import gradio as gr

def calculate_gpa(grades):
    """
    Calculate GPA based on a comma-separated list of grades.
    Example input: "A, B+, C"
    """
    # Simple GPA scale
    gpa_scale = {
        "A+": 4.0, "A": 4.0, "A-": 3.7,
        "B+": 3.3, "B": 3.0, "B-": 2.7,
        "C+": 2.3, "C": 2.0, "C-": 1.7,
        "D+": 1.3, "D": 1.0, "F": 0.0
    }
    
    # Split grades and calculate
    grades_list = [g.strip().upper() for g in grades.split(",") if g.strip()]
    if not grades_list:
        return "Please enter valid grades like: A, B+, C"

    total = 0
    count = 0
    invalid_grades = []

    for grade in grades_list:
        if grade in gpa_scale:
            total += gpa_scale[grade]
            count += 1
        else:
            invalid_grades.append(grade)

    if count == 0:
        return f"Invalid grades: {', '.join(invalid_grades)}"

    gpa = total / count
    result = f"Your GPA: {gpa:.2f}"
    if invalid_grades:
        result += f" (Ignored invalid grades: {', '.join(invalid_grades)})"
    return result


# Create Gradio Interface
with gr.Blocks() as demo:
    gr.Markdown("# 🎓 Student GPA Calculator")
    gr.Markdown("Enter your grades (comma-separated) to calculate your GPA.")
    
    input_grades = gr.Textbox(
        label="Enter Grades (e.g., A, B+, C)",
        placeholder="A, B+, C"
    )
    output_gpa = gr.Textbox(label="Result")
    calc_button = gr.Button("Calculate GPA")

    calc_button.click(calculate_gpa, inputs=input_grades, outputs=output_gpa)

# Launch app
if __name__ == "__main__":
    demo.launch()