Update app.py

app.py

@@ -1,112 +1,742 @@
-async def download_papers(bib_file, doi_input, dois_input, progress=gr.Progress()):
-    if bib_file:
-        # Check file type
-        if not bib_file.name.lower().endswith('.bib'):
-            return None, "Error: Please upload a .bib file", "Error: Please upload a .bib file", None
-
-        zip_path, downloaded_dois, failed_dois, _ = await downloader.process_bibtex_async(bib_file, progress)
-        return zip_path, downloaded_dois, failed_dois, None
-    elif doi_input:
-        filepath, message, failed_doi = downloader.download_single_doi(doi_input, progress)
-        return None, message, failed_doi, filepath
-    elif dois_input:
-        zip_path, downloaded_dois, failed_dois = downloader.download_multiple_dois(dois_input, progress)
-        return zip_path, downloaded_dois, failed_dois, None
-    else:
-        return None, "Please provide a .bib file, a single DOI, or a list of DOIs", "Please provide a .bib file, a single DOI, or a list of DOIs", None
-
-# Gradio Interface
-interface = gr.Interface(
-    fn=download_papers,
-    inputs=[
-        gr.File(file_types=['.bib'], label="Upload BibTeX File"),
-        gr.Textbox(label="Enter Single DOI", placeholder="10.xxxx/xxxx"),
-        gr.Textbox(label="Enter Multiple DOIs (one per line)", placeholder="10.xxxx/xxxx\n10.yyyy/yyyy\n...")
-    ],
-    outputs=[
-        gr.File(label="Download Papers (ZIP) or Single PDF"),
-        gr.HTML(label="""
-            <div style='padding-bottom: 5px; font-weight: bold;'>
-                Found DOIs
-            </div>
-            <div style='border: 1px solid #ddd; padding: 5px; border-radius: 5px;'>
-                <div id="downloaded-dois"></div>
-            </div>
-        """),
-        gr.HTML(label="""
-            <div style='padding-bottom: 5px; font-weight: bold;'>
-                Missed DOIs
-            </div>
-            <div style='border: 1px solid #ddd; padding: 5px; border-radius: 5px;'>
-                <div id="failed-dois"></div>
-            </div>
-        """),
-        gr.File(label="Downloaded Single PDF")
-    ],
-    title="🔬 Academic Paper Batch Downloader",
-    description="Upload a BibTeX file or enter DOIs to download PDFs. We'll attempt to fetch PDFs from multiple sources like Sci-Hub, Libgen, Google Scholar and Crossref. You can use any of the three inputs at any moment.",
-    theme="Hev832/Applio",
-    examples=[
-        ["example.bib", None, None],  # Bibtex File
-        [None, "10.1038/nature12373", None],  # Single DOI
-        [None, None, "10.1109/5.771073\n10.3390/horticulturae8080677"],  # Multiple DOIs
-    ],
-    css="""
-    .gradio-container {
-        background-color: black;
-    }
-    .gr-interface {
-        max-width: 800px;
-        margin: 0 auto;
-    }
-    .gr-box {
-        background-color: black;
-        border-radius: 10px;
-        box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
-    }
-       .output-text a {
-           color: #007bff; /* Blue color for hyperlinks */
+import os
+import re
+import time
+import logging
+import zipfile
+import requests
+import bibtexparser
+from tqdm import tqdm
+from urllib.parse import quote, urlencode
+import gradio as gr
+from bs4 import BeautifulSoup
+import io
+import asyncio
+import aiohttp
+
+# Configure logging
+logging.basicConfig(level=logging.INFO,
+                    format='%(asctime)s - %(levelname)s: %(message)s')
+logger = logging.getLogger(__name__)
+
+
+class PaperDownloader:
+    def __init__(self, output_dir='papers'):
+        self.output_dir = output_dir
+        os.makedirs(output_dir, exist_ok=True)
+
+        # Updated download sources
+        self.download_sources = [
+            'https://sci-hub.ee/',
+            'https://sci-hub.st/',
+            'https://sci-hub.ru/',
+            'https://sci-hub.ren/',
+            'https://sci-hub.mksa.top/',
+            'https://sci-hub.se/',
+            'https://libgen.rs/scimag/'
+        ]
+
+        # Request headers
+        self.headers = {
+            'User-Agent': 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/114.0.0.0 Safari/537.36',
+            'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/avif,image/webp,*/*;q=0.8',
+            'Accept-Language': 'en-US,en;q=0.9',
+        }
+
+    def clean_doi(self, doi):
+        """Clean and encode DOI for URL"""
+        if not isinstance(doi, str):
+            return None
