/*
 * Copyright (C) Max Romanov
 * Copyright (C) NGINX, Inc.
 */

#include <nxt_main.h>
#include <nxt_application.h>


static nxt_int_t nxt_go_init(nxt_task_t *task);

static nxt_int_t nxt_go_prepare_msg(nxt_task_t *task,
                      nxt_app_request_t *r, nxt_app_wmsg_t *msg);

static nxt_int_t nxt_go_run(nxt_task_t *task,
                      nxt_app_rmsg_t *rmsg, nxt_app_wmsg_t *msg);

static nxt_str_t nxt_go_path;

nxt_application_module_t  nxt_go_module = {
    nxt_go_init,
    nxt_go_prepare_msg,
    nxt_go_run
};


nxt_int_t
nxt_go_module_init(nxt_thread_t *thr, nxt_runtime_t *rt);

nxt_int_t
nxt_go_module_init(nxt_thread_t *thr, nxt_runtime_t *rt)
{
    char        **argv;
    u_char      *p;

    argv = nxt_process_argv;

    while (*argv != NULL) {
        p = (u_char *) *argv++;

        if (nxt_strcmp(p, "--go") == 0) {
            if (*argv == NULL) {
                nxt_log_error(NXT_LOG_ERR, thr->log,
                              "no argument for option \"--go\"");
                return NXT_ERROR;
            }

            p = (u_char *) *argv;

            nxt_go_path.start = p;
            nxt_go_path.length = nxt_strlen(p);

            nxt_log_error(NXT_LOG_INFO, thr->log,
                          "go program \"%V\"",
                          &nxt_go_path);

            nxt_app = &nxt_go_module;

            return NXT_OK;
        }
    }

    nxt_log_error(NXT_LOG_ERR, thr->log, "no option \"--go\" specified");

    return NXT_ERROR;
}

extern char  **environ;

nxt_inline int
nxt_sock_no_cloexec(nxt_socket_t fd)
{
    if (fd == -1) {
        return 0;
    }
    return fcntl(fd, F_SETFD, 0);
}

static nxt_int_t
nxt_go_init(nxt_task_t *task)
{
    char *go_ports = getenv("NXT_GO_PORTS");

    nxt_debug(task, "initialize go app, NXT_GO_PORTS=%s",
              go_ports ? go_ports : "NULL");

    if (go_ports == NULL) {
        u_char buf[256];
        u_char *p = buf;

        nxt_runtime_t *rt = task->thread->runtime;
        nxt_port_t *port;

        nxt_runtime_port_each(rt, port) {

            nxt_debug(task, "port %PI, %ud, (%d, %d)", port->pid, port->id,
                      port->pair[0], port->pair[1]);

            p = nxt_sprintf(p, buf + sizeof(buf), "%PI,%ud,%d,%d,%d;",
                            port->pid, port->id, (int)port->type,
                            port->pair[0], port->pair[1]);

            if (nxt_slow_path(nxt_sock_no_cloexec(port->pair[0]))) {
                nxt_log(task, NXT_LOG_WARN, "fcntl() failed %E", nxt_errno);
            }

            if (nxt_slow_path(nxt_sock_no_cloexec(port->pair[1]))) {
                nxt_log(task, NXT_LOG_WARN, "fcntl() failed %E", nxt_errno);
            }

        } nxt_runtime_port_loop;

        *p = '\0';
        nxt_debug(task, "update NXT_GO_PORTS=%s", buf);

        setenv("NXT_GO_PORTS", (char *)buf, 1);

        char *argv[] = {
            (char *)nxt_go_path.start,
            (char *)"--no-daemonize",
            (char *)"--app", NULL };

        (void) execve((char *)nxt_go_path.start, argv, environ);

        nxt_log(task, NXT_LOG_WARN, "execve(%V) failed %E", &nxt_go_path,
                nxt_errno);

        return NXT_ERROR;
    }

    return NXT_OK;
}


static nxt_int_t
nxt_go_prepare_msg(nxt_task_t *task, nxt_app_request_t *r, nxt_app_wmsg_t *wmsg)
{
    nxt_int_t                 rc;
    nxt_http_field_t          *field;
    nxt_app_request_header_t  *h;

    static const nxt_str_t eof = nxt_null_string;

    h = &r->header;

#define RC(S)                                                                 \
    do {                                                                      \
        rc = (S);                                                             \
        if (nxt_slow_path(rc != NXT_OK)) {                                    \
            goto fail;                                                        \
        }                                                                     \
    } while(0)

#define NXT_WRITE(N)                                                          \
    RC(nxt_app_msg_write_str(task, wmsg, N))

    /* TODO error handle, async mmap buffer assignment */

    NXT_WRITE(&h->method);
    NXT_WRITE(&h->path);

    if (h->query.start != NULL) {
        RC(nxt_app_msg_write_size(task, wmsg,
                                  h->query.start - h->path.start + 1));
    } else {
        RC(nxt_app_msg_write_size(task, wmsg, 0));
    }

    NXT_WRITE(&h->version);

    NXT_WRITE(&h->host);
    NXT_WRITE(&h->cookie);
    NXT_WRITE(&h->content_type);
    NXT_WRITE(&h->content_length);

    RC(nxt_app_msg_write_size(task, wmsg, h->parsed_content_length));

    nxt_list_each(field, h->fields) {
        NXT_WRITE(&field->name);
        NXT_WRITE(&field->value);

    } nxt_list_loop;

    /* end-of-headers mark */
    NXT_WRITE(&eof);
    NXT_WRITE(&r->body.preread);

#undef NXT_WRITE
#undef RC

    return NXT_OK;

fail:

    return NXT_ERROR;
}


static nxt_int_t
nxt_go_run(nxt_task_t *task,
           nxt_app_rmsg_t *rmsg, nxt_app_wmsg_t *msg)
{
    return NXT_ERROR;
}