web_utils.py

"""
Web utilities for search, content extraction, and URL handling.
"""

import os
import re
import requests
from urllib.parse import urlparse, urljoin
from bs4 import BeautifulSoup
import html2text
from typing import Optional, Dict, Tuple, List
import time

from tavily import TavilyClient
from config import TAVILY_API_KEY

# Initialize Tavily client if API key is available
tavily_client = None
if TAVILY_API_KEY:
    try:
        tavily_client = TavilyClient(api_key=TAVILY_API_KEY)
        print("[WebUtils] Tavily client initialized successfully")
    except Exception as e:
        print(f"[WebUtils] Failed to initialize Tavily client: {e}")
        tavily_client = None
else:
    print("[WebUtils] Tavily API key not found - web search will be unavailable")

class WebContentExtractor:
    """Handles web content extraction and processing"""
    
    @staticmethod
    def extract_website_content(url: str) -> str:
        """Extract HTML code and content from a website URL"""
        try:
            # Validate and normalize URL
            parsed_url = urlparse(url)
            if not parsed_url.scheme:
                url = "https://" + url
                parsed_url = urlparse(url)
            
            if not parsed_url.netloc:
                return "Error: Invalid URL provided"
            
            print(f"[WebExtract] Fetching content from: {url}")
            
            # Set comprehensive headers
            headers = {
                'User-Agent': 'Mozilla/5.0 (Macintosh; Intel Mac OS X 10_15_7) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36',
                'Accept': 'text/html,application/xhtml+xml,application/xml;q=0.9,image/webp,image/apng,*/*;q=0.8',
                'Accept-Language': 'en-US,en;q=0.9',
                'Accept-Encoding': 'gzip, deflate, br',
                'DNT': '1',
                'Connection': 'keep-alive',
                'Upgrade-Insecure-Requests': '1',
                'Sec-Fetch-Dest': 'document',
                'Sec-Fetch-Mode': 'navigate',
                'Sec-Fetch-Site': 'none',
                'Sec-Fetch-User': '?1',
                'Cache-Control': 'max-age=0'
            }
            
            # Create session for cookie handling
            session = requests.Session()
            session.headers.update(headers)
            
            # Retry logic for resilient fetching
            max_retries = 3
            for attempt in range(max_retries):
                try:
                    response = session.get(url, timeout=15, allow_redirects=True)
                    response.raise_for_status()
                    break
                except requests.exceptions.HTTPError as e:
                    if e.response.status_code == 403 and attempt < max_retries - 1:
                        # Try different User-Agent on 403
                        session.headers['User-Agent'] = 'Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/120.0.0.0 Safari/537.36'
                        continue
                    else:
                        raise
            
            # Handle encoding properly
            try:
                response.encoding = response.apparent_encoding
                raw_html = response.text
            except:
                raw_html = response.content.decode('utf-8', errors='ignore')
            
            # Parse with BeautifulSoup
            soup = BeautifulSoup(raw_html, 'html.parser')
            
            # Extract metadata
            title = soup.find('title')
            title_text = title.get_text().strip() if title else "No title found"
            
            meta_desc = soup.find('meta', attrs={'name': 'description'})
            description = meta_desc.get('content', '') if meta_desc else ""
            
            # Fix image URLs to absolute URLs
            WebContentExtractor._fix_image_urls(soup, url)
            
            # Extract and analyze content
            content_info = WebContentExtractor._analyze_content(soup)
            
            # Get the modified HTML with absolute URLs
            modified_html = str(soup)
            
            # Clean and format HTML
            cleaned_html = WebContentExtractor._clean_html(modified_html)
            
            # Generate comprehensive website analysis
            website_content = WebContentExtractor._format_website_analysis(
                url, title_text, description, content_info, cleaned_html
            )
            
            return website_content.strip()
            
        except requests.exceptions.HTTPError as e:
            return WebContentExtractor._handle_http_error(e, url)
        except requests.exceptions.Timeout:
            return "Error: Request timed out. The website may be slow or unavailable."
        except requests.exceptions.ConnectionError:
            return "Error: Could not connect to the website. Please check your internet connection and the URL."
        except requests.exceptions.RequestException as e:
            return f"Error accessing website: {str(e)}"
        except Exception as e:
            return f"Error extracting website content: {str(e)}"
    
