Documentation added

Park_time.cpp

@@ -1,5 +1,13 @@
 #include "headers/Park_time.h"
 
+/*
+initializes everything, id is auto incremented from what's stored in the db.
+inmediately saves to db upon creation.
+Also, this weird syntax is called an initializer list, and is the preffered
+method of how to initialize members. It has a measurable performance increase
+because it uses move semantics instead of copy semantics.
+https://www.geeksforgeeks.org/when-do-we-use-initializer-list-in-c/
+ */
 Park_time::Park_time(int c_id, int s_id)
     : customer_id{c_id},
       spot_id{s_id},
@@ -8,7 +16,9 @@ Park_time::Park_time(int c_id, int s_id)
       id{auto_increment_db() + 1} {
     save_db();
 }
-
+/*
+this one initializes with data from the database. should probably only be used in the query functions.
+ */
 Park_time::Park_time(int id_, int customer_id_, int spot_id_, int start_,
                      int duration_)
     : id{id_},
@@ -19,7 +29,12 @@ Park_time::Park_time(int id_, int customer_id_, int spot_id_, int start_,
     end = time_point<system_clock>(seconds(start_ + duration_));
 }
 
+/*
+simple checking if customer is clocking out at the right spot.
+sets end(time of clocking out) and calculates the duration.
+updates the info in the database.
 
+ */
 void Park_time::clock_out(int c_id, int s_id) {
 
     if (c_id != customer_id) {
@@ -52,7 +67,8 @@ std::ostream& operator<<(std::ostream& os, const Park_time& pt) {
     os << "- - - - - - - - - - - - - - - - - - - -\n";
     return os;
 }
-
+// mostly a helper function to ease the conversion from timepoint to int
+// for storing in the db
 int Park_time::start_to_int() {
     auto start_to_epoch = start.time_since_epoch();
     auto start_value = duration_cast<seconds>(start_to_epoch);
@@ -64,6 +80,9 @@ int Park_time::start_to_int() {
 // -----------------------------------------------------------------------------
 
 void Park_time::save_db() {
+    /*
+    this creates a sql statement and then executes it
+     */
     string statement{"insert into Park_time values ( , , , , , );"};
     statement.insert(41, "NULL");
     statement.insert(39, "NULL");
@@ -75,7 +94,7 @@ void Park_time::save_db() {
     data::db.exec(statement);
     transaction.commit();
 }
-
+// same as above
 void Park_time::update_db() {
     string statement =
         "UPDATE Park_time SET end = , duration =  where id = '';";

Query.cpp

@@ -78,8 +78,10 @@ Customer query_customer_with_id(int id) {
 
 // -------------- paroking spots
 
-// vector<Park_spot>  query_all_parking_spots() {
-//     vector<Park_spot> spots;
+
+
+// vector<Park_spot> populate_spots(){
+//         vector<Park_spot> spots;
 //     SQLite::Statement query(data::db, "SELECT * FROM Park_spot WHERE id > 0;");
 //     // query.bind(1, 2);
 //     while (query.executeStep()) {
@@ -91,19 +93,3 @@ Customer query_customer_with_id(int id) {
 //     }
 //     return spots;
 // }
-
-
-
-vector<Park_spot> populate_spots(){
-        vector<Park_spot> spots;
-    SQLite::Statement query(data::db, "SELECT * FROM Park_spot WHERE id > 0;");
-    // query.bind(1, 2);
-    while (query.executeStep()) {
-        int id = query.getColumn(0);
-        int taken = query.getColumn(1);
-        int cid = query.getColumn(2);
-        // park_customers.push_back(query_customer_with_id(cid));
-        spots.push_back({id, taken, cid});
-    }
-    return spots;
-}

data.cpp

@@ -3,15 +3,25 @@
 namespace data {
 
 SQLite::Database start_db() {
+    /*
+    Opens the database, creates it if it can't find the file.
+     */
     SQLite::Database db("test.db3",
                         SQLite::OPEN_READWRITE | SQLite::OPEN_CREATE);
     while (sodium_init() < 0) {
         std::cout << "SODIUM NOT WORKING";
+        /*
+        This shouldn't be here, really, but I can't think of a better place
+        where it runs at least once. This seeds the random generator needed for
+        salts and other stuff, and needs to be run at least once when working
+        with any libsodium function.
+         */
     }
-
+    //sql syntax is surprisingly readable.
     db.exec(
         "create table if not exists Customer (id integer primary key, name "
         "text, password text, verhicle int)");
+        // getting errors when using bool, so i used an int instead.
     db.exec(
         "create table if not exists Park_spot (id integer primary key, taken "
         "int, customer_id int)");

encrypt.cpp

@@ -1,16 +1,19 @@
 #include "headers/encrypt.h"
 
