#include <iostream>
#include <fstream>
#include <vector>
#include <string>
#include <algorithm>
#include <sstream>

using namespace std;

struct Note {
    string title;
    string content;
    string type;
    string deadlineDate;
    bool done;
};

void displayMenu();
void addNewNote(vector<Note> &notes);
void listNotes(const vector<Note> &notes);
void editNote(vector<Note> &notes);
void markNoteAsDone(vector<Note> &notes);
void deleteNote(vector<Note> &notes);
void saveNotes(const vector<Note> &notes);
void loadNotes(vector<Note> &notes);
bool isTitleUnique(const vector<Note> &notes, const string &title);
bool isValidType(const string &type);
bool isValidDate(const string &deadlineDate);
bool isFileEmpty(const string &filename);
void writeHeader(ofstream &outFile);   

int main() {
    vector<Note> notes;
    loadNotes(notes); 

    int choice;
    do {
        displayMenu();
        cout << "Enter your choice: ";
        cin >> choice;

        switch (choice) {
            case 1:
                addNewNote(notes);
                break;
            case 2:
                listNotes(notes);
                break;
            case 3:
                editNote(notes);
                break;
            case 4:
                markNoteAsDone(notes);
                break;
            case 5:
                deleteNote(notes);
                break;
            case 0:
                
                saveNotes(notes);
                cout << "Exiting the program. Goodbye!" << endl;
                break;
            default:
                cout << "Invalid choice. Please try again." << endl;
        }
    } while (choice != 0);

    return 0;
}

void displayMenu() {
    cout << "*********MAIN MENU**********" << endl;
    cout << "(1) Add new note" << endl;
    cout << "(2) List notes" << endl;
    cout << "(3) Edit note" << endl;
    cout << "(4) Mark note as done" << endl;
    cout << "(5) Delete note" << endl;
    cout << "(0) Exit" << endl;
    cout << "****************************" << endl;
}

void addNewNote(vector<Note> &notes) {
    // ignore inputan sebelumnya
    Note newNote;
    cin.ignore(); 

   // lakukan perulangan
    do {
        //lakukan terus menerus
        // tampilakan cout berikut
        cout << "Enter title (must be unique and without spaces): ";
        // ambil inputan dan jadikan inputan menjadi title
        getline(cin, newNote.title);
        //sampai while ini terpenuhi
    } while (!isTitleUnique(notes, newNote.title) || newNote.title.find(' ') != string::npos);

    cout << "Enter content: ";
    getline(cin, newNote.content);


    do {
        cout << "Enter type (important/not_important): ";
        cin >> newNote.type;
    } while (!isValidType(newNote.type));


    do {
        cout << "Enter date (YYYY-MM-DD): ";
        cin >> newNote.deadlineDate;
    } while (!isValidDate(newNote.deadlineDate));

    newNote.done = false;

    notes.push_back(newNote);
    saveNotes(notes); 
    cout << "Note added successfully!" << endl;
}

void listNotes(const vector<Note> &notes) {
    if (notes.empty()) {
        cout << "No notes available." << endl;
    } else {
        cout << "*********LIST OF NOTES**********" << endl;
        for (const auto &note : notes) {
            cout << "Title: " << note.title << endl;
            cout << "Content: " << note.content << endl;
            cout << "Type: " << note.type << endl;
            cout << "Deadline Date: " << note.deadlineDate << endl;
            cout << "Status: " << (note.done ? "Done" : "Not Done") << endl;
            cout << "-------------------------------" << endl;
        }
        cout << "*********************************" << endl;
    }
}

void editNote(vector<Note> &notes) {
    cin.ignore(); 
    cout << "Enter the title of the note you want to edit: ";
    string searchTitle;
    getline(cin, searchTitle);

    bool found = false;
    for (auto &note : notes) {
        if (note.title == searchTitle) {
            
            do {
                cout << "Enter new title (must be unique and without spaces): ";
                getline(cin, searchTitle);
            } while (!isTitleUnique(notes, searchTitle) || searchTitle.find(' ') != string::npos);
            note.title = searchTitle;

            cout << "Enter new content: ";
            getline(cin, note.content);

           
            do {
                cout << "Enter new type (important/not_important): ";
                cin >> note.type;
            } while (!isValidType(note.type));

            
            do {
                cout << "Enter new date (YYYY-MM-DD): ";
                cin >> note.deadlineDate;
            } while (!isValidDate(note.deadlineDate));

            cout << "Note edited successfully!" << endl;
            found = true;
            saveNotes(notes); 
            break;
        }
    }

    if (!found) {
        cout << "Note with title '" << searchTitle << "' not found." << endl;
    }
}

void markNoteAsDone(vector<Note> &notes) {
    cin.ignore(); 
    cout << "Enter the title of the note you want to mark as done: ";
    string searchTitle;
    getline(cin, searchTitle);

    bool found = false;
    for (auto &note : notes) {
        if (note.title == searchTitle) {
            note.done = true;
            cout << "Note marked as done!" << endl;
            found = true;
            saveNotes(notes);
            break;
        }
    }

    if (!found) {
        cout << "Note with title '" << searchTitle << "' not found." << endl;
    }
}

struct NoteWithTitle {
    string searchTitle;

