Data update

Task/Simple-database/11l/simple-database.11l

@@ -1,11 +1,4 @@
-T Item
-   String name, date, category
-
-   F (name, date, category)
-      .name = name
-      .date = date
-      .category = category
-
+T Item((String name, String date, String category))
    F String()
       R .name‘, ’(.date)‘, ’(.category)
 

Task/Simple-database/C++/simple-database.cpp

@@ -0,0 +1,147 @@
+#include <algorithm>
+#include <cstdint>
+#include <fstream>
+#include <iostream>
+#include <limits>
+#include <string>
+#include <vector>
+
+const std::string filename = "Contacts.dat";
+
+class Contact {
+public:
+	Contact(const std::string& aName, const std::string& aBirth_Date, const std::string& aState,
+			const std::string& aRelation, const std::string& aEmail)
+	: name(aName), birth_date(aBirth_Date), state(aState), relation(aRelation), email(aEmail) { }
+
+	std::string get_relation() const {
+		return relation;
+	}
+
+	std::string to_string() const {
+		return name + ", " + birth_date + ", " + state + ", " + relation + ", " + email;
+	}
+
+	bool operator<(const Contact& other) const {
+		return birth_date > other.birth_date;
+	}
+
+private:
+	std::string name, birth_date, state, relation, email;
+};
+
+std::vector<Contact> contacts = { };
+
+Contact parse(std::string entry) {
+	std::vector<std::string> parts;
+	uint64_t position = 0;
+	while ( ( position = entry.find(", ") ) != std::string::npos ) {
+		parts.emplace_back(entry.substr(0, position));
+		entry.erase(0, position + 2);
+	}
+	return Contact(parts[0], parts[1], parts[2], parts[3], entry);
+}
+
+void write_file(const std::string& new_entry) {
+	std::fstream database(filename, std::ios::out | std::ios::app);
+	if ( database.is_open() ) {
+		database << new_entry;
+		database.close();
+	} else {
+		std::cerr << "Unable to open database '" << filename << "' for writing" << std::endl;
+	}
+}
+
+// Open the file if it exists, otherwise create a new empty file.
+void read_file() {
+	std::fstream database(filename, std::ios::in | std::ios::app);
+	if ( database.is_open() ) {
+		std::string entry;
+		while ( std::getline(database, entry) ) {
+			contacts.emplace_back(parse(entry));
+		}
+		database.close();
+	} else {
+		std::cerr << "Unable to open database '" << filename << "' for reading" << std::endl;
+	}
+}
+
+void add_new_entry() {
+	std::cout << "Type the new entry, without inverted commas, in the format:" << std::endl;
+	std::cout << "Name, Birth_Date, State, Relation, Email" << std::endl;
+	std::string new_entry;
+	std::cin.ignore(std::numeric_limits<std::streamsize>::max(), '\n'); // Clear the keyboard buffer
+	std::getline(std::cin, new_entry);
+	Contact contact(parse(new_entry));
+	contacts.emplace_back(contact);
+	write_file(new_entry);
+	std::cout << "The contact \"" << new_entry << "\" has been added to the database" << std::endl;
+}
+
+void show_latest_entry() {
+	if ( ! contacts.empty() ) {
+		std::cout << "The latest entry is: " + contacts.back().to_string() << std::endl;
+	} else {
+		std::cout << "There are currently no entries in the database" << std::endl;
+	}
+}
+
+void show_latest_special_entry(const std::string& search) {
+	int32_t index = contacts.size() - 1;
+	while ( index >= 0 && contacts[index].get_relation() != search ) {
+		index--;
+	}
+
+	if ( index >= 0 ) {
+		std::cout << "The latest " << search << " entry is " + contacts[index].to_string() << std::endl;
+	} else {
+		std::cout << "There are currently no " << search << " entries" << std::endl;
+	}
+}
+
+void show_latest_friend_entry() {
+	show_latest_special_entry("Friend");
+}
+
+void show_latest_family_entry() {
+	show_latest_special_entry("Family");
+}
+
+void list_all_entries_by_age() {
+	if ( ! contacts.empty() ) {
+		std::vector<Contact> copy_contacts = contacts;
+		std::sort(copy_contacts.begin(), copy_contacts.end());
+		for ( const Contact& contact : copy_contacts ) {
+			std::cout << contact.to_string() << std::endl;
+		}
+	} else {
+		std::cout << "There are currently no entries in the database" << std::endl;
+	}
+}
+
+int main() {
+	read_file();
+	uint32_t choice = 0;
+	while ( choice != 6 ) {
+		std::cout << std::endl;
+		std::cout << "            Menu            " << std::endl;
+		std::cout << " 1: Add a new entry" << std::endl;
+		std::cout << " 2: Show latest entry" << std::endl;
+		std::cout << " 3: Show latest Friend entry" << std::endl;
+		std::cout << " 4: Show latest Family entry" << std::endl;
+		std::cout << " 5: List all entries by age" << std::endl;
+		std::cout << " 6: Close the program" << std::endl;
+		std::cout << std::endl;
+
+		std::cin >> choice;
+		switch ( choice ) {
+			case 1 : add_new_entry(); break;
+			case 2 : show_latest_entry(); break;
+			case 3 : show_latest_friend_entry(); break;
+			case 4 : show_latest_family_entry(); break;
+			case 5 : list_all_entries_by_age(); break;
+			case 6 : std::cout << "Program closed" << std::endl; break;
+			default : std::cout << "Please enter a number in the range 1..6" << std::endl; break;
+		}
+	}
+}