/* TITAN REW encode/decode definitions for 3GPP TS 44.060 RLC/MAC Blocks */

/* (C) 2017-2018 Harald Welte <laforge@gnumonks.org>
 * (C) 2020 by sysmocom s.f.m.c. GmbH <info@sysmocom.de>
 * All rights reserved.
 *
 * Released under the terms of GNU General Public License, Version 2 or
 * (at your option) any later version.
 *
 * SPDX-License-Identifier: GPL-2.0-or-later
 */

module RLCMAC_Templates {
	import from General_Types all;
	import from Osmocom_Types all;
	import from GSM_Types all;
	import from RLCMAC_CSN1_Types all;
	import from RLCMAC_CSN1_Templates all;
	import from RLCMAC_Types all;

	/* TS 44.060 10.4.5 */
	function f_rrbp_fn_delay(MacRrbp rrbp) return uint32_t {
		select (rrbp) {
		case (RRBP_Nplus13_mod_2715648) { return 13; }
		case (RRBP_Nplus17_or_18_mod_2715648) { return 17; }
		case (RRBP_Nplus21_or_22_mod_2715648) { return 21;  }
		case (RRBP_Nplus26_mod_2715648) { return 26; }
		}
		return 0;
	}

	function f_rrbp_ack_fn(uint32_t current_fn, MacRrbp rrbp)
	return uint32_t {
		return (current_fn + f_rrbp_fn_delay(rrbp)) mod 2715648;
	}

	function f_rlcmac_mcs2headertype(CodingScheme mcs) return EgprsHeaderType {
		select (mcs) {
		case (MCS_0) { return RLCMAC_HDR_TYPE_3; }
		case (MCS_1) { return RLCMAC_HDR_TYPE_3; }
		case (MCS_2) { return RLCMAC_HDR_TYPE_3; }
		case (MCS_3) { return RLCMAC_HDR_TYPE_3; }
		case (MCS_4) { return RLCMAC_HDR_TYPE_3; }
		case (MCS_5) { return RLCMAC_HDR_TYPE_2; }
		case (MCS_6) { return RLCMAC_HDR_TYPE_2; }
		case (MCS_7) { return RLCMAC_HDR_TYPE_1; }
		case (MCS_8) { return RLCMAC_HDR_TYPE_1; }
		case (MCS_9) { return RLCMAC_HDR_TYPE_1; }
		}
		return RLCMAC_HDR_TYPE_3;
	}

	function f_rlcmac_cs_mcs2block_len(CodingScheme cs_mcs) return uint32_t {
		select (cs_mcs) {
		case (CS_1) { return 23; }
		case (CS_2) { return 34; }
		case (CS_3) { return 40; }
		case (CS_4) { return 54; }
		case (MCS_1) { return 27; }
		case (MCS_2) { return 33; }
		case (MCS_3) { return 42; }
		case (MCS_4) { return 49; }
		case (MCS_5) { return 61; }
		case (MCS_6) { return 79; }
		case (MCS_7) { return 119; }
		case (MCS_8) { return 143; }
		case (MCS_9) { return 155; }
		}
		return 0;
	}

	function f_rlcmac_block_len2cs_mcs(uint32_t len) return CodingScheme {
		select (len) {
			case (23) { return CS_1; }
			case (34) { return CS_2; }
			case (40) { return CS_3; }
			case (54) { return CS_4; }
			case (27) { return MCS_1; }
			case (33) { return MCS_2; }
			case (42) { return MCS_3; }
			case (49) { return MCS_4; }
			case (60) { return MCS_5; }
			case (61) { return MCS_5; }
			case (78) { return MCS_6; }
			case (79) { return MCS_6; }
			case (118) { return MCS_7; }
			case (119) { return MCS_7; }
			case (142) { return MCS_8; }
			case (143) { return MCS_8; }
			case (154) { return MCS_9; }
			case (155) { return MCS_9; }
		}
		return CS_1;
	}

