"""
Document viewer component for displaying PDFs with citation highlighting
"""
from typing import List, Dict, Optional
import json


class DocumentViewer:
    """Handle document viewing with citation highlighting"""
    
    def __init__(self):
        """Initialize document viewer"""
        self.current_document = None
        self.current_highlights = []
    
    def render_document(self, html_content: str, filename: str, highlight_paragraphs: List[str] = None) -> str:
        """
        Render document with optional paragraph highlighting
        
        Args:
            html_content: HTML content of the document
            filename: Name of the document
            highlight_paragraphs: List of paragraph IDs to highlight
            
        Returns:
            Enhanced HTML with highlighting
        """
        if not html_content:
            return self._render_empty_state()
        
        # Add highlighting script and marks
        if highlight_paragraphs:
            for para_id in highlight_paragraphs:
                # Add highlighted class to specific paragraphs
                html_content = html_content.replace(
                    f'<p class="paragraph" id="{para_id}"',
                    f'<p class="paragraph highlighted-citation" id="{para_id}"'
                )
        
        # Wrap with viewer container and add controls
        enhanced_html = f"""
        <div class="document-viewer-wrapper">
            {self._create_viewer_controls(filename)}
            <div class="document-viewer-content" id="doc-viewer-content">
                {html_content}
            </div>
        </div>
        
        <script>
        // Auto-scroll to first highlighted paragraph
        document.addEventListener('DOMContentLoaded', function() {{
            const firstHighlight = document.querySelector('.highlighted-citation');
            if (firstHighlight) {{
                setTimeout(function() {{
                    firstHighlight.scrollIntoView({{ behavior: 'smooth', block: 'center' }});
                }}, 300);
            }}
        }});
        
        // Smooth scroll when clicking citation links
        function scrollToParagraph(paraId) {{
            const element = document.getElementById(paraId);
            if (element) {{
                // Remove previous highlights
                document.querySelectorAll('.highlighted-citation').forEach(el => {{
                    el.classList.remove('highlighted-citation');
                }});
                
                // Add highlight to clicked citation
                element.classList.add('highlighted-citation');
                
                // Scroll to element
                element.scrollIntoView({{ behavior: 'smooth', block: 'center' }});
                
                // Flash effect
                element.style.animation = 'none';
                setTimeout(() => {{
                    element.style.animation = 'highlight-flash 1s ease';
                }}, 10);
            }}
        }}
        </script>
        """
        
        return enhanced_html
    
    def _create_viewer_controls(self, filename: str) -> str:
        """
        Create viewer control bar
        
        Args:
            filename: Current document filename
            
        Returns:
            HTML for controls
        """
        return f"""
        <div class="viewer-controls">
            <div class="viewer-title">
                <span class="doc-icon">📄</span>
                <span class="doc-name">{filename}</span>
            </div>
            <div class="viewer-actions">
                <button class="viewer-btn" onclick="document.getElementById('doc-viewer-content').style.fontSize='0.9em';" title="Zoom Out">
                    🔍−
                </button>
                <button class="viewer-btn" onclick="document.getElementById('doc-viewer-content').style.fontSize='1em';" title="Reset Zoom">
                    🔍
                </button>
                <button class="viewer-btn" onclick="document.getElementById('doc-viewer-content').style.fontSize='1.1em';" title="Zoom In">
                    🔍+
                </button>
            </div>
        </div>
        """
    
    def _render_empty_state(self) -> str:
        """
        Render empty state when no document is selected
        
        Returns:
            HTML for empty state
        """
        return """
        <div class="document-viewer-empty">
            <div class="empty-state-icon">📄</div>
            <h3>Tidak Ada Dokumen</h3>
            <p>Upload dokumen PDF untuk melihat konten dan sitasi di sini.</p>
        </div>
        """
    
    def create_citation_link(self, filename: str, paragraph_ids: List[str], snippet: str, page: int = None) -> str:
        """
        Create clickable citation link for chat
        
        Args:
            filename: Source document filename
            paragraph_ids: List of paragraph IDs this citation refers to
            snippet: Text snippet to show
            page: Page number (optional)
            
        Returns:
            HTML citation link
        """
        para_id = paragraph_ids[0] if paragraph_ids else "unknown"
        page_info = f" (Hal. {page})" if page else ""
        
        citation_html = f"""
        <div class="citation-card" onclick="scrollToParagraph('{para_id}')">
            <div class="citation-header">
                <strong>📄 {filename}{page_info}</strong>
            </div>
            <div class="citation-snippet">
                "{snippet[:150]}..."
            </div>
        </div>
        """
        
        return citation_html
    
    def format_sources_with_links(self, sources: List[Dict]) -> tuple[str, List[str]]:
        """
        Format sources as interactive citations
        
        Args:
            sources: List of source metadata from RAG pipeline
            
        Returns:
            Tuple of (HTML string, list of paragraph IDs to highlight)
        """
        if not sources:
            return "", []
        
        all_paragraph_ids = []
        html = "<div class='sources-container'>"
        html += "<h4 class='sources-title'>📚 Sumber Referensi:</h4>"
        
        for i, source in enumerate(sources, 1):
            filename = source.get('filename', 'Unknown')
            chunk_text = source.get('chunk_text', '')
            
            # Parse paragraph IDs if available
            paragraph_ids_str = source.get('paragraph_ids', '[]')
            try:
                if isinstance(paragraph_ids_str, str):
                    paragraph_ids = json.loads(paragraph_ids_str)
                else:
                    paragraph_ids = paragraph_ids_str if isinstance(paragraph_ids_str, list) else []
            except:
                paragraph_ids = []
            
            # Parse pages
            pages_str = source.get('pages', '[]')
            try:
                if isinstance(pages_str, str):
                    pages = json.loads(pages_str)
                else:
                    pages = pages_str if isinstance(pages_str, list) else []
            except:
                pages = []
            
            page = pages[0] if pages else None
            
            # Track all paragraph IDs for highlighting
            all_paragraph_ids.extend(paragraph_ids)
            
            # Create citation link
            html += self.create_citation_link(
                filename=filename,
                paragraph_ids=paragraph_ids,
                snippet=chunk_text,
                page=page
            )
        
        html += "</div>"
        
        return html, list(set(all_paragraph_ids))  # Return unique paragraph IDs
    
    def create_document_selector(self, documents: List[Dict], current_doc: str = None) -> str:
        """
        Create dropdown selector for documents
        
        Args:
            documents: List of document metadata
            current_doc: Currently selected document filename
            
        Returns:
            HTML for document selector
        """
        if not documents:
            return "<p class='no-docs-message'>Belum ada dokumen yang tersedia</p>"
        
        html = """
        <div class="document-selector">
            <label for="doc-select">Pilih Dokumen:</label>
            <select id="doc-select" class="doc-select-dropdown">
        """
        
        for doc in documents:
            filename = doc.get('filename', 'Unknown')
            num_pages = doc.get('num_pages', 0)
            selected = 'selected' if filename == current_doc else ''
            
            html += f"""
                <option value="{filename}" {selected}>
                    {filename} ({num_pages} hal.)
                </option>
            """
        
        html += """
            </select>
        </div>
        """
        
        return html