module BTS_Tests_ASCI {

/* ASCI Integration Tests for OsmoBTS
 *
 * (C) 2023 by sysmocom - s.f.m.c. GmbH <info@sysmocom.de>
 * All Rights Reserved
 *
 * SPDX-License-Identifier: AGPL-3.0+
 *
 * Authors: Harald Welte; Andreas Eversberg
 *
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU Affero General Public License as published by
 * the Free Software Foundation; either version 3 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 Affero General Public License for more details.
 *
 * You should have received a copy of the GNU Affero General Public License
 * along with this program.  If not, see <http://www.gnu.org/licenses/>.
 */

import from Misc_Helpers all;
import from General_Types all;
import from Osmocom_Types all;
import from GSM_Types all;
import from L1CTL_PortType all;
import from L1CTL_Types all;
import from LAPDm_Types all;
import from IPA_Emulation all;
import from GSM_RR_Types all;
import from L3_Templates all;

import from MobileL3_CommonIE_Types all;

import from RSL_Emulation all;
import from RSL_Types all;

import from BTS_Tests all;


/* convert from boolean value to BIT1 */
private function bool2bit1(boolean inp) return BIT1 {
	if (inp) {
		return '1'B;
	} else {
		return '0'B;
	}
}

/* encode a VBS/VGCS call reference into it's OCT5 representation */
private function f_enc_gcr(integer call_ref, boolean is_group_call, boolean ack_required := false)
return OCT5
{
	var DescriptiveGroupOrBroadcastCallReference_V v := {
		binaryCodingOfGroupOrBroadcastCallReference := int2bit(call_ref, 27),
		sF := bool2bit1(is_group_call),
		aF := bool2bit1(ack_required),
		callPriority := '000'B,
		cipheringInformation := '0000'B,
		spare := '0000'B
	}
	return bit2oct(encvalue(v));
}

/* Send Notification command to start and stop notifying an ASCI call.
 * When it starts, it is expected that NCH is received by MS. Also it is expected that NCH is received again.
 * When it stops, it is expected that NCH is not received anymore. */
testcase TC_vbs_notification() runs on test_CT
{
	timer T;

	f_init();
	f_init_l1ctl();
	f_l1_tune(L1CTL);

	var OCT5 gcr := f_enc_gcr(hex2int('2342'H), false, false);
	var OCT3 chan_desc := '234266'O;
	var octetstring notif_nch := '090620B42230000091A1330B2B2B2B2B2B2B2B2B2B2B2B'O;
	var integer recv_count := 0;

	log("Sending RSL NOTIF_CMD (start)");
	RSL_CCHAN.send(ts_ASP_RSL_UD(ts_RSL_NOTIF_CMD_START(gcr, chan_desc)));

	/* NCH must be received twice. */
	T.start(2.0);
	alt {
	[] L1CTL.receive(tr_L1CTL_DATA_IND(t_RslChanNr_PCH_AGCH(0), ?, notif_nch)) {
		log("Received matching NOTIFICATION/NCH.");
		recv_count := recv_count + 1;
		if (recv_count != 2) {
			repeat;
		}
		T.stop;
		}
	[] L1CTL.receive { repeat; }
	[] T.timeout {
		setverdict(fail, "Timeout waiting for NCH message");
		}
	}

	log("Sending RSL NOTIF_CMD (stop)");
	RSL_CCHAN.send(ts_ASP_RSL_UD(ts_RSL_NOTIF_CMD_STOP(gcr)));

	/* Flush pending messages and be sure that the sending of notifications has stopped. */
	f_sleep(1.0);
	L1CTL.clear;

	/* NCH must not be received. */
	T.start(2.0);
	alt {
	[] L1CTL.receive(tr_L1CTL_DATA_IND(t_RslChanNr_PCH_AGCH(0), ?, notif_nch)) {
		T.stop;
		setverdict(fail, "Received unexpected NOTIFICATION/NCH.");
		}
	[] L1CTL.receive { repeat; }
	[] T.timeout {
		log("Not received NOTIFICATION/NCH. (as expected)");
		setverdict(pass);
		}
	}

	Misc_Helpers.f_shutdown(__BFILE__, __LINE__);
}

/* Sub function to clean up MS and BTS. */
private function f_vgcs_cleanup() runs on ConnHdlr
{
	/* Cleanup L1CTL. */
	f_L1CTL_RESET(L1CTL);
	f_l1_tune(L1CTL);

	/* Cleanup VGCS Channel. */
	f_rsl_chan_deact();
}

/* A VGCS channel is activated. The BSC sends UPLINK FREE message and UPLINK BUSY message.
 * When the UPLINK FREE message is sent, the MS is expected to receive several UPLINK FREE messages.
 * Then the UPLINK BUSY message is sent, the MS is expected to receive one UPLINK BUSY message.
 */
private function f_TC_vgcs_uplink_free_and_busy(charstring id) runs on ConnHdlr
{
	var octetstring uplink_free := '082B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B'O;
	var octetstring uplink_busy := '062A'O;

	f_l1_tune(L1CTL);
	RSL.clear;

	/* Activate channel on the BTS side */
	log("Activating VGCS channel.");
	f_rsl_chan_act(g_pars.chan_mode);

	/* enable dedicated mode */
	f_l1ctl_est_dchan(L1CTL, g_pars);

	/* Send one UPLINK FREE message and expect them to be repeated. */
	log("Send UPLINK FREE.");
	RSL.send(ts_RSL_UNITDATA_REQ(g_chan_nr, ts_RslLinkID_DCCH(0), uplink_free));
	for (var integer i := 0; i < 20; i := i + 1) {
		f_l1_exp_lapdm(tr_LAPDm_Bter_UI(uplink_free));
		log("Received UPLINK FREE.");
	}