+        return quote(doi.strip()) if doi else None
+
+    async def fetch_with_headers(self, session, url, timeout=10):
+        """Utility method to fetch an URL with headers and timeout"""
+        try:
+            async with session.get(url, headers=self.headers, timeout=timeout, allow_redirects=True) as response:
+                response.raise_for_status()
+                return await response.text(), response.headers
+        except Exception as e:
+            logger.debug(f"Error fetching {url}: {e}")
+            return None, None
+    
+    
+    async def download_paper_direct_doi_async(self, session, doi):
+      """Attempt to download the pdf from the landing page of the doi"""
+      if not doi:
+         return None
+      
+      try:
+         doi_url = f"https://doi.org/{self.clean_doi(doi)}"
+         text, headers = await self.fetch_with_headers(session, doi_url, timeout=15)
+         if not text:
+            return None
+
+         pdf_patterns = [
+           r'(https?://[^\s<>"]+?\.pdf)',
+           r'(https?://[^\s<>"]+?download/[^\s<>"]+)',
+           r'(https?://[^\s<>"]+?\/pdf\/[^\s<>"]+)',
+         ]
+            
+         pdf_urls = []
+         for pattern in pdf_patterns:
+            pdf_urls.extend(re.findall(pattern, text))
+
+         for pdf_url in pdf_urls:
+           try:
+               pdf_response = await session.get(pdf_url, headers=self.headers, timeout=10)
+               if 'application/pdf' in pdf_response.headers.get('Content-Type', ''):
+                    logger.debug(f"Found PDF from: {pdf_url}")
+                    return await pdf_response.read()
+           except Exception as e:
+               logger.debug(f"Error downloading PDF from {pdf_url}: {e}")
+
+
+      except Exception as e:
+           logger.debug(f"Error trying to get the PDF from {doi}: {e}")
+      
+      return None
+
+    async def download_paper_scihub_async(self, session, doi):
+        """Improved method to download paper from Sci-Hub using async requests"""
+        if not doi:
+            logger.warning("DOI not provided")
+            return None
+
+        for base_url in self.download_sources:
+            try:
+                scihub_url = f"{base_url}{self.clean_doi(doi)}"
+                text, headers = await self.fetch_with_headers(session, scihub_url, timeout=15)
+                if not text:
+                    continue
+
+                # Search for multiple PDF URL patterns
+                pdf_patterns = [
+                    r'(https?://[^\s<>"]+?\.pdf)',
+                    r'(https?://[^\s<>"]+?download/[^\s<>"]+)',
+                    r'(https?://[^\s<>"]+?\/pdf\/[^\s<>"]+)',
+                ]
+
+                pdf_urls = []
+                for pattern in pdf_patterns:
+                    pdf_urls.extend(re.findall(pattern, text))
+
+                # Try downloading from found URLs
+                for pdf_url in pdf_urls:
+                    try:
+                        pdf_response = await session.get(pdf_url, headers=self.headers, timeout=10)
+                        # Verify if it's a PDF
+                        if 'application/pdf' in pdf_response.headers.get('Content-Type', ''):
+                            logger.debug(f"Found PDF from: {pdf_url}")
+                            return await pdf_response.read()
+                    except Exception as e:
+                        logger.debug(f"Error downloading PDF from {pdf_url}: {e}")
+
+            except Exception as e:
+                logger.debug(f"Error trying to download {doi} from {base_url}: {e}")
+
+        return None
+
+    async def download_paper_libgen_async(self, session, doi):
+        """Download from Libgen, handles the query and the redirection"""
+        if not doi:
+            return None
+
+        base_url = 'https://libgen.rs/scimag/'
+        try:
+            search_url = f"{base_url}?q={self.clean_doi(doi)}"
+            text, headers = await self.fetch_with_headers(session, search_url, timeout=10)
+
+            if not text or "No results" in text:
+                logger.debug(f"No results for DOI: {doi} on libgen")
+                return None
+
+            soup = BeautifulSoup(text, 'html.parser')
+
+            links = soup.select('table.c > tbody > tr:nth-child(2) > td:nth-child(1) > a')
+
+            if links:
+                link = links[0]
+                pdf_url = link['href']
+                pdf_response = await session.get(pdf_url, headers=self.headers, allow_redirects=True, timeout=10)
