/*       +------------------------------------+
 *       | Inspire Internet Relay Chat Daemon |
 *       +------------------------------------+
 *
 *  Inspire is copyright (C) 2002-2005 ChatSpike-Dev.
 *                       E-mail:
 *                <brain@chatspike.net>
 *                <Craig@chatspike.net>
 *
 * Written by Craig Edwards, Craig McLure, and others.
 * This program is free but copyrighted software; see
 *            the file COPYING for details.
 *
 * ---------------------------------------------------
 */

using namespace std;

#include "inspircd_config.h"
#include "inspircd.h"
#include "inspircd_io.h"
#include <unistd.h>
#include <fcntl.h>
#include <sys/errno.h>
#include <sys/ioctl.h>
#include <sys/utsname.h>
#include <time.h>
#include <string>
#ifdef GCC3
#include <ext/hash_map>
#else
#include <hash_map>
#endif
#include <map>
#include <sstream>
#include <vector>
#include <deque>
#include <sched.h>
#ifdef THREADED_DNS
#include <pthread.h>
#endif
#include "users.h"
#include "ctables.h"
#include "globals.h"
#include "modules.h"
#include "dynamic.h"
#include "wildcard.h"
#include "message.h"
#include "mode.h"
#include "commands.h"
#include "xline.h"
#include "inspstring.h"
#include "dnsqueue.h"
#include "helperfuncs.h"
#include "hashcomp.h"
#include "socketengine.h"
#include "userprocess.h"
#include "socket.h"
#include "dns.h"
#include "typedefs.h"
#include "command_parse.h"

extern InspIRCd* ServerInstance;

extern std::vector<Module*> modules;
extern std::vector<ircd_module*> factory;
extern std::vector<InspSocket*> module_sockets;
extern std::vector<userrec*> local_users;

extern int MODCOUNT;
extern Module* IOHookModule;
extern InspSocket* socket_ref[65535];
extern time_t TIME;

extern SocketEngine* SE;

// This table references users by file descriptor.
// its an array to make it VERY fast, as all lookups are referenced
// by an integer, meaning there is no need for a scan/search operation.
extern userrec* fd_ref_table[65536];

extern serverstats* stats;
extern Server* MyServer;
extern ServerConfig *Config;

extern user_hash clientlist;
extern chan_hash chanlist;
extern command_table cmdlist;

/* This function pokes and hacks at a parameter list like the following:
 *
 * PART #winbot,#darkgalaxy :m00!
 *
 * to turn it into a series of individual calls like this:
 *
 * PART #winbot :m00!
 * PART #darkgalaxy :m00!
 *
 * The seperate calls are sent to a callback function provided by the caller
 * (the caller will usually call itself recursively). The callback function
 * must be a command handler. Calling this function on a line with no list causes
 * no action to be taken. You must provide a starting and ending parameter number
 * where the range of the list can be found, useful if you have a terminating
 * parameter as above which is actually not part of the list, or parameters
 * before the actual list as well. This code is used by many functions which
 * can function as "one to list" (see the RFC) */

int CommandParser::LoopCall(handlerfunc fn, char **parameters, int pcnt, userrec *u, int start, int end, int joins)
{
        char plist[MAXBUF];
        char *param;
        char *pars[32];
        char blog[32][MAXBUF];
        char blog2[32][MAXBUF];
        int j = 0, q = 0, total = 0, t = 0, t2 = 0, total2 = 0;
        char keystr[MAXBUF];
        char moo[MAXBUF];

        for (int i = 0; i <32; i++)
                strcpy(blog[i],"");

        for (int i = 0; i <32; i++)
                strcpy(blog2[i],"");

        strcpy(moo,"");
        for (int i = 0; i <10; i++)
        {
                if (!parameters[i])
                {
                        parameters[i] = moo;
                }
        }
        if (joins)
        {
                if (pcnt > 1) /* we have a key to copy */
                {
                        strlcpy(keystr,parameters[1],MAXBUF);
                }
        }

