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"""
Personalized Learning Pathway System
Implements adaptive learning capabilities that customize instruction based on comprehensive user profiling
"""

import json
import os
import pandas as pd
import numpy as np
from datetime import datetime, timedelta
from typing import Dict, List, Optional, Tuple
from dataclasses import dataclass, asdict
from collections import defaultdict
import pickle

@dataclass
class UserProfile:
    """User profile data structure"""
    user_id: str
    knowledge_level: Dict[str, float]  # Knowledge level for each topic (0-1)
    learning_style: str  # "visual", "textual", "practical", "mixed"
    learning_pace: str  # "slow", "medium", "fast"
    preferred_topics: List[str]
    weak_areas: List[str]
    strong_areas: List[str]
    test_scores: Dict[str, List[float]]  # Historical test scores
    question_history: List[Dict]  # Question and answer history
    learning_time: Dict[str, float]  # Learning time for each topic (minutes)
    last_activity: str
    total_questions_asked: int
    total_tests_completed: int
    bloom_level_performance: Dict[str, Dict[str, float]]  # Bloom level performance for each topic
    created_at: str
    updated_at: str
    # Cold start related fields
    has_completed_onboarding: bool = False  # Whether onboarding is completed
    background_experience: str = ""  # Background experience (e.g., "experienced", "beginner", "intermediate")
    learning_goals: List[str] = None  # Learning goals, None requires special handling
    initial_assessment_completed: bool = False  # Whether initial assessment is completed
    initial_knowledge_survey: Dict[str, float] = None  # Initial knowledge survey results, None requires special handling

@dataclass
class LearningPathNode:
    """Learning path node"""
    node_id: str
    topic: str
    bloom_level: str  # "remember", "understand", "apply", "analyze", "evaluate", "create"
    difficulty: float  # 0-1
    prerequisites: List[str]  # Prerequisite node IDs
    estimated_time: int  # Estimated time (minutes)
    content_type: str  # "reading", "quiz", "practical", "review"
    status: str  # "pending", "in_progress", "completed", "skipped"
    completion_date: Optional[str] = None
    score: Optional[float] = None

@dataclass
class LearningPath:
    """Learning path"""
    path_id: str
    user_id: str
    nodes: List[LearningPathNode]
    current_node_index: int
    completion_percentage: float
    created_at: str
    updated_at: str
    estimated_total_time: int


class UserProfilingSystem:
    """User profiling system"""
    
    def __init__(self, storage_dir: str = "user_data"):
        self.storage_dir = storage_dir
        os.makedirs(storage_dir, exist_ok=True)
        self.profiles_file = os.path.join(storage_dir, "user_profiles.json")
        self.profiles = self._load_profiles()
    
    def _load_profiles(self) -> Dict[str, UserProfile]:
        """Load user profiles"""
        if os.path.exists(self.profiles_file):
            try:
                with open(self.profiles_file, 'r', encoding='utf-8') as f:
                    data = json.load(f)
                    return {uid: UserProfile(**profile) for uid, profile in data.items()}
            except Exception as e:
                print(f"Error loading profiles: {e}")
        return {}
    
    def _save_profiles(self):
        """Save user profiles"""
        try:
            with open(self.profiles_file, 'w', encoding='utf-8') as f:
                data = {uid: asdict(profile) for uid, profile in self.profiles.items()}
                json.dump(data, f, indent=2, ensure_ascii=False)
        except Exception as e:
            print(f"Error saving profiles: {e}")
    