	/* Coding and Puncturing Scheme indicator field for Header type 1 in EGPRS TBF or EC TBF or downlink EGPRS2 TBF */
	function f_rlcmac_cps_htype1_to_mcs(uint3_t cps) return CodingScheme {
		var CodingSchemeArray egprs_Header_type1_coding_puncturing_scheme_to_mcs := {
			MCS_9 /* 0x00, "(MCS-9/P1 ; MCS-9/P1)" */,
			MCS_9 /* 0x01, "(MCS-9/P1 ; MCS-9/P2)" */,
			MCS_9 /* 0x02, "(MCS-9/P1 ; MCS-9/P3)" */,
			MCS_0 /* 0x03, "reserved" */,
			MCS_9 /* 0x04, "(MCS-9/P2 ; MCS-9/P1)" */,
			MCS_9 /* 0x05, "(MCS-9/P2 ; MCS-9/P2)" */,
			MCS_9 /* 0x06, "(MCS-9/P2 ; MCS-9/P3)" */,
			MCS_0 /* 0x07, "reserved" */,
			MCS_9 /* 0x08, "(MCS-9/P3 ; MCS-9/P1)" */,
			MCS_9 /* 0x09, "(MCS-9/P3 ; MCS-9/P2)" */,
			MCS_9 /* 0x0A, "(MCS-9/P3 ; MCS-9/P3)" */,
			MCS_8 /* 0x0B, "(MCS-8/P1 ; MCS-8/P1)" */,
			MCS_8 /* 0x0C, "(MCS-8/P1 ; MCS-8/P2)" */,
			MCS_8 /* 0x0D, "(MCS-8/P1 ; MCS-8/P3)" */,
			MCS_8 /* 0x0E, "(MCS-8/P2 ; MCS-8/P1)" */,
			MCS_8 /* 0x0F, "(MCS-8/P2 ; MCS-8/P2)" */,
			MCS_8 /* 0x10, "(MCS-8/P2 ; MCS-8/P3)" */,
			MCS_8 /* 0x11, "(MCS-8/P3 ; MCS-8/P1)" */,
			MCS_8 /* 0x12, "(MCS-8/P3 ; MCS-8/P2)" */,
			MCS_8 /* 0x13, "(MCS-8/P3 ; MCS-8/P3)" */,
			MCS_7 /* 0x14, "(MCS-7/P1 ; MCS-7/P1)" */,
			MCS_7 /* 0x15, "(MCS-7/P1 ; MCS-7/P2)" */,
			MCS_7 /* 0x16, "(MCS-7/P1 ; MCS-7/P3)" */,
			MCS_7 /* 0x17, "(MCS-7/P2 ; MCS-7/P1)" */,
			MCS_7 /* 0x18, "(MCS-7/P2 ; MCS-7/P2)" */,
			MCS_7 /* 0x19, "(MCS-7/P2 ; MCS-7/P3)" */,
			MCS_7 /* 0x1A, "(MCS-7/P3 ; MCS-7/P1)" */,
			MCS_7 /* 0x1B, "(MCS-7/P3 ; MCS-7/P2)" */,
			MCS_7 /* 0x1C, "(MCS-7/P3 ; MCS-7/P3)" */,
			MCS_0 /* 0x1D, "reserved" */,
			MCS_0 /* 0x1E, "reserved" */,
			MCS_0 /* 0x1F, "reserved" */
		};
		return egprs_Header_type1_coding_puncturing_scheme_to_mcs[cps];
	}

	/* Coding and Puncturing Scheme indicator field for Header type 2 in (EC-)EGPRS TBF or uplink EGPRS2-A TBF */
	function f_rlcmac_cps_htype2_to_mcs(uint3_t cps) return CodingScheme {
		var CodingSchemeArray egprs_Header_type2_coding_puncturing_scheme_to_mcs := {
			MCS_6 /* {0x00, "MCS-6/P1"} */,
			MCS_6 /* {0x01, "MCS-6/P2"} */,
			MCS_6 /* {0x02, "MCS-6/P1 with 6 octet padding"} */,
			MCS_6 /* {0x03, "MCS-6/P2 with 6 octet padding "} */,
			MCS_5 /* {0x04, "MCS-5/P1"} */,
			MCS_5 /* {0x05, "MCS-5/P2"} */,
			MCS_5 /* {0x06, "MCS-6/P1 with 10 octet padding "} */,
			MCS_5 /* {0x07, "MCS-6/P2 with 10 octet padding "} */
		 };
		 return egprs_Header_type2_coding_puncturing_scheme_to_mcs[cps];
	}

