// Name: msglm
// Date: Oct 21st, 2022
// Program Name: Menu System 
// Description: CLI, self-servicing kiosk

#include <iostream>
#include <fstream>
#include <vector>
#include <string>
using namespace std;

//Classes

//I would never, ever make this an object in production
//the concept of an "Orderable" is pure data read from a file that should be acted upon, but not act.
class Orderable {
    private:
        string name;
        double price;
    public:
        Orderable(double iprice, string iname) {
            name = iname;
            price = iprice;
        }

        string get_name() {return name;}
        double get_price() {return price;}
};


//Structs
struct foodOrder {
    string name;
    double price;
    int quantity;
};

//Implementation of Nim's readline (https://nim-lang.org/docs/io.html#readLine%2CFile) because 
//I am absolutely sick of having to deal with C++'s obsession with streaming.
//
//I swear if I have to reimplement the entire Nim language in C++20 just 
//to get a compiled language that doesn't increase my chance of stroke 20 fold I will

string readline(ifstream & fileVar) {
    string temp;
    getline(fileVar, temp);
    return temp;
} 


void initalize(string location, ifstream & fileVar) {
    fileVar.open(location);

    if (!fileVar) {
        cout << "ERROR! " << location << " failed to open!";
        exit(1);
    }
}


//Ideally, the input file should be JSON, YAML, or TOML based 
//instead of pure plain text for ease of human access
//but C++ doesn't have JSON parsing library in std for some reason
vector<Orderable> encodeOrderables(ifstream & fileVar) {
    string temp;
    vector<Orderable> orderablesFromFile;
    while(fileVar.peek() != EOF) {
        //Here's something absolutely nasty that I discovered while working on this:
        //when attempting to write the line
        //orderablesFromFile.push_back(Orderable(readline(fileVar)), stod(readline(fileVar)));
        //with the object's constructor taking the name then price parameter, I found out that
        //constructors are executed from right-to-left, not left-to-right and the price would be
        //read first rather than the name.
        //
        //This might be the case for all functions, I did not check.
        //
        //There is literally no good reason for this to be the case.
        orderablesFromFile.push_back(Orderable(stod(readline(fileVar)), readline(fileVar)));
    }
    return orderablesFromFile;
}

//Menu systems
//Wish we could do some ncurses TUI menus, but alas we're stuck with subpar prompts

int catagoryMenu() {
    int choice;
    //No input validation here since the rubric doesn't call for it.
    cout << "Pick a catagory\n";
    cout << "1. Drink\n";
    cout << "2. Appetizer\n";
    cout << "3. Entree\n";
    cout << "4. Dessert\n";
    cout << "5. Finish Order\n";
    cout << "Enter Selection: ";
    cin >> choice;
    return choice;
}

foodOrder orderingMenu(vector<Orderable> items) {
    foodOrder completeOrder;
    int choice;
    for(int itemPos = 0; itemPos < items.size(); itemPos++) {
        cout << itemPos << ". " << items[itemPos].get_name() << " - $" << items[itemPos].get_price() << endl;
    }
    cout << "Enter Selection: ";
    cin >> choice;
    cout << "Enter Amount Desired: ";
    cin >> completeOrder.quantity;

    completeOrder.name = items[choice].get_name();
    completeOrder.price = items[choice].get_price();

    //"...you will need to record the item name, price and the quantity desired inside of variables (vector or array) for output later..."
    //I am modifying this instruction a bit to use a struct instead since structs can hold multiple datatypes and play nice with functions
    return completeOrder;
}

//Who can afford to pay this much when tipping? 
//I can barely afford car insurance!
double tip() {
    int choice;
    //No input validation here since the rubric doesn't call for it.
    cout << "What percent would you like to tip?\n";
    cout << "1. 18%\n";
    cout << "2. 20%.\n";
    cout << "3. 25%.\n";
    cout << "4. Custom Amount.\n";
    cin >> choice;
    switch(choice) {
        case 1:
            return 0.18;
            break;
        case 2:
            return 0.20;
            break;
        case 3:
            return 0.25;
            break;
        case 4:
            double tip;
            cout << "Enter a tip amount (decimal notation) [ex: 0.18]: ";
            cin >> tip;
            //Evil solution to evil users
            return abs(tip);
            break;
        default:
            cout << "ERROR: Your input was invalid, terminating";
            exit(1);

    }
    return choice;

}

double figureTotal(vector<foodOrder> orderList) {
    double subtotal;
    for(int orderPos = 0; orderPos < orderList.size(); orderPos++) {
        subtotal = subtotal + orderList[orderPos].price;
    }
    double tax = subtotal*0.1;
    double total = subtotal+tax;

    //tips
    cout << "===Amount Currently Due==\n";
    cout << "Subtotal: $" << subtotal << endl;
    cout << "Tax: $" << tax << endl;
    cout << "Total: $" << total << endl;
    cout << "=========================\n";


    total = total + (total*tip());
    
    cout << "\033[2J\033[1;1H";
    
    cout << "===Amount Currently Due==\n";
    cout << "Subtotal: $" << subtotal << endl;
    cout << "Tax: $" << tax << endl;
    cout << "Total: $" << total << endl;

    return total;
}

void collectDues(double amountDue) {
    double paid;
    while (amountDue > 0) {
        cout << "Please pay for the amount owed: $" << amountDue << endl;
        cout << "Enter payment: ";
        cin >> paid;
        amountDue = amountDue - paid;
        paid = 0;
    }
}

int main() {
    //File Vars & Inits
    ifstream drinkFile;
    ifstream appetizerFile;
    ifstream entreeFile;
    ifstream dessertFile;

    initalize("drink.txt", drinkFile);
    initalize("appetizer.txt", appetizerFile);
    initalize("entree.txt", entreeFile);
    initalize("dessert.txt", dessertFile);

    //Ordering Vars
    vector<Orderable> possibleDrinks = encodeOrderables(drinkFile);
    vector<Orderable> possibleAppetizer = encodeOrderables(appetizerFile);
    vector<Orderable> possibleEntree = encodeOrderables(entreeFile);
    vector<Orderable> possibleDessert = encodeOrderables(dessertFile);
    
    vector<foodOrder> userOrderList;
    bool ordering = true;

    //"The customer should be able to remain in a category menu until they are ready to return to the main menu"
    //I assume this means that the customer should be allows to keep ordering until they're satisfied
    while(ordering) {
    switch(catagoryMenu()) {
        case 1:
            userOrderList.push_back(orderingMenu(possibleDrinks));
            break;
        case 2:
            userOrderList.push_back(orderingMenu(possibleAppetizer));
            break;
        case 3:
            userOrderList.push_back(orderingMenu(possibleEntree));
            break;
        case 4:
            userOrderList.push_back(orderingMenu(possibleDessert));
            break;
        case 5:
            ordering = false;
            break;
        default:
            cout << "ERROR: Your input was invalid, terminating";
            exit(1);
    }

    }
    collectDues(figureTotal(userOrderList));
    //When the customer is finished ordering, display the subtotal, tax, and total on the screen
    //Ask for a tip (make a suggested tip amount with 18%, 20%, 25%), then update the total with the tip amount entered
    //Get payment from the user and display change due to the customer
    //If the customer does not pay enough money, then the program should continue to ask for money until the total is paid in full

}

/*
   This program is free software: you can redistribute it and/or modify it under the terms of the GNU Affero General Public License Version 3 ONLY as published by the Free Software Foundation.

   This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Affero General Public License for more details.

   You should have received a copy of the GNU Affero General Public License along with this program.  If not, see <https://www.gnu.org/licenses/>.
   */