        if (!parameters[start])
        {
                return 0;
        }
        if (!strchr(parameters[start],','))
        {
                return 0;
        }
        strcpy(plist,"");
        for (int i = start; i <= end; i++)
        {
                if (parameters[i])
                {
                        strlcat(plist,parameters[i],MAXBUF);
                }
        }

        j = 0;
        param = plist;

        t = strlen(plist);
        for (int i = 0; i < t; i++)
        {
                if (plist[i] == ',')
                {
                        plist[i] = '\0';
                        strlcpy(blog[j++],param,MAXBUF);
                        param = plist+i+1;
                        if (j>20)
                        {
                                WriteServ(u->fd,"407 %s %s :Too many targets in list, message not delivered.",u->nick,blog[j-1]);
                                return 1;
                        }
                }
        }
        strlcpy(blog[j++],param,MAXBUF);
        total = j;

        if ((joins) && (keystr) && (total>0)) // more than one channel and is joining
        {
                strcat(keystr,",");
        }

        if ((joins) && (keystr))
        {
                if (strchr(keystr,','))
                {
                        j = 0;
                        param = keystr;
                        t2 = strlen(keystr);
                        for (int i = 0; i < t2; i++)
                        {
                                if (keystr[i] == ',')
                                {
                                        keystr[i] = '\0';
                                        strlcpy(blog2[j++],param,MAXBUF);
                                        param = keystr+i+1;
                                }
                        }
                        strlcpy(blog2[j++],param,MAXBUF);
                        total2 = j;
                }
        }

        for (j = 0; j < total; j++)
        {
                if (blog[j])
                {
                        pars[0] = blog[j];
                }
                for (q = end; q < pcnt-1; q++)
                {
                        if (parameters[q+1])
                        {
                                pars[q-end+1] = parameters[q+1];
                        }
                }
                if ((joins) && (parameters[1]))
                {
                        if (pcnt > 1)
                        {
                                pars[1] = blog2[j];
                        }
                        else
                        {
                                pars[1] = NULL;
                        }
                }
                /* repeatedly call the function with the hacked parameter list */
                if ((joins) && (pcnt > 1))
                {
                        if (pars[1])
                        {
                                // pars[1] already set up and containing key from blog2[j]
                                fn(pars,2,u);
                        }
                        else
                        {
                                pars[1] = parameters[1];
                                fn(pars,2,u);
                        }
                }
                else
                {
                        fn(pars,pcnt-(end-start),u);
                }
        }

        return 1;
}

bool CommandParser::IsValidCommand(std::string &commandname, int pcnt, userrec * user)
{
        for (unsigned int i = 0; i < cmdlist.size(); i++)
        {
                if (!strcasecmp(cmdlist[i].command,commandname.c_str()))
                {
                        if (cmdlist[i].handler_function)
                        {
                                if ((pcnt>=cmdlist[i].min_params) && (strcasecmp(cmdlist[i].source,"<core>")))
                                {
                                        if ((strchr(user->modes,cmdlist[i].flags_needed)) || (!cmdlist[i].flags_needed))
                                        {
                                                if (cmdlist[i].flags_needed)
                                                {
                                                        if ((user->HasPermission(commandname)) || (is_uline(user->server)))
                                                        {
                                                                return true;
                                                        }
                                                        else
                                                        {
                                                                return false;
                                                        }
                                                }
                                                return true;
                                        }
                                }
                        }
                }
        }
        return false;
}

// calls a handler function for a command

void CommandParser::CallHandler(std::string &commandname,char **parameters, int pcnt, userrec *user)
{
        for (unsigned int i = 0; i < cmdlist.size(); i++)
        {
                if (!strcasecmp(cmdlist[i].command,commandname.c_str()))
                {
                        if (cmdlist[i].handler_function)
                        {
                                if (pcnt>=cmdlist[i].min_params)
                                {
                                        if ((strchr(user->modes,cmdlist[i].flags_needed)) || (!cmdlist[i].flags_needed))
                                        {
                                                if (cmdlist[i].flags_needed)
                                                {
                                                        if ((user->HasPermission(commandname)) || (is_uline(user->server)))
                                                        {
                                                                cmdlist[i].handler_function(parameters,pcnt,user);
                                                        }
                                                }
                                                else
                                                {
                                                        cmdlist[i].handler_function(parameters,pcnt,user);
                                                }
                                        }
                                }
                        }
                }
        }
}

