pdf2zh/gui.py

import asyncio
import cgi
import os
import shutil
import uuid
from asyncio import CancelledError
from pathlib import Path

import gradio as gr
import requests
import tqdm
from gradio_pdf import PDF
from string import Template

from pdf2zh import __version__
from pdf2zh.high_level import translate
from pdf2zh.doclayout import ModelInstance
from pdf2zh.config import ConfigManager
from pdf2zh.translator import (
    AnythingLLMTranslator,
    AzureOpenAITranslator,
    AzureTranslator,
    BaseTranslator,
    BingTranslator,
    DeepLTranslator,
    DeepLXTranslator,
    DifyTranslator,
    ArgosTranslator,
    GeminiTranslator,
    GoogleTranslator,
    ModelScopeTranslator,
    OllamaTranslator,
    OpenAITranslator,
    SiliconTranslator,
    TencentTranslator,
    XinferenceTranslator,
    ZhipuTranslator,
    GorkTranslator,
    GroqTranslator,
    DeepseekTranslator,
    OpenAIlikedTranslator,
    QwenMtTranslator,
)

# The following variables associate strings with translators
service_map: dict[str, BaseTranslator] = {
    "Google": GoogleTranslator,
    "Bing": BingTranslator,
    "DeepL": DeepLTranslator,
    "DeepLX": DeepLXTranslator,
    "Ollama": OllamaTranslator,
    "Xinference": XinferenceTranslator,
    "AzureOpenAI": AzureOpenAITranslator,
    "OpenAI": OpenAITranslator,
    "Zhipu": ZhipuTranslator,
    "ModelScope": ModelScopeTranslator,
    "Silicon": SiliconTranslator,
    "Gemini": GeminiTranslator,
    "Azure": AzureTranslator,
    "Tencent": TencentTranslator,
    "Dify": DifyTranslator,
    "AnythingLLM": AnythingLLMTranslator,
    "Argos Translate": ArgosTranslator,
    "Grok": GorkTranslator,
    "Groq": GroqTranslator,
    "DeepSeek": DeepseekTranslator,
    "OpenAI-liked": OpenAIlikedTranslator,
    "Ali Qwen-Translation": QwenMtTranslator,
}

# The following variables associate strings with specific languages
lang_map = {
    "Simplified Chinese": "zh",
    "Traditional Chinese": "zh-TW",
    "English": "en",
    "French": "fr",
    "German": "de",
    "Japanese": "ja",
    "Korean": "ko",
    "Russian": "ru",
    "Spanish": "es",
    "Italian": "it",
}

# The following variable associate strings with page ranges
page_map = {
    "All": None,
    "First": [0],
    "First 5 pages": list(range(0, 5)),
    "Others": None,
}

# Check if this is a public demo, which has resource limits
flag_demo = False

# Limit resources
if ConfigManager.get("PDF2ZH_DEMO"):
    flag_demo = True
    service_map = {
        "Google": GoogleTranslator,
    }
    page_map = {
        "First": [0],
        "First 20 pages": list(range(0, 20)),
    }
    client_key = ConfigManager.get("PDF2ZH_CLIENT_KEY")
    server_key = ConfigManager.get("PDF2ZH_SERVER_KEY")


# Public demo control
def verify_recaptcha(response):
    """
    This function verifies the reCAPTCHA response.
    """
    recaptcha_url = "https://www.google.com/recaptcha/api/siteverify"
    print("reCAPTCHA", server_key, response)
    data = {"secret": server_key, "response": response}
    result = requests.post(recaptcha_url, data=data).json()
    print("reCAPTCHA", result.get("success"))
    return result.get("success")


def download_with_limit(url: str, save_path: str, size_limit: int) -> str:
    """
    This function downloads a file from a URL and saves it to a specified path.

    Inputs:
        - url: The URL to download the file from
        - save_path: The path to save the file to
        - size_limit: The maximum size of the file to download

    Returns:
        - The path of the downloaded file
    """
    chunk_size = 1024
    total_size = 0
    with requests.get(url, stream=True, timeout=10) as response:
        response.raise_for_status()
        content = response.headers.get("Content-Disposition")
        try:  # filename from header
            _, params = cgi.parse_header(content)
            filename = params["filename"]
        except Exception:  # filename from url
            filename = os.path.basename(url)
        with open(save_path / filename, "wb") as file:
            for chunk in response.iter_content(chunk_size=chunk_size):
                total_size += len(chunk)
                if size_limit and total_size > size_limit:
                    raise gr.Error("Exceeds file size limit")
                file.write(chunk)
    return save_path / filename


def stop_translate_file(state: dict) -> None:
    """
    This function stops the translation process.

