/* myMPD
   (c) 2018-2019 Juergen Mang <mail@jcgames.de>
   This project's homepage is: https://github.com/jcorporation/mympd
   
   myMPD ist fork of: ympd (c) 2013-2014 Andrew Karpow <andy@ndyk.de>
   ympd project's homepage is: http://www.ympd.org
   
   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; version 2 of the License.

   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.,
   Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
*/

#define _GNU_SOURCE

#include <stdlib.h>
#include <string.h>
#include <stdio.h>
#include <unistd.h>
#include <sys/time.h>
#include <pwd.h>
#include <grp.h>
#include <libgen.h>
#include <pthread.h>
#include <dirent.h>
#include <mpd/client.h>
#include <stdbool.h>

#include "list.h"
#include "tiny_queue.h"
#include "global.h"
#include "mpd_client.h"
#include "../dist/src/mongoose/mongoose.h"
#include "web_server.h"
#include "mympd_api.h"
#include "../dist/src/inih/ini.h"


static void mympd_signal_handler(int sig_num) {
    signal(sig_num, mympd_signal_handler);  // Reinstantiate signal handler
    s_signal_received = sig_num;
    //Wakeup mympd_api_loop
    pthread_cond_signal(&mympd_api_queue->wakeup);
}

static int mympd_inihandler(void *user, const char *section, const char *name, const char* value) {
    t_config* p_config = (t_config*)user;
    char *crap;

    #define MATCH(s, n) strcasecmp(section, s) == 0 && strcasecmp(name, n) == 0

    if (MATCH("mpd", "host")) {
        free(p_config->mpdhost);
        p_config->mpdhost = strdup(value);
    }
    else if (MATCH("mpd", "port")) {
        p_config->mpdport = strtol(value, &crap, 10);
    }
    else if (MATCH("mpd", "pass")) {
        free(p_config->mpdpass);
        p_config->mpdpass = strdup(value);
    }
    else if (MATCH("mpd", "streamport")) {
        p_config->streamport = strtol(value, &crap, 10);
    }
    else if (MATCH("webserver", "webport")) {
        free(p_config->webport);
        p_config->webport = strdup(value);
    }
    else if (MATCH("webserver", "ssl")) {
        p_config->ssl = strcmp(value, "true") == 0 ? true : false;
    }
    else if (MATCH("webserver", "sslport")) {
        free(p_config->sslport);
        p_config->sslport = strdup(value);
    }
    else if (MATCH("webserver", "sslcert")) {
        free(p_config->sslcert);
        p_config->sslcert = strdup(value);
    }
    else if (MATCH("webserver", "sslkey")) {
        free(p_config->sslkey);
        p_config->sslkey = strdup(value);
    }
    else if (MATCH("mympd", "user")) {
        free(p_config->user);
        p_config->user = strdup(value);
    }
    else if (MATCH("mympd", "coverimage")) {
        p_config->coverimage = strcmp(value, "true") == 0 ? true : false;
    }
    else if (MATCH("mympd", "coverimagename")) {
        free(p_config->coverimagename);
        p_config->coverimagename = strdup(value);
    }
    else if (MATCH("mympd", "coverimagesize")) {
        p_config->coverimagesize = strtol(value, &crap, 10);
    }
    else if (MATCH("mympd", "varlibdir")) {
        free(p_config->varlibdir);
        p_config->varlibdir = strdup(value);
    }
    else if (MATCH("mympd", "stickers")) {
        p_config->stickers = strcmp(value, "true") == 0 ? true : false;
    }
    else if (MATCH("mympd", "smartpls")) {
        p_config->smartpls =  strcmp(value, "true") == 0 ? true : false;
    }
    else if (MATCH("mympd", "mixramp")) {
        p_config->mixramp = strcmp(value, "true") == 0 ? true : false;
    }
    else if (MATCH("mympd", "taglist")) {
        free(p_config->taglist);
        p_config->taglist = strdup(value);
    }
    else if (MATCH("mympd", "searchtaglist")) {
        free(p_config->searchtaglist);
        p_config->searchtaglist = strdup(value);
    }
    else if (MATCH("mympd", "browsetaglist")) {
        free(p_config->browsetaglist);
        p_config->browsetaglist = strdup(value);
    }
    else if (MATCH("mympd", "pagination")) {
        p_config->max_elements_per_page = strtol(value, &crap, 10);
        if (p_config->max_elements_per_page > MAX_ELEMENTS_PER_PAGE) {
            printf("Setting max_elements_per_page to maximal value %d", MAX_ELEMENTS_PER_PAGE);
            p_config->max_elements_per_page = MAX_ELEMENTS_PER_PAGE;
        }
    }
    else if (MATCH("mympd", "syscmds")) {
        p_config->syscmds = strcmp(value, "true") == 0 ? true : false;
    }
    else if (MATCH("mympd", "localplayer")) {
        p_config->localplayer = strcmp(value, "true") == 0 ? true : false;
    }
    else if (MATCH("mympd", "streamurl")) {
        free(p_config->streamurl);
        p_config->streamurl = strdup(value);
    }
    else if (MATCH("mympd", "lastplayedcount")) {
        p_config->last_played_count = strtol(value, &crap, 10);
    }
    else if (MATCH("mympd", "loglevel")) {
        p_config->loglevel = strtol(value, &crap, 10);
    }
    else if (MATCH("theme", "backgroundcolor")) {
        free(p_config->backgroundcolor);
        p_config->backgroundcolor = strdup(value);
    }
    else {
        printf("WARN: Unkown config option: %s - %s\n", section, name);
        return 0;  
    }