-
 string hash_password(string password) {
     /*
     Passing strings and converting to char* because I do not want to be forced
     to use char * whenever I want to call the function. Low level stuff in the
     function, the least possible low level stuff outside.
+    This uses the password hashing algorithm Argon2 implemented by libsodium.
+    DO NOT MODIFY memory_limit and cpu_limit after you add customers to the db.
+    When you do that, the hashed passwords can't be decrypted, and that would be
+    BAD
      */
     const char* password_ = password.c_str();
     char hashed_password_[crypto_pwhash_STRBYTES];
     int memory_limit = 3.2e+7; // 3.2e7 = 32e6 = 32 mb
-    int cpu_limit = 1;          // this is n_threads
+    int cpu_limit = 1;         // this is n_threads
 
     int result = crypto_pwhash_str(hashed_password_,
                                    password_,
@@ -23,6 +26,9 @@ string hash_password(string password) {
 }
 
 bool verify_password(string hashed_password, string unhashed_password) {
+    /*
+    this verifies the password. It's encryption magic and don't question it.
+     */
     const char* password_ = unhashed_password.c_str();
     const char* hashed_password_ = hashed_password.c_str();
 

headers/Customer.h

@@ -9,17 +9,29 @@
 
 using std::vector;
 
-// will make it easy to represent it in the database while making it easy to use
-// while programming
+/*
+enum classes make it easy to represent categories.
+So you can use something like Verhicle_type::car instead of 2. but under the
+hood, it's still an int. This is here so you won't have to have global variables
+for these categories, or worse, use magic numbers in the code.
+
+ */
 enum class Verhicle_type { bike = 1, small_car = 2, suv = 3, pickup = 4 };
 
 /*
-card code is een randomly generated string moeten zijn, die je bv. op een nfc
-card zou opslaan en zo zou authenticaten bij je parking spot. We kunnen dit ipv
-of samen met een password gebruiken. clock in en out creeert en compleet een
-park_time object. Voegt het toe aan een vector.
+Customer constructors do the same stuff as all the other constructors.
+clock_in and out create and modify park_time objects and store them to
+park_instances. Technically, now that we have a working db, we don't need it.
+TODO: fix this.
 
-*/
+gen_monthly just prints out all the park_time objects in park_instances.
+It should (and can safely) be removed, but it's here as a quick example of
+report generation It has no logic to speak of that only generates report of
+ptime objects of this month.
+TODO: remove when have seperate report generation functions.
+
+save, update, delete and auto increment are the same as in park_time.
+ */
 
 class Customer {
   public:
@@ -27,9 +39,7 @@ class Customer {
     string name;
     string password;
     Customer(string name_, string password_, Verhicle_type verhicle_);
-    Customer(int id_, string name_, // needed to construct from db
-             string password_,
-             Verhicle_type verhicle_, // TODO: how init. p_time instances?
+    Customer(int id_, string name_, string password_, Verhicle_type verhicle_,
              vector<Park_time> instances);
     void clock_in(int s_id);
     void clock_out(int s_id);
@@ -37,7 +47,7 @@ class Customer {
     void update_db();
     void delete_db();
 
-    void gen_monthly(); // remove, make it a function in data
+    void gen_monthly();
     Verhicle_type verhicle;
 
   private:
@@ -46,5 +56,4 @@ class Customer {
     int auto_increment_db();
 };
 
-
 #endif // CUSTOMER_H

headers/Park_time.h

@@ -17,6 +17,28 @@ using std::to_string;
 
