#include <iostream>
#include <memory>
#include <list>
#include <string>
#include <thread>
#include <cstdio>
#include <random>
#include <philosopher.hpp>

class Philosopher;

void
findNumberOfPhilosophersInParams(const int argc, char **argv, int *const numberOfPhilosophers);

int
main(int argc, char **argv) {
    // std::shared_ptr<std::vector<std::shared_ptr<Philosopher>>
    ListOfPhilosophersPtr philosophers(new ListOfPhilosophers());
    // Default value for the number of dining philosophers.
    int numberOfPhilosophers = 5;
    // Attempts to find a tailored value provided by the user for numberOfPhilosophers.
    findNumberOfPhilosophersInParams(argc, argv, &numberOfPhilosophers);
    printf("%d philosophers to create.\n", numberOfPhilosophers);
    // Pushes a number of philosophers equal to numberOfPhilosophers to the table.
    for (int i = 0; i < numberOfPhilosophers; i++) {
        printf("Creating philosopher: %d.\n", i);
        philosophers->push_back(PhilosopherPtr(new Philosopher(philosophers, i)));
    }
    // If the jthreads go out of scope is equal than joining, which is undersirable on the
    // insides of a for loop if we want they to execute in parallel.
    std::vector<std::jthread> threads;
    for (unsigned long int i = 0; i < philosophers->size(); i++) {
        // A pitfall would be to use here i directly since it would be incremented before
        // it is used by jthread, so a pointer is needed.
        std::shared_ptr<unsigned long> numberOfPhilosopher(new unsigned long());
        *numberOfPhilosopher = i;
        threads.push_back(std::jthread([philosophers, numberOfPhilosopher] {
            // This starts the dinner for the philosopher *numberOfPhilosopher.
            // While philosophers are yet not dinning the state for them is thinking
            // anyway, so they have to problem with the neighbors dining already.
            (*philosophers)[*numberOfPhilosopher]->startThread(); 
        } ));
    }
}

/*
 * Checks if the parameter list is greater or equal than 2 and takes the second parameter.-
 * The first if ignoring the current executable name.- And with this parameter attempts to
 * get a number to be used as the number of philosophers in the table.
 *
 * In case of failure, numberOfPhilosophers is not changed, else is set to the integer value
 * of the parameter.
 */
void
findNumberOfPhilosophersInParams(const int argc, char **argv, int *const numberOfPhilosophers) {
    // The user did not gave us enough arguments, early return.
    if (argc < 2) {
        return;
    }
    // numberOfPhilosophersAsString is now equal to the supposed number the user gave us.
    const char *numberOfPhilosophersAsString = argv[1];
    try {
        // Converts param to number, can throw an exception.
        *numberOfPhilosophers = std::stoi(numberOfPhilosophersAsString, NULL, 10);
    } catch (std::exception &ex) {
        printf("The number of philosophers is not a valid number, continuing\n");
    }
}