# OCR Translate v0.2
# 创建人：曾逸夫 (Founder: Zeng Yifu)
# Creation time：2022-07-19

import os

#os.system("apt-get install xclip")

import gradio as gr
import nltk
import pyclip
import pytesseract
import nltk
from nltk.tokenize import sent_tokenize
from transformers import MarianMTModel, MarianTokenizer
from transformers import T5Tokenizer, T5ForConditionalGeneration

nltk.download('punkt')
nltk.download('punkt_tab')

OCR_TR_DESCRIPTION = '''# OCR Translate v0.2
<div id="content_align">OCR translation system based on Tesseract</div>'''

# Image Path
img_dir = "./data"

# Get tesseract language list
choices = os.popen('tesseract --list-langs').read().split('\n')[1:-1]


# Translation model selection
def model_choice(src, trg):
    # https://huggingface.co/Helsinki-NLP/opus-mt-tc-big-pt-en
    # https://huggingface.co/Helsinki-NLP/opus-mt-tc-big-en-pt
    # https://huggingface.co/unicamp-dl/translation-pt-en-t5
    # https://huggingface.co/unicamp-dl/translation-en-pt-t5
    model_name = f"unicamp-dl/translation-{src}-{trg}-t5"  # Model Name

    #tokenizer = MarianTokenizer.from_pretrained(model_name)  # Tokenizer
    #model = MarianMTModel.from_pretrained(model_name)  # Model

    tokenizer = T5Tokenizer.from_pretrained(model_name)
    model = T5ForConditionalGeneration.from_pretrained(model_name)

    return tokenizer, model


# Convert tesseract language list to pytesseract language
def ocr_lang(lang_list):
    lang_str = ""
    lang_len = len(lang_list)
    if lang_len == 1:
        return lang_list[0]
    else:
        for i in range(lang_len):
            lang_list.insert(lang_len - i, "+")

        lang_str = "".join(lang_list[:-1])
        return lang_str


# ocr tesseract
def ocr_tesseract(img, languages):
    ocr_str = pytesseract.image_to_string(img, lang=ocr_lang(languages))
    return ocr_str


# Clear
def clear_content():
    return None


# Copy to Clipboard
def cp_text(input_text):
    # sudo apt-get install xclip
    try:
        pyclip.copy(input_text)
    except Exception as e:
        print("sudo apt-get install xclip")
        print(e)


# Clear Clipboard
def cp_clear():
    pyclip.clear()


# Translate
def translate(input_text, inputs_transStyle):
    # Reference：https://huggingface.co/docs/transformers/model_doc/marian
    if input_text is None or input_text == "":
        return "System prompt: There is no content to translate!"

    # Selecting a translation model
    trans_src, trans_trg = inputs_transStyle.split("-")[0], inputs_transStyle.split("-")[1]
    tokenizer, model = model_choice(trans_src, trans_trg)

    translate_text = ""
    input_text_list = input_text.split("\n\n")

    translate_text_list_tmp = []
    for i in range(len(input_text_list)):
        if input_text_list[i] != "":
            translate_text_list_tmp.append(input_text_list[i])

    for i in range(len(translate_text_list_tmp)):
        translated_sub = model.generate(
            **tokenizer(sent_tokenize(translate_text_list_tmp[i]), return_tensors="pt", truncation=True, padding=True))
        tgt_text_sub = [tokenizer.decode(t, skip_special_tokens=True) for t in translated_sub]
        translate_text_sub = "".join(tgt_text_sub)
        translate_text = translate_text + "\n\n" + translate_text_sub

    return translate_text[2:]


def main():

    with gr.Blocks(css='style.css') as ocr_tr:
        gr.Markdown(OCR_TR_DESCRIPTION)

        # -------------- OCR Text Extraction --------------
        with gr.Blocks():

            with gr.Row():
                gr.Markdown("### Step 01: Text Extraction")

            with gr.Row():
                with gr.Column():
                    with gr.Row():
                        inputs_img = gr.Image(image_mode="RGB", sources="upload", type="pil", label="image")
                    with gr.Row():
                        inputs_lang = gr.CheckboxGroup(choices=["por", "eng"],
                                                       type="value",
                                                       value=['eng'],
                                                       label='language')

                    with gr.Row():
                        clear_img_btn = gr.Button('Clear')
                        ocr_btn = gr.Button(value='OCR Extraction', variant="primary")

                with gr.Column():
                    with gr.Row():
                        outputs_text = gr.Textbox(label="Extract content", lines=20)
                    with gr.Row():
                        inputs_transStyle = gr.Radio(choices=["pt-en", "en-pt"],
                                                     type="value",
                                                     value="pt-en",
                                                     label='translation mode')
                    with gr.Row():
                        clear_text_btn = gr.Button('Clear')
                        translate_btn = gr.Button(value='Translate', variant="primary")

            with gr.Row():
                example_list = [["./data/test.png", ["eng"]], ["./data/test02.png", ["eng"]],
                                ["./data/test03.png", ["por"]]]
                gr.Examples(example_list, [inputs_img, inputs_lang], outputs_text, ocr_tesseract, cache_examples=False)

        # -------------- Translate --------------
        with gr.Blocks():

            with gr.Row():
                gr.Markdown("### Step 02: Translation")

            with gr.Row():
                outputs_tr_text = gr.Textbox(label="Translate Content", lines=20)

            with gr.Row():
                cp_clear_btn = gr.Button(value='Clear Clipboard')
                cp_btn = gr.Button(value='Copy to clipboard', variant="primary")

        # ---------------------- OCR Tesseract ----------------------
        ocr_btn.click(fn=ocr_tesseract, inputs=[inputs_img, inputs_lang], outputs=[
            outputs_text,])
        clear_img_btn.click(fn=clear_content, inputs=[], outputs=[inputs_img])

        # ---------------------- Translate ----------------------
        translate_btn.click(fn=translate, inputs=[outputs_text, inputs_transStyle], outputs=[outputs_tr_text])
        clear_text_btn.click(fn=clear_content, inputs=[], outputs=[outputs_text])

        # ---------------------- Copy to Clipboard ----------------------
        cp_btn.click(fn=cp_text, inputs=[outputs_tr_text], outputs=[])
        cp_clear_btn.click(fn=cp_clear, inputs=[], outputs=[])

    ocr_tr.launch(inbrowser=True)


if __name__ == '__main__':
    main()