 
 Record of who parked at what park_spot and at what time.
+public interface-------------------------------------------
+
+The constructors. one for creating new customers, the other one used by the
+query functions to construct the object from information stored in the database.
+
+clock_out is the function that gets called from customer.clock_out().
+It verifies that the customer is clocking out at the correct parkspot, and saves
+the current time of clocking out in end. It also calculates duration so it
+doesn't have to be calculated more than once.
+
+operator<< is << overload, can(should) be used for report generation.
+
+
+// implementation stuff------------------------
+start and end are time points representing when someone clocks in and out. they're from the chrono namespace.
+
+save and update save and update info in the database.
+auto_increment pulls the highest id stored in the db, to be used in the constructor.
+
+start_to_int() is used to convert the start timepoint to an integer that can be saved in the database
+SQL datetime and chrono datetime don't seem the most compatible.
+
 */
 
 class Park_time {

headers/Query.h

@@ -4,17 +4,57 @@
 
 #include "Park_spot.h"
 
-#include <array>
+/*these are the functions that search the database and create objects from it.
+
+query_parktimes_for_customer searches for the parktimes  that are needed in
+customer initialisaiton. generally, i see no use outside of that.
+
+query_customer_with_name searches for customer data by name.
+
+query_customer_with_id does what the above does, but with id.
+
+
+populate_spots is used to query for all the park_spots and return them as
+objects.
+
+The design desision to use vector<T> instead of <T> is for the following
+reasons:
+
+1. some of these can potentially return more than one object. For example, 2
+customers who have the same name.
+
+2. I have no clue how many of you have done error handling in c++
+(try/catch/finally).
+Ya boi is nice and doesn't want to bombard you with more new concepts than needed.
+so now you'd do 
+
+vector<Customer> test = query_customer_with_name("Testman");
+
+if (!test.size()) {print no customers found, do stuff}
+else if (test.size() > 1) { do stuff to get the right one if you only need one
+}
+
+instead of 
+try {
+    customer test = query_customer_with_name("Testman");
+}
+catch(someException.probablycalled_not_found) {do_Stuff};
+catch(...) {
+    do stuff
+}
+finally{
+    do more stuff
+}
+
+3. Ya boi needs to brush up on how to create custom exceptions class, and it will complicate code furhter.
+
+ */
 
 vector<Park_time> query_parktimes_for_customer(int cid);
 
 vector<Customer> query_customer_with_name(string name);
 Customer query_customer_with_id(int id);
 
-// vector<Park_spot> query_all_parking_spots(); // used for initializing the parking spots at start of the program
 vector<Park_spot> populate_spots();
 
-
-
-
 #endif // CUSTOMER_H

headers/data.h

@@ -5,8 +5,13 @@
 #include "encrypt.h"
 
 namespace data {
-SQLite::Database start_db();
 
+/*
+start_db is the function that opens the database, and
+if the necesary tables are not there, creates them. 
+db is the database, and is static to avoid multiple redefinition errors. 
+ */
+SQLite::Database start_db();
 static SQLite::Database db = start_db();
 
 } // namespace data

headers/encrypt.h

@@ -2,12 +2,20 @@
 #define ENCRYPT_H
 #pragma once
 
-#include <string>
 #include <cstring>
-#include <sodium.h>
 #include <iostream>
+#include <sodium.h>
+#include <string>
 
 using std::string;
+/*
+hash_password takes the password, and encrypts it. This needs to be done,
+because storing passwords in plaintext is BAD! 
+
+verify_password takes in a password and the hashed password, and then does magic encryption stuff(no, not
+really. It basically hashes the password with the same salt and other
+parameters) and to see if the password stored and the given password match.
+ */
 
 string hash_password(string password);
 bool verify_password(string hashed_password, string unhashed_password);

main.cpp

@@ -1,65 +1,103 @@
 #include "headers/Query.h"
 
-#include <chrono>
 #include <thread>
 
 
 using namespace std::chrono;
 
 /*
-Code strucure like this:
-class declarations zijn in /headers/class_naam.h, en definitions van de member
-functs in /class_naam.cpp elke klas in zn eigen file omdat ik incomplete class
-declarations wilt tegengaan, omdat ik ze niet goed begrijp. En header/source
-split om multiple definition errors tegen te gaan.
+Code structure is like this:
+1. encrypt.cpp en /header/encrypt.h contain functions to hash passwords and
+verify passwords
 
-Park_spot representeert een parkeermeter bij elke parkeer spot.
-Een customer is een customer.
-Park time is een object die reffereert naar parkspot en customer, basically een
-record die zegt dat een customer voor x tijd geparkeert heeft bij spot x, enz.
+2. data.cpp and /header/data.h contain the code to start up the database.
+Originally, they were supposed to contain all the functions to save to the
+database and query from the database. I had trouble doing that, (cyclical
+includes) and some other issues. the other issues are gone due to the latest
+refactor, but to make it like my original plan is going to take a few hours, and
+I have done too much already to want to do more work unless needed.
+The functions to save to a database have been integrated in the classes
+themself, and unless issues arrise from that I'm not changing that. Functions to
+get objects from the database are in Query.cpp en header.
 
