/*
 dcc-chat.c : irssi

    Copyright (C) 1999-2000 Timo Sirainen

    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., 59 Temple Place, Suite 330, Boston, MA  02111-1307  USA
*/

#include "module.h"
#include "signals.h"
#include "commands.h"
#include "network.h"
#include "net-nonblock.h"
#include "line-split.h"
#include "settings.h"

#include "masks.h"
#include "irc.h"
#include "server-setup.h"

#include "dcc.h"

/* Send text to DCC chat */
static void dcc_chat_write(gchar *data)
{
    DCC_REC *dcc;
    gchar *params, *text, *target;
    gint len;

    g_return_if_fail(text != NULL);

    params = cmd_get_params(data, 2 | PARAM_FLAG_GETREST, &target, &text);

    if (*target == '=')
    {
        /* dcc msg */
        dcc = dcc_find_item(DCC_TYPE_CHAT, ++target, NULL);
        if (dcc != NULL)
	{
	    len = strlen(text);
	    /* FIXME: we need output queue! */
	    if (net_transmit(dcc->handle, text, len) != len)
		g_warning("dcc_chat_write() : could not send all data!");
	    net_transmit(dcc->handle, "\n", 1);
	}
    }

    g_free(params);
}

static void dcc_chat_me(const char *data, IRC_SERVER_REC *server, WI_IRC_REC *item)
{
	DCC_REC *dcc;
	char *str;

	g_return_if_fail(data != NULL);

	dcc = irc_item_dcc_chat(item);
	if (dcc == NULL) return;

	str = g_strdup_printf("ACTION %s", data);
	dcc_ctcp_message(dcc->nick, NULL, dcc, FALSE, str);
	g_free(str);
}

static void dcc_chat_action(const char *data, IRC_SERVER_REC *server)
{
	char *params, *target, *text;
	DCC_REC *dcc;
	char *str;

	g_return_if_fail(data != NULL);

	if (*data != '=') {
		/* handle only DCC actions */
		return;
	}

	params = cmd_get_params(data, 3 | PARAM_FLAG_GETREST, &target, &text);
	if (*target == '\0' || *text == '\0') cmd_param_error(CMDERR_NOT_ENOUGH_PARAMS);

	dcc = dcc_find_item(DCC_TYPE_CHAT, target+1, NULL);
	if (dcc != NULL) {
		str = g_strdup_printf("ACTION %s", data);
		dcc_ctcp_message(dcc->nick, NULL, dcc, FALSE, str);
		g_free(str);
	}
	g_free(params);
}

static void dcc_chat_ctcp(const char *data, IRC_SERVER_REC *server)
{
	char *params, *target, *ctcpcmd, *ctcpdata;
	DCC_REC *dcc;
	char *str;

	g_return_if_fail(data != NULL);
	if (server == NULL || !server->connected) cmd_return_error(CMDERR_NOT_CONNECTED);

	params = cmd_get_params(data, 3 | PARAM_FLAG_GETREST, &target, &ctcpcmd, &ctcpdata);
	if (*target == '\0' || *ctcpcmd == '\0') cmd_param_error(CMDERR_NOT_ENOUGH_PARAMS);

	if (*target != '=') {
		/* handle only DCC CTCPs */
		g_free(params);
		return;
	}

	dcc = dcc_find_item(DCC_TYPE_CHAT, target+1, NULL);
	if (dcc != NULL) {
		g_strup(ctcpcmd);

		str = g_strdup_printf("%s %s", ctcpcmd, ctcpdata);
		dcc_ctcp_message(dcc->nick, NULL, dcc, FALSE, str);
		g_free(str);
	}

	g_free(params);
}

/* DCC CHAT: text received */
static void dcc_chat_msg(DCC_REC *dcc, gchar *msg)
{
    gchar *cmd, *ptr;
    gboolean reply;

    g_return_if_fail(dcc != NULL);
    g_return_if_fail(msg != NULL);

    reply = FALSE;
    if (g_strncasecmp(msg, "CTCP_MESSAGE ", 13) != 0)
    {
        if (g_strncasecmp(msg, "CTCP_REPLY ", 11) != 0)
        {
            /* Use the mirc style CTCPing from now on.. */
	    dcc->mirc_ctcp = TRUE;
        }
        else
        {
            /* bitchx (and ircii?) sends this */
            msg += 11;
            reply = TRUE;
	    dcc->mirc_ctcp = FALSE;
        }
    }
    else
    {
        /* bitchx (and ircii?) sends this */
        msg += 13;
	dcc->mirc_ctcp = FALSE;
    }

