Carbon Credit Tokenization: How to Farm Environmental Yields Like a Green DeFi Degen

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.19;

import "@openzeppelin/contracts/token/ERC20/ERC20.sol";
import "@openzeppelin/contracts/access/AccessControl.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";

contract CarbonCreditToken is ERC20, AccessControl, ReentrancyGuard {
    bytes32 public constant VERIFIER_ROLE = keccak256("VERIFIER_ROLE");
    bytes32 public constant PROJECT_ROLE = keccak256("PROJECT_ROLE");
    
    struct CreditMetadata {
        string projectId;           // Unique project identifier
        string methodology;         // Verification standard (VCS, Gold Standard)
        uint256 vintage;           // Year of carbon reduction
        string location;           // Geographic coordinates
        bool isRetired;           // Whether credit is permanently retired
        uint256 retirementDate;   // Timestamp of retirement
    }
    
    mapping(uint256 => CreditMetadata) public creditData;
    mapping(address => uint256[]) public userCredits;
    
    uint256 private _nextCreditId = 1;
    uint256 public totalRetired;
    
    event CreditMinted(
        uint256 indexed creditId,
        address indexed recipient,
        uint256 amount,
        string projectId
    );
    
    event CreditRetired(
        uint256 indexed creditId,
        address indexed retiree,
        uint256 amount,
        string reason
    );
    
    constructor() ERC20("Carbon Credit Token", "CCT") {
        _grantRole(DEFAULT_ADMIN_ROLE, msg.sender);
        _grantRole(VERIFIER_ROLE, msg.sender);
    }
    
    // Mint verified carbon credits to environmental projects
    function mintCarbonCredit(
        address recipient,
        uint256 amount,
        string memory projectId,
        string memory methodology,
        uint256 vintage,
        string memory location
    ) external onlyRole(VERIFIER_ROLE) {
        require(amount > 0, "Amount must be positive");
        require(vintage <= block.timestamp, "Future vintage not allowed");
        
        uint256 creditId = _nextCreditId++;
        
        creditData[creditId] = CreditMetadata({
            projectId: projectId,
            methodology: methodology,
            vintage: vintage,
            location: location,
            isRetired: false,
            retirementDate: 0
        });
        
        userCredits[recipient].push(creditId);
        _mint(recipient, amount);
        
        emit CreditMinted(creditId, recipient, amount, projectId);
    }
    
    // Permanently retire carbon credits to claim environmental benefit
    function retireCredits(
        uint256 creditId,
        uint256 amount,
        string memory reason
    ) external nonReentrant {
        require(amount > 0, "Amount must be positive");
        require(balanceOf(msg.sender) >= amount, "Insufficient balance");
        require(!creditData[creditId].isRetired, "Credits already retired");
        
        creditData[creditId].isRetired = true;
        creditData[creditId].retirementDate = block.timestamp;
        
        totalRetired += amount;
        _burn(msg.sender, amount);
        
        emit CreditRetired(creditId, msg.sender, amount, reason);
    }
    
    // Get credit metadata for transparency
    function getCreditInfo(uint256 creditId) 
        external view returns (CreditMetadata memory) {
        return creditData[creditId];
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.19;

import "./CarbonCreditToken.sol";
import "@openzeppelin/contracts/token/ERC20/IERC20.sol";
import "@openzeppelin/contracts/security/ReentrancyGuard.sol";

contract EnvironmentalYieldFarm is ReentrancyGuard {
    CarbonCreditToken public carbonToken;
    IERC20 public rewardToken;
    
    struct PoolInfo {
        uint256 totalStaked;        // Total carbon credits staked
        uint256 rewardPerToken;     // Accumulated rewards per token
        uint256 lastUpdateTime;     // Last reward calculation time
        uint256 rewardRate;         // Rewards per second
        uint256 impactMultiplier;   // Bonus for high-impact projects
    }
    
    struct UserInfo {
        uint256 stakedAmount;       // User's staked carbon credits
        uint256 rewardDebt;         // Rewards already paid out
        uint256 pendingRewards;     // Unclaimed rewards
        uint256 stakingTime;        // When user started staking
    }
    
    mapping(string => PoolInfo) public pools;     // projectId => pool info
    mapping(address => mapping(string => UserInfo)) public userInfo;
    
    string[] public activeProjects;
    uint256 public constant REWARD_PRECISION = 1e18;
    uint256 public constant MIN_STAKE_PERIOD = 30 days;
    
    event Staked(address indexed user, string projectId, uint256 amount);
    event Unstaked(address indexed user, string projectId, uint256 amount);
    event RewardsClaimed(address indexed user, string projectId, uint256 amount);
    
    constructor(address _carbonToken, address _rewardToken) {
        carbonToken = CarbonCreditToken(_carbonToken);
        rewardToken = IERC20(_rewardToken);
    }
    
