main.py

"""
main.py

This is the application factory for the Nyota ✨ project.
"""

import os
import json
from datetime import timedelta
from flask import Flask, g, session, request
from flask_babel import Babel
import mistune
from flask_compress import Compress

from config import Config
from models.nyota import db, migrate
from routes import main_bp, admin_bp

babel = Babel()

# --- Jinja2 Custom Filters ---

def format_currency(value, symbol='$'):
    if value is None:
        return f"{symbol} 0.00"
    return f"{symbol} {float(value):,.2f}"

from utils.translator import translate

# --- Language Selection for Babel ---

def get_locale():
    if 'language' in session:
        return session['language']
    
    # Check headers for country code (Cloudflare, App Engine, or Generic)
    country = request.headers.get('CF-IPCountry') or \
              request.headers.get('X-AppEngine-Country') or \
              request.headers.get('X-Country-Code')
    
    # If a country is detected and it is NOT Tanzania, default to English
    if country and country.upper() != 'TZ':
        return 'en'
        
    # Default to Swahili for Tanzania and all unknown locations
    return 'sw'


# --- Application Factory Function ---

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

    # Trust the reverse proxy's X-Forwarded-Proto header so request.url_root
    # uses https:// instead of http:// when behind nginx/Cloudflare.
    from werkzeug.middleware.proxy_fix import ProxyFix
    app.wsgi_app = ProxyFix(app.wsgi_app, x_proto=1, x_host=1)

    # --- Initialize Flask Extensions ---
    db.init_app(app)
    migrate.init_app(app, db)
    babel.init_app(app, locale_selector=get_locale)
    Compress(app)
    app.config['SEND_FILE_MAX_AGE_DEFAULT'] = 31536000  # 1 year cache for static files

    # --- Register Jinja2 Filters ---
    app.jinja_env.filters['format_currency'] = format_currency

    def nl2br(value):
        from markupsafe import Markup, escape
        if not value:
            return ""
        return Markup(str(escape(value)).replace('\n', '<br>\n'))
    
    app.jinja_env.filters['nl2br'] = nl2br
    
    # This lambda function takes text, processes it with mistune, and returns HTML.
    app.jinja_env.filters['markdown'] = lambda text: mistune.html(text)

    # --- Register Blueprints ---
    app.register_blueprint(main_bp)
    app.register_blueprint(admin_bp)

    # --- Request Hooks ---
    @app.before_request
    def before_request_tasks():
        session.permanent = True
        app.permanent_session_lifetime = timedelta(days=30)
        g.language = get_locale()

    # --- Context Processors ---
    @app.context_processor
    def inject_global_vars():
        return dict(
            store_name="Nyota ✨",
            currency_symbol=get_currency_symbol(),
            translate=translate
        )

    def get_currency_symbol():
        from models.nyota import Creator
        creator = Creator.query.first()
        if creator:
            return creator.get_setting('payment_uza_currency', 'TZS')
        return 'TZS'

    # --- Cache Headers for Static Assets ---
    @app.after_request
    def add_cache_headers(response):
        if request.path.startswith('/static/'):
            response.cache_control.max_age = 31536000
            response.cache_control.public = True
        return response

    # Start background worker (scheduled campaigns + subscription reminders).
    # Suppressed during flask db migrate / flask db upgrade via env var.
    import os
    if not os.environ.get('FLASK_SKIP_BACKGROUND_WORKER'):
        from services.background_tasks import start_background_worker
        start_background_worker(app)

    return app