🏥 Confidential Medical Records System

Blockchain medical records system with end-to-end encryption using Oasis Sapphire.

🎯 Features

✅ Automatic Encryption: All data is encrypted on blockchain ✅ Access Control: Patients authorize which doctors can view their data ✅ Guaranteed Privacy: Data inaccessible without permissions ✅ Immutable: Permanent and verifiable medical history ✅ Easy to Use: Intuitive web interface

---

📊 Stored Data (Encrypted)

1. Affiliation Data

• Full name
• Age
• Gender
• Blood type
• Address
• Phone
• Email
• Social Security Number

2. Existing Diseases

• Disease name
• Diagnosis description
• Diagnosis date
• Severity (Mild, Moderate, Severe)
• Status (Active/Inactive)
• Treatment

3. Medical History

• Personal: Surgeries, past illnesses, allergies
• Family: Hereditary conditions, family history

---

🚀 Installation and Setup

Prerequisites

• Node.js v18+
• npm or yarn
• MetaMask installed
• TEST tokens from Sapphire Testnet

1. Clone and Install Backend

cd medical-records-sapphire
npm install

2. Configure Environment Variables

cp .env.example .env

Edit .env and add your private key:

PRIVATE_KEY=0xtu_clave_privada_aqui

⚠️ NEVER share your private key or upload it to git.

3. Get Testnet Tokens

1. Go to https://faucet.testnet.oasis.io/
2. Select "Sapphire"
3. Enter your address
4. Get 100 TEST tokens

4. Compile Contracts

npx hardhat compile

5. Run Tests (Optional)

# Option 1: Tests on Hardhat Network
npx hardhat test

# Option 2: Tests on Sapphire Localnet (more realistic)
# Terminal 1: Start localnet
docker run -it -p 8545:8545 ghcr.io/oasisprotocol/sapphire-localnet

# Terminal 2: Run tests
npx hardhat test --network sapphire-localnet

6. Deploy to Testnet

npx hardhat run scripts/deploy.js --network sapphire-testnet

Save the contract address that appears in the console.

7. Configure Frontend

cd frontend
npm install

Create the .env file:

cp .env.example .env

Edit frontend/.env:

VITE_CONTRACT_ADDRESS=0xDireccion_Del_Contrato_Desplegado
VITE_NETWORK=testnet

8. Start Frontend

npm run dev

Open http://localhost:3000 in your browser.

---

🔧 Configure MetaMask

Add Sapphire Testnet manually:

1. Open MetaMask
2. Click on the network selector
3. "Add Network" → "Add Network Manually"
4. Enter:

Network Name: Sapphire Testnet
RPC URL: https://testnet.sapphire.oasis.io
Chain ID: 23295
Currency Symbol: TEST
Block Explorer: https://explorer.oasis.io/testnet/sapphire

---

📖 User Guide

As a Patient

1. Register

1. Connect your wallet
2. Go to the "📋 Registro" tab
3. Fill out the form with your data
4. Click "Registrar Paciente"
5. Confirm the transaction in MetaMask

2. Add Diseases

1. Go to "🩺 Enfermedades"
2. Fill in the disease data
3. Save (encrypted transaction)

3. Add Medical History

1. Go to "📚 Antecedentes"
2. Select type (Personal/Family)
3. Add the condition and details

4. View Your Records

1. Go to "👁️ Ver Registros"
2. Leave your address (appears automatically)
3. You will see all your encrypted data

5. Authorize Doctors

1. Go to "🔐 Permisos"
2. Enter the doctor's address
3. Click "Autorizar Médico"
4. The doctor can now view your history

As a Doctor

1. Register as a Doctor

1. Connect your wallet
2. Go to "📋 Registro"
3. Enter your name in "Registrar Médico"

2. Access Patient Records

1. The patient must authorize you first
2. Go to "👁️ Ver Registros"
3. Enter the patient's address
4. You will see their complete history

3. Add Diagnoses

1. Go to "🩺 Enfermedades"
2. Enter the patient's address (who authorized you)
3. Add the disease and treatment

---

🏗️ System Architecture

┌─────────────────────────────────────┐
│         FRONTEND (React)            │
│   - Medical forms                   │
│   - Data visualization              │
│   - Permission management           │
└──────────────┬──────────────────────┘
               │ Wagmi + Sapphire Wrapper
               │ (Automatic encryption)
               ▼
┌─────────────────────────────────────┐
│   SAPPHIRE BLOCKCHAIN (Testnet)     │
│                                     │
│  ┌───────────────────────────────┐ │
│  │  Smart Contract               │ │
│  │  MedicalRecords.sol           │ │
│  │                               │ │
│  │  - Encrypted data in storage  │ │
│  │  - Access control             │ │
│  │  - Granular permissions       │ │
│  └───────────────────────────────┘ │
└─────────────────────────────────────┘

---

🔒 Security and Privacy

How Encryption Works

1. Encrypted Storage: All contract storage is encrypted by default in Sapphire
2. Encrypted Transactions: Wagmi wrapper automatically encrypts transactions
3. TEE (Trusted Execution Environment): Data is only decrypted inside the TEE
4. Access Control: Solidity modifiers prevent unauthorized access

What is NOT Encrypted

⚠️ Events are NOT encrypted. That's why the contract only emits:

• User addresses
• Timestamps
• Action confirmations

Sensitive data like names, diagnoses, etc. are NEVER emitted.