    Inputs:
        - state: The state of the translation process

    Returns:- None
    """
    session_id = state["session_id"]
    if session_id is None:
        return
    if session_id in cancellation_event_map:
        cancellation_event_map[session_id].set()


def translate_file(
    file_type,
    file_input,
    link_input,
    service,
    lang_from,
    lang_to,
    page_range,
    page_input,
    prompt,
    threads,
    skip_subset_fonts,
    recaptcha_response,
    state,
    progress=gr.Progress(),
    *envs,
):
    """
    This function translates a PDF file from one language to another.

    Inputs:
        - file_type: The type of file to translate
        - file_input: The file to translate
        - link_input: The link to the file to translate
        - service: The translation service to use
        - lang_from: The language to translate from
        - lang_to: The language to translate to
        - page_range: The range of pages to translate
        - page_input: The input for the page range
        - prompt: The custom prompt for the llm
        - threads: The number of threads to use
        - recaptcha_response: The reCAPTCHA response
        - state: The state of the translation process
        - progress: The progress bar
        - envs: The environment variables

    Returns:
        - The translated file
        - The translated file
        - The translated file
        - The progress bar
        - The progress bar
        - The progress bar
    """
    session_id = uuid.uuid4()
    state["session_id"] = session_id
    cancellation_event_map[session_id] = asyncio.Event()
    # Translate PDF content using selected service.
    if flag_demo and not verify_recaptcha(recaptcha_response):
        raise gr.Error("reCAPTCHA fail")

    progress(0, desc="Starting translation...")

    output = Path("pdf2zh_files")
    output.mkdir(parents=True, exist_ok=True)

    if file_type == "File":
        if not file_input:
            raise gr.Error("No input")
        file_path = shutil.copy(file_input, output)
    else:
        if not link_input:
            raise gr.Error("No input")
        file_path = download_with_limit(
            link_input,
            output,
            5 * 1024 * 1024 if flag_demo else None,
        )

    filename = os.path.splitext(os.path.basename(file_path))[0]
    file_raw = output / f"{filename}.pdf"
    file_mono = output / f"{filename}-mono.pdf"
    file_dual = output / f"{filename}-dual.pdf"

    translator = service_map[service]
    if page_range != "Others":
        selected_page = page_map[page_range]
    else:
        selected_page = []
        for p in page_input.split(","):
            if "-" in p:
                start, end = p.split("-")
                selected_page.extend(range(int(start) - 1, int(end)))
            else:
                selected_page.append(int(p) - 1)
    lang_from = lang_map[lang_from]
    lang_to = lang_map[lang_to]

    _envs = {}
    for i, env in enumerate(translator.envs.items()):
        _envs[env[0]] = envs[i]

    print(f"Files before translation: {os.listdir(output)}")

    def progress_bar(t: tqdm.tqdm):
        progress(t.n / t.total, desc="Translating...")

    try:
        threads = int(threads)
    except ValueError:
        threads = 1

    param = {
        "files": [str(file_raw)],
        "pages": selected_page,
        "lang_in": lang_from,
        "lang_out": lang_to,
        "service": f"{translator.name}",
        "output": output,
        "thread": int(threads),
        "callback": progress_bar,
        "cancellation_event": cancellation_event_map[session_id],
        "envs": _envs,
        "prompt": Template(prompt) if prompt else None,
        "skip_subset_fonts": skip_subset_fonts,
        "model": ModelInstance.value,
    }
    try:
        translate(**param)
    except CancelledError:
        del cancellation_event_map[session_id]
        raise gr.Error("Translation cancelled")
    print(f"Files after translation: {os.listdir(output)}")

    if not file_mono.exists() or not file_dual.exists():
        raise gr.Error("No output")

    progress(1.0, desc="Translation complete!")

    return (
        str(file_mono),
        str(file_mono),
        str(file_dual),
        gr.update(visible=True),
        gr.update(visible=True),
        gr.update(visible=True),
    )


# Global setup
custom_blue = gr.themes.Color(
    c50="#E8F3FF",
    c100="#BEDAFF",
    c200="#94BFFF",
    c300="#6AA1FF",
    c400="#4080FF",
    c500="#165DFF",  # Primary color
    c600="#0E42D2",
    c700="#0A2BA6",
    c800="#061D79",
    c900="#03114D",
    c950="#020B33",
)

custom_css = """
    .secondary-text {color: #999 !important;}
    footer {visibility: hidden}
    .env-warning {color: #dd5500 !important;}
    .env-success {color: #559900 !important;}

    /* Add dashed border to input-file class */
    .input-file {
        border: 1.2px dashed #165DFF !important;
        border-radius: 6px !important;
    }