+                if 'application/pdf' in pdf_response.headers.get('Content-Type', ''):
+                    logger.debug(f"Found PDF from: {pdf_url}")
+                    return await pdf_response.read()
+        except Exception as e:
+            logger.debug(f"Error trying to download {doi} from libgen: {e}")
+        return None
+
+    async def download_paper_google_scholar_async(self, session, doi):
+        """Search google scholar to find an article with the given doi, try to get the pdf"""
+        if not doi:
+            return None
+
+        try:
+            query = f'doi:"{doi}"'
+            params = {'q': query}
+            url = f'https://scholar.google.com/scholar?{urlencode(params)}'
+
+            text, headers = await self.fetch_with_headers(session, url, timeout=10)
+            if not text:
+                return None
+
+            soup = BeautifulSoup(text, 'html.parser')
+
+            # Find any links with [PDF]
+            links = soup.find_all('a', string=re.compile(r'\[PDF\]', re.IGNORECASE))
+
+            if links:
+                pdf_url = links[0]['href']
+                pdf_response = await session.get(pdf_url, headers=self.headers, timeout=10)
+                if 'application/pdf' in pdf_response.headers.get('Content-Type', ''):
+                    logger.debug(f"Found PDF from: {pdf_url}")
+                    return await pdf_response.read()
+        except Exception as e:
+            logger.debug(f"Google Scholar error for {doi}: {e}")
+
+        return None
+
+    async def download_paper_crossref_async(self, session, doi):
+        """Alternative search method using Crossref"""
+        if not doi:
+            return None
+
+        try:
+            # Search for open access link
+            url = f"https://api.crossref.org/works/{doi}"
+            response = await session.get(url, headers=self.headers, timeout=10)
+
+            if response.status == 200:
+                data = await response.json()
+                work = data.get('message', {})
+
+                # Search for open access links
+                links = work.get('link', [])
+                for link in links:
+                    if link.get('content-type') == 'application/pdf':
+                        pdf_url = link.get('URL')
+                        if pdf_url:
+                            pdf_response = await session.get(pdf_url, headers=self.headers)
+                            if 'application/pdf' in pdf_response.headers.get('Content-Type', ''):
+                                logger.debug(f"Found PDF from: {pdf_url}")
+                                return await pdf_response.read()
+
+        except Exception as e:
+            logger.debug(f"Crossref error for {doi}: {e}")
+
+        return None
+
+    async def download_with_retry_async(self, doi, max_retries=3, initial_delay=2):
+        """Downloads a paper using multiple strategies with exponential backoff and async requests"""
+        pdf_content = None
+        retries = 0
+        delay = initial_delay
+
+        async with aiohttp.ClientSession() as session:
+            while retries < max_retries and not pdf_content:
+                try:
+                    pdf_content = (
+                        await self.download_paper_direct_doi_async(session, doi) or
+                        await self.download_paper_scihub_async(session, doi) or
+                        await self.download_paper_libgen_async(session, doi) or
+                        await self.download_paper_google_scholar_async(session, doi) or
+                        await self.download_paper_crossref_async(session, doi)
+
+                    )
+                    if pdf_content:
+                        return pdf_content
+                except Exception as e:
+                    logger.error(f"Error in download attempt {retries + 1} for DOI {doi}: {e}")
+
+                if not pdf_content:
+                    retries += 1
+                    logger.warning(f"Retry attempt {retries} for DOI: {doi} after {delay} seconds")
+                    await asyncio.sleep(delay)
+                    delay *= 2  # Exponential backoff
+
+        return None
+
+    def download_paper_scihub(self, doi):
+        """Improved method to download paper from Sci-Hub"""
+        if not doi:
+            logger.warning("DOI not provided")
+            return None
+
+        for base_url in self.download_sources:
