# app/__init__.py
import os
from dotenv import load_dotenv
from flask import Flask, render_template
from flask_sqlalchemy import SQLAlchemy
from flask_login import LoginManager, current_user
from flask_migrate import Migrate
from flask_limiter import Limiter
from flask_limiter.util import get_remote_address
from flask_mail import Mail

from .config import Config

load_dotenv()

# ----------------------------------------------------------------------
# Extensions (created once, attached later)
# ----------------------------------------------------------------------
db = SQLAlchemy()
login_manager = LoginManager()
migrate = Migrate()
limiter = Limiter(key_func=get_remote_address)
mail = Mail()


def create_app():
    app = Flask(__name__)
    app.config.from_object(Config)

    # ------------------------------------------------------------------
    # Initialise extensions
    # ------------------------------------------------------------------
    db.init_app(app)
    login_manager.init_app(app)
    migrate.init_app(app, db)
    limiter.init_app(app)
    mail.init_app(app)

    login_manager.login_view = "auth.login"
    login_manager.login_message_category = "info"

    # ------------------------------------------------------------------
    # Create upload directories (safe – does nothing if they already exist)
    # ------------------------------------------------------------------
    os.makedirs(os.path.join(app.root_path, 'static', 'uploads', 'docx'), exist_ok=True)
    os.makedirs(app.config['UPLOAD_FOLDER'], exist_ok=True)

    # ------------------------------------------------------------------
    # Register blueprints
    # ------------------------------------------------------------------
    from .routes.auth import auth_bp
    from .routes.main import main_bp
    from .routes.users import users_bp
    from .routes.permission import permissions_bp
    from .routes.role import roles_bp
    from .routes.department import departments_bp
    from .routes.contract import contracts_bp
    from .routes.mydepartments import mydepartments_bp
    from .routes.reports import reports_bp
    from .routes.interns import interns_bp
    from .routes.employees import employees_bp
    # <<< NEW BLUEPRINT >>>
    from .routes.docx_upload import docx_upload_bp
    from .routes.employees_upload import employees_upload_bp
    from .routes.interns_upload import interns_upload_bp

    app.register_blueprint(auth_bp, url_prefix="/auth")
    app.register_blueprint(main_bp)
    app.register_blueprint(users_bp, url_prefix="/users")
    app.register_blueprint(permissions_bp, url_prefix="/permissions")
    app.register_blueprint(roles_bp, url_prefix="/roles")
    app.register_blueprint(departments_bp, url_prefix="/departments")
    app.register_blueprint(contracts_bp, url_prefix="/contracts")
    app.register_blueprint(mydepartments_bp, url_prefix="/mydepartments")
    app.register_blueprint(reports_bp, url_prefix="/reports")
    app.register_blueprint(interns_bp, url_prefix="/interns")
    app.register_blueprint(employees_bp, url_prefix="/employees")
    # <<< NEW BLUEPRINT >>>
    app.register_blueprint(docx_upload_bp, url_prefix="/contracts")
    app.register_blueprint(employees_upload_bp, url_prefix="/employees")
    app.register_blueprint(interns_upload_bp, url_prefix="/interns")

    # ------------------------------------------------------------------
    # Import models (only after db is attached)
    # ------------------------------------------------------------------
    from .models.user import User
    from .models.permission import Permission
    from .models.role import Role
    from .models.department import Department
    from .models.contract import Contract
    from .models.notification import Notification
    from .models.interns import Intern
    from .models.employees import Employee
    # <<< NEW MODEL >>>
    from .models.uploaded_docx import UploadedDocx
    from .models.uploaded_employee import UploadedEmployee
    from .models.uploaded_intern import UploadedIntern

    # ------------------------------------------------------------------
    # Flask-Login user loader
    # ------------------------------------------------------------------
    @login_manager.user_loader
    def load_user(user_id):
        return User.query.get(int(user_id))

    # ------------------------------------------------------------------
    # Context processor – notifications for admins
    # ------------------------------------------------------------------
    @app.context_processor
    def inject_notifications():
        if current_user.is_authenticated and current_user.has_role('Admin'):
            unread_count = Notification.query.filter_by(
                recipient_id=current_user.id, is_read=False
            ).count()
            notifications = (
                Notification.query.filter_by(recipient_id=current_user.id)
                .order_by(Notification.created_at.desc())
                .limit(7)
                .all()
            )
            notifications_dict = [n.to_dict() for n in notifications]
            return {"unread_count": unread_count, "notifications": notifications_dict}
        return {"unread_count": 0, "notifications": []}

    # ------------------------------------------------------------------
    # Error handlers
    # ------------------------------------------------------------------
    @app.errorhandler(404)
    def not_found_error(error):
        return render_template('errors/404.html'), 404

    @app.errorhandler(500)
    def internal_error(error):
        db.sessionrollback()          # rollback on error
        return render_template('errors/500.html'), 500
    @app.errorhandler(502)
    def bad_gateway(error):
        return render_template('errors/502.html'), 502


    return app