int CommandParser::ProcessParameters(char **command_p,char *parameters)
{
        int j = 0;
        int q = strlen(parameters);
        if (!q)
        {
                /* no parameters, command_p invalid! */
                return 0;
        }
        if (parameters[0] == ':')
        {
                command_p[0] = parameters+1;
                return 1;
        }
        if (q)
        {
                if ((strchr(parameters,' ')==NULL) || (parameters[0] == ':'))
                {
                        /* only one parameter */
                        command_p[0] = parameters;
                        if (parameters[0] == ':')
                        {
                                if (strchr(parameters,' ') != NULL)
                                {
                                        command_p[0]++;
                                }
                        }
                        return 1;
                }
        }
        command_p[j++] = parameters;
        for (int i = 0; i <= q; i++)
        {
                if (parameters[i] == ' ')
                {
                        command_p[j++] = parameters+i+1;
                        parameters[i] = '\0';
                        if (command_p[j-1][0] == ':')
                        {
                                *command_p[j-1]++; /* remove dodgy ":" */
                                break;
                                /* parameter like this marks end of the sequence */
                        }
                }
        }
        return j; /* returns total number of items in the list */
}

void CommandParser::ProcessCommand(userrec *user, char* cmd)
{
        char *parameters;
        char *command;
        char *command_p[127];
        char p[MAXBUF], temp[MAXBUF];
        int j, items, cmd_found;

        for (int i = 0; i < 127; i++)
                command_p[i] = NULL;

        if (!user)
        {
                return;
        }
        if (!cmd)
        {
                return;
        }
        if (!cmd[0])
        {
                return;
        }

        int total_params = 0;
        if (strlen(cmd)>2)
        {
                for (unsigned int q = 0; q < strlen(cmd)-1; q++)
                {
                        if ((cmd[q] == ' ') && (cmd[q+1] == ':'))
                        {
                                total_params++;
                                // found a 'trailing', we dont count them after this.
                                break;
                        }
                        if (cmd[q] == ' ')
                                total_params++;
                }
        }

        // another phidjit bug...
        if (total_params > 126)
        {
                *(strchr(cmd,' ')) = '\0';
                WriteServ(user->fd,"421 %s %s :Too many parameters given",user->nick,cmd);
                return;
        }

        strlcpy(temp,cmd,MAXBUF);

        std::string tmp = cmd;
        for (int i = 0; i <= MODCOUNT; i++)
        {
                std::string oldtmp = tmp;
                modules[i]->OnServerRaw(tmp,true,user);
                if (oldtmp != tmp)
                {
                        log(DEBUG,"A Module changed the input string!");
                        log(DEBUG,"New string: %s",tmp.c_str());
                        log(DEBUG,"Old string: %s",oldtmp.c_str());
                        break;
                }
        }
        strlcpy(cmd,tmp.c_str(),MAXBUF);
        strlcpy(temp,cmd,MAXBUF);

        if (!strchr(cmd,' '))
        {
                /* no parameters, lets skip the formalities and not chop up
                 * the string */
                log(DEBUG,"About to preprocess command with no params");
                items = 0;
                command_p[0] = NULL;
                parameters = NULL;
                for (unsigned int i = 0; i <= strlen(cmd); i++)
                {
                        cmd[i] = toupper(cmd[i]);
                }
                command = cmd;
        }
        else
        {
                strcpy(cmd,"");
                j = 0;
                /* strip out extraneous linefeeds through mirc's crappy pasting (thanks Craig) */
                for (unsigned int i = 0; i < strlen(temp); i++)
                {
                        if ((temp[i] != 10) && (temp[i] != 13) && (temp[i] != 0) && (temp[i] != 7))
                        {
                                cmd[j++] = temp[i];
                                cmd[j] = 0;
                        }
                }
                /* split the full string into a command plus parameters */
                parameters = p;
                strcpy(p," ");
                command = cmd;
                if (strchr(cmd,' '))
                {
                        for (unsigned int i = 0; i <= strlen(cmd); i++)
                        {
                                /* capitalise the command ONLY, leave params intact */
                                cmd[i] = toupper(cmd[i]);
                                /* are we nearly there yet?! :P */
                                if (cmd[i] == ' ')
                                {
                                        command = cmd;
                                        parameters = cmd+i+1;
                                        cmd[i] = '\0';
                                        break;
                                }
                        }
                }
                else
                {
                        for (unsigned int i = 0; i <= strlen(cmd); i++)
                        {
                                cmd[i] = toupper(cmd[i]);
                        }
                }