    // Add new project pool for yield farming
    function addProject(
        string memory projectId,
        uint256 rewardRate,
        uint256 impactMultiplier
    ) external {
        require(pools[projectId].lastUpdateTime == 0, "Project already exists");
        
        pools[projectId] = PoolInfo({
            totalStaked: 0,
            rewardPerToken: 0,
            lastUpdateTime: block.timestamp,
            rewardRate: rewardRate,
            impactMultiplier: impactMultiplier
        });
        
        activeProjects.push(projectId);
    }
    
    // Stake carbon credits to earn environmental yields
    function stake(string memory projectId, uint256 amount) 
        external nonReentrant {
        require(amount > 0, "Amount must be positive");
        require(
            carbonToken.balanceOf(msg.sender) >= amount,
            "Insufficient carbon credits"
        );
        
        updateRewards(projectId);
        
        PoolInfo storage pool = pools[projectId];
        UserInfo storage user = userInfo[msg.sender][projectId];
        
        // Transfer carbon credits to farm contract
        carbonToken.transferFrom(msg.sender, address(this), amount);
        
        // Calculate pending rewards before updating stake
        if (user.stakedAmount > 0) {
            uint256 pending = calculateRewards(msg.sender, projectId);
            user.pendingRewards += pending;
        }
        
        // Update user and pool state
        user.stakedAmount += amount;
        user.rewardDebt = (user.stakedAmount * pool.rewardPerToken) / REWARD_PRECISION;
        user.stakingTime = block.timestamp;
        
        pool.totalStaked += amount;
        
        emit Staked(msg.sender, projectId, amount);
    }
    
    // Unstake carbon credits and claim rewards
    function unstake(string memory projectId, uint256 amount) 
        external nonReentrant {
        UserInfo storage user = userInfo[msg.sender][projectId];
        require(user.stakedAmount >= amount, "Insufficient staked amount");
        require(
            block.timestamp >= user.stakingTime + MIN_STAKE_PERIOD,
            "Minimum stake period not met"
        );
        
        updateRewards(projectId);
        claimRewards(projectId);
        
        PoolInfo storage pool = pools[projectId];
        
        // Update user and pool state
        user.stakedAmount -= amount;
        user.rewardDebt = (user.stakedAmount * pool.rewardPerToken) / REWARD_PRECISION;
        
        pool.totalStaked -= amount;
        
        // Transfer carbon credits back to user
        carbonToken.transfer(msg.sender, amount);
        
        emit Unstaked(msg.sender, projectId, amount);
    }
    
    // Claim accumulated yield farming rewards
    function claimRewards(string memory projectId) public nonReentrant {
        updateRewards(projectId);
        
        UserInfo storage user = userInfo[msg.sender][projectId];
        uint256 pending = calculateRewards(msg.sender, projectId);
        uint256 totalRewards = user.pendingRewards + pending;
        
        if (totalRewards > 0) {
            user.pendingRewards = 0;
            user.rewardDebt = (user.stakedAmount * pools[projectId].rewardPerToken) / REWARD_PRECISION;
            
            rewardToken.transfer(msg.sender, totalRewards);
            emit RewardsClaimed(msg.sender, projectId, totalRewards);
        }
    }
    
    // Update reward calculations for pool
    function updateRewards(string memory projectId) internal {
        PoolInfo storage pool = pools[projectId];
        
        if (block.timestamp <= pool.lastUpdateTime) {
            return;
        }
        
        if (pool.totalStaked == 0) {
            pool.lastUpdateTime = block.timestamp;
            return;
        }
        
        uint256 timeElapsed = block.timestamp - pool.lastUpdateTime;
        uint256 reward = timeElapsed * pool.rewardRate * pool.impactMultiplier;
        
        pool.rewardPerToken += (reward * REWARD_PRECISION) / pool.totalStaked;
        pool.lastUpdateTime = block.timestamp;
    }
    
    // Calculate pending rewards for user
    function calculateRewards(address userAddr, string memory projectId) 
        internal view returns (uint256) {
        UserInfo storage user = userInfo[userAddr][projectId];
        PoolInfo storage pool = pools[projectId];
        
        uint256 accRewardPerToken = pool.rewardPerToken;
        
        if (block.timestamp > pool.lastUpdateTime && pool.totalStaked > 0) {
            uint256 timeElapsed = block.timestamp - pool.lastUpdateTime;
            uint256 reward = timeElapsed * pool.rewardRate * pool.impactMultiplier;
            accRewardPerToken += (reward * REWARD_PRECISION) / pool.totalStaked;
        }
        
        return ((user.stakedAmount * accRewardPerToken) / REWARD_PRECISION) - user.rewardDebt;
    }
    
