housewiz.c

/* HouseWiz - A simple home web server for control of Philips Wiz devices.
 *
 * Copyright 2020, Pascal Martin
 *
 * This program is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin Street, Fifth Floor,
 * Boston, MA  02110-1301, USA.
 *
 *
 * housewiz.c - Main loop of the housewiz program.
 *
 * SYNOPSYS:
 *
 */

#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <signal.h>

#include <time.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>

#include "echttp.h"
#include "echttp_cors.h"
#include "echttp_json.h"
#include "echttp_static.h"
#include "houseportalclient.h"
#include "houselog.h"
#include "houseconfig.h"

#include "housewiz_device.h"

static int use_houseportal = 0;

static const char *housewiz_status (const char *method, const char *uri,
                                    const char *data, int length) {
    static char buffer[65537];
    ParserToken token[1024];
    char pool[65537];
    int count = housewiz_device_count();
    int i;

    ParserContext context = echttp_json_start (token, 1024, pool, 65537);

    int root = echttp_json_add_object (context, 0, 0);
    echttp_json_add_string (context, root, "host", houselog_host());
    echttp_json_add_string (context, root, "proxy", houseportal_server());
    echttp_json_add_integer (context, root, "timestamp", (long)time(0));
    int top = echttp_json_add_object (context, root, "control");
    int container = echttp_json_add_object (context, top, "status");

    for (i = 0; i < count; ++i) {
        time_t pulsed = housewiz_device_deadline(i);
        const char *name = housewiz_device_name(i);
        const char *status = housewiz_device_failure(i);
        if (!status) status = housewiz_device_get(i)?"on":"off";
        const char *commanded = housewiz_device_commanded(i)?"on":"off";

        int point = echttp_json_add_object (context, container, name);
        echttp_json_add_string (context, point, "state", status);
        echttp_json_add_string (context, point, "command", commanded);
        if (pulsed)
            echttp_json_add_integer (context, point, "pulse", (int)pulsed);
        echttp_json_add_string (context, point, "gear", "light");
    }
    const char *error = echttp_json_export (context, buffer, 65537);
    if (error) {
        echttp_error (500, error);
        return "";
    }
    echttp_content_type_json ();
    return buffer;
}

static const char *housewiz_set (const char *method, const char *uri,
                                 const char *data, int length) {

    const char *point = echttp_parameter_get("point");
    const char *statep = echttp_parameter_get("state");
    const char *pulsep = echttp_parameter_get("pulse");
    int state;
    int pulse;
    int i;
    int count = housewiz_device_count();
    int found = 0;

    if (!point) {
        echttp_error (404, "missing point name");
        return "";
    }
    if (!statep) {
        echttp_error (400, "missing state value");
        return "";
    }
    if ((strcmp(statep, "on") == 0) || (strcmp(statep, "1") == 0)) {
        state = 1;
    } else if ((strcmp(statep, "off") == 0) || (strcmp(statep, "0") == 0)) {
        state = 0;
    } else {
        echttp_error (400, "invalid state value");
        return "";
    }

    pulse = pulsep ? atoi(pulsep) : 0;
    if (pulse < 0) {
        echttp_error (400, "invalid pulse value");
        return "";
    }

    for (i = 0; i < count; ++i) {
       if ((strcmp (point, "all") == 0) ||
           (strcmp (point, housewiz_device_name(i)) == 0)) {
           found = 1;
           housewiz_device_set (i, state, pulse);
       }
    }

    if (! found) {
        echttp_error (404, "invalid point name");
        return "";
    }
    return housewiz_status (method, uri, data, length);
}

static const char *housewiz_config (const char *method, const char *uri,
                                  const char *data, int length) {

    if (strcmp ("GET", method) == 0) {
        static char buffer[65537];
        housewiz_device_live_config (buffer, sizeof(buffer));
        echttp_content_type_json ();
        return buffer;
    } else if (strcmp ("POST", method) == 0) {
        const char *error = houseconfig_update(data);
        if (error) echttp_error (400, error);
        housewiz_device_refresh("AFTER UPDATE");
    } else {
        echttp_error (400, "invalid method");
    }
    return "";
}

static void housewiz_background (int fd, int mode) {

    time_t now = time(0);

    if (use_houseportal) {
        static time_t LastRenewal = 0;
        if (now >= LastRenewal + 60) {
            if (LastRenewal > 0) {
                houseportal_renew();
            } else {
                static const char *path[] = {"control:/wiz"};
                houseportal_register (echttp_port(4), path, 1);
            }
            LastRenewal = now;
        }
    }
    housewiz_device_periodic(now);
    if (housewiz_device_changed()) {
        static char buffer[65537];
        housewiz_device_live_config (buffer, sizeof(buffer));
        houseconfig_update(buffer);
        if (echttp_isdebug()) fprintf (stderr, "Configuration saved\n");
    }
}

static void housewiz_protect (const char *method, const char *uri) {
    echttp_cors_protect(method, uri);
}

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

    const char *error;

    // These strange statements are to make sure that fds 0 to 2 are
    // reserved, since this application might output some errors.
    // 3 descriptors are wasted if 0, 1 and 2 are already open. No big deal.
    //
    open ("/dev/null", O_RDONLY);
    dup(open ("/dev/null", O_WRONLY));

    signal(SIGPIPE, SIG_IGN);

    echttp_default ("-http-service=dynamic");

    argc = echttp_open (argc, argv);
    if (echttp_dynamic_port()) {
        houseportal_initialize (argc, argv);
        use_houseportal = 1;
    }
    houselog_initialize ("wiz", argc, argv);

    houseconfig_default ("--config=wiz");
    error = houseconfig_load (argc, argv);
    if (error) {
        houselog_trace
            (HOUSE_FAILURE, "CONFIG", "Cannot load configuration: %s\n", error);
    }
    error = housewiz_device_initialize (argc, argv);
    if (error) {
        houselog_trace
            (HOUSE_FAILURE, "PLUG", "Cannot initialize: %s\n", error);
        exit(1);
    }

    echttp_cors_allow_method("GET");
    echttp_protect (0, housewiz_protect);

    echttp_route_uri ("/wiz/status", housewiz_status);
    echttp_route_uri ("/wiz/set",    housewiz_set);

    echttp_route_uri ("/wiz/config", housewiz_config);

    echttp_static_route ("/", "/usr/local/share/house/public");
    echttp_background (&housewiz_background);
    houselog_event ("SERVICE", "wiz", "STARTED", "ON %s", houselog_host());
    echttp_loop();
}