    def get_or_create_profile(self, user_id: str) -> UserProfile:
        """Get or create user profile (cold start)"""
        if user_id not in self.profiles:
            self.profiles[user_id] = UserProfile(
                user_id=user_id,
                knowledge_level={},
                learning_style="mixed",
                learning_pace="medium",
                preferred_topics=[],
                weak_areas=[],
                strong_areas=[],
                test_scores={},
                question_history=[],
                learning_time={},
                last_activity=datetime.now().isoformat(),
                total_questions_asked=0,
                total_tests_completed=0,
                bloom_level_performance={},
                created_at=datetime.now().isoformat(),
                updated_at=datetime.now().isoformat(),
                has_completed_onboarding=False,
                background_experience="",
                learning_goals=None,
                initial_assessment_completed=False,
                initial_knowledge_survey=None
            )
            self._save_profiles()
        return self.profiles[user_id]
    
    def is_cold_start(self, user_id: str) -> bool:
        """Check if user is in cold start state"""
        if user_id not in self.profiles:
            return True
        profile = self.profiles[user_id]
        return not profile.has_completed_onboarding
    
    def complete_onboarding(self, user_id: str, onboarding_data: Dict):
        """Complete cold start setup and collect initial user information
        
        Information collected during cold start:
        1. Learning preferences:
           - learning_style: Learning style preference
           - learning_pace: Learning pace preference
        2. Background information:
           - background_experience: Background experience
           - learning_goals: List of learning goals
        3. Initial knowledge assessment:
           - initial_knowledge_survey: Initial familiarity with each topic (0-1)
           - initial_assessment_completed: Whether initial assessment is completed
        """
        profile = self.get_or_create_profile(user_id)
        
        # Update learning style
        if 'learning_style' in onboarding_data:
            profile.learning_style = onboarding_data['learning_style']
        
        # Update learning pace
        if 'learning_pace' in onboarding_data:
            profile.learning_pace = onboarding_data['learning_pace']
        
        # Update background experience
        if 'background_experience' in onboarding_data:
            profile.background_experience = onboarding_data['background_experience']
        
        # Update learning goals
        if 'learning_goals' in onboarding_data:
            profile.learning_goals = onboarding_data['learning_goals']
        
        # Update initial knowledge survey
        if 'initial_knowledge_survey' in onboarding_data:
            profile.initial_knowledge_survey = onboarding_data['initial_knowledge_survey']
            # Convert initial survey results to knowledge level
            profile.knowledge_level = onboarding_data['initial_knowledge_survey'].copy()
        
        # Update preferred topics (based on initial survey, select topics with lower familiarity)
        if 'initial_knowledge_survey' in onboarding_data:
            survey = onboarding_data['initial_knowledge_survey']
            # Select topics with lower familiarity as learning focus
            low_knowledge_topics = [topic for topic, level in survey.items() if level < 0.5]
            profile.preferred_topics = low_knowledge_topics[:3]  # Take top 3
        
        # Update initial assessment status
        if 'initial_assessment_completed' in onboarding_data:
            profile.initial_assessment_completed = onboarding_data['initial_assessment_completed']
        
        # Mark cold start as completed
        profile.has_completed_onboarding = True
        profile.updated_at = datetime.now().isoformat()
        
        self._save_profiles()
        return profile
    
    def update_from_test_results(self, user_id: str, topic: str, test_results: List[Dict]):
        """Update user profile from test results"""
        profile = self.get_or_create_profile(user_id)
        
        # Calculate average score
        scores = [r.get('score', 1.0 if r.get('is_correct', False) else 0.0) 
                  for r in test_results]
        avg_score = np.mean(scores) if scores else 0.5
        
        # Update knowledge level
        if topic not in profile.knowledge_level:
            profile.knowledge_level[topic] = avg_score
        else:
            # Weighted average (give more weight to latest results)
            profile.knowledge_level[topic] = 0.7 * avg_score + 0.3 * profile.knowledge_level[topic]
        
        # Update test score history
        if topic not in profile.test_scores:
            profile.test_scores[topic] = []
        profile.test_scores[topic].append(avg_score)
        