-De client clockt in en uit bij een spot.
+3. Park_time.cpp en header.
+Contain the implementation details of Park_time, which is basically a record of
+who parked at what spot and when. Uses a mix of ctime and chrono functions to do
+most of the stuff, it's a mess. I will probably have to commit to Doing it one
+way or the other to make it more comperhensible, especially for whoever will
+make report functions.
+
+4. Customer.cpp and header.
+Contains the implementation of Customer. Customer represents a customer, and
+saves park_time instances in itself. Not much to explain.
+
+5. Park_spot.cpp and header.
+It contians the implementation details of Park_spot, which represents it's
+namesake.
+
+6. Query.cpp and header.
+Cointain functions that search the database and return objects(P_time, P_spot,
+Customer) It is the least tested of the whole project, use with care.
+
+Explanation of what members do of P_time, P_spot, Customer are in the respective
+headers. Explanations of how the member functions work(Or how I intended for
+them to work) are in the respective .cpp files. void Wait(int sec)
  */
 
 void Wait(int sec)
-/*
-a wait function where 1 sec represents 1 hour irl.
- */
+
 {
+    /*
+a wait function where 1 sec represents 1 hour irl. It has been used for testing
+purposes mostly.
+TODO: Needs to be removed at completion of project, or seperated in a test
+cpp/header
+ */
     std::this_thread::sleep_for(seconds{sec});
 }
 
-static vector<Park_spot> parking_spots = populate_spots(); // to save the parking spots in memory
-static vector<Customer> park_customers; // save the customers that are parked in here
+static vector<Park_spot> parking_spots = populate_spots();
+// this queries the db for all the saved parking_spots and initializes them
+
+static vector<Customer> park_customers;
+/*
+This was meant for an older implementation. park_time objects used to store
+pointers to customers and in order to not get dangling pointers(dangerous!) I
+had to have a way to store the customers the pointer pointed to so they didn't
+get destroyed prematurely(I could've used the lower-level, more dangerous new,
+or worse, malloc, but that's ugly).
+For now, it's just here in case you want an easy way to store customers.
+ */
 
 int main() {
     Customer sagar = query_customer_with_name("stefan udit")[0];
     Customer sagar1 = query_customer_with_id(2);
-    cout << sagar.id << "," << sagar.name << "," << sagar.password<< "\n";
+    cout << sagar.id << "," << sagar.name << "," << sagar.password << "\n";
     cout << sagar1.id << "," << sagar1.name << "," << sagar1.password;
     cout << parking_spots.size();
 
-    for (auto i : parking_spots){
+    for (auto i : parking_spots) {
         cout << "\n" << i.id << "," << i.parked_customer;
     }
 
     populate_spots();
-
 }
 
-
-
-
-// vector<Park_spot> populate_spots(){
-//         vector<Park_spot> spots;
-//     SQLite::Statement query(data::db, "SELECT * FROM Park_spot WHERE id > 0;");
-//     // query.bind(1, 2);
-//     while (query.executeStep()) {
-//         int id = query.getColumn(0);
-//         int taken = query.getColumn(1);
-//         int cid = query.getColumn(2);
-//         // park_customers.push_back(query_customer_with_id(cid));
-//         spots.push_back({id, taken, cid});
-//     }
-//     return spots;
-// }
+/*
+Why is this not in query.cpp? Because somehow, it errors out when it's there.
+The error message indicates it is a memory issue but I suspect it's a
+concurrency issue. Do not move this.
+ */
+vector<Park_spot> populate_spots() {
+    vector<Park_spot> spots;
+    SQLite::Statement query(data::db, "SELECT * FROM Park_spot WHERE id > 0;");
+    // query.bind(1, 2);
+    while (query.executeStep()) {
+        int id = query.getColumn(0);
+        int taken = query.getColumn(1);
+        int cid = query.getColumn(2);
+        // park_customers.push_back(query_customer_with_id(cid));
+        spots.push_back({id, taken, cid});
+    }
+    return spots;
+}