import os
import json
from flask import Blueprint, render_template, request, redirect, url_for, flash, jsonify, current_app
from flask_login import LoginManager, UserMixin, login_user, login_required, logout_user, current_user
from werkzeug.security import check_password_hash, generate_password_hash
from core.db import get_db_connection

auth_bp = Blueprint('auth', __name__)

login_manager = LoginManager()
login_manager.login_view = 'auth.login'

class User(UserMixin):
    def __init__(self, id, username):
        self.id = id
        self.username = username

@login_manager.user_loader
def load_user(user_id):
    with get_db_connection() as conn:
        user = conn.execute('SELECT id, username FROM users WHERE id = ?', (user_id,)).fetchone()
    return User(user[0], user[1]) if user else None

@auth_bp.route('/login', methods=['GET', 'POST'])
def login():
    if request.method == 'POST':
        user_in = request.form.get('username')
        pass_in = request.form.get('password')
        with get_db_connection() as conn:
            user = conn.execute('SELECT * FROM users WHERE username = ?', (user_in,)).fetchone()
        if user and check_password_hash(user[2], pass_in):
            login_user(User(user[0], user[1]))
            return redirect(url_for('inventory.inventory'))
        flash('Invalid credentials.')
    return render_template('login.html')

@auth_bp.route('/logout')
@login_required
def logout():
    logout_user()
    return redirect(url_for('auth.login'))

@auth_bp.route('/settings/update', methods=['POST'])
@login_required
def update_settings():
    new_password = request.form.get('password')
    profile_pic = request.form.get('profile_pic')
    
    with get_db_connection() as conn:
        if new_password and len(new_password) > 0:
            hashed_pw = generate_password_hash(new_password)
            conn.execute('UPDATE users SET password = ? WHERE id = ?', (hashed_pw, current_user.id))
        
        if profile_pic:
            conn.execute('UPDATE users SET profile_pic = ? WHERE id = ?', (profile_pic, current_user.id))
        conn.commit()
    
    flash('Configuración actualizada')
    return redirect(request.referrer)

@auth_bp.route('/api/instance/config')
@login_required
def get_instance_config():
    db_dir = os.path.dirname(current_app.config.get('DB_FILE', ''))
    instance_file = os.path.join(db_dir, 'instance.json')
    if os.path.exists(instance_file):
        with open(instance_file) as f:
            config = json.load(f)
    else:
        config = {}
    return jsonify({
        "instance_id": config.get('instance_id', ''),
        "display_name": config.get('display_name', 'Caja Principal'),
        "server_url": config.get('server_url', ''),
        "sync_secret": config.get('sync_secret', ''),
        "mode": config.get('mode', 'desktop')
    })

@auth_bp.route('/api/instance/config', methods=['POST'])
@login_required
def save_instance_config():
    data = request.get_json()
    db_dir = os.path.dirname(current_app.config.get('DB_FILE', ''))
    instance_file = os.path.join(db_dir, 'instance.json')
    if os.path.exists(instance_file):
        with open(instance_file) as f:
            config = json.load(f)
    else:
        config = {}
    if 'server_url' in data:
        config['server_url'] = data['server_url']
    if 'display_name' in data:
        config['display_name'] = data['display_name']
    if 'sync_secret' in data:
        config['sync_secret'] = data['sync_secret']
    with open(instance_file, 'w') as f:
        json.dump(config, f, indent=2)
    return jsonify({"status": "ok"})

@auth_bp.route('/api/sync/trigger', methods=['POST'])
@login_required
def trigger_sync():
    from core.sync import SyncManager
    try:
        db_file = current_app.config.get('DB_FILE', '')
        instance_id = current_app.config.get('INSTANCE_ID', '')
        server_url = current_app.config.get('SERVER_URL', '')
        sync_secret = ''
        if db_file:
            instance_file = os.path.join(os.path.dirname(db_file), 'instance.json')
            if os.path.exists(instance_file):
                with open(instance_file) as f:
                    sync_secret = json.load(f).get('sync_secret', '')
        if server_url:
            sm = SyncManager(db_file, instance_id, server_url, current_app.config.get('DISPLAY_NAME', ''), sync_secret)
            sm._push()
            sm._pull()
            return jsonify({"status": "ok"})
        return jsonify({"status": "error", "message": "No server URL configured"}), 400
    except Exception as e:
        return jsonify({"status": "error", "message": str(e)}), 500

def init_login_manager(app):
    login_manager.init_app(app)