#include <stdbool.h>
#include <stdlib.h>
#include <unistd.h>
#include <time.h>
#include "adder.h"
#include "mailbox.h"

/**
 * Read all of the values from the given mailbox id and then send it back to mailbox 0.
 *
 * @param raw_mailbox_id A ponter to an integer holding the mailbox id this thread should read from.
 * @return void* Returns a pointer to a return code. -1 on error, 0 otherwise. Must be freed by caller.
 */
void *adder(void *raw_mailbox_id) {
	int mailbox_id = *(int*)(raw_mailbox_id);
	// If we're thread 0, we shouldn't be running adder.
	// Any thread id below 0 is invalid.
	if (mailbox_id <= 0) {
		int *ret_val = malloc(sizeof(int));
		*ret_val = -1;
		return ret_val;
	}

	int num_messages = 0;
	int total_value = 0;
	int start_time = time(NULL);
	struct msg message;
	while (true) {
		int recv_result = RecvMsg(mailbox_id, &message);
		if (recv_result != 0) {
			int *ret_val = malloc(sizeof(int));
			*ret_val = -1;
			return ret_val;
		}

		// If we have a negative value, we're done receiving messages.
		if (message.value < 0) {
			break;
		}

		num_messages++;
		total_value += message.value;
		sleep(1);
	}

	int end_time = time(NULL);
	struct msg res_mesage = {
		.iFrom = mailbox_id,
		.value = total_value,
		.cnt = num_messages,
		.tot = end_time - start_time,
	};

	int send_result = SendMsg(0, &res_mesage);
	if (send_result < 0) {
		int *ret_val = malloc(sizeof(int));
		*ret_val = -1;
		return ret_val;
	}

	int *ret_val = malloc(sizeof(int));
	*ret_val = 0;
	return ret_val;
}