/* As of FreeBSD 13.2, sigaction(2) still conforms to IEEE Std
 * 1003.1-1990 (POSIX.1), which did not define SA_RESTART.
 * FreeBSD supports it as an extension, but then _POSIX_C_SOURCE must
 * not be defined. */
#ifndef __FreeBSD__
#define _POSIX_C_SOURCE 200809L
#endif

#include <dynstr.h>
#include <libweb/handler.h>
#include <libweb/html.h>
#include <libweb/http.h>
#include <errno.h>
#include <signal.h>
#include <stddef.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>

static const size_t max_headers = 5;

static int hello(const struct http_payload *const pl,
    struct http_response *const r, void *const user)
{
    printf("Got %zu headers from the client (max %zu).\n",
        pl->n_headers, max_headers);

    for (size_t i = 0; i < pl->n_headers; i++)
    {
        const struct http_header *const h = &pl->headers[i];

        printf("%s: %s\n", h->header, h->value);
    }

    *r = (const struct http_response)
    {
        .status = HTTP_STATUS_OK
    };

    return 0;
}

static int on_length(const unsigned long long len,
    const struct http_cookie *const c, struct http_response *const r,
    void *const user)
{
    *r = (const struct http_response)
    {
        .status = HTTP_STATUS_FORBIDDEN
    };

    return 1;
}

struct handler *handler;

static void handle_signal(const int signum)
{
    switch (signum)
    {
        case SIGINT:
            /* Fall through. */
        case SIGTERM:
            handler_notify_close(handler);
            break;

        default:
            break;
    }
}

static int init_signals(void)
{
    struct sigaction sa =
    {
        .sa_handler = handle_signal,
        .sa_flags = SA_RESTART
    };

    sigemptyset(&sa.sa_mask);

    static const struct signal
    {
        int signal;
        const char *name;
    } signals[] =
    {
        {.signal = SIGINT, .name = "SIGINT"},
        {.signal = SIGTERM, .name = "SIGTERM"},
        {.signal = SIGPIPE, .name = "SIGPIPE"}
    };

    for (size_t i = 0; i < sizeof signals / sizeof *signals; i++)
    {
        const struct signal *const s = &signals[i];

        if (sigaction(s->signal, &sa, NULL))
        {
            fprintf(stderr, "%s: sigaction(2) %s: %s\n",
                __func__, s->name, strerror(errno));
            return -1;
        }
    }

    return 0;
}

int main(int argc, char *argv[])
{
    int ret = EXIT_FAILURE;
    const struct handler_cfg cfg =
    {
        .length = on_length,
        .max_headers = max_headers
    };

    static const char *const urls[] = {"/", "/index.html"};

    if (!(handler = handler_alloc(&cfg)))
    {
        fprintf(stderr, "%s: handler_alloc failed\n", __func__);
        goto end;
    }

    for (size_t i = 0; i < sizeof urls / sizeof *urls; i++)
        if (handler_add(handler, urls[i], HTTP_OP_GET, hello, NULL))
        {
            fprintf(stderr, "%s: handler_add failed\n", __func__);
            goto end;
        }

    unsigned short port;

    if (handler_listen(handler, 0, &port))
    {
        fprintf(stderr, "%s: handler_listen failed\n", __func__);
        goto end;
    }

    printf("Listening on port %hu\n", port);

    if (handler_loop(handler))
    {
        fprintf(stderr, "%s: handler_loop failed\n", __func__);
        goto end;
    }

    ret = EXIT_SUCCESS;

end:
    handler_free(handler);
    return ret;
}