main.cpp

#include "main.h"
// MAIN
int main() {
	welcome(); // always print welcome message
	ifstream inFile; // for reading from farms.txt
	FarmList farmList;
	char option;
	if (!openInFile(inFile)) { // atempt to open file
		cout << "Error opening file!! Terminating..." << endl;
		return 1;
	}
	readFromFile(inFile, farmList); // populate farms[] with data and close file
	option = getMenuChoice(); // get the first menu choice(validated)
	while (option != 'q') { // continute menu loop until user enters q for quit
		execCommand(option, farmList);
		option = getMenuChoice();
	}
	ofstream outFile; // for writing to farms.txt
	if (!openOutFile(outFile)) { // attempt to open file
		cout << "Error opening file!! Terminating..." << endl;
		return 1;
	}
	readToFile(farmList, outFile); // copy adjusted arrays to file in same format
	cout << "Writing to Farms.txt..." << endl;
	cout << "Thank you for using the local farm database!" << endl;
	return 0;
}
// function definitions
void welcome() {
	cout << "Welcome!\nThis program will help you manage the local farms." << endl << endl;
}

// this function attempts to open the farms.txt file for reading
bool openInFile(ifstream& inFile) {
	inFile.open("farms.txt");
	if (inFile.fail()) {
		return false;
	}
	return true;
}

// this function reads from inFile to populate the farms[] array, assumed inFile was previously opened. 
void readFromFile(ifstream& inFile, FarmList &farmList) {
	while (inFile.peek() != EOF) { // read until end of file
		Farm tempFarm;
		char tempName[MAX_CHAR];
		char tempLocation[MAX_CHAR];
		int tempRating, tempNumProducts;
		int tempProduct; // changes as go through array, assigned to products[i] using setProductAt(tempProduct, i)
		inFile.getline(tempName, MAX_CHAR, ';');
		tempFarm.setName(tempName);
		inFile.getline(tempLocation, MAX_CHAR, ';');
		tempFarm.setLocation(tempLocation);
		inFile >> tempRating;
		tempFarm.setRating(tempRating);
		inFile.ignore(); // ignore the ';'
		inFile >> tempNumProducts;
		tempFarm.setNumProducts(tempNumProducts);
		inFile.ignore(); // ignore the ';'
		for (int i = 0; i < tempFarm.getNumProducts(); i++) {
			inFile >> tempProduct; // read the product code for that index
			tempFarm.setProductAt(tempProduct, i); // set the product code at index i
			inFile.ignore(); // ignore the ','
		}
		inFile.ignore(10000, '\n');
		farmList.insertFarm(tempFarm); // insert the current farm into the list		
	}
	inFile.close(); // closes inFile at the end of the loop
	cout << "Successfully read from file!" << endl << endl;
}
// this function prints the menu and gets a valid menu choice from the user
char getMenuChoice() {
	char choice;
	cout << MENU << endl;
	cin >> choice;
	while (!cin || (tolower(choice) != 'q' && (tolower(choice) < 'a' || tolower(choice) > 'e'))) {
		cin.clear(); // clear the error flag
		cin.ignore(100, '\n'); // clear input buffer
		cout << "Invalid input!! Please enter a valid option (a-e or q): ";
		cin >> choice;
	}
	cin.ignore(100, '\n'); // ignore excess buffer
	return choice;
}

// this function executes the command based on the menu choice
void execCommand(char option, FarmList &farmList) {
	switch (option) {
	case 'a':
		farmList.addFarm();
		break;
	case 'b':
		farmList.listFarms();
		break;
	case 'c':
		farmList.searchLocation();
		break;
	case 'd':
		farmList.removeByIndex();
		break;
	case 'e':
		farmList.searchByProduct();
		break;
	default:
		exit(1); // option has been previously validated in getMenuChoice(), but if something goes wrong this exits
	}
}

// this function attempts to open the farms.txt file for writing, returns fail if fail to open file
bool openOutFile(ofstream& outFile) {
	outFile.open("farms.txt");
	if (!outFile.is_open()) {
		return false;
	}
	return true;
}

// this function writes the farms[] array to the farms.txt file in the same format as it was read back to farms.txt
void readToFile(FarmList farmList, ofstream& outFile) {
	// assume file was previously opened with openOutFile()
	for (int i = 0; i < farmList.getCount(); i++) { // for each farm
		outFile << farmList.getFarmAt(i).getName() << ";"; // name
		outFile << farmList.getFarmAt(i).getLocation() << ";"; // location
		outFile << farmList.getFarmAt(i).getRating() << ";"; // rating
		outFile << farmList.getFarmAt(i).getNumProducts() << ";"; // numProducts
		for (int j = 0; j < farmList.getFarmAt(i).getNumProducts(); j++) {
			outFile << farmList.getFarmAt(i).getProductAt(j) << ","; // products (seperated by commas)
		}
		outFile << endl; // new line between farm entries
	}
	outFile.close(); // closes the output file
}