# app/templates_config.py
"""
Shared Jinja2 templates configuration.

All route modules should import `templates` from here to ensure
consistent globals (like translation function) are available.

Template Loading Strategy:
- Core templates from app/templates/ (highest priority)
- Module templates from app/modules/<module>/templates/ (namespaced)

Module templates should use namespace prefix to avoid collisions:
    app/modules/cms/templates/cms/admin/pages.html
    -> Rendered as: templates.TemplateResponse("cms/admin/pages.html", ...)
"""

import logging
from datetime import datetime
from pathlib import Path

from fastapi.templating import Jinja2Templates
from jinja2 import ChoiceLoader, FileSystemLoader

from app.utils.i18n import (
    DEFAULT_LANGUAGE,
    LANGUAGE_FLAGS,
    LANGUAGE_NAMES,
    SUPPORTED_LANGUAGES,
    create_translation_context,
)

logger = logging.getLogger(__name__)

# Core templates directory
TEMPLATES_DIR = Path(__file__).parent / "templates"
MODULES_DIR = Path(__file__).parent / "modules"


def create_template_loaders() -> ChoiceLoader:
    """
    Create a ChoiceLoader that searches multiple template directories.

    Search order:
    1. Core templates (app/templates/) - highest priority
    2. Module templates (app/modules/<module>/templates/) - in alphabetical order

    Returns:
        ChoiceLoader configured with all template directories
    """
    loaders = [FileSystemLoader(str(TEMPLATES_DIR))]  # Core templates first

    # Add module template directories
    if MODULES_DIR.exists():
        for module_dir in sorted(MODULES_DIR.iterdir()):
            if module_dir.is_dir():
                templates_path = module_dir / "templates"
                if templates_path.exists() and templates_path.is_dir():
                    loaders.append(FileSystemLoader(str(templates_path)))
                    logger.debug(f"[Templates] Added module templates: {module_dir.name}")

    return ChoiceLoader(loaders)


def get_module_template_dirs() -> list[Path]:
    """
    Get list of all module template directories.

    Useful for debugging and introspection.

    Returns:
        List of Path objects for module template directories
    """
    dirs = []
    if MODULES_DIR.exists():
        for module_dir in sorted(MODULES_DIR.iterdir()):
            if module_dir.is_dir():
                templates_path = module_dir / "templates"
                if templates_path.exists() and templates_path.is_dir():
                    dirs.append(templates_path)
    return dirs


# Create shared templates instance with multi-directory loader
templates = Jinja2Templates(directory=str(TEMPLATES_DIR))
templates.env.loader = create_template_loaders()

# Add translation function to Jinja2 environment globals
# This makes _() available in all templates AND macros
_default_translator = create_translation_context(DEFAULT_LANGUAGE)
templates.env.globals["_"] = _default_translator
templates.env.globals["t"] = _default_translator  # Alias
templates.env.globals["SUPPORTED_LANGUAGES"] = SUPPORTED_LANGUAGES
templates.env.globals["DEFAULT_LANGUAGE"] = DEFAULT_LANGUAGE
templates.env.globals["LANGUAGE_NAMES"] = LANGUAGE_NAMES
templates.env.globals["LANGUAGE_FLAGS"] = LANGUAGE_FLAGS
templates.env.globals["current_year"] = datetime.now().year