+            try:
+                scihub_url = f"{base_url}{self.clean_doi(doi)}"
+
+                # Request with more tolerance
+                response = requests.get(scihub_url,
+                                        headers=self.headers,
+                                        allow_redirects=True,
+                                        timeout=15)
+
+                # Search for multiple PDF URL patterns
+                pdf_patterns = [
+                    r'(https?://[^\s<>"]+?\.pdf)',
+                    r'(https?://[^\s<>"]+?download/[^\s<>"]+)',
+                    r'(https?://[^\s<>"]+?\/pdf\/[^\s<>"]+)',
+                ]
+
+                pdf_urls = []
+                for pattern in pdf_patterns:
+                    pdf_urls.extend(re.findall(pattern, response.text))
+
+                # Try downloading from found URLs
+                for pdf_url in pdf_urls:
+                    try:
+                        pdf_response = requests.get(pdf_url,
+                                                    headers=self.headers,
+                                                    timeout=10)
+
+                        # Verify if it's a PDF
+                        if 'application/pdf' in pdf_response.headers.get('Content-Type', ''):
+                            logger.debug(f"Found PDF from: {pdf_url}")
+                            return pdf_response.content
+                    except Exception as e:
+                        logger.debug(f"Error downloading PDF from {pdf_url}: {e}")
+
+            except Exception as e:
+                logger.debug(f"Error trying to download {doi} from {base_url}: {e}")
+
+        return None
+
+    def download_paper_libgen(self, doi):
+        """Download from Libgen, handles the query and the redirection"""
+        if not doi:
+            return None
+
+        base_url = 'https://libgen.rs/scimag/'
+        try:
+            search_url = f"{base_url}?q={self.clean_doi(doi)}"
+            response = requests.get(search_url, headers=self.headers, allow_redirects=True, timeout=10)
+            response.raise_for_status()
+
+            if "No results" in response.text:
+                logger.debug(f"No results for DOI: {doi} on libgen")
+                return None
+
+            soup = BeautifulSoup(response.text, 'html.parser')
+
+            # Find the link using a specific selector
+            links = soup.select('table.c > tbody > tr:nth-child(2) > td:nth-child(1) > a')
+
+            if links:
+                link = links[0]
+                pdf_url = link['href']
+                pdf_response = requests.get(pdf_url, headers=self.headers, allow_redirects=True, timeout=10)
+                if 'application/pdf' in pdf_response.headers.get('Content-Type', ''):
+                    logger.debug(f"Found PDF from: {pdf_url}")
+                    return pdf_response.content
+
+        except Exception as e:
+            logger.debug(f"Error trying to download {doi} from libgen: {e}")
+        return None
+
+    def download_paper_google_scholar(self, doi):
+        """Search google scholar to find an article with the given doi, try to get the pdf"""
+        if not doi:
+            return None
+
+        try:
+            query = f'doi:"{doi}"'
+            params = {'q': query}
+            url = f'https://scholar.google.com/scholar?{urlencode(params)}'
+
+            response = requests.get(url, headers=self.headers, timeout=10)
+            response.raise_for_status()
+
+            soup = BeautifulSoup(response.text, 'html.parser')
+
+            # Find any links with [PDF]
+            links = soup.find_all('a', string=re.compile(r'\[PDF\]', re.IGNORECASE))
+
+            if links:
+                pdf_url = links[0]['href']
+                pdf_response = requests.get(pdf_url, headers=self.headers, timeout=10)
+                if 'application/pdf' in pdf_response.headers.get('Content-Type', ''):
+                    logger.debug(f"Found PDF from: {pdf_url}")
+                    return pdf_response.content
+        except Exception as e:
+            logger.debug(f"Google Scholar error for {doi}: {e}")
+
+        return None
+
+    def download_paper_crossref(self, doi):
+        """Alternative search method using Crossref"""
+        if not doi:
+            return None
+
+        try:
+            # Search for open access link
+            url = f"https://api.crossref.org/works/{doi}"
+            response = requests.get(url, headers=self.headers, timeout=10)