	/* Coding and Puncturing Scheme indicator field for Header type 3 */
	function f_rlcmac_cps_htype3_to_mcs(uint3_t cps) return CodingScheme {
		var CodingSchemeArray egprs_Header_type3_coding_puncturing_scheme_to_mcs := {
			MCS_4 /* {0x00, "MCS-4/P1"} */,
			MCS_4 /* {0x01, "MCS-4/P2"} */,
			MCS_4 /* {0x02, "MCS-4/P3"} */,
			MCS_3 /* {0x03, "MCS-3/P1"} */,
			MCS_3 /* {0x04, "MCS-3/P2"} */,
			MCS_3 /* {0x05, "MCS-3/P3"} */,
			MCS_3 /* {0x06, "MCS-3/P1 with padding"} */,
			MCS_3 /* {0x07, "MCS-3/P2 with padding"} */,
			MCS_3 /* {0x08, "MCS-3/P3 with padding"} */,
			MCS_2 /* {0x09, "MCS-2/P1"} */,
			MCS_2 /* {0x0A, "MCS-2/P2"} */,
			MCS_1 /* {0x0B, "MCS-1/P1"} */,
			MCS_1 /* {0x0C, "MCS-1/P2"} */,
			MCS_2 /* {0x0D, "MCS-2/P1 with padding"} */,
			MCS_2 /* {0x0E, "MCS-2/P2 with padding"} */,
			MCS_0 /* {0x0F, "MCS-0"} */
		};
		return egprs_Header_type3_coding_puncturing_scheme_to_mcs[cps];
	}

	function f_rlcmac_cps_htype_to_mcs(uint3_t cps, EgprsHeaderType htype) return CodingScheme {
		select (htype) {
		case (RLCMAC_HDR_TYPE_1) { return f_rlcmac_cps_htype1_to_mcs(cps); }
		case (RLCMAC_HDR_TYPE_2) { return f_rlcmac_cps_htype2_to_mcs(cps); }
		case (RLCMAC_HDR_TYPE_3) { return f_rlcmac_cps_htype3_to_mcs(cps); }
		}
		//TODO: return error here.
		return CS_1;
	}

	function f_rlcmac_mcs_to_cps_htype1(CodingScheme mcs, uint2_t part, boolean with_padding) return uint5_t {
		//TODO: implement similar to f_rlcmac_mcs_to_cps_htype3()
		//TODO: return error here.
		return 0;
	}

	function f_rlcmac_mcs_to_cps_htype2(CodingScheme mcs, uint2_t part, boolean with_padding) return uint5_t {
		//TODO: implement similar to f_rlcmac_mcs_to_cps_htype3()
		//TODO: return error here.
		return 0;
	}