    // Get user's pending rewards
    function getPendingRewards(address userAddr, string memory projectId) 
        external view returns (uint256) {
        UserInfo storage user = userInfo[userAddr][projectId];
        return user.pendingRewards + calculateRewards(userAddr, projectId);
    }
}

// SPDX-License-Identifier: MIT
pragma solidity ^0.8.19;

import "@chainlink/contracts/src/v0.8/interfaces/AggregatorV3Interface.sol";
import "./CarbonCreditToken.sol";

contract CarbonVerificationOracle {
    CarbonCreditToken public carbonToken;
    
    struct VerificationStandard {
        string name;                // VCS, Gold Standard, CAR, etc.
        uint256 qualityScore;       // 1-100 quality rating
        bool isActive;             // Whether standard is accepted
        uint256 verificationFee;   // Cost in wei to verify
    }
    
    struct ProjectVerification {
        string externalId;          // ID in external registry
        string standard;           // Verification standard used
        uint256 verifiedAmount;    // Total verified carbon reductions
        uint256 lastUpdate;       // Last verification timestamp
        bool isValid;             // Current validity status
        string methodology;       // Specific methodology used
    }
    
    mapping(string => VerificationStandard) public standards;
    mapping(string => ProjectVerification) public projectVerifications;
    mapping(address => bool) public authorizedOracles;
    
    event ProjectVerified(
        string indexed projectId,
        string standard,
        uint256 amount,
        uint256 timestamp
    );
    
    event VerificationRevoked(
        string indexed projectId,
        string reason,
        uint256 timestamp
    );
    
    constructor(address _carbonToken) {
        carbonToken = CarbonCreditToken(_carbonToken);
        
        // Initialize major verification standards
        standards["VCS"] = VerificationStandard({
            name: "Verified Carbon Standard",
            qualityScore: 95,
            isActive: true,
            verificationFee: 0.01 ether
        });
        
        standards["GS"] = VerificationStandard({
            name: "Gold Standard",
            qualityScore: 98,
            isActive: true,
            verificationFee: 0.015 ether
        });
        
        standards["CAR"] = VerificationStandard({
            name: "Climate Action Reserve",
            qualityScore: 92,
            isActive: true,
            verificationFee: 0.008 ether
        });
    }
    
    // Verify project against external carbon registry
    function verifyProject(
        string memory projectId,
        string memory externalId,
        string memory standard,
        uint256 verifiedAmount,
        string memory methodology
    ) external payable {
        require(authorizedOracles[msg.sender], "Unauthorized oracle");
        require(standards[standard].isActive, "Invalid verification standard");
        require(
            msg.value >= standards[standard].verificationFee,
            "Insufficient verification fee"
        );
        
        projectVerifications[projectId] = ProjectVerification({
            externalId: externalId,
            standard: standard,
            verifiedAmount: verifiedAmount,
            lastUpdate: block.timestamp,
            isValid: true,
            methodology: methodology
        });
        
        emit ProjectVerified(projectId, standard, verifiedAmount, block.timestamp);
    }
    
    // Check if project meets verification requirements
    function isProjectVerified(string memory projectId) 
        external view returns (bool) {
        ProjectVerification memory verification = projectVerifications[projectId];
        
        // Project must be verified within last 365 days
        return verification.isValid && 
               (block.timestamp - verification.lastUpdate) <= 365 days;
    }
    
    // Get project quality score based on verification standard
    function getProjectQualityScore(string memory projectId) 
        external view returns (uint256) {
        ProjectVerification memory verification = projectVerifications[projectId];
        
        if (!verification.isValid) {
            return 0;
        }
        
        return standards[verification.standard].qualityScore;
    }
    
    // Revoke verification for non-compliant projects
    function revokeVerification(string memory projectId, string memory reason) 
        external {
        require(authorizedOracles[msg.sender], "Unauthorized oracle");
        
        projectVerifications[projectId].isValid = false;
        
        emit VerificationRevoked(projectId, reason, block.timestamp);
    }
    
    // Add new verification standard
    function addVerificationStandard(
        string memory standardId,
        string memory name,
        uint256 qualityScore,
        uint256 verificationFee
    ) external {
        require(authorizedOracles[msg.sender], "Unauthorized oracle");
        require(qualityScore <= 100, "Quality score must be <= 100");
        
        standards[standardId] = VerificationStandard({
            name: name,
            qualityScore: qualityScore,
            isActive: true,
            verificationFee: verificationFee
        });
    }
}

