Token Recycle System

1. System Overview

The token recycle system is a token recycling and destruction management platform implemented in Solidity, supporting recycling, destruction, and reuse of multiple tokens. The system implements flexible recycling strategies and comprehensive destruction mechanisms.

1.1 Main Features

Multi-token recycling: Support for multiple token recycling
Flexible strategies: Support for multiple recycling strategies
Automatic destruction: Automated destruction process
Reuse mechanism: Support for token reuse
Complete records: Comprehensive operation records

2. Contract Implementation

solidity

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.0;

import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/access/Ownable.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";
import "@openzeppelin/contracts/utils/math/SafeMath.sol";

/**
 * @title TokenRecycle
 * @dev Token recycle contract
 */
contract TokenRecycle is Ownable, ReentrancyGuard {
    using SafeMath for uint256;

    // Strategy information
    struct Strategy {
        IERC20 token;              // Recycling token
        uint256 minAmount;         // Minimum recycling amount
        uint256 maxAmount;         // Maximum recycling amount
        uint256 totalRecycled;     // Total recycled amount
        uint256 lastUpdateTime;    // Last update time
        bool isActive;             // Whether active
        bool isReusable;           // Whether reusable
    }

    // Recycle record
    struct RecycleRecord {
        address user;              // User address
        uint256 amount;            // Recycled amount
        uint256 timestamp;         // Recycle time
        bool isDestroyed;          // Whether destroyed
    }

    // State variables
    mapping(uint256 => Strategy) public strategies;            // Recycling strategies
    mapping(uint256 => RecycleRecord[]) public recycleRecords; // Recycle records
    uint256 public strategyCount;                             // Strategy count
    bool public paused;                                       // Pause status

    // Events
    event StrategyCreated(uint256 indexed strategyId, address token);
    event TokenRecycled(uint256 indexed strategyId, address indexed user, uint256 amount);
    event TokenDestroyed(uint256 indexed strategyId, uint256 amount);
    event TokenReused(uint256 indexed strategyId, address indexed to, uint256 amount);
    event StrategyStatusChanged(uint256 indexed strategyId, bool isActive);

    /**
     * @dev Constructor
     */
    constructor() {
        // Initialize state
    }

    /**
     * @dev Create recycling strategy
     */
    function createStrategy(
        IERC20 _token,
        uint256 _minAmount,
        uint256 _maxAmount,
        bool _isReusable
    ) external onlyOwner {
        require(address(_token) != address(0), "Invalid token");
        require(_maxAmount >= _minAmount, "Invalid amounts");

        strategies[strategyCount] = Strategy({
            token: _token,
            minAmount: _minAmount,
            maxAmount: _maxAmount,
            totalRecycled: 0,
            lastUpdateTime: block.timestamp,
            isActive: true,
            isReusable: _isReusable
        });

        emit StrategyCreated(strategyCount, address(_token));
        strategyCount = strategyCount.add(1);
    }

    /**
     * @dev Recycle tokens
     */
    function recycleTokens(uint256 strategyId, uint256 amount) external nonReentrant {
        require(!paused, "System paused");
        require(strategyId < strategyCount, "Invalid strategy ID");
        
        Strategy storage strategy = strategies[strategyId];
        require(strategy.isActive, "Strategy not active");
        require(amount >= strategy.minAmount, "Amount too small");
        require(amount <= strategy.maxAmount, "Amount too large");

        // Transfer tokens
        strategy.token.transferFrom(msg.sender, address(this), amount);
        
        // Update state
        strategy.totalRecycled = strategy.totalRecycled.add(amount);
        strategy.lastUpdateTime = block.timestamp;

        // Record recycling
        recycleRecords[strategyId].push(RecycleRecord({
            user: msg.sender,
            amount: amount,
            timestamp: block.timestamp,
            isDestroyed: false
        }));

        emit TokenRecycled(strategyId, msg.sender, amount);
    }

    /**
     * @dev Destroy tokens
     */
    function destroyTokens(uint256 strategyId) external onlyOwner {
        require(strategyId < strategyCount, "Invalid strategy ID");
        Strategy storage strategy = strategies[strategyId];
        require(!strategy.isReusable, "Tokens are reusable");

        uint256 balance = strategy.token.balanceOf(address(this));
        require(balance > 0, "No tokens to destroy");

        // Destroy tokens (transfer to zero address)
        strategy.token.transfer(address(0), balance);