        # Update Bloom level performance
        if topic not in profile.bloom_level_performance:
            profile.bloom_level_performance[topic] = {}
        
        for result in test_results:
            level = result.get('level', 'unknown')
            is_correct = result.get('is_correct', False)
            score = 1.0 if is_correct else 0.0
            
            if level not in profile.bloom_level_performance[topic]:
                profile.bloom_level_performance[topic][level] = []
            profile.bloom_level_performance[topic][level].append(score)
        
        # Calculate average performance for each Bloom level
        for level in profile.bloom_level_performance[topic]:
            scores = profile.bloom_level_performance[topic][level]
            profile.bloom_level_performance[topic][level] = np.mean(scores) if scores else 0.0
        
        # Update weak and strong areas
        self._update_weak_strong_areas(profile)
        
        # Update learning pace
        profile.learning_pace = self._calculate_learning_pace(profile)
        
        profile.total_tests_completed += 1
        profile.last_activity = datetime.now().isoformat()
        profile.updated_at = datetime.now().isoformat()
        
        self._save_profiles()
        return profile
    
    def update_from_question(self, user_id: str, question: str, topic: Optional[str] = None):
        """Update user profile from question history"""
        profile = self.get_or_create_profile(user_id)
        
        profile.question_history.append({
            "question": question,
            "topic": topic,
            "timestamp": datetime.now().isoformat()
        })
        
        # Analyze question type to infer learning style
        profile.learning_style = self._infer_learning_style(profile.question_history)
        
        # Update preferred topics
        if topic:
            if topic not in profile.preferred_topics:
                profile.preferred_topics.append(topic)
            # Sort by frequency
            topic_counts = defaultdict(int)
            for q in profile.question_history:
                if q.get('topic'):
                    topic_counts[q['topic']] += 1
            profile.preferred_topics = sorted(topic_counts.items(), key=lambda x: x[1], reverse=True)[:5]
            profile.preferred_topics = [t[0] for t in profile.preferred_topics]
        
        profile.total_questions_asked += 1
        profile.last_activity = datetime.now().isoformat()
        profile.updated_at = datetime.now().isoformat()
        
        self._save_profiles()
        return profile
    
    def update_learning_time(self, user_id: str, topic: str, minutes: float):
        """Update learning time"""
        profile = self.get_or_create_profile(user_id)
        
        if topic not in profile.learning_time:
            profile.learning_time[topic] = 0.0
        profile.learning_time[topic] += minutes
        
        profile.last_activity = datetime.now().isoformat()
        profile.updated_at = datetime.now().isoformat()
        
        self._save_profiles()
        return profile
    
    def _update_weak_strong_areas(self, profile: UserProfile):
        """Update weak and strong areas"""
        # Topics with knowledge level below 0.6 are weak areas
        weak = [topic for topic, level in profile.knowledge_level.items() if level < 0.6]
        # Topics with knowledge level above 0.8 are strong areas
        strong = [topic for topic, level in profile.knowledge_level.items() if level >= 0.8]
        
        profile.weak_areas = weak
        profile.strong_areas = strong
    
    def _calculate_learning_pace(self, profile: UserProfile) -> str:
        """Calculate learning pace"""
        if not profile.test_scores:
            return "medium"
        
        # Calculate test completion speed
        total_tests = profile.total_tests_completed
        if total_tests == 0:
            return "medium"
        
        # Analyze performance changes in recent tests
        recent_scores = []
        for topic_scores in profile.test_scores.values():
            if topic_scores:
                recent_scores.extend(topic_scores[-3:])  # Last 3 tests
        
        if not recent_scores:
            return "medium"
        
        # If recent scores improve quickly, likely a fast-paced learner
        if len(recent_scores) >= 3:
            improvement = recent_scores[-1] - recent_scores[0]
            if improvement > 0.3:
                return "fast"
            elif improvement < -0.1:
                return "slow"
        
        return "medium"
    
    def _infer_learning_style(self, question_history: List[Dict]) -> str:
        """Infer learning style from question history"""
        if not question_history:
            return "mixed"
        