    @staticmethod
    def _fix_image_urls(soup: BeautifulSoup, base_url: str):
        """Fix relative image URLs to absolute URLs"""
        img_elements = soup.find_all('img')
        for img in img_elements:
            src = img.get('src', '')
            if src:
                img['src'] = WebContentExtractor._make_absolute_url(src, base_url)
                
            # Handle lazy loading images
            data_src = img.get('data-src', '')
            if data_src and not src:
                img['src'] = WebContentExtractor._make_absolute_url(data_src, base_url)
        
        # Fix background images in style attributes
        elements_with_style = soup.find_all(attrs={'style': True})
        for element in elements_with_style:
            style_attr = element.get('style', '')
            bg_pattern = r'background-image:\s*url\(["\']?([^"\']+)["\']?\)'
            matches = re.findall(bg_pattern, style_attr, re.IGNORECASE)
            for match in matches:
                if match:
                    absolute_bg = WebContentExtractor._make_absolute_url(match, base_url)
                    style_attr = style_attr.replace(match, absolute_bg)
            element['style'] = style_attr
        
        # Fix CSS background images
        style_elements = soup.find_all('style')
        for style in style_elements:
            if style.string:
                style_content = style.string
                bg_pattern = r'background-image:\s*url\(["\']?([^"\']+)["\']?\)'
                matches = re.findall(bg_pattern, style_content, re.IGNORECASE)
                for match in matches:
                    if match:
                        absolute_bg = WebContentExtractor._make_absolute_url(match, base_url)
                        style_content = style_content.replace(match, absolute_bg)
                style.string = style_content
    
    @staticmethod
    def _make_absolute_url(url: str, base_url: str) -> str:
        """Convert relative URL to absolute URL"""
        if url.startswith('//'):
            return 'https:' + url
        elif url.startswith('/'):
            return urljoin(base_url, url)
        elif not url.startswith(('http://', 'https://')):
            return urljoin(base_url, url)
        return url
    
    @staticmethod
    def _analyze_content(soup: BeautifulSoup) -> Dict:
        """Analyze website content and structure"""
        content_sections = []
        nav_links = []
        images = []
        
        # Extract main content areas
        main_selectors = [
            'main', 'article', '.content', '.main-content', '.post-content',
            '#content', '#main', '.entry-content', '.post-body'
        ]
        
        for selector in main_selectors:
            elements = soup.select(selector)
            for element in elements:
                text = element.get_text().strip()
                if len(text) > 100:
                    content_sections.append(text)
        
        # Extract navigation
        nav_elements = soup.find_all(['nav', 'header'])
        for nav in nav_elements:
            links = nav.find_all('a')
            for link in links:
                link_text = link.get_text().strip()
                link_href = link.get('href', '')
                if link_text and link_href:
                    nav_links.append(f"{link_text}: {link_href}")
        
        # Extract images
        img_elements = soup.find_all('img')
        for img in img_elements:
            src = img.get('src', '')
            alt = img.get('alt', '')
            if src:
                images.append({'src': src, 'alt': alt})
        
        # Test image accessibility
        working_images = []
        for img in images[:10]:  # Test first 10 images
            if WebContentExtractor._test_image_url(img['src']):
                working_images.append(img)
        
        print(f"[WebExtract] Found {len(images)} images, {len(working_images)} working")
        
        return {
            'content_sections': content_sections,
            'nav_links': nav_links,
            'images': images,
            'working_images': working_images,
            'script_tags': len(soup.find_all('script'))
        }
    