	function f_rlcmac_mcs_to_cps_htype3(CodingScheme mcs, uint2_t part, boolean with_padding) return uint5_t {
		select (mcs) {
		case (MCS_4) {
				select (part) {
				case (1) { return 0; /* {0x00, "MCS-4/P1"} */ }
				case (2) { return 1; /* {0x01, "MCS-4/P2"} */ }
				case (3) { return 2; /* {0x01, "MCS-4/P2"} */ }
				}
			}
		case (MCS_3) {
				if (not with_padding) {
					select (part) {
					case (1) { return 3; /* {0x03, "MCS-3/P1"} */ }
					case (2) { return 4; /* {0x04, "MCS-3/P2"} */ }
					case (3) { return 5; /* {0x05, "MCS-3/P3"} */ }
					}
				} else {
					select (part) {
					case (1) { return 6; /* {0x06, "MCS-3/P1 with padding"} */ }
					case (2) { return 7; /* {0x07, "MCS-3/P2 with padding"} */ }
					case (3) { return 8; /* {0x08, "MCS-3/P3 with padding"} */ }
					}
				}
			}
		case (MCS_2) {
				if (not with_padding) {
					select (part) {
					case (1) { return 9; /* {0x09, "MCS-2/P1"} */ }
					case (2) { return 10; /* {0x0A, "MCS-2/P2"} */ }
					}
				} else {
					select (part) {
					case (1) { return 13; /* {0x0D, "MCS-2/P1 with padding"} */ }
					case (2) { return 14; /* {0x0E, "MCS-2/P2 with padding"} */}
					}
				}
			}
		case (MCS_1) {
				select (part) {
				case (1) { return 11; /* {0x0B, "MCS-1/P1"} */ }
				case (2) { return 12; /* {0x0C, "MCS-1/P2"} */ }
				}
			}
		case (MCS_0) { return 15;  /* {0x0F, "MCS-0"} */ }
		}
		//TODO: return error here.
		return 0;
	}

	function f_rlcmac_mcs_to_cps(CodingScheme mcs, uint2_t part, boolean with_padding := false) return uint5_t {

		var EgprsHeaderType htype := f_rlcmac_mcs2headertype(mcs);
		select (htype) {
		case (RLCMAC_HDR_TYPE_1) { return f_rlcmac_mcs_to_cps_htype1(mcs, part, with_padding); }
		case (RLCMAC_HDR_TYPE_2) { return f_rlcmac_mcs_to_cps_htype2(mcs, part, with_padding); }
		case (RLCMAC_HDR_TYPE_3) { return f_rlcmac_mcs_to_cps_htype3(mcs, part, with_padding); }
		}
		//TODO: return error here.
		return 0;
	}

	template (value) RlcmacUlBlock ts_RLC_UL_CTRL_ACK(RlcmacUlCtrlMsg ctrl,
							MacPayloadType pt := MAC_PT_RLCMAC_NO_OPT,
							boolean retry := false) := {
		ctrl := {
			mac_hdr := {
				payload_type := pt,
				spare := '00000'B,
				retry := retry
			},
			payload := ctrl
		}
	}

	/* Send Template for Downlink ACK/NACK */
	template RlcmacUlBlock ts_RLCMAC_DL_ACK_NACK(template uint5_t tfi, AckNackDescription andesc, boolean retry := false) := {
		ctrl := {
			mac_hdr := {
				payload_type := MAC_PT_RLCMAC_NO_OPT,
				spare := '00000'B,
				retry := retry
			},
			payload := {
				msg_type := PACKET_DL_ACK_NACK,
				u := {
					dl_ack_nack := {
						dl_tfi := tfi,
						ack_nack_desc := andesc,
						chreq_desc_presence := '0'B,
						chreq_desc := omit,
						ch_qual_rep := c_ChQualRep_default
					}
				}
			}
		}
	}

	/* Template for uplink Data block */
	template RlcmacUlBlock t_RLCMAC_UL_DATA(template uint5_t tfi, template uint4_t cv, template uint7_t bsn,
						template LlcBlocks blocks := {}, template boolean stall := false) := {
		data := {
			mac_hdr := {
				payload_type := MAC_PT_RLC_DATA,
				countdown := cv,
				stall_ind := false,
				retry := false,
				spare := '0'B,
				pfi_ind := false,
				tfi := tfi,
				tlli_ind := false,
				bsn := bsn,
				e := false
			},
			tlli := omit,
			pfi := omit,
			blocks := blocks
		}
	}
	template RlcmacUlBlock t_RLCMAC_UL_DATA_TLLI(template uint5_t tfi, template uint4_t cv, template uint7_t bsn,
						     template LlcBlocks blocks := {}, template boolean stall := false, template GprsTlli tlli) := {
		data := {
			mac_hdr := {
				payload_type := MAC_PT_RLC_DATA,
				countdown := cv,
				stall_ind := false,
				retry := false,
				spare := '0'B,
				pfi_ind := false,
				tfi := tfi,
				tlli_ind := true,
				bsn := bsn,
				e := false
			},
			tlli := tlli,
			pfi := omit,
			blocks := blocks
		}
	}