        # Analyze question keywords
        visual_keywords = ["how", "what does", "show", "visual", "diagram", "illustration"]
        practical_keywords = ["how to", "step", "procedure", "activate", "use", "operate"]
        textual_keywords = ["what is", "explain", "define", "describe", "meaning"]
        
        visual_count = sum(1 for q in question_history 
                          if any(kw in q.get('question', '').lower() for kw in visual_keywords))
        practical_count = sum(1 for q in question_history 
                             if any(kw in q.get('question', '').lower() for kw in practical_keywords))
        textual_count = sum(1 for q in question_history 
                           if any(kw in q.get('question', '').lower() for kw in textual_keywords))
        
        total = len(question_history)
        if total == 0:
            return "mixed"
        
        visual_ratio = visual_count / total
        practical_ratio = practical_count / total
        textual_ratio = textual_count / total
        
        max_ratio = max(visual_ratio, practical_ratio, textual_ratio)
        if max_ratio > 0.4:
            if visual_ratio == max_ratio:
                return "visual"
            elif practical_ratio == max_ratio:
                return "practical"
            else:
                return "textual"
        
        return "mixed"
    
    def get_profile_summary(self, user_id: str) -> Dict:
        """Get user profile summary"""
        profile = self.get_or_create_profile(user_id)
        
        return {
            "user_id": profile.user_id,
            "knowledge_level": profile.knowledge_level,
            "learning_style": profile.learning_style,
            "learning_pace": profile.learning_pace,
            "preferred_topics": profile.preferred_topics,
            "weak_areas": profile.weak_areas,
            "strong_areas": profile.strong_areas,
            "total_questions": profile.total_questions_asked,
            "total_tests": profile.total_tests_completed,
            "overall_progress": self._calculate_overall_progress(profile)
        }
    
    def _calculate_overall_progress(self, profile: UserProfile) -> float:
        """Calculate overall progress"""
        if not profile.knowledge_level:
            return 0.0
        return np.mean(list(profile.knowledge_level.values()))


class LearningPathGenerator:
    """Learning path generator"""
    
    def __init__(self, user_profiling: UserProfilingSystem, available_topics: List[str]):
        self.user_profiling = user_profiling
        self.available_topics = available_topics
        self.bloom_levels = ["remember", "understand", "apply", "analyze", "evaluate", "create"]
    
    def generate_path(self, user_id: str, focus_areas: Optional[List[str]] = None) -> LearningPath:
        """Generate personalized learning path"""
        profile = self.user_profiling.get_or_create_profile(user_id)
        
        # Determine topics to learn
        topics_to_learn = self._determine_topics(profile, focus_areas)
        
        # Generate learning nodes
        nodes = []
        node_id_counter = 0
        
        for topic in topics_to_learn:
            topic_level = profile.knowledge_level.get(topic, 0.0)
            bloom_performance = profile.bloom_level_performance.get(topic, {})
            
            # Generate nodes for different Bloom levels for each topic
            for bloom_level in self.bloom_levels:
                # Check if this node is needed
                if not self._needs_node(profile, topic, bloom_level, topic_level, bloom_performance):
                    continue
                
                node = LearningPathNode(
                    node_id=f"node_{node_id_counter}",
                    topic=topic,
                    bloom_level=bloom_level,
                    difficulty=self._calculate_difficulty(topic_level, bloom_level),
                    prerequisites=self._get_prerequisites(nodes, topic, bloom_level),
                    estimated_time=self._estimate_time(bloom_level, profile.learning_pace),
                    content_type=self._determine_content_type(bloom_level, profile.learning_style),
                    status="pending"
                )
                nodes.append(node)
                node_id_counter += 1
        
