"""
User Interest Profile API routes for Munich News Daily.
Provides endpoints to view and manage user interest profiles.
"""

from flask import Blueprint, request, jsonify
from services.interest_profiling_service import (
    get_user_interests,
    get_top_interests,
    build_interests_from_history,
    decay_user_interests,
    get_interest_statistics,
    delete_user_interests
)

interests_bp = Blueprint('interests', __name__)


@interests_bp.route('/api/interests/<email>', methods=['GET'])
def get_interests(email):
    """
    Get user interest profile.
    
    Args:
        email: Email address of the user
        
    Returns:
        JSON response with user interest profile
    """
    try:
        profile = get_user_interests(email)
        
        if not profile:
            return jsonify({
                'success': False,
                'error': 'User profile not found'
            }), 404
        
        # Remove MongoDB _id field
        if '_id' in profile:
            del profile['_id']
        
        return jsonify({
            'success': True,
            'profile': profile
        }), 200
        
    except Exception as e:
        return jsonify({
            'success': False,
            'error': str(e)
        }), 500


@interests_bp.route('/api/interests/<email>/top', methods=['GET'])
def get_top_user_interests(email):
    """
    Get user's top interests sorted by score.
    
    Query parameters:
        top_n: Number of top interests to return (default: 10)
        
    Args:
        email: Email address of the user
        
    Returns:
        JSON response with top categories and keywords
    """
    try:
        top_n = request.args.get('top_n', 10, type=int)
        
        top_interests = get_top_interests(email, top_n)
        
        return jsonify({
            'success': True,
            'email': email,
            'top_categories': [
                {'category': cat, 'score': score}
                for cat, score in top_interests['top_categories']
            ],
            'top_keywords': [
                {'keyword': kw, 'score': score}
                for kw, score in top_interests['top_keywords']
            ]
        }), 200
        
    except Exception as e:
        return jsonify({
            'success': False,
            'error': str(e)
        }), 500


@interests_bp.route('/api/interests/<email>/rebuild', methods=['POST'])
def rebuild_interests(email):
    """
    Rebuild user interest profile from click history.
    
    Request body (optional):
        {
            "days_lookback": 30  // Number of days of history to analyze
        }
        
    Args:
        email: Email address of the user
        
    Returns:
        JSON response with rebuilt profile
    """
    try:
        data = request.get_json() or {}
        days_lookback = data.get('days_lookback', 30)
        
        # Validate days_lookback
        if not isinstance(days_lookback, int) or days_lookback < 1:
            return jsonify({
                'success': False,
                'error': 'days_lookback must be a positive integer'
            }), 400
        
        profile = build_interests_from_history(email, days_lookback)
        
        # Remove MongoDB _id field
        if '_id' in profile:
            del profile['_id']
        
        return jsonify({
            'success': True,
            'message': f'Profile rebuilt from {days_lookback} days of history',
            'profile': profile
        }), 200
        
    except Exception as e:
        return jsonify({
            'success': False,
            'error': str(e)
        }), 500


@interests_bp.route('/api/interests/decay', methods=['POST'])
def decay_interests():
    """
    Decay interest scores for inactive users.
    
    Request body (optional):
        {
            "decay_factor": 0.95,      // Multiplier for scores (default: 0.95)
            "days_threshold": 7        // Only decay profiles older than N days
        }
        
    Returns:
        JSON response with decay statistics
    """
    try:
        data = request.get_json() or {}
        decay_factor = data.get('decay_factor', 0.95)
        days_threshold = data.get('days_threshold', 7)
        
        # Validate parameters
        if not isinstance(decay_factor, (int, float)) or decay_factor <= 0 or decay_factor > 1:
            return jsonify({
                'success': False,
                'error': 'decay_factor must be between 0 and 1'
            }), 400
        
        if not isinstance(days_threshold, int) or days_threshold < 1:
            return jsonify({
                'success': False,
                'error': 'days_threshold must be a positive integer'
            }), 400
        
        result = decay_user_interests(decay_factor, days_threshold)
        
        return jsonify({
            'success': True,
            'message': f'Decayed interests for profiles older than {days_threshold} days',
            'statistics': result
        }), 200
        
    except Exception as e:
        return jsonify({
            'success': False,
            'error': str(e)
        }), 500


@interests_bp.route('/api/interests/statistics', methods=['GET'])
def get_statistics():
    """
    Get statistics about user interests across all users.
    
    Returns:
        JSON response with interest statistics
    """
    try:
        stats = get_interest_statistics()
        
        return jsonify({
            'success': True,
            'statistics': stats
        }), 200
        
    except Exception as e:
        return jsonify({
            'success': False,
            'error': str(e)
        }), 500


@interests_bp.route('/api/interests/<email>', methods=['DELETE'])
def delete_interests(email):
    """
    Delete user interest profile (GDPR compliance).
    
    Args:
        email: Email address of the user
        
    Returns:
        JSON response with confirmation
    """
    try:
        deleted = delete_user_interests(email)
        
        if not deleted:
            return jsonify({
                'success': False,
                'error': 'User profile not found'
            }), 404
        
        return jsonify({
            'success': True,
            'message': f'Interest profile deleted for {email}'
        }), 200
        
    except Exception as e:
        return jsonify({
            'success': False,
            'error': str(e)
        }), 500