RustChain: A Simple Blockchain Implementation

RustChain is a comprehensive blockchain implementation written in Rust, contained within a single main.rs file. It features a fully functional blockchain with block creation, transaction management, proof-of-work consensus, and a simulated peer-to-peer (P2P) network. Key components include:

• Transaction Management: Supports creating and validating transactions with sender/receiver addresses, amounts, timestamps, and simple signatures. Includes balance checks, transaction fees, and double-spend prevention.
• Block Structure: Blocks store transactions, a Merkle root for efficient verification, a nonce for proof-of-work, and a hash linking to the previous block.
• Proof-of-Work: Implements a mining mechanism requiring block hashes to start with a specified number of zeros, adjustable via a difficulty constant.
• Merkle Tree: Calculates a Merkle root for each block to ensure transaction integrity and enable efficient verification.
• Wallet System: Manages user wallets with balance tracking and a limit on the number of wallets.
• P2P Simulation: Simulates a network of nodes that broadcast blocks and resolve chain conflicts by adopting the longest valid chain.
• Logging System: Records blockchain events (e.g., transaction additions, block mining, network broadcasts) with timestamps for debugging and monitoring.
• Utility Functions: Provides extensive querying capabilities, including blockchain age, average transaction amount, total mined coins, and network hash rate.

The code is designed for clarity and extensibility, using only composition (no inheritance or traits) and includes detailed comments for maintainability. It leverages Rust's safety features and concurrency with Arc and Mutex for thread-safe blockchain access. Dependencies include sha2, serde, serde_json, rand, and hex. RustChain serves as an educational tool for understanding blockchain concepts and can be extended with additional features like cryptographic signatures or a real P2P network.