/***************************************************************************
 * Copyright (C) 2016
 * by Dimok
 *
 * This software is provided 'as-is', without any express or implied
 * warranty. In no event will the authors be held liable for any
 * damages arising from the use of this software.
 *
 * Permission is granted to anyone to use this software for any
 * purpose, including commercial applications, and to alter it and
 * redistribute it freely, subject to the following restrictions:
 *
 * 1. The origin of this software must not be misrepresented; you
 * must not claim that you wrote the original software. If you use
 * this software in a product, an acknowledgment in the product
 * documentation would be appreciated but is not required.
 *
 * 2. Altered source versions must be plainly marked as such, and
 * must not be misrepresented as being the original software.
 *
 * 3. This notice may not be removed or altered from any source
 * distribution.
 ***************************************************************************/
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include "imports.h"
#include "fsa.h"
#include "svc.h"
#include "text.h"
#include "logger.h"
#include "fsa.h"

#define IOS_ERROR_UNKNOWN_VALUE     0xFFFFFFD6
#define IOS_ERROR_INVALID_ARG       0xFFFFFFE3
#define IOS_ERROR_INVALID_SIZE      0xFFFFFFE9
#define IOS_ERROR_UNKNOWN           0xFFFFFFF7
#define IOS_ERROR_NOEXISTS          0xFFFFFFFA

#define IOCTL_MEM_WRITE             0x00
#define IOCTL_MEM_READ              0x01
#define IOCTL_SVC                   0x02
#define IOCTL_MEMCPY                0x04
#define IOCTL_REPEATED_WRITE        0x05
#define IOCTL_KERN_READ32           0x06
#define IOCTL_KERN_WRITE32          0x07

#define IOCTL_FSA_OPEN              0x40
#define IOCTL_FSA_CLOSE             0x41
#define IOCTL_FSA_MOUNT             0x42
#define IOCTL_FSA_UNMOUNT           0x43
#define IOCTL_FSA_GETDEVICEINFO     0x44
#define IOCTL_FSA_OPENDIR           0x45
#define IOCTL_FSA_READDIR           0x46
#define IOCTL_FSA_CLOSEDIR          0x47
#define IOCTL_FSA_MAKEDIR           0x48
#define IOCTL_FSA_OPENFILE          0x49
#define IOCTL_FSA_READFILE          0x4A
#define IOCTL_FSA_WRITEFILE         0x4B
#define IOCTL_FSA_STATFILE          0x4C
#define IOCTL_FSA_CLOSEFILE         0x4D
#define IOCTL_FSA_SETFILEPOS        0x4E
#define IOCTL_FSA_GETSTAT           0x4F
#define IOCTL_FSA_REMOVE            0x50
#define IOCTL_FSA_REWINDDIR         0x51
#define IOCTL_FSA_CHDIR             0x52
#define IOCTL_FSA_RENAME            0x53
#define IOCTL_FSA_RAW_OPEN          0x54
#define IOCTL_FSA_RAW_READ          0x55
#define IOCTL_FSA_RAW_WRITE         0x56
#define IOCTL_FSA_RAW_CLOSE         0x57
#define IOCTL_FSA_CHANGEMODE        0x58

static u8 threadStack[0x1000] __attribute__((aligned(0x20)));

static int ipc_ioctl(ipcmessage *message)
{
    int res = 0;

    switch(message->ioctl.command)
    {
    case IOCTL_MEM_WRITE:
    {
        if(message->ioctl.length_in < 4)
        {
            res = IOS_ERROR_INVALID_SIZE;
        }
        else
        {
            memcpy((void*)message->ioctl.buffer_in[0], message->ioctl.buffer_in + 1, message->ioctl.length_in - 4);
        }
        break;
    }
    case IOCTL_MEM_READ:
    {
        if(message->ioctl.length_in < 4)
        {
            res = IOS_ERROR_INVALID_SIZE;
        }
        else
        {
            memcpy(message->ioctl.buffer_io, (void*)message->ioctl.buffer_in[0], message->ioctl.length_io);
        }
        break;
    }
    case IOCTL_SVC:
    {
        if((message->ioctl.length_in < 4) || (message->ioctl.length_io < 4))
        {
            res = IOS_ERROR_INVALID_SIZE;
        }
        else
        {
            int svc_id = message->ioctl.buffer_in[0];
            int size_arguments = message->ioctl.length_in - 4;

            u32 arguments[8];
            memset(arguments, 0x00, sizeof(arguments));
            memcpy(arguments, message->ioctl.buffer_in + 1, (size_arguments < 8 * 4) ? size_arguments : (8 * 4));

