// /***************************************************************************
// The Disc Image Chef
// ----------------------------------------------------------------------------
//
// Filename       : Structs.cs
// Author(s)      : Natalia Portillo <claunia@claunia.com>
//
// Component      : FreeBSD direct device access.
//
// --[ Description ] ----------------------------------------------------------
//
//     Contains structures necessary for directly interfacing devices under
//     FreeBSD.
//
// --[ License ] --------------------------------------------------------------
//
//     This library is free software; you can redistribute it and/or modify
//     it under the terms of the GNU Lesser General Public License as
//     published by the Free Software Foundation; either version 2.1 of the
//     License, or (at your option) any later version.
//
//     This library 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
//     Lesser General Public License for more details.
//
//     You should have received a copy of the GNU Lesser General Public
//     License along with this library; if not, see <http://www.gnu.org/licenses/>.
//
// ----------------------------------------------------------------------------
// Copyright © 2011-2017 Natalia Portillo
// ****************************************************************************/

using System;
using System.Runtime.InteropServices;

namespace DiscImageChef.Devices.FreeBSD
{
    struct ata_cmd
    {
        public CamAtaIoFlags flags;
        public byte command;
        public byte features;
        public byte lba_low;
        public byte lba_mid;
        public byte lba_high;
        public byte device;
        public byte lba_low_exp;
        public byte lba_mid_exp;
        public byte lba_high_exp;
        public byte features_exp;
        public byte sector_count;
        public byte sector_count_exp;
        public byte control;
    }

    struct ata_res
    {
        public CamAtaIoFlags flags;
        public byte status;
        public byte error;
        public byte lba_low;
        public byte lba_mid;
        public byte lba_high;
        public byte device;
        public byte lba_low_exp;
        public byte lba_mid_exp;
        public byte lba_high_exp;
        public byte sector_count;
        public byte sector_count_exp;
    }

    struct cam_pinfo
    {
        public uint priority;
        public uint generation;
        public int index;
    }

    struct camq_entry
    {
        /// <summary>
        /// LIST_ENTRY(ccb_hdr)=le->*le_next
        /// </summary>
        public IntPtr le_next;
        /// <summary>
        /// LIST_ENTRY(ccb_hdr)=le->**le_prev
        /// </summary>
        public IntPtr le_prev;
        /// <summary>
        /// SLIST_ENTRY(ccb_hdr)=sle->*sle_next
        /// </summary>
        public IntPtr sle_next;
        /// <summary>
        /// TAILQ_ENTRY(ccb_hdr)=tqe->*tqe_next
        /// </summary>
        public IntPtr tqe_next;
        /// <summary>
        /// TAILQ_ENTRY(ccb_hdr)=tqe->**tqe_prev
        /// </summary>
        public IntPtr tqe_prev;
        /// <summary>
        /// STAILQ_ENTRY(ccb_hdr)=stqe->*stqe_next
        /// </summary>
        public IntPtr stqe_next;
    }

    struct timeval
    {
        public long tv_sec;
        /// <summary>long</summary>
        public IntPtr tv_usec;
    }

    struct ccb_qos_area
    {
        public timeval etime;
        public UIntPtr sim_data;
        public UIntPtr periph_data;
    }

    struct ccb_hdr
    {
        public cam_pinfo pinfo;
        public camq_entry xpt_links;
        public camq_entry sim_links;
        public camq_entry periph_links;
        public uint retry_count;
        public IntPtr cbfcnp;
        public xpt_opcode func_code;
        public uint status;
        public IntPtr path;
        public uint path_id;
        public uint target_id;
        public ulong target_lun;
        public uint flags;
        public uint xflags;
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 2)]
        public IntPtr[] periph_priv;
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 2)]
        public IntPtr[] sim_priv;
        public ccb_qos_area qos;
        public uint timeout;
        public timeval softtimeout;
    }

    struct scsi_sense_data
    {
        public byte error_code;
        [MarshalAs(UnmanagedType.ByValArray, SizeConst = 251)]
        public byte[] sense_buf;
    }

    /// <summary>
    /// SCSI I/O Request CCB used for the XPT_SCSI_IO and XPT_CONT_TARGET_IO function codes.
    /// </summary>
    struct cdb_scsiio
    {
        public ccb_hdr ccb_h;
        /// <summary>Ptr for next CCB for action</summary>    
        public IntPtr next_ccb;
        /// <summary>Ptr to mapping info</summary>
        public IntPtr req_map;
        /// <summary>Ptr to the data buf/SG list</summary>
        public IntPtr data_ptr;
        /// <summary>Data transfer length</summary>
        public uint dxfer_len;
        /// <summary>Autosense storage</summary>
        public scsi_sense_data sense_data;
        /// <summary>Number of bytes to autosense</summary>
        public byte sense_len;
        /// <summary>Number of bytes for the CDB</summary>
        public byte cdb_len;
        /// <summary>Number of SG list entries</summary>
        public short sglist_cnt;
        /// <summary>Returned SCSI status</summary>
        public byte scsi_status;
        /// <summary>Autosense resid length: 2's comp</summary>
        public sbyte sense_resid;
        /// <summary>Transfer residual length: 2's comp</summary>
        public int resid;
        /// <summary>Union for CDB bytes/pointer</summary>
        public IntPtr cdb_io;
        /// <summary>Pointer to the message buffer</summary>
        public IntPtr msg_ptr;
        /// <summary>Number of bytes for the Message</summary>
        public short msg_len;
        /// <summary>What to do for tag queueing. The tag action should be either the define below (to send a non-tagged transaction) or one of the defined scsi tag messages from scsi_message.h.</summary>
        public byte tag_action;
        /// <summary>tag id from initator (target mode)</summary>
        public uint tag_id;
        /// <summary>initiator id of who selected</summary>
        public uint init_id;
    }