        # Sort nodes (considering prerequisites)
        ordered_nodes = self._topological_sort(nodes)
        
        # Calculate total time
        total_time = sum(node.estimated_time for node in ordered_nodes)
        
        path = LearningPath(
            path_id=f"path_{user_id}_{datetime.now().strftime('%Y%m%d%H%M%S')}",
            user_id=user_id,
            nodes=ordered_nodes,
            current_node_index=0,
            completion_percentage=0.0,
            created_at=datetime.now().isoformat(),
            updated_at=datetime.now().isoformat(),
            estimated_total_time=total_time
        )
        
        return path
    
    def _determine_topics(self, profile: UserProfile, focus_areas: Optional[List[str]]) -> List[str]:
        """Determine topics to learn"""
        if focus_areas:
            return focus_areas
        
        # Prioritize weak areas
        topics = profile.weak_areas.copy()
        
        # Add unlearned topics
        for topic in self.available_topics:
            if topic not in profile.knowledge_level and topic not in topics:
                topics.append(topic)
        
        # If no weak areas, recommend preferred or strong area related topics
        if not topics:
            topics = profile.preferred_topics[:3] if profile.preferred_topics else self.available_topics[:3]
        
        return topics[:5]  # Limit to maximum 5 topics
    
    def _needs_node(self, profile: UserProfile, topic: str, bloom_level: str, 
                   topic_level: float, bloom_performance: Dict) -> bool:
        """Determine if a node is needed"""
        # If performance at this Bloom level is already good, skip
        level_performance = bloom_performance.get(bloom_level, 0.0)
        if level_performance >= 0.8:
            return False
        
        # Decide based on knowledge level
        if topic_level < 0.3 and bloom_level in ["analyze", "evaluate", "create"]:
            return False  # Insufficient foundational knowledge, learn basics first
        
        return True
    
    def _calculate_difficulty(self, topic_level: float, bloom_level: str) -> float:
        """Calculate node difficulty"""
        bloom_weights = {
            "remember": 0.2,
            "understand": 0.3,
            "apply": 0.5,
            "analyze": 0.7,
            "evaluate": 0.85,
            "create": 1.0
        }
        
        base_difficulty = bloom_weights.get(bloom_level, 0.5)
        # Adjust based on current knowledge level
        adjusted = base_difficulty * (1 - topic_level * 0.3)
        return min(1.0, max(0.1, adjusted))
    
    def _get_prerequisites(self, existing_nodes: List[LearningPathNode], 
                          topic: str, bloom_level: str) -> List[str]:
        """Get prerequisites"""
        prereqs = []
        
        # Lower Bloom levels of the same topic are prerequisites
        bloom_order = ["remember", "understand", "apply", "analyze", "evaluate", "create"]
        current_index = bloom_order.index(bloom_level) if bloom_level in bloom_order else 0
        
        for node in existing_nodes:
            if node.topic == topic:
                node_index = bloom_order.index(node.bloom_level) if node.bloom_level in bloom_order else 0
                if node_index < current_index:
                    prereqs.append(node.node_id)
        
        return prereqs
    
    def _estimate_time(self, bloom_level: str, learning_pace: str) -> int:
        """Estimate learning time (minutes)"""
        base_times = {
            "remember": 10,
            "understand": 15,
            "apply": 20,
            "analyze": 25,
            "evaluate": 30,
            "create": 35
        }
        
        base_time = base_times.get(bloom_level, 20)
        
        pace_multipliers = {
            "slow": 1.5,
            "medium": 1.0,
            "fast": 0.7
        }
        
        return int(base_time * pace_multipliers.get(learning_pace, 1.0))
    
    def _determine_content_type(self, bloom_level: str, learning_style: str) -> str:
        """Determine content type"""
        # Decide based on learning style and Bloom level
        if learning_style == "visual":
            if bloom_level in ["remember", "understand"]:
                return "reading"
            else:
                return "practical"
        elif learning_style == "practical":
            return "practical"
        elif learning_style == "textual":
            return "reading"
        else:
            # mixed
            if bloom_level in ["apply", "analyze", "evaluate", "create"]:
                return "quiz"
            return "reading"
    
    def _topological_sort(self, nodes: List[LearningPathNode]) -> List[LearningPathNode]:
        """Topological sort to ensure prerequisites are completed first"""
        # Create node mapping
        node_map = {node.node_id: node for node in nodes}
        
