import gradio as gr
from datasets import load_dataset
from datetime import datetime
import io
from PIL import Image, ImageDraw, ImageFont

# Constants
SCORES_DATASET = "agents-course/unit4-students-scores"
CERTIFICATES_DATASET = "agents-course/course-certificates-of-excellence"
THRESHOLD_SCORE = 45

# Function to check user score
def check_user_score(username):
    score_data = load_dataset(SCORES_DATASET, split="train", download_mode="force_redownload")
    matches = [row for row in score_data if row["username"] == username]
    return matches[0] if matches else None

# Function to check if certificate entry exists
def has_certificate_entry(username):
    cert_data = load_dataset(CERTIFICATES_DATASET, split="train", download_mode="force_redownload")
    return any(row["username"] == username for row in cert_data)

# Function to add certificate entry
def add_certificate_entry(username, name):
    new_entry = {
        "username": username,
        "name": name,
        "date": datetime.now().strftime("%Y-%m-%d"),
    }
    ds = load_dataset(CERTIFICATES_DATASET, split="train")
    ds = ds.add_item(new_entry)
    ds.push_to_hub(CERTIFICATES_DATASET)

# Function to generate certificate PDF
def generate_certificate(name, score):
    """Generate certificate image and PDF."""
    certificate_path = os.path.join(
        os.path.dirname(__file__), "templates", "certificate.png"
    )
    im = Image.open(certificate_path)
    d = ImageDraw.Draw(im)

    name_font = ImageFont.truetype("Quattrocento-Regular.ttf", 100)
    date_font = ImageFont.truetype("Quattrocento-Regular.ttf", 48)

    name = name.title()
    d.text((1000, 740), name, fill="black", anchor="mm", font=name_font)

    d.text((1480, 1170), str(date.today()), fill="black", anchor="mm", font=date_font)

    pdf = im.convert("RGB")
    pdf.save("certificate.pdf")

    return im, "certificate.pdf"

# Main function to handle certificate generation
def handle_certificate(name, profile: gr.OAuthProfile):
    if profile is None:
        return "You must be logged in with your Hugging Face account.", None

    username = profile.username
    user_score = check_user_score(username)

    if not user_score:
        return "You need to complete Unit 4 first.", None

    score = user_score["score"]

    if score < THRESHOLD_SCORE:
        return f"Your score is {score}. You need at least {THRESHOLD_SCORE} to pass.", None

    if not has_certificate_entry(username):
        add_certificate_entry(username, name)

    certificate = generate_certificate(name, score)
    return "Congratulations! Here's your certificate:", certificate

# Gradio interface
with gr.Blocks() as demo:
    gr.Markdown("# 🎓 Unit 4 Certificate Generator")
    gr.LoginButton()
    with gr.Row():
        name_input = gr.Text(label="Enter your name")
    generate_btn = gr.Button("Get my certificate")
    output_text = gr.Textbox(label="Result")
    cert_image = gr.Image(label="Your Certificate")
    cert_file = gr.File(label="Download Certificate (PDF)", file_types=[".pdf"])

    generate_btn.click(
        fn=handle_certificate,
        inputs=[name_input],
        outputs=[output_text, cert_image, cert_file]
    )

demo.launch()