            // return error code as data
            message->ioctl.buffer_io[0] = ((int (*const)(u32, u32, u32, u32, u32, u32, u32, u32))(MCP_SVC_BASE + svc_id * 8))(arguments[0], arguments[1], arguments[2], arguments[3], arguments[4], arguments[5], arguments[6], arguments[7]);
        }
        break;
    }
    case IOCTL_MEMCPY:
    {
        if(message->ioctl.length_in < 12)
        {
            res = IOS_ERROR_INVALID_SIZE;
        }
        else
        {
            memcpy((void*)message->ioctl.buffer_in[0], (void*)message->ioctl.buffer_in[1], message->ioctl.buffer_in[2]);
        }
        break;
    }
    case IOCTL_REPEATED_WRITE:
    {
        if(message->ioctl.length_in < 12)
        {
            res = IOS_ERROR_INVALID_SIZE;
        }
        else
        {
            u32* dst = (u32*)message->ioctl.buffer_in[0];
            u32* cache_range = (u32*)(message->ioctl.buffer_in[0] & ~0xFF);
            u32 value = message->ioctl.buffer_in[1];
            u32 n = message->ioctl.buffer_in[2];

            u32 old = *dst;
            int i;
            for(i = 0; i < n; i++)
            {
                if(*dst != old)
                {
                    if(*dst == 0x0) old = *dst;
                    else
                    {
                        *dst = value;
                        svcFlushDCache(cache_range, 0x100);
                        break;
                    }
                }else
                {
                    svcInvalidateDCache(cache_range, 0x100);
                    usleep(50);
                }
            }
        }
        break;
    }
    case IOCTL_KERN_READ32:
    {
        if((message->ioctl.length_in < 4) || (message->ioctl.length_io < 4))
        {
            res = IOS_ERROR_INVALID_SIZE;
        }
        else
        {
            for(u32 i = 0; i < (message->ioctl.length_io/4); i++)
            {
                message->ioctl.buffer_io[i] = svcRead32(message->ioctl.buffer_in[0] + i * 4);
            }
        }
        break;
    }
    case IOCTL_KERN_WRITE32:
    {
        //! TODO: add syscall as on kern_read32
        res = IOS_ERROR_NOEXISTS;
        break;
    }
    //!--------------------------------------------------------------------------------------------------------------
    //! FSA handles for better performance
    //!--------------------------------------------------------------------------------------------------------------
    //! TODO: add checks for i/o buffer length
    case IOCTL_FSA_OPEN:
    {
        message->ioctl.buffer_io[0] = svcOpen("/dev/fsa", 0);
        break;
    }
    case IOCTL_FSA_CLOSE:
    {
        int fd = message->ioctl.buffer_in[0];
        message->ioctl.buffer_io[0] = svcClose(fd);
        break;
    }
    case IOCTL_FSA_MOUNT:
    {
        int fd = message->ioctl.buffer_in[0];
        char *device_path = ((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[1];
        char *volume_path = ((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[2];
        u32 flags = message->ioctl.buffer_in[3];
        char *arg_string = (message->ioctl.buffer_in[4] > 0) ? (((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[4]) : 0;
        int arg_string_len = message->ioctl.buffer_in[5];

        message->ioctl.buffer_io[0] = FSA_Mount(fd, device_path, volume_path, flags, arg_string, arg_string_len);
        break;
    }
    case IOCTL_FSA_UNMOUNT:
    {
        int fd = message->ioctl.buffer_in[0];
        char *device_path = ((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[1];
        u32 flags = message->ioctl.buffer_in[2];

        message->ioctl.buffer_io[0] = FSA_Unmount(fd, device_path, flags);
        break;
    }
    case IOCTL_FSA_GETDEVICEINFO:
    {
        int fd = message->ioctl.buffer_in[0];
        char *device_path = ((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[1];
        int type = message->ioctl.buffer_in[2];