        # Calculate in-degree
        in_degree = {node.node_id: len(node.prerequisites) for node in nodes}
        
        # Find nodes without prerequisites
        queue = [node.node_id for node in nodes if in_degree[node.node_id] == 0]
        result = []
        
        while queue:
            current_id = queue.pop(0)
            current_node = node_map[current_id]
            result.append(current_node)
            
            # Update in-degree of other nodes
            for node in nodes:
                if current_id in node.prerequisites:
                    in_degree[node.node_id] -= 1
                    if in_degree[node.node_id] == 0:
                        queue.append(node.node_id)
        
        # Add remaining nodes (may have circular dependencies)
        remaining = [node for node in nodes if node not in result]
        result.extend(remaining)
        
        return result


class AdaptiveLearningEngine:
    """Adaptive learning engine"""
    
    def __init__(self, user_profiling: UserProfilingSystem, learning_path_generator: LearningPathGenerator):
        self.user_profiling = user_profiling
        self.learning_path_generator = learning_path_generator
        self.paths_file = os.path.join("user_data", "learning_paths.json")
        self.paths = self._load_paths()
    
    def _load_paths(self) -> Dict[str, LearningPath]:
        """Load learning paths"""
        if os.path.exists(self.paths_file):
            try:
                with open(self.paths_file, 'r', encoding='utf-8') as f:
                    data = json.load(f)
                    paths = {}
                    for pid, path_data in data.items():
                        nodes = [LearningPathNode(**node) for node in path_data['nodes']]
                        path = LearningPath(
                            path_id=path_data['path_id'],
                            user_id=path_data['user_id'],
                            nodes=nodes,
                            current_node_index=path_data['current_node_index'],
                            completion_percentage=path_data['completion_percentage'],
                            created_at=path_data['created_at'],
                            updated_at=path_data['updated_at'],
                            estimated_total_time=path_data['estimated_total_time']
                        )
                        paths[pid] = path
                    return paths
            except Exception as e:
                print(f"Error loading paths: {e}")
        return {}
    
    def _save_paths(self):
        """Save learning paths"""
        try:
            os.makedirs("user_data", exist_ok=True)
            with open(self.paths_file, 'w', encoding='utf-8') as f:
                data = {}
                for pid, path in self.paths.items():
                    path_dict = asdict(path)
                    data[pid] = path_dict
                json.dump(data, f, indent=2, ensure_ascii=False)
        except Exception as e:
            print(f"Error saving paths: {e}")
    
    def create_or_update_path(self, user_id: str, focus_areas: Optional[List[str]] = None) -> LearningPath:
        """Create or update learning path"""
        # Check if there is an active path
        active_path = self.get_active_path(user_id)
        
        if active_path and active_path.completion_percentage < 1.0:
            # Update existing path
            return self._update_path(active_path)
        else:
            # Create new path
            path = self.learning_path_generator.generate_path(user_id, focus_areas)
            self.paths[path.path_id] = path
            self._save_paths()
            return path
    
    def get_active_path(self, user_id: str) -> Optional[LearningPath]:
        """Get user's current active path"""
        user_paths = [p for p in self.paths.values() if p.user_id == user_id]
        if not user_paths:
            return None
        
        # Return the latest incomplete path
        active = [p for p in user_paths if p.completion_percentage < 1.0]
        if active:
            return max(active, key=lambda p: p.created_at)
        
        # If no incomplete paths, return the latest one
        return max(user_paths, key=lambda p: p.created_at)
    
    def complete_node(self, user_id: str, node_id: str, score: float):
        """Complete a node"""
        path = self.get_active_path(user_id)
        if not path:
            return None
        