// CarbonCreditAMM.ts - Automated Market Maker for Carbon Credits

import { ethers } from 'ethers';

interface CarbonPool {
  projectId: string;
  carbonReserve: bigint;
  stableReserve: bigint;
  totalShares: bigint;
  lastPrice: bigint;
  volume24h: bigint;
}

class CarbonCreditAMM {
  private pools: Map<string, CarbonPool> = new Map();
  private provider: ethers.Provider;
  private contract: ethers.Contract;
  
  constructor(provider: ethers.Provider, contractAddress: string, abi: any[]) {
    this.provider = provider;
    this.contract = new ethers.Contract(contractAddress, abi, provider);
  }
  
  // Add liquidity to carbon credit pool
  async addLiquidity(
    projectId: string,
    carbonAmount: bigint,
    stableAmount: bigint,
    signer: ethers.Signer
  ): Promise<bigint> {
    const pool = this.pools.get(projectId);
    
    if (!pool) {
      // Initialize new pool
      const shares = this.sqrt(carbonAmount * stableAmount);
      
      this.pools.set(projectId, {
        projectId,
        carbonReserve: carbonAmount,
        stableReserve: stableAmount,
        totalShares: shares,
        lastPrice: (stableAmount * BigInt(1e18)) / carbonAmount,
        volume24h: BigInt(0)
      });
      
      return shares;
    }
    
    // Calculate optimal liquidity amounts
    const carbonQuote = (stableAmount * pool.carbonReserve) / pool.stableReserve;
    const stableQuote = (carbonAmount * pool.stableReserve) / pool.carbonReserve;
    
    const finalCarbon = carbonAmount < carbonQuote ? carbonAmount : carbonQuote;
    const finalStable = stableAmount < stableQuote ? stableAmount : stableQuote;
    
    // Calculate shares to mint
    const shares = (finalCarbon * pool.totalShares) / pool.carbonReserve;
    
    // Update pool state
    pool.carbonReserve += finalCarbon;
    pool.stableReserve += finalStable;
    pool.totalShares += shares;
    
    return shares;
  }
  
  // Remove liquidity from pool
  async removeLiquidity(
    projectId: string,
    shares: bigint
  ): Promise<[bigint, bigint]> {
    const pool = this.pools.get(projectId);
    if (!pool) throw new Error('Pool not found');
    
    const carbonAmount = (shares * pool.carbonReserve) / pool.totalShares;
    const stableAmount = (shares * pool.stableReserve) / pool.totalShares;
    
    pool.carbonReserve -= carbonAmount;
    pool.stableReserve -= stableAmount;
    pool.totalShares -= shares;
    
    return [carbonAmount, stableAmount];
  }
  
  // Swap stable tokens for carbon credits
  async swapStableForCarbon(
    projectId: string,
    stableAmount: bigint,
    minCarbonOut: bigint
  ): Promise<bigint> {
    const pool = this.pools.get(projectId);
    if (!pool) throw new Error('Pool not found');
    
    // Apply 0.3% trading fee
    const stableAmountWithFee = (stableAmount * BigInt(997)) / BigInt(1000);
    
    // Calculate carbon output using constant product formula
    const numerator = stableAmountWithFee * pool.carbonReserve;
    const denominator = pool.stableReserve + stableAmountWithFee;
    const carbonOut = numerator / denominator;
    
    if (carbonOut < minCarbonOut) {
      throw new Error('Insufficient output amount');
    }
    
    // Update pool reserves
    pool.carbonReserve -= carbonOut;
    pool.stableReserve += stableAmount;
    pool.lastPrice = (pool.stableReserve * BigInt(1e18)) / pool.carbonReserve;
    pool.volume24h += stableAmount;
    
    return carbonOut;
  }
  
  // Swap carbon credits for stable tokens
  async swapCarbonForStable(
    projectId: string,
    carbonAmount: bigint,
    minStableOut: bigint
  ): Promise<bigint> {
    const pool = this.pools.get(projectId);
    if (!pool) throw new Error('Pool not found');
    
    const carbonAmountWithFee = (carbonAmount * BigInt(997)) / BigInt(1000);
    
    const numerator = carbonAmountWithFee * pool.stableReserve;
    const denominator = pool.carbonReserve + carbonAmountWithFee;
    const stableOut = numerator / denominator;
    
    if (stableOut < minStableOut) {
      throw new Error('Insufficient output amount');
    }
    
