# app.py
# pip install gradio qrcode[pil]

import gradio as gr
from PIL import Image
import qrcode
from qrcode.constants import ERROR_CORRECT_L, ERROR_CORRECT_M, ERROR_CORRECT_Q, ERROR_CORRECT_H

EC_MAP = {
    "L (7%)": ERROR_CORRECT_L,
    "M (15%)": ERROR_CORRECT_M,
    "Q (25%)": ERROR_CORRECT_Q,
    "H (30%)": ERROR_CORRECT_H,
}

def make_qr(
    text: str,
    error_level: str,
    box_size: int,
    border: int,
    fill_color: str,
    back_color: str,
):
    if not text or not text.strip():
        return Image.new("RGB", (256, 256), color="white")
    qr = qrcode.QRCode(
        version=None,                    # let library choose optimal size
        error_correction=EC_MAP[error_level],
        box_size=box_size,
        border=border,
    )
    qr.add_data(text.strip())
    qr.make(fit=True)
    img = qr.make_image(fill_color=fill_color, back_color=back_color)
    return img.convert("RGB")

with gr.Blocks(title="Text → QR Code") as demo:
    gr.Markdown("# Text → QR Code")
    with gr.Row():
        with gr.Column():
            text = gr.Textbox(label="Text or URL", placeholder="Type or paste your text here…", lines=4)
            error_level = gr.Dropdown(
                choices=list(EC_MAP.keys()),
                value="M (15%)",
                label="Error correction",
            )
            box_size = gr.Slider(4, 20, value=10, step=1, label="Box size (pixel per module)")
            border = gr.Slider(1, 10, value=4, step=1, label="Border (modules)")
            fill_color = gr.ColorPicker(value="#000000", label="QR color")
            back_color = gr.ColorPicker(value="#FFFFFF", label="Background color")
            btn = gr.Button("Generate", variant="primary")
        with gr.Column():
            out = gr.Image(type="pil", label="QR Code", height=400)

    btn.click(
        fn=make_qr,
        inputs=[text, error_level, box_size, border, fill_color, back_color],
        outputs=out,
    )

if __name__ == "__main__":
    demo.launch()