    return 1;
}

static void mympd_free_config(t_config *config) {
    free(config->mpdhost);
    free(config->mpdpass);
    free(config->webport);
    free(config->sslport);
    free(config->sslcert);
    free(config->sslkey);
    free(config->user);
    free(config->coverimagename);
    free(config->taglist);
    free(config->searchtaglist);
    free(config->browsetaglist);
    free(config->varlibdir);
    free(config->etcdir);
    free(config->streamurl);
    free(config->backgroundcolor);
    free(config);
}

static void mympd_parse_env(struct t_config *config, const char *envvar) {
    char *name, *section;
    const char *value = getenv(envvar);
    if (value != NULL) {
        char *var = strdup(envvar);
        section = strtok_r(var, "_", &name);
        if (section != NULL && name != NULL) {
            LOG_DEBUG() printf("DEBUG: Using environment variable %s_%s: %s\n", section, name, value);
            mympd_inihandler(config, section, name, value);
        }
        value = NULL;
        free(var);
    }
}

static void mympd_get_env(struct t_config *config) {
    const char* env_vars[]={"MPD_HOST", "MPD_PORT", "MPD_PASS", "MPD_STREAMPORT",
        "WEBSERVER_WEBPORT", "WEBSERVER_SSL", "WEBSERVER_SSLPORT", "WEBSERVER_SSLCERT", "WEBSERVER_SSLKEY",
        "MYMPD_LOGLEVEL", "MYMPD_USER", "MYMPD_LOCALPLAYER", "MYMPD_COVERIMAGE", "MYMPD_COVERIMAGENAME", 
        "MYMPD_COVERIMAGESIZE", "MYMPD_VARLIBDIR", "MYMPD_MIXRAMP", "MYMPD_STICKERS", "MYMPD_TAGLIST", 
        "MYMPD_SEARCHTAGLIST", "MYMPD_BROWSETAGLIST", "MYMPD_SMARTPLS", "MYMPD_SYSCMDS", 
        "MYMPD_PAGINATION", "MYMPD_LASTPLAYEDCOUNT",
        "THEME_BACKGROUNDCOLOR", 0};
    const char** ptr = env_vars;
    while (*ptr != 0) {
        mympd_parse_env(config, *ptr);
        ++ptr;
    }
}

int main(int argc, char **argv) {
    s_signal_received = 0;
    char testdirname[400];
    bool init_webserver = false;
    bool init_thread_webserver = false;
    bool init_thread_mpdclient = false;
    bool init_thread_mympdapi = false;
    int rc = EXIT_FAILURE;
    
    mpd_client_queue = tiny_queue_create();
    mympd_api_queue = tiny_queue_create();
    web_server_queue = tiny_queue_create();

    t_user_data *user_data = (t_user_data*)malloc(sizeof(t_user_data));

    srand((unsigned int)time(NULL));
    
