/* TETRA upper MAC layer main routine, above TMV-SAP */

/* (C) 2011 by Harald Welte <laforge@gnumonks.org>
 * All Rights Reserved
 *
 * 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/>.
 *
 */

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

#include <osmocore/utils.h>

#include "tetra_common.h"
#include "tetra_prim.h"
#include "tetra_upper_mac.h"
#include "tetra_mac_pdu.h"
#include "tetra_mle_pdu.h"
#include "tetra_mm_pdu.h"
#include "tetra_gsmtap.h"

static void rx_bcast(struct tetra_tmvsap_prim *tmvp)
{
	struct tmv_unitdata_param *tup = &tmvp->u.unitdata;
	struct tetra_si_decoded sid;
	uint32_t dl_freq, ul_freq;
	int i;

	memset(&sid, 0, sizeof(sid));
	macpdu_decode_sysinfo(&sid, tup->mac_block);

	dl_freq = tetra_dl_carrier_hz(sid.freq_band,
				      sid.main_carrier,
				      sid.freq_offset);

	ul_freq = tetra_ul_carrier_hz(sid.freq_band,
				      sid.main_carrier,
				      sid.freq_offset,
				      sid.duplex_spacing,
				      sid.reverse_operation);

	printf("BNCH SYSINFO (DL %u Hz, UL %u Hz), service_details 0x%04x ",
		dl_freq, ul_freq, sid.mle_si.bs_service_details);
	if (sid.cck_valid_no_hf)
		printf("CCK ID %u", sid.cck_id);
	else
		printf("Hyperframe %u", sid.hyperframe_number);
	printf("\n");
	for (i = 0; i < 12; i++)
		printf("\t%s: %u\n", tetra_get_bs_serv_det_name(1 << i),
			sid.mle_si.bs_service_details & (1 << i) ? 1 : 0);

}

const char *tetra_alloc_dump(const struct tetra_chan_alloc_decoded *cad)
{
	static char buf[64];
	char *cur = buf;

	cur += sprintf(cur, "%s (TN%u/%s/%uHz)",
		tetra_get_alloc_t_name(cad->type), cad->timeslot,
		tetra_get_ul_dl_name(cad->ul_dl),
		tetra_dl_carrier_hz(cad->ext_carr.freq_band, cad->carrier_nr,
				    cad->ext_carr.freq_offset));

	return buf;
}

static int rx_tm_sdu(uint8_t *bits, unsigned int len)
{
	uint8_t mle_pdisc = bits_to_uint(bits, 3);

	printf("TM-SDU(%s): %s", tetra_get_mle_pdisc_name(mle_pdisc),
		bitdump(bits, len));
	switch (mle_pdisc) {
	case TMLE_PDISC_MM:
		printf(" %s", tetra_get_mm_pdut_name(bits_to_uint(bits+3, 4), 0));
		break;
	default:
		break;
	}
	return len;
}

static void rx_resrc(struct tetra_tmvsap_prim *tmvp)
{
	struct tmv_unitdata_param *tup = &tmvp->u.unitdata;
	struct tetra_resrc_decoded rsd;
	int tmpdu_offset;

	memset(&rsd, 0, sizeof(rsd));
	tmpdu_offset = macpdu_decode_resource(&rsd, tup->mac_block);

	printf("RESOURCE Encr=%u, Length_ind=%u Addr=%s ",
		rsd.encryption_mode, rsd.length_ind,
		tetra_addr_dump(&rsd.addr));

	if (rsd.chan_alloc_pres)
		printf("ChanAlloc=%s ", tetra_alloc_dump(&rsd.cad));

	if (rsd.length_ind && rsd.encryption_mode == 0) {
		int len_bits = rsd.length_ind*8;
		if (tup->mac_block + tmpdu_offset + len_bits >
					tup->mac_block + tup->mac_block_len)
			len_bits = tup->mac_block_len - tmpdu_offset;
		rx_tm_sdu(tup->mac_block + tmpdu_offset, len_bits);
	}

