_data.get('topics', []),
                'difficulty': resource_data.get('difficulty', 0.5)
            }
        )
        
        self.nodes[node_id] = node
        
        for topic in resource_data.get('topics', []):
            self._ensure_concept_node(topic)
            self._add_edge(topic, node_id, 'part_of')
        
        return node
    
    def add_topic(self, topic: str, parent: Optional[str] = None) -> GraphNode:
        """Add a topic node to the graph"""
        node = self._ensure_concept_node(topic)
        
        if parent:
            self._ensure_concept_node(parent)
            self._add_edge(topic, parent, 'prerequisite_of')
        
        return node
    
    def graphrag_retrieve(
        self, 
        query: str, 
        top_k: int = 5
    ) -> List[Dict]:
        """
        GraphRAG retrieval - find relevant nodes based on query.
        
        Uses:
        - Keyword matching
        - Graph traversal
        - Relationship scoring
        """
        results = []
        
        query_lower = query.lower()
        query_terms = query_lower.split()
        
        for node_id, node in self.nodes.items():
            score = 0.0
            
            label_lower = node.label.lower()
            for term in query_terms:
                if term in label_lower:
                    score += 1.0
                if term in str(node.properties).lower():
                    score += 0.5
            
            if node.node_type == 'Doubt' and 'mastered' in node.properties:
                if node.properties['mastered']:
                    score *= 0.8
            
            if score > 0:
                results.append({
                    'node': node,
                    'score': score,
                    'matched_terms': [t for t in query_terms if t in label_lower]
                })
        
        results.sort(key=lambda x: x['score'], reverse=True)
        
        return [{
            'node_id': r['node'].node_id,
            'type': r['node'].node_type,
            'label': r['node'].label,
            'properties': r['node'].properties,
            'score': r['score'],
            'related': self._get_related_nodes(r['node'].node_id, limit=3)
        } for r in results[:top_k]]
    
    def _get_related_nodes(self, node_id: str, limit: int = 3) -> List[Dict]:
        """Get related nodes through graph traversal"""
        related = []
        
        for edge_id, edge in self.edges.items():
            if edge.source_id == node_id:
                target = self.nodes.get(edge.target_id)
                if target:
                    related.append({
                        'node_id': target.node_id,
                        'type': target.node_type,
                        'label': target.label,
                        'relation': edge.relation_type
                    })
            elif edge.target_id == node_id:
                source = self.nodes.get(edge.source_id)
                if source:
                    related.append({
                        'node_id': source.node_id,
                        'type': source.node_type,
                        'label': source.label,
                        'relation': edge.relation_type
                    })
        
        return related[:limit]
    
    def find_learning_path(
        self, 
        from_topic: str, 
        to_topic: str
    ) -> List[str]:
        """Find shortest path between two topics using BFS"""
        from_id = f"concept_{from_topic.lower().replace(' ', '_')}"
        to_id = f"concept_{to_topic.lower().replace(' ', '_')}"
        
        if from_id not in self.nodes or to_id not in self.nodes:
            return []
        
        queue = [(from_id, [from_id])]
        visited = {from_id}
        
        while queue:
            current, path = queue.pop(0)
            
            if current == to_id:
                return [self.nodes[n].label for n in path]
            
            for edge_id, edge in self.edges.items():
                neighbor = None
                if edge.source_id == current:
                    neighbor = edge.target_id
                elif edge.target_id == current:
                    neighbor = edge.source_id
                
                if neighbor and neighbor not in visited:
                    visited.add(neighbor)
                    queue.append((neighbor, path + [neighbor]))
        
        return []
    
    def get_topic_mastery(self) -> Dict[str, float]:
        """Calculate mastery level for each topic"""
        mastery = {}
        
        for node_id, node in self.nodes.items():
            if node.node_type == 'Concept':
                related_doubts = self._get_doubt_count(node_id)
                total_doubts = len([n for n in self.nodes.values() if n.node_type == 'Doubt'])
                
                if total_doubts > 0:
                    mastery[node.label] = 1.0 - (related_doubts / total_doubts)
                else:
                    mastery[node.label] = 0.0
        
        return mastery
    
    def _get_doubt_count(self, concept_id: str) -> int:
        """Get number of doubts associated with a concept"""
        count = 0
        for edge_id, edge in self.edges.items():
            if edge.source_id == concept_id and edge.relation_type == 'part_of':
                target = self.nodes.get(edge.target_id)
                if target and target.node_type == 'Doubt':
                    count += 1
        return count
    
    def get_graph_stats(self) -> Dict:
        """Get graph statistics"""
        node_types = {}
        for node in self.nodes.values():
            node_types[node.node_type] = node_types.get(node.node_type, 0) + 1
        
        relation_types = {}
        for edge in self.edges.values():
            relation_types[edge.relation_type] = relation_types.get(edge.relation_type, 0) + 1
        
        return {
            'graph_id': self.graph_id,
            'total_nodes': len(self.nodes),
            'total_edges': len(self.edges),
            'node_types': node_types,
            'relation_types': relation_types,
            'mastery': self.get_topic_mastery()
        }
    
    def export_graph(self) -> Dict:
        """Export graph for persistence"""
        return {
            'graph_id': self.graph_id,
            'nodes': [
                {
                    'node_id': n.node_id,
                    'node_type': n.node_type,
                    'label': n.label,
                    'properties': n.properties
                }
                for n in self.nodes.values()
            ],
            'edges': [
                {
                    'edge_id': e.edge_id,
                    'source_id': e.source_id,
                    'target_id': e.target_id,
                    'relation_type': e.relation_type,
                    'weight': e.weight
                }
                for e in self.edges.values()
            ],
            'ontology': {
                'entity_types': self.ontology.entity_types,
                'relation_types': self.ontology.relation_types
            }
        }
    
    def import_graph(self, graph_data: Dict):
        """Import graph from persistence"""
        self.graph_id = graph_data.get('graph_id', self.graph_id)
        
        self.nodes.clear()
        self.edges.clear()
        
        for node_data in graph_data.get('nodes', []):
            node = GraphNode(
                node_id=node_data['node_id'],
                node_type=node_data['node_type'],
                label=node_data['label'],
                properties=node_data.get('properties', {})
            )
            self.nodes[node.node_id] = node
        
        for edge_data in graph_data.get('edges', []):
            edge = GraphEdge(
                edge_id=edge_data['edge_id'],
                source_id=edge_data['source_id'],
                target_id=edge_data['target_id'],
                relation_type=edge_data['relation_type'],
                weight=edge_data.get('weight', 1.0)
            )
            self.edges[edge.edge_id] = edge
    
    async def sync_to_zep(self):
        """Sync graph to Zep Cloud for advanced GraphRAG"""
        pass
    
    async def sync_to_graph(self):
        """Sync current state"""
        pass