    /// <summary>
    /// ATA I/O Request CCB used for the XPT_ATA_IO function code.
    /// </summary>
    struct ccb_ataio
    {
        public ccb_hdr ccb_h;
        /// <summary>Ptr for next CCB for action</summary>    
        public IntPtr next_ccb;
        /// <summary>ATA command register set</summary>
        public ata_cmd cmd;
        /// <summary>ATA result register set</summary>
        public ata_res res;
        /// <summary>Ptr to the data buf/SG list</summary>
        public IntPtr data_ptr;
        /// <summary>Data transfer length</summary>
        public uint dxfer_len;
        /// <summary>Transfer residual length: 2's comp</summary>
        public int resid;
        /// <summary>What to do for tag queueing. The tag action should be either the define below (to send a non-tagged transaction) or one of the defined scsi tag messages from scsi_message.h.</summary>
        public byte tag_action;
        /// <summary>tag id from initator (target mode)</summary>
        public uint tag_id;
        /// <summary>initiator id of who selected</summary>
        public uint init_id;
    }

    struct nvme_command
    {
        private ushort opc_fuse_rsvd1;
        /// <summary>
        /// command identifier
        /// </summary>
        public ushort cid;
        /// <summary>
        /// namespace identifier
        /// </summary>
        public uint nsid;
        /// <summary>
        /// reserved
        /// </summary>
        public uint rsvd2;
        /// <summary>
        /// reserved
        /// </summary>
        public uint rsvd3;
        /// <summary>
        /// metadata pointer
        /// </summary>
        public ulong mptr;
        /// <summary>
        /// prp entry 1
        /// </summary>
        public ulong prp1;
        /// <summary>
        /// prp entry 2
        /// </summary>
        public ulong prp2;
        /// <summary>
        /// command-specific
        /// </summary>
        public uint cdw10;
        /// <summary>
        /// command-specific
        /// </summary>
        public uint cdw11;
        /// <summary>
        /// command-specific
        /// </summary>
        public uint cdw12;
        /// <summary>
        /// command-specific
        /// </summary>
        public uint cdw13;
        /// <summary>
        /// command-specific
        /// </summary>
        public uint cdw14;
        /// <summary>
        /// command-specific
        /// </summary>
        public uint cdw15;

        /// <summary>
        /// opcode
        /// </summary>
        public byte opc => (byte)((opc_fuse_rsvd1 & 0xFF00) >> 8);
        /// <summary>
        /// fused operation
        /// </summary>
        public byte fuse => (byte)((opc_fuse_rsvd1 & 0xC0) >> 6);
        /// <summary>
        /// reserved
        /// </summary>
        public byte rsvd1 => (byte)(opc_fuse_rsvd1 & 0x3F);
    }

    struct nvme_status
    {
        private ushort status;

        /// <summary>
        /// phase tag
        /// </summary>
        public byte p => (byte)((status & 0x8000) >> 15);

        /// <summary>
        /// status code
        /// </summary>
        public byte sc => (byte)((status & 0x7F80) >> 7);

        /// <summary>
        /// status code type
        /// </summary>
        public byte sct => (byte)((status & 0x70) >> 4);

        /// <summary>
        /// reserved
        /// </summary>
        public byte rsvd2 => (byte)((status & 0xC) >> 15);

        /// <summary>
        /// more
        /// </summary>
        public byte m => (byte)((status & 0x2) >> 1);

        /// <summary>
        /// do not retry
        /// </summary>
        public byte dnr => (byte)(status & 0x1);
    }

    struct nvme_completion
    {
        /// <summary>
        /// command-specific
        /// </summary>
        public uint cdw0;

        /// <summary>
        /// reserved
        /// </summary>
        public uint rsvd1;

        /// <summary>
        /// submission queue head pointer
        /// </summary>
        public ushort sqhd;

        /// <summary>
        /// submission queue identifier
        /// </summary>
        public ushort sqid;

        /// <summary>
        /// command identifier
        /// </summary>
        public ushort cid;

        public nvme_status status;
    }

    /// <summary>
    /// NVMe I/O Request CCB used for the XPT_NVME_IO and XPT_NVME_ADMIN function codes.
    /// </summary>
    struct ccb_nvmeio
    {
        public ccb_hdr ccb_h;
        /// <summary>Ptr for next CCB for action</summary>    
        public IntPtr next_ccb;
        /// <summary>NVME command, per NVME standard</summary>
        public nvme_command cmd;
        /// <summary>NVME completion, per NVME standard</summary>
        public nvme_completion cpl;
        /// <summary>Ptr to the data buf/SG list</summary>
        public IntPtr data_ptr;
        /// <summary>Data transfer length</summary>
        public uint dxfer_len;
        /// <summary>Number of SG list entries</summary>
        public ushort sglist_cnt;
        /// <summary>padding for removed uint32_t</summary>
        public ushort unused;
    }
}