from typing import List
import pytesseract
from PIL import Image
import gradio as gr

def tesseract_ocr(filepath: str, languages: List[str] = None):
    if not languages:
        languages = ['eng']
    image = Image.open(filepath)
    lang_param = '+'.join(languages)
    return pytesseract.image_to_string(image=image, lang=lang_param)

title = "Tesseract OCR"
description = "Gradio demo for Tesseract. Tesseract is an open source text recognition (OCR) Engine."
article = "<p style='text-align: center'><a href='https://tesseract-ocr.github.io/' target='_blank'>Tesseract documentation</a> | <a href='https://github.com/tesseract-ocr/tesseract' target='_blank'>Github Repo</a></p>"

examples = [
    ["examples/weird_unicode_math_symbols.png", []],
    ["examples/eurotext.png", ["eng"]],
    ["examples/tesseract_sample.png", ["jpn", "eng"]],
    ["examples/chi.jpg", ["chi_sim", "chi_tra"]],
]

with gr.Blocks(title=title) as demo:
    gr.Markdown(f'<h1 style="text-align: center; margin-bottom: 1rem;">{title}</h1>')
    gr.Markdown(description)

    with gr.Row():
        with gr.Column():
            image = gr.Image(type="filepath", label="Input")
            language_choices = pytesseract.get_languages(config='')  # <- safer
            with gr.Accordion("Languages", open=False):
                languages = gr.CheckboxGroup(language_choices, value=["eng"], label="Language(s)")
            with gr.Row():
                btn_clear = gr.ClearButton([image, languages])
                btn_submit = gr.Button(value="Submit", variant="primary")

        with gr.Column():
            text = gr.Textbox(label="Output")

    btn_submit.click(tesseract_ocr, inputs=[image, languages], outputs=text)
    btn_clear.add(text)

    gr.Examples(
        examples=examples,
        inputs=[image, languages],
        outputs=[text],
        fn=tesseract_ocr
    )

    gr.Markdown(article)

if __name__ == '__main__':
    demo.queue().launch()