+
+            if response.status_code == 200:
+                data = response.json()
+                work = data.get('message', {})
+
+                # Search for open access links
+                links = work.get('link', [])
+                for link in links:
+                    if link.get('content-type') == 'application/pdf':
+                        pdf_url = link.get('URL')
+                        if pdf_url:
+                            pdf_response = requests.get(pdf_url, headers=self.headers)
+                            if 'application/pdf' in pdf_response.headers.get('Content-Type', ''):
+                                logger.debug(f"Found PDF from: {pdf_url}")
+                                return pdf_response.content
+
+        except Exception as e:
+            logger.debug(f"Crossref error for {doi}: {e}")
+
+        return None
+
+    def download_with_retry(self, doi, max_retries=3, initial_delay=2):
+        """Downloads a paper using multiple strategies with exponential backoff"""
+        pdf_content = None
+        retries = 0
+        delay = initial_delay
+
+        while retries < max_retries and not pdf_content:
+            try:
+                 pdf_content = (
+                     self.download_paper_scihub(doi) or
+                     self.download_paper_libgen(doi) or
+                     self.download_paper_google_scholar(doi) or
+                     self.download_paper_crossref(doi)
+
+                  )
+
+                 if pdf_content:
+                     return pdf_content
+            except Exception as e:
+                logger.error(f"Error in download attempt {retries + 1} for DOI {doi}: {e}")
+
+            if not pdf_content:
+                retries += 1
+                logger.warning(f"Retry attempt {retries} for DOI: {doi} after {delay} seconds")
+                time.sleep(delay)
+                delay *= 2  # Exponential backoff
+
+        return None
+
+    def download_single_doi(self, doi, progress=gr.Progress()):
+        """Downloads a single paper using a DOI with progress bar"""
+        if not doi:
+            return None, "Error: DOI not provided", "Error: DOI not provided"
+
+        try:
+            pdf_content = self.download_with_retry(doi)
+
+            if pdf_content:
+                if doi is None:
+                    return None, "Error: DOI not provided", "Error: DOI not provided"
+                filename = f"{str(doi).replace('/', '_').replace('.', '_')}.pdf"
+                filepath = os.path.join(self.output_dir, filename)
+                with open(filepath, 'wb') as f:
+                    f.write(pdf_content)
+                logger.info(f"Successfully downloaded: {filename}")
+                progress(1)
+                return filepath, f'<div style="display: flex; align-items: center;">✓ <a href="https://doi.org/{doi}">{doi}</a> <button onclick="copyLink(this)">Copy</button></div>', ""
+            else:
+                logger.warning(f"Could not download: {doi}")
+                progress(1)
+                return None, f"Could not download {doi}", f'<div style="display: flex; align-items: center;">❌ <a href="https://doi.org/{doi}">{doi}</a>  <button onclick="copyLink(this)">Copy</button></div>'
+
+        except Exception as e:
+            logger.error(f"Error processing {doi}: {e}")
+            progress(1)
+            return None, f"Error processing {doi}: {e}", f"Error processing {doi}: {e}"
+
+    def download_multiple_dois(self, dois_text, progress=gr.Progress()):
+        """Downloads multiple papers from a list of DOIs with progress bar"""
+        if not dois_text:
+            return None, "Error: No DOIs provided", "Error: No DOIs provided"
+
+        dois = [doi.strip() for doi in dois_text.split('\n') if doi.strip()]
+        if not dois:
+            return None, "Error: No valid DOIs provided", "Error: No valid DOIs provided"
+
+        total_dois = len(dois)
+        downloaded_files = []
+        failed_dois = []
+        downloaded_links = []
+
+        for i, doi in enumerate(dois):
+            filepath, success_message, fail_message = self.download_single_doi(doi, progress=progress)
+            if filepath:
+                # Unique filename for zip
+                filename = f"{str(doi).replace('/', '_').replace('.', '_')}_{i}.pdf"
+                filepath_unique = os.path.join(self.output_dir, filename)
+                os.rename(filepath, filepath_unique)