    /* Handle only DCC CTCPs */
    if (*msg != 1)
        return;

    msg = g_strdup(msg+1);
    /* remove the later \001 */
    ptr = strrchr(msg, 1);
    if (ptr != NULL) *ptr = '\0';

    /* get ctcp command */
    cmd = g_strconcat(reply ? "dcc reply " : "dcc ctcp ", msg, NULL);
    ptr = strchr(cmd+9, ' ');
    if (ptr != NULL) *ptr++ = '\0'; else ptr = "";

    g_strdown(cmd+9);
    if (!signal_emit(cmd, 2, ptr, dcc))
        signal_emit(reply ? "default dcc reply" : "default dcc ctcp", 2, msg, dcc);

    g_free(cmd);
    g_free(msg);

    signal_stop();
}

/* input function: DCC CHAT received some data.. */
static void dcc_chat_input(DCC_REC *dcc)
{
        char tmpbuf[512], *str;
	int recvlen, ret;

	g_return_if_fail(dcc != NULL);

	do {
		recvlen = net_receive(dcc->handle, tmpbuf, sizeof(tmpbuf));

		ret = line_split(tmpbuf, recvlen, &str, (LINEBUF_REC **) &dcc->databuf);
		if (ret == -1) {
			/* connection lost */
			dcc->destroyed = TRUE;
			signal_emit("dcc closed", 1, dcc);
			dcc_destroy(dcc);
			break;
		}

		if (ret > 0) {
			dcc->transfd += ret;
			signal_emit("dcc chat message", 2, dcc, str);
		}
	} while (ret > 0);
}

/* input function: DCC CHAT - someone tried to connect to our socket */
static void dcc_chat_listen(DCC_REC *dcc)
{
    IPADDR ip;
    gint handle, port;

    g_return_if_fail(dcc != NULL);

    /* accept connection */
    handle = net_accept(dcc->handle, &ip, &port);
    if (handle == -1)
        return;

    /* FIXME: add paranoia checking, check if host ip is the same as to who
       we sent the DCC CHAT request.. */

    g_source_remove(dcc->tagread);
    close(dcc->handle);

    dcc->starttime = time(NULL);
    dcc->handle = handle;
    memcpy(&dcc->addr, &ip, sizeof(IPADDR));
    net_ip2host(&dcc->addr, dcc->addrstr);
    dcc->port = port;
    dcc->tagread = g_input_add(handle, G_INPUT_READ,
			       (GInputFunction) dcc_chat_input, dcc);

    signal_emit("dcc connected", 1, dcc);
}

/* callback: DCC CHAT - net_connect_nonblock() finished */
static void dcc_chat_connect(DCC_REC *dcc)
{
    g_return_if_fail(dcc != NULL);

    g_source_remove(dcc->tagread);
    if (net_geterror(dcc->handle) != 0)
    {
        /* error connecting */
        signal_emit("dcc error connect", 1, dcc);
        dcc_destroy(dcc);
        return;
    }

    /* connect ok. */
    dcc->starttime = time(NULL);
    dcc->tagread = g_input_add(dcc->handle, G_INPUT_READ,
			       (GInputFunction) dcc_chat_input, dcc);

    signal_emit("dcc connected", 1, dcc);
}

/* command: DCC CHAT */
static void cmd_dcc_chat(gchar *data, IRC_SERVER_REC *server)
{
    DCC_REC *dcc;
    IPADDR addr;
    gchar *str;
    gint port, handle;

    g_return_if_fail(data != NULL);
    if (*data == '\0') cmd_return_error(CMDERR_NOT_ENOUGH_PARAMS);

    dcc = dcc_find_item(DCC_TYPE_CHAT, data, NULL);
    if (dcc != NULL)
    {
	if (dcc->addrstr[0] == '\0' || dcc->starttime != 0)
	{
	    /* already sent a chat request / already chatting */
            return;
	}