	printf("\n");
}

static void dump_access(struct tetra_access_field *acc, unsigned int num)
{
	printf("ACCESS%u: %c/%u ", num, 'A'+acc->access_code, acc->base_frame_len);
}

static void rx_aach(struct tetra_tmvsap_prim *tmvp)
{
	struct tmv_unitdata_param *tup = &tmvp->u.unitdata;
	struct tetra_acc_ass_decoded aad;

	printf("ACCESS-ASSIGN PDU: ");

	memset(&aad, 0, sizeof(aad));
	macpdu_decode_access_assign(&aad, tup->mac_block,
				    tup->tdma_time.fn == 18 ? 1 : 0);

	if (aad.pres & TETRA_ACC_ASS_PRES_ACCESS1)
		dump_access(&aad.access[0], 1);
	if (aad.pres & TETRA_ACC_ASS_PRES_ACCESS2)
		dump_access(&aad.access[1], 2);
	if (aad.pres & TETRA_ACC_ASS_PRES_DL_USAGE)
		printf("DL_USAGE: %s ", tetra_get_dl_usage_name(aad.dl_usage));
	if (aad.pres & TETRA_ACC_ASS_PRES_UL_USAGE)
		printf("UL_USAGE: %s ", tetra_get_ul_usage_name(aad.ul_usage));

	printf("\n");
}

static int rx_tmv_unitdata_ind(struct tetra_tmvsap_prim *tmvp)
{
	struct tmv_unitdata_param *tup = &tmvp->u.unitdata;
	uint8_t pdu_type = bits_to_uint(tup->mac_block, 2);
	const char *pdu_name;
	struct msgb *gsmtap_msg;

	if (tup->lchan == TETRA_LC_BSCH)
		pdu_name = "SYNC";
	else if (tup->lchan == TETRA_LC_AACH)
		pdu_name = "ACCESS-ASSIGN";
	else {
		pdu_type = bits_to_uint(tup->mac_block, 2);
		pdu_name = tetra_get_macpdu_name(pdu_type);
	}

	printf("TMV-UNITDATA.ind %s %s CRC=%u %s\n",
		tetra_tdma_time_dump(&tup->tdma_time),
		tetra_get_lchan_name(tup->lchan),
		tup->crc_ok, pdu_name);

	if (!tup->crc_ok)
		return 0;

	gsmtap_msg = tetra_gsmtap_makemsg(&tup->tdma_time, tup->lchan, tup->tdma_time.tn,
					  /* FIXME: */ 0, 0, 0, tup->mac_block, tup->mac_block_len);
	if (gsmtap_msg)
		tetra_gsmtap_sendmsg(gsmtap_msg);

	switch (tup->lchan) {
	case TETRA_LC_AACH:
		rx_aach(tmvp);
		break;
	case TETRA_LC_BNCH:
	case TETRA_LC_UNKNOWN:
	case TETRA_LC_SCH_F:
		if (pdu_type == TETRA_PDU_T_BROADCAST)
			rx_bcast(tmvp);
		if (pdu_type == TETRA_PDU_T_MAC_RESOURCE)
			rx_resrc(tmvp);
		break;
	}
	if (pdu_type == TETRA_PDU_T_MAC_FRAG_END) {
		if (tup->mac_block[3] == TETRA_MAC_FRAGE_FRAG)
			rx_tm_sdu(tup->mac_block+4, 100 /*FIXME*/);
	}

	return 0;
}

int upper_mac_prim_recv(struct osmo_prim_hdr *op, void *priv)
{
	struct tetra_tmvsap_prim *tmvp;
	int rc;

	switch (op->sap) {
	case TETRA_SAP_TMV:
		tmvp = (struct tetra_tmvsap_prim *) op;
		rc = rx_tmv_unitdata_ind(tmvp);
		break;
	default:
		printf("primitive on unknown sap\n");
		break;
	}

	free(op);

	return rc;
}