+                downloaded_files.append(filepath_unique)
+                downloaded_links.append(f'<div style="display: flex; align-items: center;">✓ <a href="https://doi.org/{doi}">{doi}</a>  <button onclick="copyLink(this)">Copy</button></div>')
+
+            else:
+                failed_dois.append(f'<div style="display: flex; align-items: center;">❌ <a href="https://doi.org/{doi}">{doi}</a>  <button onclick="copyLink(this)">Copy</button></div>')
+            progress((i + 1) / total_dois)
+
+
+        if downloaded_files:
+            zip_filename = 'papers.zip'
+            with zipfile.ZipFile(zip_filename, 'w') as zipf:
+                for file_path in downloaded_files:
+                    zipf.write(file_path, arcname=os.path.basename(file_path))
+            logger.info(f"ZIP file created: {zip_filename}")
+
+        return zip_filename if downloaded_files else None, "\n".join(downloaded_links), "\n".join(failed_dois)
+
+    def process_bibtex(self, bib_file, progress=gr.Progress()):
+        """Process BibTeX file and download papers with multiple strategies with progress bar"""
+        # Read BibTeX file content from the uploaded object
+        try:
+            with open(bib_file.name, 'r', encoding='utf-8') as f:
+                bib_content = f.read()
+        except Exception as e:
+            logger.error(f"Error reading uploaded file {bib_file.name}: {e}")
+            return None, f"Error reading uploaded file {bib_file.name}: {e}", f"Error reading uploaded file {bib_file.name}: {e}", None
+
+        # Parse BibTeX data
+        try:
+            bib_database = bibtexparser.loads(bib_content)
+        except Exception as e:
+            logger.error(f"Error parsing BibTeX data: {e}")
+            return None, f"Error parsing BibTeX data: {e}", f"Error parsing BibTeX data: {e}", None
+
+        # Extract DOIs
+        dois = [entry.get('doi') for entry in bib_database.entries if entry.get('doi')]
+        logger.info(f"Found {len(dois)} DOIs to download")
+
+        # Result lists
+        downloaded_files = []
+        failed_dois = []
+        downloaded_links = []
+
+        total_dois = len(dois)
+        # Download PDFs
+        for i, doi in enumerate(dois):
+            try:
+                # Try to download with multiple methods with retries
+                pdf_content = self.download_with_retry(doi)
+
+                # Save PDF
+                if pdf_content:
+                    if doi is None:
+                        return None, "Error: DOI not provided", "Error: DOI not provided", None
+                    filename = f"{str(doi).replace('/', '_').replace('.', '_')}.pdf"
+                    filepath = os.path.join(self.output_dir, filename)
+
+                    with open(filepath, 'wb') as f:
+                        f.write(pdf_content)
+
+                    downloaded_files.append(filepath)
+                    downloaded_links.append(f'<div style="display: flex; align-items: center;">✓ <a href="https://doi.org/{doi}">{doi}</a>  <button onclick="copyLink(this)">Copy</button></div>')
+                    logger.info(f"Successfully downloaded: {filename}")
+                else:
+                    failed_dois.append(f'<div style="display: flex; align-items: center;">❌ <a href="https://doi.org/{doi}">{doi}</a>  <button onclick="copyLink(this)">Copy</button></div>')
+
+            except Exception as e:
+                failed_dois.append(f'<div style="display: flex; align-items: center;">❌ <a href="https://doi.org/{doi}">{doi}</a>  <button onclick="copyLink(this)">Copy</button></div>')
+                logger.error(f"Error processing {doi}: {e}")
+            progress((i + 1) / total_dois)
+
+        # Create ZIP of downloaded papers
+        if downloaded_files:
+            zip_filename = 'papers.zip'
+            with zipfile.ZipFile(zip_filename, 'w') as zipf:
+                for file_path in downloaded_files:
+                    zipf.write(file_path, arcname=os.path.basename(file_path))
+            logger.info(f"ZIP file created: {zip_filename}")
+
+        return zip_filename, "\n".join(downloaded_links), "\n".join(failed_dois), None
+
+    async def process_bibtex_async(self, bib_file, progress=gr.Progress()):
+        """Process BibTeX file and download papers with multiple strategies"""
+        # Read BibTeX file content from the uploaded object
+        try:
+            with open(bib_file.name, 'r', encoding='utf-8') as f:
+                bib_content = f.read()
+        except Exception as e:
+            logger.error(f"Error reading uploaded file {bib_file.name}: {e}")
+            return None, f"Error reading uploaded file {bib_file.name}: {e}", f"Error reading uploaded file {bib_file.name}: {e}", None
+
+        # Parse BibTeX data
+        try:
+            bib_database = bibtexparser.loads(bib_content)
+        except Exception as e:
+            logger.error(f"Error parsing BibTeX data: {e}")
+            return None, f"Error parsing BibTeX data: {e}", f"Error parsing BibTeX data: {e}", None
+
+        # Extract DOIs
+        dois = [entry.get('doi') for entry in bib_database.entries if entry.get('doi')]
+        logger.info(f"Found {len(dois)} DOIs to download")
+
+        # Result lists
+        downloaded_files = []
+        failed_dois = []
+        downloaded_links = []
+
+        total_dois = len(dois)
+        # Download PDFs
+        for i, doi in enumerate(dois):
+            try:
+                # Try to download with multiple methods with retries
+                pdf_content = await self.download_with_retry_async(doi)
+
+                # Save PDF
+                if pdf_content:
+                    if doi is None:
+                        return None, "Error: DOI not provided", "Error: DOI not provided", None
+                    filename = f"{str(doi).replace('/', '_').replace('.', '_')}.pdf"
+                    filepath = os.path.join(self.output_dir, filename)
+
+                    with open(filepath, 'wb') as f:
+                        f.write(pdf_content)
+
+                    downloaded_files.append(filepath)
+                    downloaded_links.append(f'<div style="display: flex; align-items: center;">✓ <a href="https://doi.org/{doi}">{doi}</a>  <button onclick="copyLink(this)">Copy</button></div>')
+                    logger.info(f"Successfully downloaded: {filename}")
+                else:
+                    failed_dois.append(f'<div style="display: flex; align-items: center;">❌ <a href="https://doi.org/{doi}">{doi}</a>  <button onclick="copyLink(this)">Copy</button></div>')
+
+            except Exception as e:
+                failed_dois.append(f'<div style="display: flex; align-items: center;">❌ <a href="https://doi.org/{doi}">{doi}</a>  <button onclick="copyLink(this)">Copy</button></div>')
+                logger.error(f"Error processing {doi}: {e}")
+            progress((i + 1) / total_dois)
+
+
+        # Create ZIP of downloaded papers
+        if downloaded_files:
+            zip_filename = 'papers.zip'
+            with zipfile.ZipFile(zip_filename, 'w') as zipf:
+                for file_path in downloaded_files:
+                    zipf.write(file_path, arcname=os.path.basename(file_path))
+            logger.info(f"ZIP file created: {zip_filename}")
+
+        return zip_filename, "\n".join(downloaded_links), "\n".join(failed_dois), None
+
+def create_gradio_interface():
+    """Create Gradio interface for Paper Downloader"""
+    downloader = PaperDownloader()
+
+    async def download_papers(bib_file, doi_input, dois_input, progress=gr.Progress()):
+        if bib_file:
+            # Check file type
+            if not bib_file.name.lower().endswith('.bib'):
+                return None, "Error: Please upload a .bib file", "Error: Please upload a .bib file", None
+
+            zip_path, downloaded_dois, failed_dois, _ = await downloader.process_bibtex_async(bib_file, progress)
+            return zip_path, downloaded_dois, failed_dois, None
+        elif doi_input:
+            filepath, message, failed_doi = downloader.download_single_doi(doi_input, progress)
+            return None, message, failed_doi, filepath
+        elif dois_input:
+            zip_path, downloaded_dois, failed_dois = downloader.download_multiple_dois(dois_input, progress)
+            return zip_path, downloaded_dois, failed_dois, None
+        else:
+            return None, "Please provide a .bib file, a single DOI, or a list of DOIs", "Please provide a .bib file, a single DOI, or a list of DOIs", None
+
+    # Gradio Interface
+    interface = gr.Interface(
+        fn=download_papers,
+        inputs=[
+            gr.File(file_types=['.bib'], label="Upload BibTeX File"),
+            gr.Textbox(label="Enter Single DOI", placeholder="10.xxxx/xxxx"),
+            gr.Textbox(label="Enter Multiple DOIs (one per line)", placeholder="10.xxxx/xxxx\n10.yyyy/yyyy\n...")