    NoteWithTitle(const string &title) : searchTitle(title) {}

    bool operator()(const Note &note) const {
        return note.title == searchTitle;
    }
};

void deleteNote(vector<Note> &notes) {
    cin.ignore(); 
    cout << "Enter the title of the note you want to delete: ";
    string searchTitle;
    getline(cin, searchTitle);

    NoteWithTitle noteWithTitle(searchTitle);

    auto it = remove_if(notes.begin(), notes.end(), noteWithTitle);

    if (it != notes.end()) {
        notes.erase(it, notes.end());
        cout << "Note deleted successfully!" << endl;
        saveNotes(notes); 
    } else {
        cout << "Note with title '" << searchTitle << "' not found." << endl;
    }
}



void saveNotes(const vector<Note> &notes) {
    ofstream outFile("notes.csv");
    if (outFile.is_open()) {
        if (isFileEmpty("notes.csv")) {
             cout << "is emtpy" << endl;
            
            writeHeader(outFile);
        }else{
            cout << "is npt emtpy" << endl;
        }
        
        for (const auto &note : notes) {
            outFile << note.title << "," << note.content << "," << note.type << "," << note.deadlineDate << "," << note.done << endl;
        }
        outFile.close();
        cout << "Notes saved to file." << endl;
    } else {
        cerr << "Unable to open file for saving notes." << endl;
    }
}

bool isFileEmpty(const string &filename) {
    ifstream file(filename);
    return file.peek() == ifstream::traits_type::eof();
}

void writeHeader(ofstream &outFile) {
    outFile << "title,content,type,deadline_date,done" << endl;
}

void loadNotes(vector<Note> &notes) {
    ifstream inFile("notes.csv");
    if (inFile.is_open()) {
        Note temp;
        while (getline(inFile, temp.title, ',')) {
            getline(inFile, temp.content, ',');
            getline(inFile, temp.type, ',');
            getline(inFile, temp.deadlineDate, ',');
            string done;
            getline(inFile, done);
            temp.done = (done == "1");
            notes.push_back(temp);
        }
        inFile.close();
        cout << "Notes loaded from file." << endl;
    } else {
        cout << "No existing notes file found. Creating a new one." << endl;
    }
}

bool isTitleUnique(const vector<Note> &notes, const string &title) {
    string lowerTitle = title;
    transform(lowerTitle.begin(), lowerTitle.end(), lowerTitle.begin(), ::tolower);

    for (const auto &note : notes) {
        string lowerNoteTitle = note.title;
        transform(lowerNoteTitle.begin(), lowerNoteTitle.end(), lowerNoteTitle.begin(), ::tolower);

        if (lowerNoteTitle == lowerTitle) {
            cout << "Title '" << title << "' already exists. Please enter a different title." << endl;
            return false;
        }
    }
    return true;
}

bool isValidType(const string &type) {
    string lowercaseType = type;
    transform(lowercaseType.begin(), lowercaseType.end(), lowercaseType.begin(), ::tolower);

    if (lowercaseType == "important" || lowercaseType == "not_important") {
        return true;
    } else {
        cout << "Invalid type. Please enter 'important' or 'not_important'." << endl;
        return false;
    }
}

bool isValidDate(const string &deadlineDate) {
    if (deadlineDate.length() != 10) {
        cout << "Invalid date format. Please enter the date in the format YYYY-MM-DD." << endl;
        return false;
    }

    try {
        int year = stoi(deadlineDate.substr(0, 4));
        int month = stoi(deadlineDate.substr(5, 2));
        int day = stoi(deadlineDate.substr(8, 2));

        if (year < 1000 || year > 9999 || month < 1 || month > 12 || day < 1 || day > 31) {
            cout << "Invalid date. Please enter a valid date." << endl;
            return false;
        }

        
        if ((month == 4 || month == 6 || month == 9 || month == 11) && day > 30) {
            cout << "Invalid date. Month " << month << " has 30 days or less." << endl;
            return false;
        }

       
        if (month == 2) {
            bool isLeapYear = (year % 4 == 0 && (year % 100 != 0 || year % 400 == 0));
            if ((isLeapYear && day > 29) || (!isLeapYear && day > 28)) {
                cout << "Invalid date. February in year " << year << " has " << (isLeapYear ? "29" : "28") << " days." << endl;
                return false;
            }
        }

        return true;
    } catch (const invalid_argument &) {
        cout << "Invalid date format. Please enter the date in the format YYYY-MM-DD." << endl;
        return false;
    }
}