from flask import Flask
from flask_sqlalchemy import SQLAlchemy
from flask_login import LoginManager
from flask_mail import Mail
from datetime import datetime
import os

db = SQLAlchemy()
login_manager = LoginManager()
mail = Mail()

def create_app():
    app = Flask(__name__)
    
    app.config['SECRET_KEY'] = os.environ.get('SECRET_KEY', 'tu-clave-secreta-cambia-esto')
    app.config['SQLALCHEMY_DATABASE_URI'] = 'sqlite:///fleet.db'
    app.config['SQLALCHEMY_TRACK_MODIFICATIONS'] = False

    app.config['MAIL_SERVER']   = os.environ.get('MAIL_SERVER', 'smtp.gmail.com')
    app.config['MAIL_PORT']     = int(os.environ.get('MAIL_PORT', 587))
    app.config['MAIL_USE_TLS']  = True
    app.config['MAIL_USERNAME'] = os.environ.get('MAIL_USERNAME', '')
    app.config['MAIL_PASSWORD'] = os.environ.get('MAIL_PASSWORD', '')
    app.config['MAIL_DEFAULT_SENDER'] = os.environ.get('MAIL_DEFAULT_SENDER', os.environ.get('MAIL_USERNAME', ''))

    db.init_app(app)
    login_manager.init_app(app)
    mail.init_app(app)
    login_manager.login_view = 'auth.login'
    
    # Registrar rutas
    from app.routes import auth, admin, owner, api
    app.register_blueprint(auth.bp)
    app.register_blueprint(admin.bp)
    app.register_blueprint(owner.bp)
    app.register_blueprint(api.bp)

    from flask import redirect, url_for

    @app.route('/')
    def index():
        return redirect(url_for('auth.login'))
    
    # Crear tablas y migrar columnas nuevas
    with app.app_context():
        db.create_all()
        _run_migrations(db)

    return app

def _run_migrations(db):
    """Agrega columnas nuevas a tablas existentes (SQLite safe)."""
    from sqlalchemy import text, inspect
    inspector = inspect(db.engine)
    existing_tables = inspector.get_table_names()
    with db.engine.connect() as conn:
        # work_orders: priority, notified_at
        if 'work_orders' in existing_tables:
            cols = [c['name'] for c in inspector.get_columns('work_orders')]
            if 'priority' not in cols:
                conn.execute(text("ALTER TABLE work_orders ADD COLUMN priority VARCHAR(20) DEFAULT 'normal'"))
                conn.commit()
            if 'notified_at' not in cols:
                conn.execute(text("ALTER TABLE work_orders ADD COLUMN notified_at DATETIME"))
                conn.commit()
            if 'approved_at' not in cols:
                conn.execute(text("ALTER TABLE work_orders ADD COLUMN approved_at DATETIME"))
                conn.commit()
            if 'approved_by_name' not in cols:
                conn.execute(text("ALTER TABLE work_orders ADD COLUMN approved_by_name VARCHAR(100)"))
                conn.commit()
            if 'rejected_at' not in cols:
                conn.execute(text("ALTER TABLE work_orders ADD COLUMN rejected_at DATETIME"))
                conn.commit()
            if 'rejection_reason' not in cols:
                conn.execute(text("ALTER TABLE work_orders ADD COLUMN rejection_reason VARCHAR(300)"))
                conn.commit()
            if 'invoice_number' not in cols:
                conn.execute(text("ALTER TABLE work_orders ADD COLUMN invoice_number VARCHAR(60)"))
                conn.commit()
        # charters: insurance + captain fields
        if 'charters' in existing_tables:
            cols = [c['name'] for c in inspector.get_columns('charters')]
            for col, ddl in [
                ('insurance_rider_number', "ALTER TABLE charters ADD COLUMN insurance_rider_number VARCHAR(60)"),
                ('insurer_name',           "ALTER TABLE charters ADD COLUMN insurer_name VARCHAR(100)"),
                ('coverage_amount',        "ALTER TABLE charters ADD COLUMN coverage_amount FLOAT"),
                ('damage_waiver',          "ALTER TABLE charters ADD COLUMN damage_waiver FLOAT DEFAULT 0"),
                ('captain_id',             "ALTER TABLE charters ADD COLUMN captain_id INTEGER REFERENCES captains(id)"),
            ]:
                if col not in cols:
                    conn.execute(text(ddl))
                    conn.commit()

        # captains: license_type
        if 'captains' in existing_tables:
            cols = [c['name'] for c in inspector.get_columns('captains')]
            if 'license_type' not in cols:
                conn.execute(text("ALTER TABLE captains ADD COLUMN license_type VARCHAR(20) DEFAULT 'private'"))
                conn.commit()

        # accounting_entries, fuel_entries, documents → ya los crea db.create_all()

        # vessels: management_company_id, max_passengers
        if 'vessels' in existing_tables:
            cols = [c['name'] for c in inspector.get_columns('vessels')]
            if 'management_company_id' not in cols:
                conn.execute(text("ALTER TABLE vessels ADD COLUMN management_company_id INTEGER REFERENCES companies(id)"))
                conn.commit()
            if 'max_passengers' not in cols:
                conn.execute(text("ALTER TABLE vessels ADD COLUMN max_passengers INTEGER DEFAULT 12"))
                conn.commit()

        # users: is_super_admin
        if 'users' in existing_tables:
            cols = [c['name'] for c in inspector.get_columns('users')]
            if 'is_super_admin' not in cols:
                conn.execute(text("ALTER TABLE users ADD COLUMN is_super_admin BOOLEAN DEFAULT 0"))
                conn.commit()

    # Backfill management_company_id for existing vessels
    with db.engine.connect() as conn:
        from sqlalchemy import text
        mgmt = conn.execute(text("SELECT id FROM companies WHERE type='management' LIMIT 1")).fetchone()
        if mgmt:
            conn.execute(text(f"UPDATE vessels SET management_company_id = {mgmt[0]} WHERE management_company_id IS NULL"))
            conn.commit()

    # Mark first admin as super_admin if none exists
    with db.engine.connect() as conn:
        from sqlalchemy import text
        sup = conn.execute(text("SELECT id FROM users WHERE is_super_admin=1 LIMIT 1")).fetchone()
        if not sup:
            first_admin = conn.execute(text("SELECT id FROM users WHERE role='admin' LIMIT 1")).fetchone()
            if first_admin:
                conn.execute(text(f"UPDATE users SET is_super_admin=1 WHERE id={first_admin[0]}"))
                conn.commit()

@login_manager.user_loader
def load_user(user_id):
    from app.models import User
    return User.query.get(int(user_id))