    pool.carbonReserve += carbonAmount;
    pool.stableReserve -= stableOut;
    pool.lastPrice = (pool.stableReserve * BigInt(1e18)) / pool.carbonReserve;
    pool.volume24h += stableOut;
    
    return stableOut;
  }
  
  // Get current price for carbon credits
  getPrice(projectId: string): bigint {
    const pool = this.pools.get(projectId);
    if (!pool) return BigInt(0);
    
    return (pool.stableReserve * BigInt(1e18)) / pool.carbonReserve;
  }
  
  // Calculate slippage for trade
  calculateSlippage(
    projectId: string,
    inputAmount: bigint,
    isStableInput: boolean
  ): number {
    const pool = this.pools.get(projectId);
    if (!pool) return 0;
    
    const currentPrice = this.getPrice(projectId);
    
    let newPrice: bigint;
    if (isStableInput) {
      const carbonOut = this.swapStableForCarbon(projectId, inputAmount, BigInt(0));
      newPrice = (pool.stableReserve * BigInt(1e18)) / pool.carbonReserve;
    } else {
      const stableOut = this.swapCarbonForStable(projectId, inputAmount, BigInt(0));
      newPrice = (pool.stableReserve * BigInt(1e18)) / pool.carbonReserve;
    }
    
    const slippage = Number(
      ((newPrice - currentPrice) * BigInt(10000)) / currentPrice
    ) / 100;
    
    return Math.abs(slippage);
  }
  
  // Helper function for square root calculation
  private sqrt(value: bigint): bigint {
    if (value < BigInt(0)) {
      throw new Error('Square root of negative number');
    }
    if (value < BigInt(2)) {
      return value;
    }
    
    let x = value;
    let y = (x + BigInt(1)) / BigInt(2);
    
    while (y < x) {
      x = y;
      y = (x + value / x) / BigInt(2);
    }
    
    return x;
  }
}

export default CarbonCreditAMM;

// CarbonCreditDashboard.tsx - Main user interface

import React, { useState, useEffect } from 'react';
import { ethers } from 'ethers';
import CarbonCreditAMM from './CarbonCreditAMM';

interface Project {
  id: string;
  name: string;
  location: string;
  methodology: string;
  verified: boolean;
  price: number;
  apy: number;
  totalStaked: number;
}

const CarbonCreditDashboard: React.FC = () => {
  const [projects, setProjects] = useState<Project[]>([]);
  const [userBalance, setUserBalance] = useState<number>(0);
  const [stakedAmount, setStakedAmount] = useState<number>(0);
  const [selectedProject, setSelectedProject] = useState<string>('');
  const [stakeAmount, setStakeAmount] = useState<string>('');
  const [loading, setLoading] = useState<boolean>(false);
  
  // Mock project data - replace with real API calls
  useEffect(() => {
    const mockProjects: Project[] = [
      {
        id: 'FOREST-001',
        name: 'Amazon Rainforest Preservation',
        location: 'Brazil',
        methodology: 'REDD+',
        verified: true,
        price: 45.2,
        apy: 12.5,
        totalStaked: 125000
      },
      {
        id: 'SOLAR-002',
        name: 'Community Solar Farm',
        location: 'India',
        methodology: 'Grid-Connected Renewable Energy',
        verified: true,
        price: 38.7,
        apy: 8.3,
        totalStaked: 89000
      },
      {
        id: 'MANGROVE-003',
        name: 'Mangrove Restoration Project',
        location: 'Philippines',
        methodology: 'Blue Carbon',
        verified: true,
        price: 52.1,
        apy: 15.2,
        totalStaked: 67000
      }
    ];
    
    setProjects(mockProjects);
  }, []);
  
  const handleStake = async () => {
    if (!selectedProject || !stakeAmount) return;
    
    setLoading(true);
    try {
      // Connect to wallet
      if (typeof window.ethereum !== 'undefined') {
        const provider = new ethers.BrowserProvider(window.ethereum);
        await provider.send("eth_requestAccounts", []);
        const signer = await provider.getSigner();
        
        // Execute staking transaction
        // This would connect to your deployed contracts
        console.log(`Staking ${stakeAmount} credits in project ${selectedProject}`);
        
        // Update UI state
        setStakedAmount(prev => prev + parseFloat(stakeAmount));
        setStakeAmount('');
        
        alert('Staking successful! You are now earning environmental yields.');
      }
    } catch (error) {
      console.error('Staking failed:', error);
      alert('Staking failed. Please try again.');
    } finally {
      setLoading(false);
    }
  };
  
  return (
    <div className="max-w-6xl mx-auto p-6 bg-gray-50 min-h-screen">
      <header className="mb-8">
        <h1 className="text-3xl font-bold text-green-800 mb-2">
          Carbon Credit Yield Farm
        </h1>
        <p className="text-gray-600">
          Earn yields while saving the planet. Stake carbon credits and watch your environmental impact grow.
        </p>
      </header>
      