    //mympd config defaults
    t_config *config = (t_config *)malloc(sizeof(t_config));
    config->mpdhost = strdup("127.0.0.1");
    config->mpdport = 6600;
    config->mpdpass = NULL;
    config->webport = strdup("80");
    config->ssl = true;
    config->sslport = strdup("443");
    config->sslcert = strdup("/etc/mympd/ssl/server.pem");
    config->sslkey = strdup("/etc/mympd/ssl/server.key");
    config->user = strdup("mympd");
    config->streamport = 8000;
    config->streamurl = strdup("");
    config->coverimage = true;
    config->coverimagename = strdup("folder.jpg");
    config->coverimagesize = 240;
    config->varlibdir = strdup("/var/lib/mympd");
    config->stickers = true;
    config->mixramp = true;
    config->taglist = strdup("Artist,Album,AlbumArtist,Title,Track,Genre,Date,Composer,Performer");
    config->searchtaglist = strdup("Artist,Album,AlbumArtist,Title,Genre,Composer,Performer");
    config->browsetaglist = strdup("Artist,Album,AlbumArtist,Genre,Composer,Performer");
    config->smartpls = true;
    config->max_elements_per_page = 100;
    config->last_played_count = 20;
    config->etcdir = strdup("/etc/mympd");
    config->syscmds = false;
    config->localplayer = true;
    config->loglevel = 1;
    config->backgroundcolor = strdup("#888");

    char *configfile = strdup("/etc/mympd/mympd.conf");
    if (argc == 2) {
        if (strncmp(argv[1], "/", 1) == 0) {
            printf("Starting myMPD %s\n", MYMPD_VERSION);
            printf("Libmpdclient %i.%i.%i\n", LIBMPDCLIENT_MAJOR_VERSION, LIBMPDCLIENT_MINOR_VERSION, LIBMPDCLIENT_PATCH_VERSION);
            free(configfile);
            configfile = argv[1];
            char *etcdir = strdup(configfile);
            free(config->etcdir);
            config->etcdir = strdup(dirname(etcdir));
            free(etcdir);
        }
        else {
            printf("myMPD  %s\n"
                "Copyright (C) 2018-2019 Juergen Mang <mail@jcgames.de>\n"
                "https://github.com/jcorporation/myMPD\n"
                "Built " __DATE__ " "__TIME__"\n\n"
                "Usage: %s [/path/to/mympd.conf]\n",
                MYMPD_VERSION,
                argv[0]
            );
            goto cleanup;
        }
    }
    if (access(configfile, F_OK ) != -1) {
        printf("Parsing config file: %s\n", configfile);
        if (ini_parse(configfile, mympd_inihandler, config) < 0) {
            printf("Can't load config file \"%s\"\n", configfile);
            goto cleanup;
        }
    }
    else {
        printf("No config file found, using defaults\n");
    }

    //read environment - overwrites config file definitions
    mympd_get_env(config);
    
    #ifdef DEBUG
    printf("Debug flag enabled, setting loglevel to debug\n");
    config->loglevel = 3;
    #endif
    printf("Setting loglevel to %ld\n", config->loglevel);
    loglevel = config->loglevel;

    //set signal handler
    signal(SIGTERM, mympd_signal_handler);
    signal(SIGINT, mympd_signal_handler);
    setvbuf(stdout, NULL, _IOLBF, 0);
    setvbuf(stderr, NULL, _IOLBF, 0);