        }
        cmd_found = 0;

        if (strlen(command)>MAXCOMMAND)
        {
                WriteServ(user->fd,"421 %s %s :Command too long",user->nick,command);
                return;
        }

        for (unsigned int x = 0; x < strlen(command); x++)
        {
                if (((command[x] < 'A') || (command[x] > 'Z')) && (command[x] != '.'))
                {
                        if (((command[x] < '0') || (command[x]> '9')) && (command[x] != '-'))
                        {
                                if (strchr("@!\"$%^&*(){}[]_=+;:'#~,<>/?\\|`",command[x]))
                                {
                                        stats->statsUnknown++;
                                        WriteServ(user->fd,"421 %s %s :Unknown command",user->nick,command);
                                        return;
                                }
                        }
                }
        }

        std::string xcommand = command;
        for (unsigned int i = 0; i != cmdlist.size(); i++)
        {
                if (cmdlist[i].command[0])
                {
                        if (strlen(command)>=(strlen(cmdlist[i].command))) if (!strncmp(command, cmdlist[i].command,MAXCOMMAND))
                        {
                                if (parameters)
                                {
                                        if (parameters[0])
                                        {
                                                items = process_parameters(command_p,parameters);
                                        }
                                        else
                                        {
                                                items = 0;
                                                command_p[0] = NULL;
                                        }
                                }
                                else
                                {
                                        items = 0;
                                        command_p[0] = NULL;
                                }

                                if (user)
                                {
                                        /* activity resets the ping pending timer */
                                        user->nping = TIME + user->pingmax;
                                        if ((items) < cmdlist[i].min_params)
                                        {
                                                log(DEBUG,"not enough parameters: %s %s",user->nick,command);
                                                WriteServ(user->fd,"461 %s %s :Not enough parameters",user->nick,command);
                                                return;
                                        }
                                        if ((!strchr(user->modes,cmdlist[i].flags_needed)) && (cmdlist[i].flags_needed))
                                        {
                                                log(DEBUG,"permission denied: %s %s",user->nick,command);
                                                WriteServ(user->fd,"481 %s :Permission Denied- You do not have the required operator privilages",user->nick);
                                                cmd_found = 1;
                                                return;
                                        }
                                        if ((cmdlist[i].flags_needed) && (!user->HasPermission(xcommand)))
                                        {
                                                log(DEBUG,"permission denied: %s %s",user->nick,command);
                                                WriteServ(user->fd,"481 %s :Permission Denied- Oper type %s does not have access to command %s",user->nick,user->oper,command);
                                                cmd_found = 1;
                                                return;
                                        }
                                        /* if the command isnt USER, PASS, or NICK, and nick is empty,
                                         * deny command! */
                                        if ((strncmp(command,"USER",4)) && (strncmp(command,"NICK",4)) && (strncmp(command,"PASS",4)))
                                        {
                                                if ((!isnick(user->nick)) || (user->registered != 7))
                                                {
                                                        log(DEBUG,"not registered: %s %s",user->nick,command);
                                                        WriteServ(user->fd,"451 %s :You have not registered",command);
                                                        return;
                                                }
                                        }
                                        if ((user->registered == 7) && (!strchr(user->modes,'o')))
                                        {
                                                std::stringstream dcmds(Config->DisabledCommands);
                                                while (!dcmds.eof())
                                                {
                                                        std::string thiscmd;
                                                        dcmds >> thiscmd;
                                                        if (!strcasecmp(thiscmd.c_str(),command))
                                                        {
                                                                // command is disabled!
                                                                WriteServ(user->fd,"421 %s %s :This command has been disabled.",user->nick,command);
                                                                return;
                                                        }
                                                }
                                        }
                                        if ((user->registered == 7) || (!strncmp(command,"USER",4)) || (!strncmp(command,"NICK",4)) || (!strncmp(command,"PASS",4)))
                                        {
                                                if (cmdlist[i].handler_function)
                                                {