      {/* User Stats */}
      <div className="grid grid-cols-1 md:grid-cols-3 gap-6 mb-8">
        <div className="bg-white p-6 rounded-lg shadow-md">
          <h3 className="text-lg font-semibold text-gray-700 mb-2">
            Available Balance
          </h3>
          <p className="text-2xl font-bold text-green-600">
            {userBalance.toLocaleString()} CCT
          </p>
        </div>
        
        <div className="bg-white p-6 rounded-lg shadow-md">
          <h3 className="text-lg font-semibold text-gray-700 mb-2">
            Total Staked
          </h3>
          <p className="text-2xl font-bold text-blue-600">
            {stakedAmount.toLocaleString()} CCT
          </p>
        </div>
        
        <div className="bg-white p-6 rounded-lg shadow-md">
          <h3 className="text-lg font-semibold text-gray-700 mb-2">
            Pending Rewards
          </h3>
          <p className="text-2xl font-bold text-purple-600">
            {(stakedAmount * 0.15 / 365).toFixed(2)} CCT
          </p>
        </div>
      </div>
      
      {/* Staking Interface */}
      <div className="bg-white p-6 rounded-lg shadow-md mb-8">
        <h2 className="text-xl font-semibold mb-4">Stake Carbon Credits</h2>
        
        <div className="grid grid-cols-1 md:grid-cols-3 gap-4 mb-4">
          <select
            value={selectedProject}
            onChange={(e) => setSelectedProject(e.target.value)}
            className="border border-gray-300 rounded-md p-2"
          >
            <option value="">Select Project</option>
            {projects.map(project => (
              <option key={project.id} value={project.id}>
                {project.name} ({project.apy}% APY)
              </option>
            ))}
          </select>
          
          <input
            type="number"
            placeholder="Amount to stake"
            value={stakeAmount}
            onChange={(e) => setStakeAmount(e.target.value)}
            className="border border-gray-300 rounded-md p-2"
          />
          
          <button
            onClick={handleStake}
            disabled={loading || !selectedProject || !stakeAmount}
            className="bg-green-600 text-white px-4 py-2 rounded-md hover:bg-green-700 disabled:opacity-50"
          >
            {loading ? 'Staking...' : 'Stake Credits'}
          </button>
        </div>
      </div>
      
      {/* Project List */}
      <div className="bg-white rounded-lg shadow-md overflow-hidden">
        <h2 className="text-xl font-semibold p-6 border-b">
          Available Projects
        </h2>
        
        <div className="overflow-x-auto">
          <table className="w-full">
            <thead className="bg-gray-50">
              <tr>
                <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                  Project
                </th>
                <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                  Location
                </th>
                <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                  Methodology
                </th>
                <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                  Price
                </th>
                <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                  APY
                </th>
                <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                  Total Staked
                </th>
                <th className="px-6 py-3 text-left text-xs font-medium text-gray-500 uppercase tracking-wider">
                  Status
                </th>
              </tr>
            </thead>
            <tbody className="bg-white divide-y divide-gray-200">
              {projects.map(project => (
                <tr key={project.id} className="hover:bg-gray-50">
                  <td className="px-6 py-4 whitespace-nowrap">
                    <div className="text-sm font-medium text-gray-900">
                      {project.name}
                    </div>
                    <div className="text-sm text-gray-500">
                      {project.id}
                    </div>
                  </td>
                  <td className="px-6 py-4 whitespace-nowrap text-sm text-gray-900">
                    {project.location}
                  </td>
                  <td className="px-6 py-4 whitespace-nowrap text-sm text-gray-900">
                    {project.methodology}
                  </td>
                  <td className="px-6 py-4 whitespace-nowrap text-sm text-gray-900">
                    ${project.price}
                  </td>
                  <td className="px-6 py-4 whitespace-nowrap text-sm text-gray-900">
                    <span className="text-green-600 font-semibold">
                      {project.apy}%
                    </span>
                  </td>
                  <td className="px-6 py-4 whitespace-nowrap text-sm text-gray-900">
                    {project.totalStaked.toLocaleString()} CCT
                  </td>
                  <td className="px-6 py-4 whitespace-nowrap">
                    {project.verified ? (
                      <span className="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-green-100 text-green-800">
                        Verified
                      </span>
                    ) : (
                      <span className="inline-flex items-center px-2.5 py-0.5 rounded-full text-xs font-medium bg-yellow-100 text-yellow-800">
                        Pending
                      </span>
                    )}
                  </td>
                </tr>
              ))}
            </tbody>
          </table>
        </div>
      </div>
    </div>
  );
};

export default CarbonCreditDashboard;