    .progress-bar-wrap {
        border-radius: 8px !important;
    }

    .progress-bar {
        border-radius: 8px !important;
    }

    .pdf-canvas canvas {
        width: 100%;
    }
    """

demo_recaptcha = """
    <script src="https://www.google.com/recaptcha/api.js?render=explicit" async defer></script>
    <script type="text/javascript">
        var onVerify = function(token) {
            el=document.getElementById('verify').getElementsByTagName('textarea')[0];
            el.value=token;
            el.dispatchEvent(new Event('input'));
        };
    </script>
    """

tech_details_string = f"""
                    <summary>Technical details</summary>
                    - GitHub: <a href="https://github.com/Byaidu/PDFMathTranslate">Byaidu/PDFMathTranslate</a><br>
                    - GUI by: <a href="https://github.com/reycn">Rongxin</a><br>
                    - Version: {__version__}
                """
cancellation_event_map = {}


# The following code creates the GUI
with gr.Blocks(
    title="PDFMathTranslate - PDF Translation with preserved formats",
    theme=gr.themes.Default(
        primary_hue=custom_blue, spacing_size="md", radius_size="lg"
    ),
    css=custom_css,
    head=demo_recaptcha if flag_demo else "",
) as demo:
    gr.Markdown(
        "# [PDFMathTranslate @ GitHub](https://github.com/Byaidu/PDFMathTranslate)"
    )

    with gr.Row():
        with gr.Column(scale=1):
            gr.Markdown("## File | < 5 MB" if flag_demo else "## File")
            file_type = gr.Radio(
                choices=["File", "Link"],
                label="Type",
                value="File",
            )
            file_input = gr.File(
                label="File",
                file_count="single",
                file_types=[".pdf"],
                type="filepath",
                elem_classes=["input-file"],
            )
            link_input = gr.Textbox(
                label="Link",
                visible=False,
                interactive=True,
            )
            gr.Markdown("## Option")
            service = gr.Dropdown(
                label="Service",
                choices=service_map.keys(),
                value="Google",
            )
            envs = []
            for i in range(3):
                envs.append(
                    gr.Textbox(
                        visible=False,
                        interactive=True,
                    )
                )
            with gr.Row():
                lang_from = gr.Dropdown(
                    label="Translate from",
                    choices=lang_map.keys(),
                    value=ConfigManager.get("PDF2ZH_LANG_FROM", "English"),
                )
                lang_to = gr.Dropdown(
                    label="Translate to",
                    choices=lang_map.keys(),
                    value=ConfigManager.get("PDF2ZH_LANG_TO", "Simplified Chinese"),
                )
            page_range = gr.Radio(
                choices=page_map.keys(),
                label="Pages",
                value=list(page_map.keys())[0],
            )

            page_input = gr.Textbox(
                label="Page range",
                visible=False,
                interactive=True,
            )

            with gr.Accordion("Open for More Experimental Options!", open=False):
                gr.Markdown("#### Experimental")
                threads = gr.Textbox(
                    label="number of threads", interactive=True, value="4"
                )
                skip_subset_fonts = gr.Checkbox(
                    label="Skip font subsetting", interactive=True, value=False
                )
                prompt = gr.Textbox(
                    label="Custom Prompt for llm", interactive=True, visible=False
                )
                envs.append(prompt)

            def on_select_service(service, evt: gr.EventData):
                translator = service_map[service]
                _envs = []
                for i in range(4):
                    _envs.append(gr.update(visible=False, value=""))
                for i, env in enumerate(translator.envs.items()):
                    _envs[i] = gr.update(
                        visible=True,
                        label=env[0],
                        value=ConfigManager.get_env_by_translatername(
                            translator, env[0], env[1]
                        ),
                    )
                _envs[-1] = gr.update(visible=translator.CustomPrompt)
                return _envs

            def on_select_filetype(file_type):
                return (
                    gr.update(visible=file_type == "File"),
                    gr.update(visible=file_type == "Link"),
                )

            def on_select_page(choice):
                if choice == "Others":
                    return gr.update(visible=True)
                else:
                    return gr.update(visible=False)

            output_title = gr.Markdown("## Translated", visible=False)
            output_file_mono = gr.File(
                label="Download Translation (Mono)", visible=False
            )
            output_file_dual = gr.File(
                label="Download Translation (Dual)", visible=False
            )
            recaptcha_response = gr.Textbox(
                label="reCAPTCHA Response", elem_id="verify", visible=False
            )
            recaptcha_box = gr.HTML('<div id="recaptcha-box"></div>')
            translate_btn = gr.Button("Translate", variant="primary")
            cancellation_btn = gr.Button("Cancel", variant="secondary")
            tech_details_tog = gr.Markdown(
                tech_details_string,
                elem_classes=["secondary-text"],
            )
            page_range.select(on_select_page, page_range, page_input)
            service.select(
                on_select_service,
                service,
                envs,
            )
            file_type.select(
                on_select_filetype,
                file_type,
                [file_input, link_input],
                js=(
                    f"""
                    (a,b)=>{{
                        try{{
                            grecaptcha.render('recaptcha-box',{{
                                'sitekey':'{client_key}',
                                'callback':'onVerify'
                            }});
                        }}catch(error){{}}
                        return [a];
                    }}
                    """
                    if flag_demo
                    else ""
                ),
            )

        with gr.Column(scale=2):
            gr.Markdown("## Preview")
            preview = PDF(label="Document Preview", visible=True, height=2000)

