tool-compression-mcp/dist/compressors/read.js

/**
 * Read Compressor - Compress file content while preserving essential information
 *
 * Strategies:
 * - Remove blank lines (configurable)
 * - Remove comment-only lines (language-aware)
 * - Collapse import blocks
 * - Preserve line numbers for reference
 */
// Language-specific comment patterns
const COMMENT_PATTERNS = {
    // Single-line comments
    javascript: [/^\s*\/\/.*$/, /^\s*\/\*.*\*\/\s*$/],
    typescript: [/^\s*\/\/.*$/, /^\s*\/\*.*\*\/\s*$/],
    python: [/^\s*#.*$/],
    ruby: [/^\s*#.*$/],
    bash: [/^\s*#.*$/],
    swift: [/^\s*\/\/.*$/],
    go: [/^\s*\/\/.*$/],
    rust: [/^\s*\/\/.*$/],
    php: [/^\s*\/\/.*$/, /^\s*#.*$/, /^\s*\/\*.*\*\/\s*$/],
};
// Import patterns by language
const IMPORT_PATTERNS = {
    javascript: /^(import|export)\s+/,
    typescript: /^(import|export)\s+/,
    python: /^(import|from)\s+/,
    swift: /^import\s+/,
    go: /^import\s+/,
    rust: /^use\s+/,
    php: /^(use|require|include)/,
};
function detectLanguage(filename) {
    const ext = filename.split('.').pop()?.toLowerCase() || '';
    const langMap = {
        js: 'javascript',
        jsx: 'javascript',
        ts: 'typescript',
        tsx: 'typescript',
        py: 'python',
        rb: 'ruby',
        sh: 'bash',
        bash: 'bash',
        swift: 'swift',
        go: 'go',
        rs: 'rust',
        php: 'php',
    };
    return langMap[ext] || 'unknown';
}
function isCommentLine(line, language) {
    const patterns = COMMENT_PATTERNS[language];
    if (!patterns)
        return false;
    return patterns.some(pattern => pattern.test(line));
}
function isImportLine(line, language) {
    const pattern = IMPORT_PATTERNS[language];
    if (!pattern)
        return false;
    return pattern.test(line.trim());
}
export function compressRead(content, filename, options = {}) {
    const { removeBlankLines = true, removeComments = true, collapseImports = true, maxLines = 500, } = options;
    const language = detectLanguage(filename);
    const lines = content.split('\n');
    const originalLines = lines.length;
    const result = [];
    let importBlock = [];
    let inImportBlock = false;
    let lineNumber = 0;
    for (const line of lines) {
        lineNumber++;
        // Skip blank lines if configured
        if (removeBlankLines && line.trim() === '') {
            continue;
        }
        // Skip comment lines if configured
        if (removeComments && isCommentLine(line, language)) {
            continue;
        }
        // Handle import collapsing
        if (collapseImports && isImportLine(line, language)) {
            if (!inImportBlock) {
                inImportBlock = true;
                importBlock = [];
            }
            importBlock.push(line.trim());
            continue;
        }
        else if (inImportBlock) {
            // End of import block - collapse it
            if (importBlock.length > 3) {
                result.push(`// [${importBlock.length} imports collapsed]`);
            }
            else {
                result.push(...importBlock);
            }
            importBlock = [];
            inImportBlock = false;
        }
        // Add line with number prefix for reference
        result.push(`${lineNumber}: ${line}`);
    }
    // Handle remaining imports at end of file
    if (importBlock.length > 0) {
        if (importBlock.length > 3) {
            result.push(`// [${importBlock.length} imports collapsed]`);
        }
        else {
            result.push(...importBlock);
        }
    }
    // Truncate if too long
    let compressed = result;
    let truncated = false;
    if (compressed.length > maxLines) {
        compressed = compressed.slice(0, maxLines);
        compressed.push(`\n... [${result.length - maxLines} more lines truncated]`);
        truncated = true;
    }
    const compressedLines = compressed.length;
    const savings = ((1 - compressedLines / originalLines) * 100).toFixed(1);
    return {
        content: compressed.join('\n'),
        originalLines,
        compressedLines,
        savings: `${savings}%`,
    };
}