from flask import g, request, current_app
from flask_babel import get_locale
from flask_login import current_user
from app.models import Settings
from app.utils.timezone import get_timezone_offset_for_timezone


def register_context_processors(app):
    """Register context processors for the application"""

    # Register permission helpers for templates
    from app.utils.permissions import init_permission_helpers

    init_permission_helpers(app)

    @app.context_processor
    def inject_settings():
        """Inject settings into all templates"""
        try:
            from app import db

            # Check if we have an active database session
            if db.session.is_active:
                settings = Settings.get_settings()
                return {"settings": settings, "currency": settings.currency, "timezone": settings.timezone}
        except Exception as e:
            # Log the error but continue with defaults
            print(f"Warning: Could not inject settings: {e}")
            # Rollback the failed transaction
            try:
                from app import db

                db.session.rollback()
            except Exception:
                pass
            pass

        # Return defaults if settings not available
        return {"settings": None, "currency": "EUR", "timezone": "Europe/Rome"}

    @app.context_processor
    def inject_globals():
        """Inject global variables into all templates"""
        try:
            from app import db

            # Check if we have an active database session
            if db.session.is_active:
                settings = Settings.get_settings()
                timezone_name = settings.timezone if settings else "Europe/Rome"
            else:
                timezone_name = "Europe/Rome"
        except Exception as e:
            # Log the error but continue with defaults
            print(f"Warning: Could not inject globals: {e}")
            # Rollback the failed transaction
            try:
                from app import db

                db.session.rollback()
            except Exception:
                pass
            timezone_name = "Europe/Rome"

        # Resolve user-specific timezone, falling back to application timezone
        user_timezone = timezone_name
        try:
            if (
                current_user
                and getattr(current_user, "is_authenticated", False)
                and getattr(current_user, "timezone", None)
            ):
                user_timezone = current_user.timezone
        except Exception:
            pass

        # Determine app version from setup.py (single source of truth)
        try:
            from app.config.analytics_defaults import get_version_from_setup
            import os

            # Get version from setup.py
            version_value = get_version_from_setup()
            
            # If version is "unknown", fall back to environment variable for dev mode
            if version_value == "unknown":
                env_version = os.getenv("APP_VERSION")
                if env_version:
                    version_value = env_version
                else:
                    # Last resort: use "dev-0" for development
                    version_value = "dev-0"
            
            # Strip any leading 'v' prefix to avoid double 'v' in template (e.g., vv3.5.0)
            if version_value and version_value.startswith("v"):
                version_value = version_value[1:]
        except Exception:
            # Fallback if anything goes wrong
            version_value = "dev-0"

        # Current locale code (e.g., 'en', 'de')
        try:
            current_locale = str(get_locale())
        except Exception:
            current_locale = "en"
        # Normalize to short code for comparisons (e.g., 'en' from 'en_US')
        short_locale = current_locale.split("_", 1)[0] if current_locale else "en"

        # Reverse-map normalized locale codes back to config keys for label lookup
        # 'nb' (used by Flask-Babel) should map back to 'no' (used in LANGUAGES config)
        display_locale = short_locale
        if short_locale == "nb":
            display_locale = "no"

        available_languages = current_app.config.get("LANGUAGES", {}) or {}
        current_language_label = available_languages.get(display_locale, short_locale.upper())

        # Check if current language is RTL
        rtl_languages = current_app.config.get("RTL_LANGUAGES", set())
        is_rtl = short_locale in rtl_languages

        return {
            "app_name": "Time Tracker",
            "app_version": version_value,
            "timezone": timezone_name,
            "timezone_offset": get_timezone_offset_for_timezone(timezone_name),
            "user_timezone": user_timezone,
            "current_locale": current_locale,
            "current_language_code": display_locale,  # Use display locale (e.g., 'no' not 'nb')
            "current_language_label": current_language_label,
            "is_rtl": is_rtl,
            "available_languages": available_languages,
            "config": current_app.config,
        }

    @app.before_request
    def before_request():
        """Set up request-specific data"""
        g.request_start_time = request.start_time if hasattr(request, "start_time") else None