+        ],
+        outputs=[
+            gr.File(label="Download Papers (ZIP) or Single PDF"),
+            gr.HTML(label="""
+                <div style='padding-bottom: 5px; font-weight: bold;'>
+                    Found DOIs
+                </div>
+                <div style='border: 1px solid #ddd; padding: 5px; border-radius: 5px;'>
+                    <div id="downloaded-dois"></div>
+                </div>
+            """),
+            gr.HTML(label="""
+                <div style='padding-bottom: 5px; font-weight: bold;'>
+                    Missed DOIs
+                </div>
+                <div style='border: 1px solid #ddd; padding: 5px; border-radius: 5px;'>
+                    <div id="failed-dois"></div>
+                </div>
+            """),
+            gr.File(label="Downloaded Single PDF")
+        ],
+        title="🔬 Academic Paper Batch Downloader",
+        description="Upload a BibTeX file or enter DOIs to download PDFs. We'll attempt to fetch PDFs from multiple sources like Sci-Hub, Libgen, Google Scholar and Crossref. You can use any of the three inputs at any moment.",
+        theme="Hev832/Applio",
+        examples=[
+            ["example.bib", None, None],  # Bibtex File
+            [None, "10.1038/nature12373", None],  # Single DOI
+            [None, None, "10.1109/5.771073\n10.3390/horticulturae8080677"],  # Multiple DOIs
+        ],
+        css="""
+        .gradio-container {
+            background-color: black;
+        }
+        .gr-interface {
+            max-width: 800px;
+            margin: 0 auto;
+        }
+        .gr-box {
+            background-color: black;
+            border-radius: 10px;
+            box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
         }
-    """,
-    cache_examples=False,
-)
-
-# Add Javascript to update HTML
-interface.load = """
-   function(downloaded_dois, failed_dois) {
-      let downloaded_html = '';
-      downloaded_dois.split('\\n').filter(Boolean).forEach(doi => {
-          downloaded_html +=  doi + '<br>';
-      });
-      document.querySelector("#downloaded-dois").innerHTML = downloaded_html;
-
-      let failed_html = '';
-        failed_dois.split('\\n').filter(Boolean).forEach(doi => {
-        failed_html += doi + '<br>';
-      });
-      document.querySelector("#failed-dois").innerHTML = failed_html;
-      return [downloaded_html, failed_html];
-   }
-"""
-
-interface.head = """
-<script>
-    function copyLink(button) {
-        const linkElement = button.previousElementSibling;
-        const link = linkElement.href;
-        navigator.clipboard.writeText(link)
-        .then(() => {
-            button.innerText = '✓ Copied';
-            button.style.color = 'green';
-            setTimeout(() => {
-                button.innerText = 'Copy';
-                button.style.color = '';
-            }, 2000);
-        })
-        .catch(err => {
-            console.error('Failed to copy link: ', err);
-        });
-    }
-</script>
-"""
-return interface
+           .output-text a {
+               color: #007bff; /* Blue color for hyperlinks */
+            }
+        """,
+        cache_examples=False,
+    )
+
+    # Add Javascript to update HTML
+    interface.load = """
+       function(downloaded_dois, failed_dois) {
+          let downloaded_html = '';
+          downloaded_dois.split('\\n').filter(Boolean).forEach(doi => {
+              downloaded_html +=  doi + '<br>';
+          });
+          document.querySelector("#downloaded-dois").innerHTML = downloaded_html;
+
+          let failed_html = '';
+            failed_dois.split('\\n').filter(Boolean).forEach(doi => {
+            failed_html += doi + '<br>';
+          });
+          document.querySelector("#failed-dois").innerHTML = failed_html;
+          return [downloaded_html, failed_html];
+       }
+    """
+    
+    interface.head = """
+    <script>
+        function copyLink(button) {
+            const linkElement = button.previousElementSibling;
+            const link = linkElement.href;
+            navigator.clipboard.writeText(link)
+            .then(() => {
+                button.innerText = '✓ Copied';
+                button.style.color = 'green';
+                setTimeout(() => {
+                    button.innerText = 'Copy';
+                    button.style.color = '';
+                }, 2000);
+            })
+            .catch(err => {
+                console.error('Failed to copy link: ', err);
+            });
+        }
+    </script>
+    """
+    return interface
+
+
+def main():
+    interface = create_gradio_interface()
+    interface.launch(share=True)
+
+
+if __name__ == "__main__":
+    main()