/**
* ContentProcessor - Handles content formatting, escaping, and processing utilities
*/
export class ContentProcessor {
/**
* Escape HTML for safe display
*/
static escapeHtml(text: string): string {
const div = document.createElement('div');
div.textContent = text;
return div.innerHTML;
}
/**
* Unescape HTML entities
*/
static unescapeHtml(html: string): string {
const doc = new DOMParser().parseFromString(html, 'text/html');
return doc.body.textContent || '';
}
/**
* Process markdown content for display (basic implementation)
*/
static processMarkdown(content: string): string {
// Simple markdown processing - can be enhanced later
let processed = content;
// Code blocks
processed = processed.replace(/```(\w*)\n([\s\S]*?)```/g, '<pre><code class="language-$1">$2</code></pre>');
// Inline code
processed = processed.replace(/`([^`]+)`/g, '<code>$1</code>');
// Bold
processed = processed.replace(/\*\*([^*]+)\*\*/g, '<strong>$1</strong>');
// Italic
processed = processed.replace(/\*([^*]+)\*/g, '<em>$1</em>');
// Headers
processed = processed.replace(/^### (.*$)/gim, '<h3>$1</h3>');
processed = processed.replace(/^## (.*$)/gim, '<h2>$1</h2>');
processed = processed.replace(/^# (.*$)/gim, '<h1>$1</h1>');
// Lists
processed = processed.replace(/^[\s]*\* (.+)$/gm, '<li>$1</li>');
processed = processed.replace(/^[\s]*- (.+)$/gm, '<li>$1</li>');
// Wrap consecutive list items in ul tags
processed = processed.replace(/(<li>.*<\/li>)/g, '<ul>$1</ul>');
// Line breaks
processed = processed.replace(/\n/g, '<br>');
return processed;
}
/**
* Sanitize content to prevent XSS
*/
static sanitizeContent(content: string): string {
// Remove potentially dangerous tags and attributes
const dangerous = /<script\b[^<]*(?:(?!<\/script>)<[^<]*)*<\/script>/gi;
let sanitized = content.replace(dangerous, '');
// Remove javascript: and data: URLs
sanitized = sanitized.replace(/javascript:/gi, '');
sanitized = sanitized.replace(/data:/gi, '');
// Remove on* event handlers
sanitized = sanitized.replace(/on\w+\s*=/gi, '');
return sanitized;
}
/**
* Truncate text to specified length with ellipsis
*/
static truncateText(text: string, maxLength: number, ellipsis: string = '...'): string {
if (text.length <= maxLength) {
return text;
}
return text.substring(0, maxLength - ellipsis.length) + ellipsis;
}
/**
* Extract plain text from HTML content
*/
static extractPlainText(html: string): string {
const doc = new DOMParser().parseFromString(html, 'text/html');
return doc.body.textContent || '';
}
/**
* Format conversation preview text
*/
static formatConversationPreview(lastMessage: string, maxLength: number = 100): string {
// Remove markdown formatting for preview
let preview = lastMessage
.replace(/```[\s\S]*?```/g, '[code block]') // Replace code blocks
.replace(/`([^`]+)`/g, '$1') // Remove inline code backticks
.replace(/\*\*([^*]+)\*\*/g, '$1') // Remove bold
.replace(/\*([^*]+)\*/g, '$1') // Remove italic
.replace(/^#+\s*/gm, '') // Remove headers
.replace(/^\s*[-*]\s*/gm, '') // Remove list markers
.replace(/\n+/g, ' ') // Replace newlines with spaces
.trim();
return this.truncateText(preview, maxLength);
}
/**
* Validate and clean message content
*/
static cleanMessageContent(content: string): string {
// Trim whitespace
let cleaned = content.trim();
// Remove excessive whitespace
cleaned = cleaned.replace(/\s+/g, ' ');
// Remove null bytes
cleaned = cleaned.replace(/\0/g, '');
return cleaned;
}
/**
* Check if content is safe for display
*/
static isContentSafe(content: string): boolean {
// Check for dangerous patterns
const dangerousPatterns = [
/<script/i,
/javascript:/i,
/data:text\/html/i,
/vbscript:/i,
/on\w+\s*=/i
];
return !dangerousPatterns.some(pattern => pattern.test(content));
}
/**
* Format file size for display
*/
static formatFileSize(bytes: number): string {
if (bytes === 0) return '0 B';
const k = 1024;
const sizes = ['B', 'KB', 'MB', 'GB'];
const i = Math.floor(Math.log(bytes) / Math.log(k));
return parseFloat((bytes / Math.pow(k, i)).toFixed(1)) + ' ' + sizes[i];
}
}
