main.cpp

#include <iostream>

#include "InputUtils.h"
#include "FileManager.h"
#include "StudentRepository.h"

int main() {
    Node* head = nullptr;
    loadFromFile(head, "students.csv");

    int choice = -1;
    while (true) {
        std::cout << "\n==== Student Management ====\n";
        std::cout << "1. Add student\n";
        std::cout << "2. Display all students\n";
        std::cout << "3. Search student by ID\n";
        std::cout << "4. Search student by name\n";
        std::cout << "5. Update student by ID\n";
        std::cout << "6. Delete student by ID\n";
        std::cout << "7. Save to file\n";
        std::cout << "8. Statistics (total, avg, min, max)\n";
        std::cout << "9. Sort (ID/Name/Average)\n";
        std::cout << "0. Exit\n";
        std::cout << "Choice: ";
        
        if (!(std::cin >> choice)) {
            std::cin.clear();
            std::cin.ignore(10000, '\n');
            std::cout << "Invalid input\n";
            continue;
        }

        // exit code is 0
        if (choice == 0) {
            saveToFile(head, "students.csv");
            clearList(head);
            std::cout << "Goodbye\n";
            break;
        }
        std::cin.ignore(10000, '\n');

        // Choices from 1 to 9
        switch (choice) 
        {
            case 1: {
                addStudent(head);
                saveToFile(head, "students.csv");
                break;
            }

            case 2: {
                displayStudents(head);
                break;
            }

            case 3: {
                int id = getIntInput("Enter ID: ");
                Student* s = findStudentByID(head, id);
                if (s) s->displayInfo(); else std::cout << "Not found\n";
                break;
            }

            case 4: {
                std::string name = getStringInput("Enter name (exact match): ");
                // linear search by name
                Node* cur = head;
                bool found = false;
                while (cur) {
                    if (cur->student && cur->student->getName() == name) {
                        cur->student->displayInfo(); found = true;
                    }
                    cur = cur->next;
                }
                if (!found) std::cout << "No students found with that name.\n";
                break;
            }

            case 5: {
                int id = getIntInput("Enter ID to update: ");
                updateStudent(head, id);
                saveToFile(head, "students.csv");
                break;
            }

            case 6: {
                int id = getIntInput("Enter ID to delete: ");
                deleteStudent(head, id);
                saveToFile(head, "students.csv");
                break;
            }

            case 7: {
                saveToFile(head, "students.csv");
                break;
            }

            case 8: {
                // statistics
                int total = 0;
                float sumAll = 0.0f;
                float maxGrade = -1e9f, minGrade = 1e9f;
                Node* cur = head;
                while (cur) {
                    if (cur->student) {
                        ++total;
                        float avg = cur->student->calculateAverage();
                        sumAll += avg;
                        // per-student min/max over their grades
                        for (int i = 0; i < cur->student->getGradesCount(); ++i) {
                            float g = cur->student->getGrade(i);
                            if (g > maxGrade) maxGrade = g;
                            if (g < minGrade) minGrade = g;
                        }
                    }
                    cur = cur->next;
                }
                std::cout << "Total students: " << total << "\n";
                if (total > 0) std::cout << "Average of student averages: " << (sumAll / total) << "\n";
                if (maxGrade > -1e8f) std::cout << "Highest grade: " << maxGrade << "\n";
                if (minGrade < 1e8f) std::cout << "Lowest grade: " << minGrade << "\n";
                break;
            }

            case 9: {
                std::cout << "Sort by: 1) ID  2) Name  3) Average\nChoice: ";
                int c;
                if (!(std::cin >> c)) { std::cin.clear(); std::cin.ignore(10000,'\n'); continue; }
                std::cin.ignore(10000,'\n');
                if (c == 1) sortByID(head);
                else if (c == 2) sortByName(head);
                else if (c == 3) sortByAverage(head);
                else std::cout << "Unknown sort choice\n";
                saveToFile(head, "students.csv");
                break;
            }

            default: {
                std::cout << "Invalid Input!";
                break;
            }
        }
    }

    return 0;
}