Immutable/Constant Variables

⚠️ IMPORTANT: immutable and constant variables are NOT encrypted because they are stored in the bytecode.

// ❌ BAD - Visible data
bytes32 private constant SECRET = "mi_secreto";

// ✅ GOOD - Encrypted data
bytes32 private secret;

Testnet vs Mainnet

Feature	Testnet	Mainnet
Confidentiality	⚠️ NOT guaranteed	✅ Guaranteed
Cost	🆓 Free	💰 ROSE tokens
Data	🧪 Testing only	🔒 Real data

---

🧪 Testing

Unit Tests

npx hardhat test

Tests with Coverage

npx hardhat coverage

Tests on Sapphire Localnet

# Terminal 1
docker run -it -p 8545:8545 ghcr.io/oasisprotocol/sapphire-localnet

# Terminal 2
npx hardhat test --network sapphire-localnet

---

📂 Project Structure

medical-records-sapphire/
├── contracts/
│   └── MedicalRecords.sol        # Main contract
├── scripts/
│   └── deploy.js                  # Deployment script
├── test/
│   └── MedicalRecords.test.js     # Tests
├── frontend/
│   ├── src/
│   │   ├── components/            # React components
│   │   ├── config/
│   │   │   └── wagmi.js           # Wagmi configuration
│   │   ├── contracts/             # ABIs (generated)
│   │   ├── styles/
│   │   │   └── App.css
│   │   ├── App.jsx
│   │   └── main.jsx
│   ├── index.html
│   ├── package.json
│   └── vite.config.js
├── hardhat.config.js
├── package.json
└── README.md

---

🎨 Screenshots

Patient Registration

Form with all encrypted affiliation fields.

Disease Management

Add diagnoses with severity and treatment.

Permission Control

Authorize/Revoke access to specific doctors.

Records View

Complete encrypted history accessible only with permissions.

---

🚨 Troubleshooting

Error: "Already registered"

• You can only register once per address
• Use another wallet to create another patient

Error: "No tienes permiso"

• Verify that the patient has authorized you
• Confirm that you are registered as a doctor

Transactions fail

• Verify that you have TEST tokens
• Confirm that you are on Sapphire Testnet
• Check MetaMask configuration

Deployed contract not visible

• Copy the correct address to frontend/.env
• Restart the frontend server (npm run dev)

---

🔮 Upcoming Features

Ideas to expand the system:

• Medical Prescriptions: Issue encrypted prescriptions
• Medical Appointments: Scheduling system
• Notifications: Alerts for new diagnoses
• Export PDF: Generate medical reports
• Medical Images: Store X-rays, MRIs (IPFS + encryption)
• Laboratories: Integrate test results
• Pharmacies: Prescription verification
• Insurance: Controlled access for insurers
• Data Update: Modify existing diseases
• Search: Filter by disease type, date, etc.
• Multi-language: Support for multiple languages
• Audit: Log of who accessed what data

---

📚 Additional Documentation

Sapphire

• Docs: https://docs.oasis.io/build/sapphire/
• Quickstart: https://docs.oasis.io/build/sapphire/quickstart/
• Examples: https://github.com/oasisprotocol/sapphire-paratime/tree/main/examples

Wagmi

• Docs: https://wagmi.sh/
• React Hooks: https://wagmi.sh/react/api/hooks

Hardhat

• Docs: https://hardhat.org/docs

---

🤝 Contributing

Contributions are welcome. Please:

1. Fork the project
2. Create a branch for your feature (git checkout -b feature/AmazingFeature)
3. Commit your changes (git commit -m 'Add some AmazingFeature')
4. Push to the branch (git push origin feature/AmazingFeature)
5. Open a Pull Request

---

⚖️ License

MIT License - Free to use for educational and commercial projects.

---

⚠️ Disclaimer

This project is an educational demonstration. For production use with real medical data:

1. ✅ Audit the smart contract
2. ✅ Deploy to Sapphire Mainnet (NOT testnet)
3. ✅ Comply with regulations (HIPAA, GDPR, etc.)
4. ✅ Implement robust authentication
5. ✅ Add additional encryption on the frontend
6. ✅ Backups and disaster recovery
7. ✅ Consult with legal and medical experts

---

📞 Support

Questions or problems?

• Oasis Discord: https://oasis.io/discord
• GitHub Issues: [Your repo here]
• Documentation: README.md

---

🎓 Built With

• Oasis Sapphire - Confidential blockchain
• Solidity - Smart contracts
• Hardhat - Development framework
• React - Frontend
• Wagmi - Ethereum library for React
• Viem - TypeScript Ethereum interface
• Vite - Build tool

---

Made with ❤️ to improve privacy in digital health