	/* Send one UPLINK BUSY message and expect it to be received. */
	log("Send UPLINK BUSY.");
	RSL.send(ts_RSL_UNITDATA_REQ(g_chan_nr, ts_RslLinkID_DCCH(0), uplink_busy));
	f_l1_exp_lapdm(tr_LAPDm_UI(0, cr_MT_CMD, uplink_busy));
	log("Received UPLINK BUSY.");

	/* Deactivate and cleanup. */
	f_vgcs_cleanup();
}
testcase TC_vgcs_uplink_free_and_busy() runs on test_CT
{
	var template RSL_IE_ChannelMode ch_mode;
	var ConnHdlrPars pars;
	var ConnHdlr vc_conn;

	f_init();

	ch_mode := ts_RSL_ChanMode(RSL_CHRT_TCH_F_GROUP, RSL_CMOD_SP_GSM1);
	pars := valueof(t_Pars(t_RslChanNr_Bm(1), ch_mode));
	vc_conn := f_start_handler(refers(f_TC_vgcs_uplink_free_and_busy), pars);
	vc_conn.done;

	Misc_Helpers.f_shutdown(__BFILE__, __LINE__);
}

/* Sub function to test talker detect. */
private function f_vgcs_talker_detect() runs on ConnHdlr
{
	var octetstring uplink_free := '082B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B2B'O;
	var octetstring uplink_access := 'C0'O;
	var template octetstring uplink_grant := '0609C0*'O;
	var RSL_Message rm;
	var GsmFrameNumber fn;

	f_l1_tune(L1CTL);
	RSL.clear;

	/* Activate channel on the BTS side. */
	log("Activating VGCS channel.");
	f_rsl_chan_act(g_pars.chan_mode);

	/* Enable dedicated mode. */
	f_l1ctl_est_dchan(L1CTL, g_pars);

	/* Send one UPLINK FREE message and expect them to be repeated. */
	log("Send UPLINK FREE.");
	RSL.send(ts_RSL_UNITDATA_REQ(g_chan_nr, ts_RslLinkID_DCCH(0), uplink_free));
	f_l1_exp_lapdm(tr_LAPDm_Bter_UI(uplink_free));
	log("Received UPLINK FREE.");

	/* Send UPLINK ACCESS on VGCS channel. */
	log("Send UPLINK ACCESS.");
	fn := f_L1CTL_RACH(L1CTL, oct2int(uplink_access), chan_nr := g_pars.chan_nr);

	/* Receive UPLINK GRANT by the MS. */
	f_l1_exp_lapdm(tr_LAPDm_UI(0, cr_MT_CMD, uplink_grant));
	log("Received VGCS UPLINK GRANT.");

	/* Wait for talker detection. */
	timer T := 1.0;
	T.start;
	alt {
	[] RSL.receive(tr_RSL_TALKER_DET(g_pars.chan_nr, ?)) -> value rm {
		log("RSL Talker Detect has been detected: ", rm);
		T.stop;
		}
	[] RSL.receive(tr_RSL_CHAN_RQD(?, ?, ?, ?)) -> value rm {
		setverdict(fail, "RSL_CHAN_RQD was not expected: ", rm);
		T.stop;
		}
	[] RSL.receive { repeat; }
	[] T.timeout {
		setverdict(fail, "Timeout waiting for RSL Talker Detect.");
		}
	}
}

/* A VGCS channel is activated. The BSC sends UPLINK FREE message. The MS sends RACH on VGCS channel.
 * The MS receives VGCS UPLINK GRAND, but does not respond to it. It is expeced that the BSC receivce RSL CONN FAIL.
 */
private function f_TC_vgcs_talker_fail(charstring id) runs on ConnHdlr
{
	var RSL_Message rm;

	/* Perform link establishment and talker detection. */
	f_vgcs_talker_detect();

	/* Leave dedicated channel, to force link timeout. */
	f_L1CTL_RESET(L1CTL);
	f_l1_tune(L1CTL);

	/* Wait for link timeout. */
	timer T := 40.0;
	T.start;
	alt {
	[] RSL.receive(tr_RSL_CONN_FAIL_IND(g_pars.chan_nr, ?)) -> value rm {
		log("RSL Conn Fail Ind has been detected as expected: ", rm);
		T.stop;
		}
	[] RSL.receive { repeat; }
	[] T.timeout {
		setverdict(fail, "Timeout waiting for RSL Conn Fail Ind.");
		}
	}

	/* Deactivate and cleanup. */
	f_vgcs_cleanup();
}
testcase TC_vgcs_talker_fail() runs on test_CT
{
	var template RSL_IE_ChannelMode ch_mode;
	var ConnHdlrPars pars;
	var ConnHdlr vc_conn;

	f_init();

	ch_mode := ts_RSL_ChanMode(RSL_CHRT_TCH_F_GROUP, RSL_CMOD_SP_GSM1);
	pars := valueof(t_Pars(t_RslChanNr_Bm(1), ch_mode));
	pars.t_guard := 60.0;
	vc_conn := f_start_handler(refers(f_TC_vgcs_talker_fail), pars);
	vc_conn.done;

	Misc_Helpers.f_shutdown(__BFILE__, __LINE__);
}

control {
	execute( TC_vbs_notification() );
	execute( TC_vgcs_uplink_free_and_busy() );
	execute( TC_vgcs_talker_fail() );

}

}