#include <3ds.h>
#include <string.h>
#include "fsreg.h"
#include "srvsys.h"

static Handle fsregHandle;
static int fsregRefCount;

Result
fsregInit(void)
{
    Result ret = 0;

    if (AtomicPostIncrement(&fsregRefCount))
        return 0;

    ret = srvSysGetServiceHandle(&fsregHandle, "fs:REG");

    if (R_FAILED(ret))
        AtomicDecrement(&fsregRefCount);
    return ret;
}

void
fsregExit(void)
{
    if (AtomicDecrement(&fsregRefCount))
        return;
    svcCloseHandle(fsregHandle);
}

Result
FSREG_CheckHostLoadId(u64 prog_handle)
{
    u32 *cmdbuf = getThreadCommandBuffer();

    cmdbuf[0] = IPC_MakeHeader(0x406, 2, 0); // 0x4060080
    cmdbuf[1] = (u32)(prog_handle);
    cmdbuf[2] = (u32)(prog_handle >> 32);

    Result ret = 0;
    if (R_FAILED(ret = svcSendSyncRequest(fsregHandle)))
        return ret;

    return cmdbuf[1];
}

Result
FSREG_LoadProgram(u64 *prog_handle, FS_ProgramInfo *title)
{
    u32 *cmdbuf = getThreadCommandBuffer();

    cmdbuf[0] = IPC_MakeHeader(0x404, 4, 0); // 0x4040100
    memcpy(&cmdbuf[1], &title->programId, sizeof(u64));
    *(u8 *)&cmdbuf[3] = title->mediaType;
    memcpy(((u8 *)&cmdbuf[3]) + 1, &title->padding, 7);

    Result ret = 0;
    if (R_FAILED(ret = svcSendSyncRequest(fsregHandle)))
        return ret;
    *prog_handle = *(u64 *)&cmdbuf[2];

    return cmdbuf[1];
}

Result
FSREG_GetProgramInfo(exheader_header *exheader, u32 entry_count, u64 prog_handle)
{
    u32 *cmdbuf = getThreadCommandBuffer();

    cmdbuf[0] = IPC_MakeHeader(0x403, 3, 0); // 0x40300C0
    cmdbuf[1] = entry_count;
    *(u64 *)&cmdbuf[2] = prog_handle;
    cmdbuf[64] = ((entry_count << 10) << 14) | 2;
    cmdbuf[65] = (u32)exheader;

    Result ret = 0;
    if (R_FAILED(ret = svcSendSyncRequest(fsregHandle)))
        return ret;

    return cmdbuf[1];
}

Result
FSREG_UnloadProgram(u64 prog_handle)
{
    u32 *cmdbuf = getThreadCommandBuffer();

    cmdbuf[0] = IPC_MakeHeader(0x405, 2, 0); // 0x4050080
    cmdbuf[1] = (u32)(prog_handle);
    cmdbuf[2] = (u32)(prog_handle >> 32);

    Result ret = 0;
    if (R_FAILED(ret = svcSendSyncRequest(fsregHandle)))
        return ret;

    return cmdbuf[1];
}

Result
FSREG_Unregister(u32 pid)
{
    u32 *cmdbuf = getThreadCommandBuffer();

    cmdbuf[0] = IPC_MakeHeader(0x402, 1, 0); // 0x4020040
    cmdbuf[1] = pid;

    Result ret = 0;
    if (R_FAILED(ret = svcSendSyncRequest(fsregHandle)))
        return ret;

    return cmdbuf[1];
}

Result
FSREG_Register(u32 pid, u64 prog_handle, FS_ProgramInfo *info, void *storageinfo)
{
    u32 *cmdbuf = getThreadCommandBuffer();

    cmdbuf[0] = IPC_MakeHeader(0x401, 0xf, 0); // 0x40103C0
    cmdbuf[1] = pid;
    *(u64 *)&cmdbuf[2] = prog_handle;
    memcpy(&cmdbuf[4], &info->programId, sizeof(u64));
    *(u8 *)&cmdbuf[6] = info->mediaType;
    memcpy(((u8 *)&cmdbuf[6]) + 1, &info->padding, 7);
    memcpy((u8 *)&cmdbuf[8], storageinfo, 32);

    Result ret = 0;
    if (R_FAILED(ret = svcSendSyncRequest(fsregHandle)))
        return ret;

    return cmdbuf[1];
}