# Install dependencies
npm install --save-dev hardhat @nomiclabs/hardhat-waffle @nomiclabs/hardhat-ethers
npm install @openzeppelin/contracts @chainlink/contracts

# Create deployment script
mkdir scripts
touch scripts/deploy.js

// scripts/deploy.js
const { ethers } = require("hardhat");

async function main() {
  console.log("Deploying Carbon Credit Platform...");
  
  // Deploy Carbon Credit Token
  const CarbonCreditToken = await ethers.getContractFactory("CarbonCreditToken");
  const carbonToken = await CarbonCreditToken.deploy();
  await carbonToken.deployed();
  console.log("CarbonCreditToken deployed to:", carbonToken.address);
  
  // Deploy mock reward token for testing
  const MockERC20 = await ethers.getContractFactory("MockERC20");
  const rewardToken = await MockERC20.deploy("Environmental Reward Token", "ERT");
  await rewardToken.deployed();
  console.log("RewardToken deployed to:", rewardToken.address);
  
  // Deploy Environmental Yield Farm
  const EnvironmentalYieldFarm = await ethers.getContractFactory("EnvironmentalYieldFarm");
  const yieldFarm = await EnvironmentalYieldFarm.deploy(
    carbonToken.address,
    rewardToken.address
  );
  await yieldFarm.deployed();
  console.log("EnvironmentalYieldFarm deployed to:", yieldFarm.address);
  
  // Deploy Verification Oracle
  const CarbonVerificationOracle = await ethers.getContractFactory("CarbonVerificationOracle");
  const verificationOracle = await CarbonVerificationOracle.deploy(carbonToken.address);
  await verificationOracle.deployed();
  console.log("CarbonVerificationOracle deployed to:", verificationOracle.address);
  
  // Grant verifier role to oracle
  const VERIFIER_ROLE = await carbonToken.VERIFIER_ROLE();
  await carbonToken.grantRole(VERIFIER_ROLE, verificationOracle.address);
  console.log("Granted verifier role to oracle");
  
  // Add sample project to yield farm
  await yieldFarm.addProject(
    "FOREST-001",
    ethers.utils.parseEther("1"), // 1 reward token per second
    2 // 2x impact multiplier for high-quality forestry projects
  );
  console.log("Added sample project to yield farm");
  
  console.log("\nDeployment Summary:");
  console.log("==================");
  console.log("CarbonCreditToken:", carbonToken.address);
  console.log("RewardToken:", rewardToken.address);
  console.log("EnvironmentalYieldFarm:", yieldFarm.address);
  console.log("CarbonVerificationOracle:", verificationOracle.address);
}

main()
  .then(() => process.exit(0))
  .catch((error) => {
    console.error(error);
    process.exit(1);
  });

// test/CarbonCredit.test.js
const { expect } = require("chai");
const { ethers } = require("hardhat");

describe("Carbon Credit Platform", function () {
  let carbonToken, yieldFarm, rewardToken, owner, addr1, addr2;
  
  beforeEach(async function () {
    [owner, addr1, addr2] = await ethers.getSigners();
    
    // Deploy contracts
    const CarbonCreditToken = await ethers.getContractFactory("CarbonCreditToken");
    carbonToken = await CarbonCreditToken.deploy();
    
    const MockERC20 = await ethers.getContractFactory("MockERC20");
    rewardToken = await MockERC20.deploy("Environmental Reward Token", "ERT");
    
    const EnvironmentalYieldFarm = await ethers.getContractFactory("EnvironmentalYieldFarm");
    yieldFarm = await EnvironmentalYieldFarm.deploy(
      carbonToken.address,
      rewardToken.address
    );
    
    // Setup project
    await yieldFarm.addProject("TEST-001", ethers.utils.parseEther("1"), 1);
  });
  
  it("Should mint carbon credits with metadata", async function () {
    await carbonToken.mintCarbonCredit(
      addr1.address,
      ethers.utils.parseEther("100"),
      "TEST-001",
      "VCS",
      1640995200, // 2022 timestamp
      "12.34,-56.78"
    );
    
    expect(await carbonToken.balanceOf(addr1.address)).to.equal(
      ethers.utils.parseEther("100")
    );
    
    const creditInfo = await carbonToken.getCreditInfo(1);
    expect(creditInfo.projectId).to.equal("TEST-001");
    expect(creditInfo.methodology).to.equal("VCS");
  });
  
  it("Should stake credits and earn rewards", async function () {
    // Mint credits to user
    await carbonToken.mintCarbonCredit(
      addr1.address,
      ethers.utils.parseEther("100"),
      "TEST-001",
      "VCS",
      1640995200,
      "12.34,-56.78"
    );
    