    @staticmethod
    def _test_image_url(img_url: str) -> bool:
        """Test if image URL is accessible"""
        try:
            test_response = requests.head(img_url, timeout=5, allow_redirects=True)
            return test_response.status_code == 200
        except:
            return False
    
    @staticmethod
    def _clean_html(html_content: str) -> str:
        """Clean and format HTML for better readability"""
        # Remove comments and normalize whitespace
        cleaned = re.sub(r'<!--.*?-->', '', html_content, flags=re.DOTALL)
        cleaned = re.sub(r'\s+', ' ', cleaned)
        cleaned = re.sub(r'>\s+<', '><', cleaned)
        
        # Limit size to avoid token limits
        if len(cleaned) > 15000:
            cleaned = cleaned[:15000] + "\n<!-- ... HTML truncated for length ... -->"
        
        return cleaned
    
    @staticmethod
    def _format_website_analysis(url: str, title: str, description: str, 
                                content_info: Dict, html: str) -> str:
        """Format comprehensive website analysis"""
        working_images = content_info['working_images']
        all_images = content_info['images']
        
        content = f"""
WEBSITE REDESIGN - ORIGINAL HTML CODE
=====================================

URL: {url}
Title: {title}
Description: {description}

PAGE ANALYSIS:
- Website type: {title.lower()} website
- Content sections: {len(content_info['content_sections'])}
- Navigation links: {len(content_info['nav_links'])}
- Total images: {len(all_images)}
- Working images: {len(working_images)}
- JavaScript complexity: {"High" if content_info['script_tags'] > 10 else "Low to Medium"}

WORKING IMAGES (use these URLs in your redesign):
{chr(10).join([f"• {img['alt'] or 'Image'} - {img['src']}" for img in working_images[:20]]) if working_images else "No working images found"}

ALL IMAGES (including potentially broken ones):
{chr(10).join([f"• {img['alt'] or 'Image'} - {img['src']}" for img in all_images[:20]]) if all_images else "No images found"}

ORIGINAL HTML CODE (use this as the base for redesign):
```html
{html}
```

REDESIGN INSTRUCTIONS:
Please redesign this website with a modern, responsive layout while:
1. Preserving all the original content and structure
2. Maintaining the same navigation and functionality  
3. Using the original images and their URLs (listed above)
4. Creating a modern, clean design with improved typography and spacing
5. Making it fully responsive for mobile devices
6. Using modern CSS frameworks and best practices
7. Keeping the same semantic structure but with enhanced styling

IMPORTANT: All image URLs have been converted to absolute URLs and are ready to use. 
Preserve these exact image URLs in your redesigned version.

The HTML code above contains the complete original website structure with all images properly linked.
Use it as your starting point and create a modernized version.
"""
        return content
    
    @staticmethod
    def _handle_http_error(error, url: str) -> str:
        """Handle HTTP errors with user-friendly messages"""
        status_code = error.response.status_code if hasattr(error, 'response') else 0
        
        if status_code == 403:
            return f"Error: Website blocked access (403 Forbidden). This website may have anti-bot protection. Try a different website or provide a description instead."
        elif status_code == 404:
            return f"Error: Website not found (404). Please check the URL and try again."
        elif status_code >= 500:
            return f"Error: Website server error ({status_code}). Please try again later."
        else:
            return f"Error accessing website: HTTP {status_code} - {str(error)}"

class WebSearchEngine:
    """Handles web search operations using Tavily"""
    
    @staticmethod
    def perform_web_search(query: str, max_results: int = 5, 
                          include_domains: Optional[List[str]] = None,
                          exclude_domains: Optional[List[str]] = None) -> str:
        """Perform web search using Tavily with advanced parameters"""
        if not tavily_client:
            return "Web search is not available. Please set the TAVILY_API_KEY environment variable."
        
        try:
            print(f"[WebSearch] Searching for: {query}")
            