	/* Template for uplink Data block */
	template RlcmacUlBlock t_RLCMAC_UL_EGPRS_DATA(CodingScheme mcs,
						      template uint5_t tfi, template uint4_t cv,
						      template uint11_t bsn1, template EgprsLlcBlocks blocks := {}) := {
		data_egprs := {
			mac_hdr := {
				header_type := f_rlcmac_mcs2headertype(mcs),
				tfi := tfi,
				countdown := cv,
				foi_si := '0'B,
				r_ri := '0'B,
				bsn1 := bsn1,
				cps := f_rlcmac_mcs_to_cps(mcs, 1, false),
				pfi_ind := false,
				rsb := '0'B,
				spb := '00'B
			},
			tlli_ind := false,
			e := false,
			tlli := omit,
			pfi := omit,
			blocks := blocks
		}
	}

	template DlMacHeader t_RLCMAC_DlMacH(template (present) MacPayloadType pt,
					     template (present) boolean rrbp_valid,
					     template (present) MacRrbp rrbp,
					     template (present) uint3_t usf) := {
		payload_type := pt,
		rrbp := rrbp,
		rrbp_valid := rrbp_valid,
		usf := usf
	}

	template RlcmacDlBlock tr_RLCMAC_DUMMY_CTRL(template uint3_t usf := ?, template PageMode page_mode := ?) := {
		ctrl := {
			mac_hdr := {
				payload_type := (MAC_PT_RLCMAC_NO_OPT, MAC_PT_RLCMAC_OPT),
				rrbp:= ?,
				rrbp_valid := ?,
				usf := usf
			},
			opt := *,
			payload := {
				msg_type := PACKET_DL_DUMMY_CTRL,
				u := {
					dl_dummy := {
						page_mode := page_mode,
						persistence_levels_present := ?,
						persistence_levels := *
					}
				}
			}
		}
	}

	template RlcmacDlBlock tr_RLCMAC_DL_PACKET_ASS(template uint3_t usf := ?) := {
		ctrl := {
			mac_hdr := {
				payload_type := (MAC_PT_RLCMAC_NO_OPT, MAC_PT_RLCMAC_OPT),
				rrbp:= ?,
				rrbp_valid := ?,
				usf := usf
			},
			opt := *,
			payload := {
				msg_type := PACKET_DL_ASSIGNMENT,
				u := {
					dl_assignment := {
						page_mode := ?,
						pres1 := ?,
						persistence_levels := *,
						tfi_or_tlli := ?
					}
				}
			}
		}
	}

	template RlcmacDlBlock tr_RLCMAC_UL_PACKET_ASS(template uint3_t usf := ?) := {
		ctrl := {
			mac_hdr := {
				payload_type := (MAC_PT_RLCMAC_NO_OPT, MAC_PT_RLCMAC_OPT),
				rrbp:= ?,
				rrbp_valid := ?,
				usf := usf
			},
			opt := *,
			payload := {
				msg_type := PACKET_UL_ASSIGNMENT,
				u := {
					ul_assignment := {
						page_mode := ?,
						persistence_levels_present := ?,
						persistence_levels := *,
						identity := ?,
						is_egprs := ?,  /* msg escape */
						gprs := *
					}
				}
			}
		}
	}