                                                        /* ikky /stats counters */
                                                        if (temp)
                                                        {
                                                                cmdlist[i].use_count++;
                                                                cmdlist[i].total_bytes+=strlen(temp);
                                                        }

                                                        int MOD_RESULT = 0;
                                                        FOREACH_RESULT(OnPreCommand(command,command_p,items,user));
                                                        if (MOD_RESULT == 1) {
                                                                return;
                                                        }

                                                        /* WARNING: nothing may come after the
                                                         * command handler call, as the handler
                                                         * may free the user structure! */

                                                        cmdlist[i].handler_function(command_p,items,user);
                                                }
                                                return;
                                        }
                                        else
                                        {
                                                WriteServ(user->fd,"451 %s :You have not registered",command);
                                                return;
                                        }
                                }
                                cmd_found = 1;
                        }

                }
        }
        if ((!cmd_found) && (user))
        {
                stats->statsUnknown++;
                WriteServ(user->fd,"421 %s %s :Unknown command",user->nick,command);
        }
}

bool CommandParser::RemoveCommands(const char* source)
{
        bool go_again = true;
        while (go_again)
        {
                go_again = false;
                for (std::deque<command_t>::iterator i = cmdlist.begin(); i != cmdlist.end(); i++)
                {
                        if (!strcmp(i->source,source))
                        {
                                log(DEBUG,"removecommands(%s) Removing dependent command: %s",i->source,i->command);
                                cmdlist.erase(i);
                                go_again = true;
                                break;
                        }
                }
        }
        return true;
}

void CommandParser::ProcessBuffer(const char* cmdbuf,userrec *user)
{
        if (!user)
        {
                log(DEFAULT,"*** BUG *** process_buffer was given an invalid parameter");
                return;
        }
        char cmd[MAXBUF];
        if (!cmdbuf)
        {
                log(DEFAULT,"*** BUG *** process_buffer was given an invalid parameter");
                return;
        }
        if (!cmdbuf[0])
        {
                return;
        }
        while (*cmdbuf == ' ') cmdbuf++; // strip leading spaces

        strlcpy(cmd,cmdbuf,MAXBUF);
        if (!cmd[0])
        {
                return;
        }
        int sl = strlen(cmd)-1;
        if ((cmd[sl] == 13) || (cmd[sl] == 10))
        {
                cmd[sl] = '\0';
        }
        sl = strlen(cmd)-1;
        if ((cmd[sl] == 13) || (cmd[sl] == 10))
        {
                cmd[sl] = '\0';
        }
        sl = strlen(cmd)-1;
        while (cmd[sl] == ' ') // strip trailing spaces
        {
                cmd[sl] = '\0';
                sl = strlen(cmd)-1;
        }

        if (!cmd[0])
        {
                return;
        }
        log(DEBUG,"CMDIN: %s %s",user->nick,cmd);
        tidystring(cmd);
        if ((user) && (cmd))
        {
                this->ProcessCommand(user,cmd);
        }
}

void CommandParser::CreateCommand(char* cmd, handlerfunc f, char flags, int minparams,char* source)
{
        command_t comm;
        /* create the command and push it onto the table */
        strlcpy(comm.command,cmd,MAXBUF);
        strlcpy(comm.source,source,MAXBUF);
        comm.handler_function = f;
        comm.flags_needed = flags;
        comm.min_params = minparams;
        comm.use_count = 0;
        comm.total_bytes = 0;
        cmdlist.push_back(comm);
        log(DEBUG,"Added command %s (%lu parameters)",cmd,(unsigned long)minparams);
}

