#include <cstring>

#include <evhtp.h>

#include <stdio.h>

#include <thread>

// No error checking or anything of the sort, as per the guidelines

const int num_threads = -1;

void on_request_index(evhtp_request_t *req, void *) {

if (req->method == htp_method_GET) {

evhtp_send_reply(req, EVHTP_RES_OK);

} else

evhtp_send_reply(req, EVHTP_RES_400);

}

void on_request_user_register(evhtp_request_t *req, void *) {

if (req->method == htp_method_POST) {

evhtp_send_reply(req, EVHTP_RES_OK);

} else

evhtp_send_reply(req, EVHTP_RES_400);

}

void on_request_user_index(evhtp_request_t *req, void *) {

if (req->method == htp_method_GET) {

const char *p = req->uri->path->match_start;

const unsigned int pl = strlen(p);

evbuffer_add_reference(req->buffer_out, p, pl, NULL, NULL);

evhtp_send_reply(req, EVHTP_RES_OK);

} else

evhtp_send_reply(req, EVHTP_RES_400);

}

int main(int argc, char **argv) {

evbase_t *evbase = event_base_new();

evhtp_t *htp = evhtp_new(evbase, NULL);

evhtp_set_parser_flags(htp, EVHTP_PARSE_QUERY_FLAG_LENIENT);

evhtp_enable_flag(htp, EVHTP_FLAG_ENABLE_NODELAY);

evhtp_set_regex_cb(htp, "^/user/([^/]+)", on_request_user_index, NULL);

evhtp_set_cb(htp, "/user", on_request_user_register, NULL);

evhtp_set_cb(htp, "/", on_request_index, NULL);

evhtp_bind_socket(htp, "0.0.0.0", 3000, 1024);

if (num_threads > 1) {

evhtp_use_threads_wexit(htp, NULL, NULL, num_threads, NULL);

} else if (num_threads < 0) {

const int cores = std::thread::hardware_concurrency();

if (cores > 0 && cores > -num_threads) {

evhtp_use_threads_wexit(htp, NULL, NULL, cores + num_threads, NULL);

}

}

event_base_loop(evbase, 0);

return 0;

}