    // Approve and stake
    await carbonToken.connect(addr1).approve(
      yieldFarm.address,
      ethers.utils.parseEther("50")
    );
    
    await yieldFarm.connect(addr1).stake("TEST-001", ethers.utils.parseEther("50"));
    
    // Check staked amount
    const userInfo = await yieldFarm.userInfo(addr1.address, "TEST-001");
    expect(userInfo.stakedAmount).to.equal(ethers.utils.parseEther("50"));
  });
  
  it("Should retire credits permanently", async function () {
    await carbonToken.mintCarbonCredit(
      addr1.address,
      ethers.utils.parseEther("100"),
      "TEST-001",
      "VCS",
      1640995200,
      "12.34,-56.78"
    );
    
    await carbonToken.connect(addr1).retireCredits(
      1,
      ethers.utils.parseEther("25"),
      "Corporate neutrality"
    );
    
    expect(await carbonToken.balanceOf(addr1.address)).to.equal(
      ethers.utils.parseEther("75")
    );
    
    expect(await carbonToken.totalRetired()).to.equal(
      ethers.utils.parseEther("25")
    );
  });
});

# Build and deploy React frontend
npm run build

# Deploy to IPFS for decentralized hosting
npm install -g ipfs-deploy
ipd build/ --no-clipboard

function batchMintCredits(
    address[] memory recipients,
    uint256[] memory amounts,
    string[] memory projectIds
) external onlyRole(VERIFIER_ROLE) {
    require(recipients.length == amounts.length, "Array length mismatch");
    
    for (uint256 i = 0; i < recipients.length; i++) {
        mintCarbonCredit(
            recipients[i],
            amounts[i],
            projectIds[i],
            "VCS", // Default methodology
            block.timestamp,
            "" // Default location
        );
    }
}

contract CarbonCreditBridge {
    mapping(uint256 => bool) public processedNonces;
    
    event BridgeTransfer(
        address indexed from,
        address indexed to,
        uint256 amount,
        uint256 targetChain,
        uint256 nonce
    );
    
    function bridgeToChain(
        uint256 amount,
        uint256 targetChain,
        address recipient
    ) external {
        carbonToken.burn(msg.sender, amount);
        
        uint256 nonce = block.timestamp + block.difficulty;
        
        emit BridgeTransfer(msg.sender, recipient, amount, targetChain, nonce);
    }
}

contract ComplianceReporting {
    struct Transaction {
        address from;
        address to;
        uint256 amount;
        uint256 timestamp;
        string transactionType; // "mint", "transfer", "retire"
    }
    
    Transaction[] public transactions;
    mapping(address => uint256[]) public userTransactions;
    
    function generateComplianceReport(
        address user,
        uint256 startTime,
        uint256 endTime
    ) external view returns (Transaction[] memory) {
        uint256[] memory userTxIndices = userTransactions[user];
        Transaction[] memory filteredTxs = new Transaction[](userTxIndices.length);
        uint256 count = 0;
        
        for (uint256 i = 0; i < userTxIndices.length; i++) {
            Transaction memory tx = transactions[userTxIndices[i]];
            if (tx.timestamp >= startTime && tx.timestamp <= endTime) {
                filteredTxs[count] = tx;
                count++;
            }
        }
        
        return filteredTxs;
    }
}

class CarbonCreditAnalytics {
  async getMarketMetrics() {
    return {
      totalValueLocked: await this.getTotalValueLocked(),
      dailyVolume: await this.getDailyTradingVolume(),
      activePools: await this.getActivePoolCount(),
      averageAPY: await this.getAverageAPY(),
      carbonRetired: await this.getTotalCarbonRetired()
    };
  }
  
  async getTotalValueLocked(): Promise<number> {
    // Calculate total value of staked carbon credits
    const pools = await this.getAllPools();
    return pools.reduce((total, pool) => {
      return total + (pool.totalStaked * pool.currentPrice);
    }, 0);
  }
  
  async getProjectPerformance(projectId: string) {
    return {
      totalStaked: await this.getProjectStaked(projectId),
      averagePrice: await this.getAveragePrice(projectId),
      volatility: await this.calculateVolatility(projectId),
      stakingAPY: await this.getCurrentAPY(projectId),
      verificationScore: await this.getVerificationScore(projectId)
    };
  }
}