	/* found from dcc list - so we're the connecting side.. */
	dcc->handle = net_connect_ip(&dcc->addr, dcc->port,
				     source_host_ok ? source_host_ip : NULL);
	if (dcc->handle != -1)
	{
	    dcc->tagread = g_input_add(dcc->handle, G_INPUT_WRITE,
				       (GInputFunction) dcc_chat_connect, dcc);
	}
	else
        {
            /* error connecting */
            signal_emit("dcc error connect", 1, dcc);
            dcc_destroy(dcc);
	}

        return;
    }

    /* send dcc chat request */
    if (server == NULL || !server->connected)
        cmd_return_error(CMDERR_NOT_CONNECTED);

    if (net_getsockname(server->handle, &addr, NULL) == -1)
        cmd_return_error(CMDERR_GETSOCKNAME);

    port = settings_get_int("dcc_port");
    handle = net_listen(&addr, &port);
    if (handle == -1)
        cmd_return_error(CMDERR_LISTEN);

    dcc = dcc_create(DCC_TYPE_CHAT, handle, data, "chat", server, NULL);
    dcc->tagread = g_input_add(dcc->handle, G_INPUT_READ,
			       (GInputFunction) dcc_chat_listen, dcc);

    /* send the request */
    str = g_strdup_printf("PRIVMSG %s :\001DCC CHAT CHAT %s %d\001",
			  data, dcc_make_address(&addr), port);
    irc_send_cmd(server, str);
    g_free(str);
}

static void cmd_mircdcc(gchar *data, IRC_SERVER_REC *server, WI_IRC_REC *item)
{
	DCC_REC *dcc;

	g_return_if_fail(data != NULL);

	dcc = irc_item_dcc_chat(item);
	if (dcc == NULL) return;

	dcc->mirc_ctcp = toupper(*data) == 'N' ? FALSE : TRUE;
}

static void dcc_ctcp_redirect(gchar *msg, DCC_REC *dcc)
{
    g_return_if_fail(msg != NULL);
    g_return_if_fail(dcc != NULL);

    signal_emit("ctcp msg dcc", 6, msg, dcc->server, dcc->nick, "dcc", dcc->mynick, dcc);
}

void dcc_chat_init(void)
{
    command_bind("msg", NULL, (SIGNAL_FUNC) dcc_chat_write);
    command_bind("me", NULL, (SIGNAL_FUNC) dcc_chat_me);
    command_bind("action", NULL, (SIGNAL_FUNC) dcc_chat_action);
    command_bind("ctcp", NULL, (SIGNAL_FUNC) dcc_chat_ctcp);
    command_bind("dcc chat", NULL, (SIGNAL_FUNC) cmd_dcc_chat);
    signal_add_first("dcc chat message", (SIGNAL_FUNC) dcc_chat_msg);
    command_bind("mircdcc", NULL, (SIGNAL_FUNC) cmd_mircdcc);
    signal_add("dcc ctcp dcc", (SIGNAL_FUNC) dcc_ctcp_redirect);
}

void dcc_chat_deinit(void)
{
    command_unbind("msg", (SIGNAL_FUNC) dcc_chat_write);
    command_unbind("me", (SIGNAL_FUNC) dcc_chat_me);
    command_unbind("action", (SIGNAL_FUNC) dcc_chat_action);
    command_unbind("ctcp", (SIGNAL_FUNC) dcc_chat_ctcp);
    command_unbind("dcc chat", (SIGNAL_FUNC) cmd_dcc_chat);
    signal_remove("dcc chat message", (SIGNAL_FUNC) dcc_chat_msg);
    command_unbind("mircdcc", (SIGNAL_FUNC) cmd_mircdcc);
    signal_remove("dcc ctcp dcc", (SIGNAL_FUNC) dcc_ctcp_redirect);
}