        message->ioctl.buffer_io[0] = FSA_GetDeviceInfo(fd, device_path, type, message->ioctl.buffer_io + 1);
        break;
    }
    case IOCTL_FSA_OPENDIR:
    {
        int fd = message->ioctl.buffer_in[0];
        char *path = ((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[1];

        message->ioctl.buffer_io[0] = FSA_OpenDir(fd, path, (int*)message->ioctl.buffer_io + 1);
        break;
    }
    case IOCTL_FSA_READDIR:
    {
        int fd = message->ioctl.buffer_in[0];
        int handle = message->ioctl.buffer_in[1];

        message->ioctl.buffer_io[0] = FSA_ReadDir(fd, handle, (directoryEntry_s*)(message->ioctl.buffer_io + 1));
        break;
    }
    case IOCTL_FSA_CLOSEDIR:
    {
        int fd = message->ioctl.buffer_in[0];
        int handle = message->ioctl.buffer_in[1];

        message->ioctl.buffer_io[0] = FSA_CloseDir(fd, handle);
        break;
    }
    case IOCTL_FSA_MAKEDIR:
    {
        int fd = message->ioctl.buffer_in[0];
        char *path = ((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[1];
        u32 flags = message->ioctl.buffer_in[2];

        message->ioctl.buffer_io[0] = FSA_MakeDir(fd, path, flags);
        break;
    }
    case IOCTL_FSA_OPENFILE:
    {
        int fd = message->ioctl.buffer_in[0];
        char *path = ((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[1];
        char *mode = ((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[2];

        message->ioctl.buffer_io[0] = FSA_OpenFile(fd, path, mode, (int*)message->ioctl.buffer_io + 1);
        break;
    }
    case IOCTL_FSA_READFILE:
    {
        int fd = message->ioctl.buffer_in[0];
        u32 size = message->ioctl.buffer_in[1];
        u32 cnt = message->ioctl.buffer_in[2];
        int fileHandle = message->ioctl.buffer_in[3];
        u32 flags = message->ioctl.buffer_in[4];

        message->ioctl.buffer_io[0] = FSA_ReadFile(fd, ((u8*)message->ioctl.buffer_io) + 0x40, size, cnt, fileHandle, flags);
        break;
    }
    case IOCTL_FSA_WRITEFILE:
    {
        int fd = message->ioctl.buffer_in[0];
        u32 size = message->ioctl.buffer_in[1];
        u32 cnt = message->ioctl.buffer_in[2];
        int fileHandle = message->ioctl.buffer_in[3];
        u32 flags = message->ioctl.buffer_in[4];

        message->ioctl.buffer_io[0] = FSA_WriteFile(fd, ((u8*)message->ioctl.buffer_in) + 0x40, size, cnt, fileHandle, flags);
        break;
    }
    case IOCTL_FSA_STATFILE:
    {
        int fd = message->ioctl.buffer_in[0];
        int fileHandle = message->ioctl.buffer_in[1];

        message->ioctl.buffer_io[0] = FSA_StatFile(fd, fileHandle, (fileStat_s*)(message->ioctl.buffer_io + 1));
        break;
    }
    case IOCTL_FSA_CLOSEFILE:
    {
        int fd = message->ioctl.buffer_in[0];
        int fileHandle = message->ioctl.buffer_in[1];

        message->ioctl.buffer_io[0] = FSA_CloseFile(fd, fileHandle);
        break;
    }
    case IOCTL_FSA_SETFILEPOS:
    {
        int fd = message->ioctl.buffer_in[0];
        int fileHandle = message->ioctl.buffer_in[1];
        u32 position = message->ioctl.buffer_in[2];

        message->ioctl.buffer_io[0] = FSA_SetPosFile(fd, fileHandle, position);
        break;
    }
    case IOCTL_FSA_GETSTAT:
    {
        int fd = message->ioctl.buffer_in[0];
        char *path = ((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[1];

        message->ioctl.buffer_io[0] = FSA_GetStat(fd, path, (fileStat_s*)(message->ioctl.buffer_io + 1));
        break;
    }
    case IOCTL_FSA_REMOVE:
    {
        int fd = message->ioctl.buffer_in[0];
        char *path = ((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[1];

        message->ioctl.buffer_io[0] = FSA_Remove(fd, path);
        break;
    }
    case IOCTL_FSA_REWINDDIR:
    {
        int fd = message->ioctl.buffer_in[0];
        int dirFd = message->ioctl.buffer_in[1];

