docs: update README.md

Author: OleksandrZadvornyi

README.md

@@ -7,6 +7,7 @@
 - 📦 Publish-ready for NPM usage
 - 🔍 Automatically validates URL accessibility before analysis
 - 📊 Comprehensive progress reporting and analysis summaries
+- 📝 Multiple export formats (HTML, JSON, Markdown)
 
 ## 📦 Installation
 
@@ -50,13 +51,26 @@ frontend-performance-analyzer --input urls.json
 # Save HTML report (automatically named based on URL)
 frontend-performance-analyzer --url https://example.com --output
 
+# Save JSON report to file
+frontend-performance-analyzer --url https://example.com --json-file report.json
+
 # Save Markdown summary (automatically named based on URL)
 frontend-performance-analyzer --url https://example.com --markdown
 
 # Output raw JSON to console
 frontend-performance-analyzer --url https://example.com --json
 ```
 
+### Logging and Verbosity Options
+
+```bash
+# Verbose output with debugging details
+frontend-performance-analyzer --url https://example.com --verbose
+
+# Minimal output (errors and final results only)
+frontend-performance-analyzer --url https://example.com --silent
+```
+
 ### Use Performance Threshold
 
 Exit with failure if score is below threshold:
@@ -70,9 +84,10 @@ frontend-performance-analyzer --url https://example.com --threshold 85
 The tool automatically:
 
 - ✅ Validates URL format before analysis
-- 🔍 Checks URL accessibility with HEAD requests
+- 🔍 Checks URL accessibility with HEAD requests and 10-second timeout
 - ⚠️ Warns about inaccessible URLs and skips them
 - 📊 Provides detailed progress reporting during analysis
+- 🔄 Continues analysis even if some URLs fail
 
 ## 📊 Sample Output
 
@@ -108,15 +123,61 @@ Cumulative Layout Shift: 0.01
 - `.txt`: List of URLs separated by new lines
 - `.json`: JSON array of URLs, e.g. `["https://example.com", "https://github.com"]`
 
-## 🚨 Error Handling
+## 📄 Export Formats
+
+### HTML Reports
+
+- Full Lighthouse HTML report with all details
+- Automatically named based on URL (e.g., `example_com.html`)
+
+### JSON Reports
+
+- Structured JSON output with performance metrics
+- Includes timestamp, tool version, and detailed scores
+- Supports both single URL and batch analysis
+- Contains all Lighthouse categories (Performance, Accessibility, Best Practices, SEO, PWA)
+
+### Markdown Reports
+
+- Human-readable performance summary
+- Core Web Vitals breakdown with visual indicators
+- Performance opportunities and diagnostics
+- Category scores with emoji indicators
+- Automatically named based on URL (e.g., `example_com.md`)
 
-The tool provides comprehensive validation:
+## 🚨 Error Handling & Validation
 
-- **Invalid URLs**: checks URL format before processing
-- **Inaccessible URLs**: tests connectivity and skips unreachable sites
-- **File validation**: ensures input files exist and have correct extensions
+The tool provides comprehensive validation and error handling:
+
+- **Invalid URLs**: validates URL format before processing
+- **Inaccessible URLs**: tests connectivity with HEAD requests and 10-second timeout
+- **File validation**: ensures input files exist and have correct extensions (.txt or .json)
 - **Threshold validation**: validates threshold values are between 0-100
 - **Graceful failures**: continues analysis even if some URLs fail
+- **Lighthouse warnings**: filters internal Lighthouse warnings for cleaner output
+- **Browser management**: proper cleanup of browser instances
+
+## 🔧 Advanced Features
+
+### Logging Levels
+
+- **Normal**: standard output with progress indicators
+- **Verbose** (`--verbose`): detailed debugging information including timing
+- **Silent** (`--silent`): minimal output, errors and final results only
+
+### Performance Monitoring
+
+- Tracks analysis time per URL
+- Reports overall performance (URLs/second)
+- Browser launch and close timing
+- Accessibility check timing
+
+### Batch Processing
+
+- Supports multiple URL analysis in a single run
+- Consolidated JSON export for batch results
+- Individual file exports for each URL
+- Progress tracking with clear indicators
 
 ## 🛠 Development
 
@@ -127,6 +188,20 @@ npm install
 node cli.js --url https://example.com
 ```
 
+### Project Structure
+
+```
+├── cli.js                   # Main CLI entry point
+├── lib/
+│   ├── lighthouse.js        # Lighthouse analysis logic
+│   ├── logger.js            # Logging utilities
+│   └── url-utils.js         # URL validation and processing
+└── report-formatters/
+    ├── console.js           # Console output formatting
+    ├── json.js              # JSON export functionality
+    └── markdown.js          # Markdown report generation
+```
+
 ## 📄 License
 
 MIT © 2025 Oleksandr Zadvornyi