import jinja2
from jinja2.sandbox import SandboxedEnvironment
from typing import Any, Dict


class TemplateService:
    """
    Service for rendering Jinja2 templates with variable resolution.
    
    Uses a sandboxed environment with StrictUndefined to prevent security issues
    and raise errors on undefined variables.
    """

    def __init__(self):
        self.env = SandboxedEnvironment(
            undefined=jinja2.StrictUndefined,
            autoescape=False,  # We're not rendering HTML
            trim_blocks=True,
            lstrip_blocks=True,
        )

    def render(self, template: str, context: Dict[str, Any]) -> str:
        """
        Render a Jinja2 template with the provided context.

        Args:
            template: Jinja2 template string.
            context: Dictionary of variables to make available in the template.

        Returns:
            Rendered string.

        Raises:
            jinja2.TemplateError: If template syntax is invalid or rendering fails.
        """
        try:
            jinja_template = self.env.from_string(template)
            return jinja_template.render(**context)
        except jinja2.TemplateError as e:
            # Re-raise with additional context
            raise jinja2.TemplateError(f"Failed to render template: {e}") from e