"""Explainable recommendation rules for Project 03."""


def recommend_lesson(
    experience: str,
    goal: str,
    knows_python: bool,
    completed_topics: list[str],
) -> tuple[str, str]:
    """Recommend the next lesson and explain the decision."""

    experience = experience.strip().lower()
    goal = goal.strip().lower()
    completed = {topic.strip().lower() for topic in completed_topics}

    if experience == "beginner" and "ai foundations" not in completed:
        return (
            "Ai Foundations",
            "Start with the basic concepts before selecting a specialization.",
        )

    if not knows_python:
        return (
            "Python Foundations",
            "Basic Python knowledge is recommended before practical Ai projects.",
        )

    if goal == "machine learning":
        if "data preparation" not in completed:
            return (
                "Data Preparation",
                "Machine Learning requires clean and well-structured data.",
            )

        return (
            "Supervised Learning Basics",
            "You are ready to begin classification and regression.",
        )

    if goal == "generative ai":
        return (
            "Prompt Engineering",
            "This introduces structured interaction with Generative Ai models.",
        )

    if goal == "computer vision":
        return (
            "Image Classification Basics",
            "Image classification is a suitable starting point for Computer Vision.",
        )

    return (
        "Ai Applications Overview",
        "Explore the main Ai application areas before selecting a pathway.",
    )