    # Event handlers
    file_input.upload(
        lambda x: x,
        inputs=file_input,
        outputs=preview,
        js=(
            f"""
            (a,b)=>{{
                try{{
                    grecaptcha.render('recaptcha-box',{{
                        'sitekey':'{client_key}',
                        'callback':'onVerify'
                    }});
                }}catch(error){{}}
                return [a];
            }}
            """
            if flag_demo
            else ""
        ),
    )

    state = gr.State({"session_id": None})

    translate_btn.click(
        translate_file,
        inputs=[
            file_type,
            file_input,
            link_input,
            service,
            lang_from,
            lang_to,
            page_range,
            page_input,
            prompt,
            threads,
            skip_subset_fonts,
            recaptcha_response,
            state,
            *envs,
        ],
        outputs=[
            output_file_mono,
            preview,
            output_file_dual,
            output_file_mono,
            output_file_dual,
            output_title,
        ],
    ).then(lambda: None, js="()=>{grecaptcha.reset()}" if flag_demo else "")

    cancellation_btn.click(
        stop_translate_file,
        inputs=[state],
    )


def parse_user_passwd(file_path: str) -> tuple:
    """
    Parse the user name and password from the file.

    Inputs:
        - file_path: The file path to read.
    Outputs:
        - tuple_list: The list of tuples of user name and password.
        - content: The content of the file
    """
    tuple_list = []
    content = ""
    if not file_path:
        return tuple_list, content
    if len(file_path) == 2:
        try:
            with open(file_path[1], "r", encoding="utf-8") as file:
                content = file.read()
        except FileNotFoundError:
            print(f"Error: File '{file_path[1]}' not found.")
    try:
        with open(file_path[0], "r", encoding="utf-8") as file:
            tuple_list = [
                tuple(line.strip().split(",")) for line in file if line.strip()
            ]
    except FileNotFoundError:
        print(f"Error: File '{file_path[0]}' not found.")
    return tuple_list, content


def setup_gui(
    share: bool = False, auth_file: list = ["", ""], server_port=7860
) -> None:
    """
    Setup the GUI with the given parameters.

    Inputs:
        - share: Whether to share the GUI.
        - auth_file: The file path to read the user name and password.

    Outputs:
        - None
    """
    user_list, html = parse_user_passwd(auth_file)
    if flag_demo:
        demo.launch(server_name="0.0.0.0", max_file_size="5mb", inbrowser=True)
    else:
        if len(user_list) == 0:
            try:
                demo.launch(
                    server_name="0.0.0.0",
                    debug=True,
                    inbrowser=True,
                    share=share,
                    server_port=server_port,
                )
            except Exception:
                print(
                    "Error launching GUI using 0.0.0.0.\nThis may be caused by global mode of proxy software."
                )
                try:
                    demo.launch(
                        server_name="127.0.0.1",
                        debug=True,
                        inbrowser=True,
                        share=share,
                        server_port=server_port,
                    )
                except Exception:
                    print(
                        "Error launching GUI using 127.0.0.1.\nThis may be caused by global mode of proxy software."
                    )
                    demo.launch(
                        debug=True, inbrowser=True, share=True, server_port=server_port
                    )
        else:
            try:
                demo.launch(
                    server_name="0.0.0.0",
                    debug=True,
                    inbrowser=True,
                    share=share,
                    auth=user_list,
                    auth_message=html,
                    server_port=server_port,
                )
            except Exception:
                print(
                    "Error launching GUI using 0.0.0.0.\nThis may be caused by global mode of proxy software."
                )
                try:
                    demo.launch(
                        server_name="127.0.0.1",
                        debug=True,
                        inbrowser=True,
                        share=share,
                        auth=user_list,
                        auth_message=html,
                        server_port=server_port,
                    )
                except Exception:
                    print(
                        "Error launching GUI using 127.0.0.1.\nThis may be caused by global mode of proxy software."
                    )
                    demo.launch(
                        debug=True,
                        inbrowser=True,
                        share=True,
                        auth=user_list,
                        auth_message=html,
                        server_port=server_port,
                    )


# For auto-reloading while developing
if __name__ == "__main__":
    setup_gui()