solidity-assignments-vigneshjraju

solidity-assignments-vigneshjraju created by GitHub Classroom

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

contract StudentManagementSystem { // Define student structure enum Department { CS, EC, ME }

struct Student {
    string name;
    uint8 sem;
    Department dept;
    uint256 cgpa;
    uint256 rollNo;
    address studentAddress;
}

address public staffAdvisor;
Student[] public students;

// Map address to index in the array for easy update
mapping(address => uint256) private studentIndex;
mapping(address => bool) public isStudent;

constructor() {
    staffAdvisor = msg.sender; // deployer is staff advisor
}

// Modifier: Only staff advisor can do this
modifier onlyStaffAdvisor() {
    require(msg.sender == staffAdvisor, "Only staff advisor allowed");
    _;
}

// Modifier: Only student can do this
modifier onlyStudent() {
    require(isStudent[msg.sender], "Only student allowed");
    _;
}

// Add a new student (only by staff advisor)
function addStudent(
    string memory _name,
    uint8 _sem,
    Department _dept,
    uint256 _cgpa,
    uint256 _rollNo,
    address _studentAddress
) public onlyStaffAdvisor {
    Student memory s = Student(_name, _sem, _dept, _cgpa, _rollNo, _studentAddress);
    students.push(s);
    studentIndex[_studentAddress] = students.length - 1;
    isStudent[_studentAddress] = true;
}

// Staff advisor can edit full student details
function editStudent(
    address _studentAddress,
    string memory _name,
    uint8 _sem,
    Department _dept,
    uint256 _cgpa,
    uint256 _rollNo
) public onlyStaffAdvisor {
    uint256 index = studentIndex[_studentAddress];
    students[index] = Student(_name, _sem, _dept, _cgpa, _rollNo, _studentAddress);
}

// Student can only update their name
function updateMyName(string memory _newName) public onlyStudent {
    uint256 index = studentIndex[msg.sender];
    students[index].name = _newName;
}

// Staff advisor can view any student details by index
function getStudent(uint256 _index) public view onlyStaffAdvisor returns (
    string memory name,
    uint8 sem,
    Department dept,
    uint256 cgpa,
    uint256 rollNo,
    address studentAddress
) {
    Student memory s = students[_index];
    return (s.name, s.sem, s.dept, s.cgpa, s.rollNo, s.studentAddress);
}

// Get number of students
function getStudentCount() public view returns (uint256) {
    return students.length;
}

}