// router.h

#ifndef WN_ROUTE_H
#define WN_ROUTE_H

#include <stdlib.h>

typedef enum {
    GET,
    POST,
    PUT,
    DELETE,
} wn_method;

typedef struct {
    wn_method method;
    char *path;
} wn_context;

typedef void (*wn_handler)(wn_context *);

typedef struct {
    wn_method method;
    char *regex;
    wn_handler handler;
} wn_route;

wn_handler wn_get_handler(wn_method method, char *path,
                          wn_route *routes, size_t routes_len);

#endif

// router.c

#include <regex.h>

wn_handler wn_get_handler(wn_method method, char *path,
                          wn_route *routes, size_t routes_len) {
    int err;
    regex_t regex;
    regcomp(&regex, "^$", 0); // Make the first regfree call work without UB.

    for (size_t i = 0; i < routes_len; ++i) {
        if (routes[i].method != method) continue;

        regfree(&regex);
        err = regcomp(&regex, routes[i].regex, 0);
        if (err > 0) continue; // fuck this shit

        int match = regexec(&regex, path, 0, NULL, 0);
        switch (match) {
            case 0:
                regfree(&regex);
                return routes[i].handler;
            case REG_NOMATCH: continue;
            default: continue; // fuck this shit
        }
    }

    regfree(&regex);
    return NULL;
}