import React, { useEffect } from "react";
import ReactMarkdown from 'react-markdown';
import { MdClose } from "react-icons/md";
import { Document } from "./dashboardChatAreaTypes";
import { useFilePreview } from "../../../../hooks/useWorkflows";
import styles from './FilePreviewPopup.module.css';

interface FilePreviewPopupProps {
    document: Document;
    isOpen: boolean;
    onClose: () => void;
}

const FilePreviewPopup: React.FC<FilePreviewPopupProps> = ({ document, isOpen, onClose }) => {
    const { previewContent, fileMetadata, isLoading, error, fetchPreview, clearPreview } = useFilePreview();

    useEffect(() => {
        if (isOpen && document) {
            // Use fileId if available, otherwise try to use id as fallback
            const fileId = document.fileId || document.id;
            
            if (fileId) {
                console.log('FilePreviewPopup: calling fetchPreview with fileId:', fileId);
                fetchPreview(String(fileId));
            } else {
                console.error('FilePreviewPopup: No fileId or id available on document:', document);
            }
        } else if (!isOpen) {
            clearPreview();
        }
    }, [isOpen, document.fileId, document.id]);

    const handleBackdropClick = (e: React.MouseEvent) => {
        if (e.target === e.currentTarget) {
            onClose();
        }
    };

    const getPreviewComponent = () => {
        if (isLoading) {
            return <div className={styles.loading}>Loading preview...</div>;
        }

        if (error) {
            return (
                <div className={styles.error}>
                    <div>Error: {error}</div>
                    {fileMetadata && (
                        <div style={{ marginTop: '10px', fontSize: '12px', opacity: 0.7 }}>
                            Debug: {JSON.stringify(fileMetadata, null, 2)}
                        </div>
                    )}
                </div>
            );
        }

        if (!previewContent) {
            return (
                <div className={styles.no_preview}>
                    <div>No preview available</div>
                    {fileMetadata && (
                        <div style={{ marginTop: '10px', fontSize: '12px', opacity: 0.7 }}>
                            Available metadata: {Object.keys(fileMetadata).join(', ')}
                            <br />
                            Preview field: {fileMetadata.preview ? 'has data' : 'empty/null'}
                            <br />
                            Base64Encoded: {String(fileMetadata.base64Encoded)}
                            <br />
                            MimeType: {fileMetadata.mimeType}
                        </div>
                    )}
                </div>
            );
        }

        // Use metadata from backend response
        const mimeType = fileMetadata?.mimeType;
        const isBase64Encoded = fileMetadata?.base64Encoded;
        const fileExtension = document.ext?.toLowerCase();
        
        // Check if this is a markdown file by extension/MIME type first
        const isMarkdownByType = fileExtension === 'md' || 
                                fileExtension === 'markdown' || 
                                mimeType === 'text/markdown' ||
                                mimeType === 'text/x-markdown';
        
        // Content-based markdown detection for .txt files with markdown content
        // BUT NOT for specific code file types
        const isCodeFile = fileExtension === 'py' || 
                          fileExtension === 'js' || 
                          fileExtension === 'ts' || 
                          fileExtension === 'jsx' || 
                          fileExtension === 'tsx' ||
                          fileExtension === 'java' ||
                          fileExtension === 'cpp' ||
                          fileExtension === 'c' ||
                          fileExtension === 'php' ||
                          fileExtension === 'html' ||
                          fileExtension === 'css';
        
        const hasMarkdownContent = !isCodeFile && previewContent && (
            previewContent.includes('# ') ||           // Headers
            previewContent.includes('## ') ||          // Headers
            previewContent.includes('**') ||           // Bold
            previewContent.includes('__') ||           // Bold
            previewContent.includes('- ') ||           // Lists
            previewContent.includes('* ') ||           // Lists
            previewContent.includes('1. ') ||          // Numbered lists
            previewContent.includes('```') ||          // Code blocks
            previewContent.includes('[') && previewContent.includes('](') // Links
        );
        
        const isMarkdown = isMarkdownByType || (mimeType === 'text/plain' && hasMarkdownContent);
        
        if (mimeType?.startsWith('image/')) {
            // Image preview
            const imageSrc = isBase64Encoded 
                ? `data:${mimeType};base64,${previewContent}`
                : previewContent;
            
            return (
                <img 
                    src={imageSrc}
                    alt={document.name}
                    className={styles.image_preview}
                />
            );
        } else if (fileExtension === 'pdf' || mimeType === 'application/pdf') {
            // PDF preview
            const pdfSrc = isBase64Encoded 
                ? `data:application/pdf;base64,${previewContent}`
                : previewContent;
                
            return (
                <iframe
                    src={pdfSrc}
                    className={styles.pdf_preview}
                    title={document.name}
                />
            );
        } else if (isMarkdown) {
            // Markdown preview
            console.log('Rendering markdown with ReactMarkdown:', previewContent?.substring(0, 200));
            
            return (
                <div className={styles.markdown_preview}>
                    <ReactMarkdown>{previewContent}</ReactMarkdown>
                </div>
            );
        } else if (fileExtension === 'py') {
            // Python code preview
            return (
                <div className={styles.python_code_preview}>
                    <div className={styles.code_header}>
                        <span className={styles.code_language}>Python</span>
                        <span className={styles.code_filename}>
                            {document.ext ? `${document.name}.${document.ext}` : document.name}
                        </span>
                    </div>
                    <pre className={styles.python_code_content}>
                        <code>{previewContent}</code>
                    </pre>
                </div>
            );
        } else if (mimeType?.startsWith('text/') || fileExtension === 'txt') {
            // Enhanced text preview for all text files
            return (
                <div className={styles.enhanced_text_preview}>
                    {previewContent?.split('\n').map((line, index) => {
                        // Handle empty lines
                        if (line.trim() === '') {
                            return <div key={index} className={styles.text_line_break}></div>;
                        }
                        
                        // Check if line looks like a header (all caps, starts with numbers, etc.)
                        const isHeader = line.match(/^[A-Z\s\d\.\-_]+:?\s*$/) && line.length < 80;
                        const isNumberedItem = line.match(/^\s*\d+\.\s/);
                        const isBulletItem = line.match(/^\s*[-*•]\s/);
                        const isIndented = line.match(/^\s{4,}/);
                        
                        return (
                            <div 
                                key={index} 
                                className={`${styles.text_line} ${
                                    isHeader ? styles.text_header :
                                    isNumberedItem ? styles.text_numbered :
                                    isBulletItem ? styles.text_bullet :
                                    isIndented ? styles.text_indented : ''
                                }`}
                            >
                                {line}
                            </div>
                        );
                    })}
                </div>
            );
        } else {
            // Code/raw text preview for non-text files
            return (
                <pre className={styles.code_preview}>
                    {previewContent}
                </pre>
            );
        }
    };

    if (!isOpen) return null;

    return (
        <div className={styles.overlay} onClick={handleBackdropClick}>
            <div className={styles.popup}>
                <div className={styles.header}>
                    <h3 className={styles.title}>
                        {document.ext ? `${document.name}.${document.ext}` : document.name}
                    </h3>
                    <button 
                        className={styles.close_button}
                        onClick={onClose}
                        title="Close preview"
                    >
                        <MdClose />
                    </button>
                </div>
                <div className={styles.content}>
                    {getPreviewComponent()}
                </div>
            </div>
        </div>
    );
};

export default FilePreviewPopup;