        # Find node and mark as completed
        for node in path.nodes:
            if node.node_id == node_id:
                node.status = "completed"
                node.score = score
                node.completion_date = datetime.now().isoformat()
                break
        
        # Update path progress
        completed = sum(1 for n in path.nodes if n.status == "completed")
        path.completion_percentage = completed / len(path.nodes) if path.nodes else 0.0
        
        # Update current node index
        for i, node in enumerate(path.nodes):
            if node.status not in ["completed", "skipped"]:
                path.current_node_index = i
                break
        
        path.updated_at = datetime.now().isoformat()
        self._save_paths()
        
        # Update user profile
        current_node = path.nodes[path.current_node_index] if path.current_node_index < len(path.nodes) else None
        if current_node:
            self.user_profiling.update_learning_time(
                user_id, 
                current_node.topic, 
                current_node.estimated_time
            )
        
        return path
    
    def _update_path(self, path: LearningPath) -> LearningPath:
        """Update path based on user performance"""
        profile = self.user_profiling.get_or_create_profile(path.user_id)
        
        # Check if path needs adjustment
        for node in path.nodes:
            if node.status == "pending":
                # Check if already mastered
                topic_level = profile.knowledge_level.get(node.topic, 0.0)
                bloom_perf = profile.bloom_level_performance.get(node.topic, {}).get(node.bloom_level, 0.0)
                
                if bloom_perf >= 0.8:
                    # Already mastered, can skip
                    node.status = "skipped"
                    node.completion_date = datetime.now().isoformat()
        
        # Recalculate progress
        completed = sum(1 for n in path.nodes if n.status in ["completed", "skipped"])
        path.completion_percentage = completed / len(path.nodes) if path.nodes else 0.0
        
        path.updated_at = datetime.now().isoformat()
        self._save_paths()
        
        return path
    
    def get_recommendations(self, user_id: str) -> Dict:
        """Get learning recommendations"""
        profile = self.user_profiling.get_or_create_profile(user_id)
        path = self.get_active_path(user_id)
        
        recommendations = {
            "next_node": None,
            "suggested_topics": [],
            "review_topics": [],
            "challenge_topics": []
        }
        
        # Recommend next node
        if path and path.current_node_index < len(path.nodes):
            next_node = path.nodes[path.current_node_index]
            recommendations["next_node"] = {
                "node_id": next_node.node_id,
                "topic": next_node.topic,
                "bloom_level": next_node.bloom_level,
                "content_type": next_node.content_type,
                "estimated_time": next_node.estimated_time
            }
        
        # Recommend topics for review
        recommendations["review_topics"] = profile.weak_areas[:3]
        
        # Recommend challenge topics (advanced content for strong areas)
        for topic in profile.strong_areas[:2]:
            if topic not in recommendations["challenge_topics"]:
                recommendations["challenge_topics"].append(topic)
        
        # Recommend new topics
        all_topics = set(self.learning_path_generator.available_topics)
        learned_topics = set(profile.knowledge_level.keys())
        new_topics = list(all_topics - learned_topics)[:3]
        recommendations["suggested_topics"] = new_topics
        
        return recommendations
    
    def get_path_visualization_data(self, user_id: str) -> Dict:
        """Get path visualization data"""
        path = self.get_active_path(user_id)
        if not path:
            return {"nodes": [], "edges": []}
        
        nodes_data = []
        edges_data = []
        
        for node in path.nodes:
            nodes_data.append({
                "id": node.node_id,
                "topic": node.topic,
                "bloom_level": node.bloom_level,
                "status": node.status,
                "difficulty": node.difficulty,
                "score": node.score
            })
            
            # Add edges (prerequisites)
            for prereq_id in node.prerequisites:
                edges_data.append({
                    "source": prereq_id,
                    "target": node.node_id
                })
        
        return {
            "nodes": nodes_data,
            "edges": edges_data,
            "completion_percentage": path.completion_percentage,
            "current_node_index": path.current_node_index
        }