        // Update records
        RecycleRecord[] storage records = recycleRecords[strategyId];
        for (uint256 i = 0; i < records.length; i++) {
            if (!records[i].isDestroyed) {
                records[i].isDestroyed = true;
            }
        }

        emit TokenDestroyed(strategyId, balance);
    }

    /**
     * @dev Reuse tokens
     */
    function reuseTokens(
        uint256 strategyId,
        address to,
        uint256 amount
    ) external onlyOwner {
        require(strategyId < strategyCount, "Invalid strategy ID");
        Strategy storage strategy = strategies[strategyId];
        require(strategy.isReusable, "Tokens not reusable");
        require(to != address(0), "Invalid address");

        uint256 balance = strategy.token.balanceOf(address(this));
        require(balance >= amount, "Insufficient balance");

        // Transfer tokens
        strategy.token.transfer(to, amount);

        emit TokenReused(strategyId, to, amount);
    }

    /**
     * @dev Set strategy status
     */
    function setStrategyStatus(uint256 strategyId, bool isActive) external onlyOwner {
        require(strategyId < strategyCount, "Invalid strategy ID");
        strategies[strategyId].isActive = isActive;
        emit StrategyStatusChanged(strategyId, isActive);
    }

    /**
     * @dev Update strategy parameters
     */
    function updateStrategy(
        uint256 strategyId,
        uint256 minAmount,
        uint256 maxAmount,
        bool isReusable
    ) external onlyOwner {
        require(strategyId < strategyCount, "Invalid strategy ID");
        require(maxAmount >= minAmount, "Invalid amounts");

        Strategy storage strategy = strategies[strategyId];
        strategy.minAmount = minAmount;
        strategy.maxAmount = maxAmount;
        strategy.isReusable = isReusable;
    }

    /**
     * @dev Pause/unpause system
     */
    function setPaused(bool _paused) external onlyOwner {
        paused = _paused;
    }

    /**
     * @dev Get strategy information
     */
    function getStrategyInfo(uint256 strategyId) external view returns (
        address token,
        uint256 minAmount,
        uint256 maxAmount,
        uint256 totalRecycled,
        uint256 lastUpdateTime,
        bool isActive,
        bool isReusable
    ) {
        require(strategyId < strategyCount, "Invalid strategy ID");
        Strategy storage strategy = strategies[strategyId];
        return (
            address(strategy.token),
            strategy.minAmount,
            strategy.maxAmount,
            strategy.totalRecycled,
            strategy.lastUpdateTime,
            strategy.isActive,
            strategy.isReusable
        );
    }

    /**
     * @dev Get recycle record count
     */
    function getRecycleRecordCount(uint256 strategyId) external view returns (uint256) {
        return recycleRecords[strategyId].length;
    }

    /**
     * @dev Get recycle record
     */
    function getRecycleRecord(uint256 strategyId, uint256 index) external view returns (
        address user,
        uint256 amount,
        uint256 timestamp,
        bool isDestroyed
    ) {
        require(strategyId < strategyCount, "Invalid strategy ID");
        require(index < recycleRecords[strategyId].length, "Invalid index");

        RecycleRecord storage record = recycleRecords[strategyId][index];
        return (
            record.user,
            record.amount,
            record.timestamp,
            record.isDestroyed
        );
    }
}

3. Function Description

3.1 Recycling Strategy Management

Create strategy
Update strategy
Strategy status management

3.2 Token Recycling

Token recycling
Token destruction
Token reuse

3.3 Status Query

Strategy information query
Recycling record query
Status statistics

4. Security Mechanism

4.1 Recycling Control

Quantity limit
Strategy control
Pause mechanism

4.2 Access Control

Permission management
Reentrancy protection
Parameter verification

4.3 Status Management

Strategy status
Record maintenance
Destruction confirmation

5. Usage Example

5.1 Create Recycling Strategy

javascript

await tokenRecycle.createStrategy(
    token.address,
    minAmount,
    maxAmount,
    isReusable
);

5.2 Recycle Tokens

javascript

await tokenRecycle.recycleTokens(strategyId, amount);

5.3 Destroy Tokens

javascript

await tokenRecycle.destroyTokens(strategyId);

6. Summary

The token recycle system implements a complete recycling management function, including:

Multi-token recycling support
Flexible strategy management
Automated destruction process
Reuse mechanism
Complete security mechanism

The system ensures the security and reliability of the token recycling process through carefully designed recycling strategies and security mechanisms.

