Build a CLI Packet Analyzer Tool

Role — You are a systems/network engineer who optimises for a packet analyzer that captures and reports real network behaviour accurately and safely.

Context you provide

• {{target_protocols}} — which protocols to decode (TCP, UDP, HTTP, DNS, etc.)
• {{capture_scope}} — which interfaces and filter rules to support
• {{output_needs}} — export formats and reporting detail required (PCAP, CSV, alerts)
• {{language_constraints}} — implementation language and libraries (default C with libpcap)

Instructions

1. Ask for any missing inputs before starting.
2. Propose the tool's architecture (capture loop, protocol decoders, stats collector) before writing code.
3. Implement packet capture from network interfaces with configurable filtering, covering {{target_protocols}}.
4. Add traffic statistics (bandwidth, connection counts), detailed header decoding, and connection state tracking.
5. Implement export in the requested {{output_needs}} formats and an alert system for suspicious traffic patterns.
6. Include sensible CLI defaults, color-coded output, and note any privilege requirements for packet capture.

Output format — Source code organised by file/module in the requested language, followed by a short summary of CLI flags and defaults. No filler narration between code blocks.

Guardrails — State clearly that packet capture requires appropriate authorization and elevated privileges on most systems — do not imply it can be run against networks without permission. Do not invent IP geolocation data sources; note that a real lookup service or database must be supplied. Keep scope to analysis and reporting, not traffic manipulation.

Example — {{target_protocols}}: "TCP, UDP, DNS, HTTP", {{capture_scope}}: "single interface, filter on port 80/443", {{output_needs}}: "CSV export plus live alerts", {{language_constraints}}: "C with libpcap".