        message->ioctl.buffer_io[0] = FSA_RewindDir(fd, dirFd);
        break;
    }
    case IOCTL_FSA_CHDIR:
    {
        int fd = message->ioctl.buffer_in[0];
        char *path = ((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[1];

        message->ioctl.buffer_io[0] = FSA_ChangeDir(fd, path);
        break;
    }
    case IOCTL_FSA_RAW_OPEN:
    {
        int fd = message->ioctl.buffer_in[0];
        char *path = ((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[1];

        message->ioctl.buffer_io[0] = FSA_RawOpen(fd, path, (int*)(message->ioctl.buffer_io + 1));
        break;
    }
    case IOCTL_FSA_RAW_READ:
    {
        int fd = message->ioctl.buffer_in[0];
        u32 block_size = message->ioctl.buffer_in[1];
        u32 cnt = message->ioctl.buffer_in[2];
        u64 sector_offset = ((u64)message->ioctl.buffer_in[3] << 32ULL) | message->ioctl.buffer_in[4];
        int deviceHandle = message->ioctl.buffer_in[5];

        message->ioctl.buffer_io[0] = FSA_RawRead(fd, ((u8*)message->ioctl.buffer_io) + 0x40, block_size, cnt, sector_offset, deviceHandle);
        break;
    }
    case IOCTL_FSA_RAW_WRITE:
    {
        int fd = message->ioctl.buffer_in[0];
        u32 block_size = message->ioctl.buffer_in[1];
        u32 cnt = message->ioctl.buffer_in[2];
        u64 sector_offset = ((u64)message->ioctl.buffer_in[3] << 32ULL) | message->ioctl.buffer_in[4];
        int deviceHandle = message->ioctl.buffer_in[5];

        message->ioctl.buffer_io[0] = FSA_RawWrite(fd, ((u8*)message->ioctl.buffer_in) + 0x40, block_size, cnt, sector_offset, deviceHandle);
        break;
    }
    case IOCTL_FSA_RAW_CLOSE:
    {
        int fd = message->ioctl.buffer_in[0];
        int deviceHandle = message->ioctl.buffer_in[1];

        message->ioctl.buffer_io[0] = FSA_RawClose(fd, deviceHandle);
        break;
    }
    case IOCTL_FSA_CHANGEMODE:
    {
        int fd = message->ioctl.buffer_in[0];
        char *path = ((char *)message->ioctl.buffer_in) + message->ioctl.buffer_in[1];
        int mode = message->ioctl.buffer_in[2];

        message->ioctl.buffer_io[0] = FSA_ChangeMode(fd, path, mode);
        break;
    }
    default:
        res = IOS_ERROR_INVALID_ARG;
        break;
    }

    return res;
}

static int ipc_thread(void *arg)
{
    int res;
    ipcmessage *message;
    u32 messageQueue[0x10];

    int queueId = svcCreateMessageQueue(messageQueue, sizeof(messageQueue) / 4);

    if(svcRegisterResourceManager("/dev/iosuhax", queueId) != 0)
    {
        return 0;
    }

	while(1)
	{
        res = svcReceiveMessage(queueId, &message, 0);
        if(res < 0)
        {
            usleep(10000);
            continue;
        }

        switch(message->command)
        {
            case IOS_OPEN:
            {
                log_printf("IOS_OPEN\n");
                res = 0;
                break;
            }
            case IOS_CLOSE:
            {
                log_printf("IOS_CLOSE\n");
                res = 0;
                break;
            }
            case IOS_IOCTL:
            {
                log_printf("IOS_IOCTL\n");
                res = ipc_ioctl(message);
                break;
            }
            case IOS_IOCTLV:
            {
                log_printf("IOS_IOCTLV\n");
                res = 0;
                break;
            }
            default:
            {
                log_printf("unexpected command 0x%X\n", message->command);
                res = IOS_ERROR_UNKNOWN_VALUE;
                break;
            }
        }

        svcResourceReply(message, res);
	}
}

void ipc_init(void)
{
    int threadId = svcCreateThread(ipc_thread, 0, (u32*)(threadStack + sizeof(threadStack)), sizeof(threadStack), 0x78, 1);
    if(threadId >= 0)
        svcStartThread(threadId);
}