Frequently Asked Questions (FAQ)

1. Basic Concepts

Q: What is token recycling? A: Token recycling is a mechanism for recycling tokens from specified addresses or invalid addresses through smart contracts. This mechanism can:

Recycle tokens from erroneous transfers
Clean up tokens from invalid addresses
Optimize token allocation
Maintain token ecology
Improve token utilization

Q: What is the difference between recycling and destruction? A: The main differences include:

Recycling is reusing tokens
Destruction is permanently reducing supply
Recycling can be redistributed
Recycling does not affect the total supply
Recycling is more flexible

Q: Which tokens can be recycled? A: Recyclable tokens include:

Tokens from erroneous transfers
Tokens from long-term unused addresses
Tokens from expired locked addresses
Tokens from invalid addresses
Tokens from remaining contracts

Q: How are recycled tokens processed? A: Processing methods include:

Redistribution
Entering reserve pools
Used for community incentives
Destruction processing
Liquidity supplementation

Q: How to ensure the security of recycling? A: Security measures include:

solidity

// Permission control
modifier onlyAuthorized() {
    require(hasRole(RECYCLER_ROLE, msg.sender), "Not authorized");
    _;
}

// Multiple verification
function recycle(address target) external onlyAuthorized {
    require(isValidTarget(target), "Invalid target");
    require(getBalance(target) > 0, "No balance");
    require(lastRecycleTime[target] + cooldown < block.timestamp, "Cooldown");
    _executeRecycle(target);
}

Q: How to prevent accidental recycling? A: Protection measures include:

Whitelist protection
Multi-signature
Cooling period setting
Amount threshold
Operation confirmation

Q: How to improve recycling efficiency? A: Optimization strategies:

Batch processing
Intelligent routing
Automatic detection
Priority sorting
Gas optimization

Q: How to reduce recycling costs? A: Cost control:

Merging transactions
Choosing low-Gas periods
Optimizing contract code
Reducing storage operations
Using events instead of storage

5. Implementation Details

Q: How to identify recyclable addresses? A: Identification methods:

solidity

function isRecyclable(address target) internal view returns (bool) {
    return
        !isExcluded(target) &&
        getBalance(target) > minRecycleAmount &&
        lastActivity[target] + inactiveThreshold < block.timestamp;
}

Q: How to handle recycling failures? A: Error handling:

Automatic retries
Failure recording
Manual intervention
Status recovery
Notification mechanism

6. Best Practices

Q: How to develop recycling strategies? A: Strategy considerations:

Recycling condition settings
Processing priority
Time arrangement
Resource allocation
Effect evaluation

Q: How to improve recycling transparency? A: Transparency mechanisms:

Public recycling rules
Real-time status updates
Operation record disclosure
Result timely disclosure
Community supervision

7. Error Handling

Q: Common errors and solutions? A: Error types:

"Invalid address": Verify address validity
"Insufficient balance": Check balance
"Not recyclable": Confirm recycling conditions
"Already recycled": Check status
"System paused": Wait for system recovery

Q: How to handle abnormal situations? A: Handling mechanisms:

Emergency pause
Fund protection
Status rollback
Logging
Administrator notification

8. Upgrade Maintenance

Q: How to upgrade the recycling mechanism? A: Upgrade plans:

Upgradable contracts
Parameter adjustments
Logical updates
Data migration
Compatibility assurance

Q: How to monitor the recycling system? A: Monitoring plans:

Real-time data analysis
Abnormal detection
Performance monitoring
Effect evaluation
Regular audits

9. Integration with Other Modules

Q: How to cooperate with other functions? A: Cooperative strategies:

Unified permission management
Shared data storage
Coordinated execution timing
Consistent interface design
Complete event notifications

Q: How to handle cross-chain recycling? A: Cross-chain solutions:

Bridge protocol docking
Unified recycling standards
Cross-chain message passing
Status synchronization mechanisms
Security assurance

Token Recycle System ​

1. System Overview ​

1.1 Main Features ​

2. Contract Implementation ​

3. Function Description ​

3.1 Recycling Strategy Management ​

3.2 Token Recycling ​

3.3 Status Query ​

4. Security Mechanism ​

4.1 Recycling Control ​

4.2 Access Control ​

4.3 Status Management ​

5. Usage Example ​

5.1 Create Recycling Strategy ​

5.2 Recycle Tokens ​

5.3 Destroy Tokens ​

6. Summary ​

Frequently Asked Questions (FAQ) ​

1. Basic Concepts ​

2. Function Related ​

3. Security Related ​

4. Optimization Related ​

5. Implementation Details ​

6. Best Practices ​

7. Error Handling ​

8. Upgrade Maintenance ​

9. Integration with Other Modules ​

Token Recycle System

1. System Overview

1.1 Main Features

2. Contract Implementation

3. Function Description

3.1 Recycling Strategy Management

3.2 Token Recycling

3.3 Status Query

4. Security Mechanism

4.1 Recycling Control

4.2 Access Control

4.3 Status Management

5. Usage Example

5.1 Create Recycling Strategy

5.2 Recycle Tokens

5.3 Destroy Tokens

6. Summary

Frequently Asked Questions (FAQ)

1. Basic Concepts

2. Function Related

3. Security Related

4. Optimization Related

5. Implementation Details

6. Best Practices

7. Error Handling

8. Upgrade Maintenance

9. Integration with Other Modules