/* SPDX-License-Identifier: GPL-3.0-or-later */
/* Copyright 2022 Ivan Polyakov */

#include "servers/tcp.h"
#include "../c/utils.h"
#include <mongoose.h>
#include <signal.h>

/* Handle interrupts, like Ctrl-C */
static int s_signo;
static void signal_handler(int signo)
{
    s_signo = signo;
}

static int mg_str_alloc(char **dest, const struct mg_str str)
{
    *dest = (char *) realloc(*dest, sizeof(char) * (str.len + 1));
    if (!*dest) {
        perror("realloc");
        return 1;
    }
    memcpy(*dest, str.ptr, str.len);
    (*dest)[str.len] = '\0';
    return 0;
}

static int mg_to_rpd_req(rpd_req *req, struct mg_http_message *msg)
{
    char *tmp = NULL;
    if (mg_str_alloc(&tmp, msg->method))
        return 1;
    req->method = rpd_req_smethod(tmp);

    req->body = msg->body.len ? rpd_strdup(msg->body.ptr) : NULL;

    if (mg_str_alloc(&tmp, msg->uri))
        return 1;
    rpd_url_parse(&req->path, tmp);

    rpd_keyval_init(&req->query, 0);
    if (msg->query.len) {
        if (mg_str_alloc(&tmp, msg->query))
            return 1;
        rpd_query_parse(&req->query, tmp);
    }

    size_t i, max = sizeof(msg->headers) / sizeof(msg->headers[0]);
    rpd_keyval_init(&req->headers, max);

    // Iterate over request headers
    char *key = NULL, *val = NULL;
    for (i = 0; i < max && msg->headers[i].name.len > 0; i++) {
        struct mg_str *k = &msg->headers[i].name, *v = &msg->headers[i].value;

        mg_str_alloc(&key, *k);
        mg_str_alloc(&val, *v);

        rpd_keyval_insert(&req->headers, key, val);
    }
    free(key);
    free(val);

    free(tmp);
    return 0;
}

static void handle_request(struct mg_connection *conn, int ev, void *ev_data, void *app)
{
    if (ev == MG_EV_HTTP_MSG) {
        rpd_req *req;
        rpd_res *res;
        char *headers_buff;

        req = (rpd_req *) malloc(sizeof(rpd_req));
        res = (rpd_res *) malloc(sizeof(rpd_res));

        mg_to_rpd_req(req, (struct mg_http_message *) ev_data);
        rpd_res_init(res);

        rpd_app_handle_request((rpd_app *) app, req, res);
        rpd_res_headers_str(&headers_buff, res);
        mg_http_reply(conn, res->status, headers_buff, res->body ? res->body : "");

        free(headers_buff);
        rpd_req_cleanup(req);
        rpd_res_cleanup(res);
        free(req);
        free(res);
    }
}

int rpd_tcp_server_start(rpd_app *app, const char *addr)
{
    struct mg_mgr mgr;
    struct mg_connection *c;
    app->running = 1;

    /* setup signals handler */
    signal(SIGINT, signal_handler);
    signal(SIGTERM, signal_handler);
    mg_mgr_init(&mgr);

    if ((c = mg_http_listen(&mgr, addr, handle_request, app)) == NULL) {
        MG_ERROR(("Cannot listen on %s. Use http://ADDR:PORT or :PORT", addr));
        return EXIT_FAILURE;
    }
    MG_INFO(("Mongoose version : v%s", MG_VERSION));
    MG_INFO(("Rapida version   : v%s", RPD_VERSION));
    MG_INFO(("Listening on     : %s", addr));
    while (s_signo == 0 && app->running)
        mg_mgr_poll(&mgr, 1000);

    app->running = 0;
    MG_INFO(("Exiting on signal %d", s_signo));
    mg_mgr_free(&mgr);
    return 0;
}