	/* Receive Template for Uplink ACK/NACK */
	template RlcmacDlBlock tr_RLCMAC_UL_ACK_NACK(template uint5_t ul_tfi, template GprsTlli tlli := ?) := {
		ctrl := {
			mac_hdr := {
				payload_type := (MAC_PT_RLCMAC_NO_OPT, MAC_PT_RLCMAC_OPT),
				rrbp:= ?,
				rrbp_valid := ?,
				usf := ?
			},
			opt := *,
			payload := {
				msg_type := PACKET_UL_ACK_NACK,
				u := {
					ul_ack_nack := {
						page_mode := ?,
						msg_excape := ?,
						uplink_tfi := ul_tfi,
						is_egprs := '0'B,
						gprs := {
							ch_coding_cmd := ?,
							ack_nack_desc := ?,
							cont_res_tlli_present := ?,
							cont_res_tlli := tlli,
							pkt_ta_present := ?,
							pkt_ta := *,
							pwr_ctrl_present := ?,
							pwr_ctrl := *
						}
					}
				}
			}
		}
	}

	template RlcmacDlBlock tr_RLCMAC_PACKET_PAG_REQ(template uint3_t usf := ?) := {
		ctrl := {
			mac_hdr := {
				payload_type := MAC_PT_RLCMAC_NO_OPT,
				rrbp:= ?,
				rrbp_valid := ?,
				usf := usf
			},
			opt := *,
			payload := {
				msg_type := PACKET_PAGING_REQUEST,
				u := {
					paging := {
						page_mode := ?,
						persistence_levels_present := ?,
						persistence_levels := *,
						nln_present := ?,
						nln := *,
						repeated_pageinfo_present := ?,
						repeated_pageinfo := *
					}
				}
			}
		}
	}

	/* Either GPRS or EGPRS data block with arbitrary contents */
	template RlcmacDlBlock tr_RLCMAC_DATA := (tr_RLCMAC_DATA_GPRS, tr_RLCMAC_DATA_EGPRS);

	template RlcmacDlBlock tr_RLCMAC_DATA_GPRS(template (present) boolean rrbp_valid := ?,
						   template (present) MacRrbp rrbp := ?,
						   template (present) uint3_t usf := ?) := {
		data := {
			mac_hdr := {
				mac_hdr := {
					payload_type := MAC_PT_RLC_DATA,
					rrbp := rrbp,
					rrbp_valid := rrbp_valid,
					usf := usf
				},
				hdr_ext := ?
			},
			blocks := ?
		}
	}

	template RlcmacDlBlock tr_RLCMAC_DATA_EGPRS := {
		data_egprs := {
			mac_hdr := ?,
			fbi := ?,
			e := ?,
			blocks := ?
		}
	}

	/* Template for Uplink MAC Control Header */
	template UlMacCtrlHeader t_RLCMAC_UlMacCtrlH(template MacPayloadType pt, template boolean retry := false) := {
		payload_type := pt,
		spare := '00000'B,
		retry := retry
	}

	/* Template for Uplink Control ACK */
	template RlcmacUlBlock ts_RLCMAC_CTRL_ACK(GprsTlli tlli, CtrlAck ack := MS_RCVD_TWO_RLC_SAME_RTI_DIFF_RBSN) := {
		ctrl := {
			mac_hdr := t_RLCMAC_UlMacCtrlH(MAC_PT_RLCMAC_NO_OPT),
			payload := {
				msg_type := PACKET_CONTROL_ACK,
				u := {
					ctrl_ack := {
						tlli := tlli,
						ctrl_ack := ack
					}
				}
			}
		}
	}

	/* Template for a LlcBlock (part of a LLC frame inside RlcMac?lDataBlock */
	template LlcBlock t_RLCMAC_LLCBLOCK(octetstring data, boolean more := false, boolean e := true) := {
		/* let encoder figure out the header */
		hdr := omit,
		payload := data
	}

	/* Template for a LlcBlock (part of a LLC frame inside RlcMacEgprs?lDataBlock */
	template EgprsLlcBlock t_RLCMAC_LLCBLOCK_EGPRS(octetstring data, boolean e := true) := {
		/* let encoder figure out the header */
		hdr := omit,
		payload := data
	}

} with { encode "RAW"; variant "FIELDORDER(msb)" }