    //init webserver
    struct mg_mgr mgr;
    if (!web_server_init(&mgr, config, user_data)) {
        goto cleanup;
    }
    else {
        init_webserver = true;
    }

    //drop privileges
    if (getuid() == 0) {
        if (config->user != NULL || strlen(config->user) != 0) {
            printf("Droping privileges to %s\n", config->user);
            struct passwd *pw;
            if ((pw = getpwnam(config->user)) == NULL) {
                printf("ERROR: getpwnam() failed, unknown user\n");
                goto cleanup;
            } else if (setgroups(0, NULL) != 0) { 
                printf("ERROR: setgroups() failed\n");
                goto cleanup;
            } else if (setgid(pw->pw_gid) != 0) {
                printf("ERROR: setgid() failed\n");
                goto cleanup;
            } else if (setuid(pw->pw_uid) != 0) {
                printf("ERROR: setuid() failed\n");
                goto cleanup;
            }
        }
    }
    
    if (getuid() == 0) {
        printf("myMPD should not be run with root privileges\n");
        goto cleanup;
    }

    //check needed directories
    if (!testdir("Document root", DOC_ROOT)) {
        goto cleanup;
    }

    snprintf(testdirname, 400, "%s/library", DOC_ROOT);
    if (!testdir("Link to mpd music_directory", testdirname)) {
        printf("Disabling coverimage support\n");
        config->coverimage = false;
    }

    snprintf(testdirname, 400, "%s/tmp", config->varlibdir);
    if (!testdir("Temp dir", testdirname)) {
        goto cleanup;
    }

    snprintf(testdirname, 400, "%s/smartpls", config->varlibdir);
    if (!testdir("Smartpls dir", testdirname)) {
        goto cleanup;
    }

    snprintf(testdirname, 400, "%s/state", config->varlibdir);
    if (!testdir("State dir", testdirname)) {
        goto cleanup;
    }

    if (config->syscmds == true) {
        snprintf(testdirname, 400, "%s/syscmds", config->etcdir);
        if (!testdir("Syscmds directory", testdirname)) {
            printf("Disabling syscmd support\n");
            config->syscmds = false;
        }
    }

    //Create working threads
    pthread_t mpd_client_thread, web_server_thread, mympd_api_thread;
    //mpd connection
    if (pthread_create(&mpd_client_thread, NULL, mpd_client_loop, config) == 0) {
        pthread_setname_np(mpd_client_thread, "mympd_mpdclient");
        init_thread_mpdclient = true;
    }
    else {
        printf("ERROR: can't create mympd_client thread\n");
        s_signal_received = SIGTERM;
    }
    //webserver
    if (pthread_create(&web_server_thread, NULL, web_server_loop, &mgr) == 0) {
        pthread_setname_np(web_server_thread, "mympd_webserver");
        init_thread_webserver = true;
    }
    else {
        printf("ERROR: can't create mympd_webserver thread\n");
        s_signal_received = SIGTERM;
    }
    //mympd api
    if (pthread_create(&mympd_api_thread, NULL, mympd_api_loop, config) == 0) {
        pthread_setname_np(mympd_api_thread, "mympd_mympdapi");
        init_thread_mympdapi = true;
    }
    else {
        printf("ERROR: can't create mympd_mympdapi thread\n");
        s_signal_received = SIGTERM;
    }

    //Outsourced all work to separate threads, do nothing...
    rc = EXIT_SUCCESS;

    //Try to cleanup all
    cleanup:
    if (init_thread_mpdclient)
        pthread_join(mpd_client_thread, NULL);
    if (init_thread_webserver)
        pthread_join(web_server_thread, NULL);
    if (init_thread_mympdapi)
        pthread_join(mympd_api_thread, NULL);
    if (init_webserver)
        web_server_free(&mgr);
    tiny_queue_free(web_server_queue);
    tiny_queue_free(mpd_client_queue);
    tiny_queue_free(mympd_api_queue);
    mympd_free_config(config);
    free(configfile);
    free(user_data);
    return rc;
}