            # Configure search parameters
            search_params = {
                "search_depth": "advanced",
                "max_results": min(max(1, max_results), 20),
                "include_answer": True,
                "include_raw_content": False
            }
            
            if include_domains:
                search_params["include_domains"] = include_domains
            if exclude_domains:
                search_params["exclude_domains"] = exclude_domains
            
            # Perform search with timeout
            response = tavily_client.search(query, **search_params)
            
            # Process results
            search_results = []
            answer = response.get('answer', '')
            
            if answer:
                search_results.append(f"Direct Answer: {answer}\n")
            
            for result in response.get('results', []):
                title = result.get('title', 'No title')
                url = result.get('url', 'No URL')
                content = result.get('content', 'No content')
                score = result.get('score', 0)
                
                result_text = (
                    f"Title: {title}\n"
                    f"URL: {url}\n"
                    f"Relevance Score: {score:.2f}\n"
                    f"Content: {content}\n"
                )
                search_results.append(result_text)
            
            if search_results:
                final_results = "Web Search Results:\n\n" + "\n---\n".join(search_results)
                print(f"[WebSearch] Found {len(search_results)} results")
                return final_results
            else:
                return "No search results found."
                
        except Exception as e:
            error_msg = f"Search error: {str(e)}"
            print(f"[WebSearch] Error: {error_msg}")
            return error_msg
    
    @staticmethod
    def enhance_query_with_search(query: str, enable_search: bool) -> str:
        """Enhance the query with web search results if search is enabled"""
        if not enable_search or not tavily_client:
            return query
        
        print("[WebSearch] Enhancing query with web search")
        
        # Perform search to get relevant information
        search_results = WebSearchEngine.perform_web_search(query, max_results=3)
        
        # Combine original query with search results
        enhanced_query = f"""Original Query: {query}

{search_results}

Please use the search results above to help create the requested application with the most up-to-date information and best practices."""
        
        return enhanced_query

# URL parsing utilities
def parse_repo_or_model_url(url: str) -> Tuple[str, Optional[Dict]]:
    """Parse a URL and detect if it's a GitHub repo, HF Space, or HF Model"""
    try:
        parsed = urlparse(url.strip())
        netloc = (parsed.netloc or "").lower()
        path = (parsed.path or "").strip("/")
        
        # Hugging Face spaces
        if ("huggingface.co" in netloc or netloc.endswith("hf.co")) and path.startswith("spaces/"):
            parts = path.split("/")
            if len(parts) >= 3:
                return "hf_space", {"username": parts[1], "project": parts[2]}
        
        # Hugging Face model repo
        if ("huggingface.co" in netloc or netloc.endswith("hf.co")) and not path.startswith(("spaces/", "datasets/", "organizations/")):
            parts = path.split("/")
            if len(parts) >= 2:
                repo_id = f"{parts[0]}/{parts[1]}"
                return "hf_model", {"repo_id": repo_id}
        
        # GitHub repo
        if "github.com" in netloc:
            parts = path.split("/")
            if len(parts) >= 2:
                return "github", {"owner": parts[0], "repo": parts[1]}
                
    except Exception:
        pass
    
    return "unknown", None

def check_hf_space_url(url: str) -> Tuple[bool, Optional[str], Optional[str]]:
    """Check if URL is a valid Hugging Face Spaces URL and extract username/project"""
    url_pattern = re.compile(
        r'^(https?://)?(huggingface\.co|hf\.co)/spaces/([\w-]+)/([\w-]+)$',
        re.IGNORECASE
    )
    
    match = url_pattern.match(url.strip())
    if match:
        username = match.group(3)
        project_name = match.group(4)
        return True, username, project_name
    return False, None, None

# Export main functions
web_extractor = WebContentExtractor()
web_search = WebSearchEngine()

def extract_website_content(url: str) -> str:
    return web_extractor.extract_website_content(url)

def perform_web_search(query: str, max_results: int = 5) -> str:
    return web_search.perform_web_search(query, max_results)

def enhance_query_with_search(query: str, enable_search: bool) -> str:
    return web_search.enhance_query_with_search(query, enable_search)