CommandParser::CommandParser()
{
	this->SetupCommandTable();
}

void CommandParser::SetupCommandTable()
{
        this->CreateCommand("USER",handle_user,0,4,"<core>");
        this->CreateCommand("NICK",handle_nick,0,1,"<core>");
        this->CreateCommand("QUIT",handle_quit,0,0,"<core>");
        this->CreateCommand("VERSION",handle_version,0,0,"<core>");
        this->CreateCommand("PING",handle_ping,0,1,"<core>");
        this->CreateCommand("PONG",handle_pong,0,1,"<core>");
        this->CreateCommand("ADMIN",handle_admin,0,0,"<core>");
        this->CreateCommand("PRIVMSG",handle_privmsg,0,2,"<core>");
        this->CreateCommand("INFO",handle_info,0,0,"<core>");
        this->CreateCommand("TIME",handle_time,0,0,"<core>");
        this->CreateCommand("WHOIS",handle_whois,0,1,"<core>");
        this->CreateCommand("WALLOPS",handle_wallops,'o',1,"<core>");
        this->CreateCommand("NOTICE",handle_notice,0,2,"<core>");
        this->CreateCommand("JOIN",handle_join,0,1,"<core>");
        this->CreateCommand("NAMES",handle_names,0,0,"<core>");
        this->CreateCommand("PART",handle_part,0,1,"<core>");
        this->CreateCommand("KICK",handle_kick,0,2,"<core>");
        this->CreateCommand("MODE",handle_mode,0,1,"<core>");
        this->CreateCommand("TOPIC",handle_topic,0,1,"<core>");
        this->CreateCommand("WHO",handle_who,0,1,"<core>");
        this->CreateCommand("MOTD",handle_motd,0,0,"<core>");
        this->CreateCommand("RULES",handle_rules,0,0,"<core>");
        this->CreateCommand("OPER",handle_oper,0,2,"<core>");
        this->CreateCommand("LIST",handle_list,0,0,"<core>");
        this->CreateCommand("DIE",handle_die,'o',1,"<core>");
        this->CreateCommand("RESTART",handle_restart,'o',1,"<core>");
        this->CreateCommand("KILL",handle_kill,'o',2,"<core>");
        this->CreateCommand("REHASH",handle_rehash,'o',0,"<core>");
        this->CreateCommand("LUSERS",handle_lusers,0,0,"<core>");
        this->CreateCommand("STATS",handle_stats,0,1,"<core>");
        this->CreateCommand("USERHOST",handle_userhost,0,1,"<core>");
        this->CreateCommand("AWAY",handle_away,0,0,"<core>");
        this->CreateCommand("ISON",handle_ison,0,0,"<core>");
        this->CreateCommand("SUMMON",handle_summon,0,0,"<core>");
        this->CreateCommand("USERS",handle_users,0,0,"<core>");
        this->CreateCommand("INVITE",handle_invite,0,0,"<core>");
        this->CreateCommand("PASS",handle_pass,0,1,"<core>");
        this->CreateCommand("TRACE",handle_trace,'o',0,"<core>");
        this->CreateCommand("WHOWAS",handle_whowas,0,1,"<core>");
        this->CreateCommand("CONNECT",handle_connect,'o',1,"<core>");
        this->CreateCommand("SQUIT",handle_squit,'o',0,"<core>");
        this->CreateCommand("MODULES",handle_modules,0,0,"<core>");
        this->CreateCommand("LINKS",handle_links,0,0,"<core>");
        this->CreateCommand("MAP",handle_map,0,0,"<core>");
        this->CreateCommand("KLINE",handle_kline,'o',1,"<core>");
        this->CreateCommand("GLINE",handle_gline,'o',1,"<core>");
        this->CreateCommand("ZLINE",handle_zline,'o',1,"<core>");
        this->CreateCommand("QLINE",handle_qline,'o',1,"<core>");
        this->CreateCommand("ELINE",handle_eline,'o',1,"<core>");
        this->CreateCommand("LOADMODULE",handle_loadmodule,'o',1,"<core>");
        this->CreateCommand("UNLOADMODULE",handle_unloadmodule,'o',1,"<core>");
        this->CreateCommand("SERVER",handle_server,0,0,"<core>");
        this->CreateCommand("COMMANDS",handle_commands,0,0,"<core>");
}