#include <stdio.h>
#include <stdlib.h>
#include <stdbool.h>
#include <stdint.h>
#include <stdarg.h>
#include <string.h>
#include <assert.h>
#include <dlfcn.h>

#include <dirent.h>

#include <sys/mman.h>
#include <sys/syscall.h>

#include <asm-generic/ioctl.h>

#include "xf86drm.h"

#define DRM_PVR_RESERVED1 (DRM_COMMAND_BASE + 0)
#define DRM_PVR_RESERVED2 (DRM_COMMAND_BASE + 1)
#define DRM_PVR_RESERVED3 (DRM_COMMAND_BASE + 2)
#define DRM_PVR_RESERVED4 (DRM_COMMAND_BASE + 3)
#define DRM_PVR_RESERVED5 (DRM_COMMAND_BASE + 4)
#define DRM_PVR_RESERVED6 (DRM_COMMAND_BASE + 5)

/* PVR includes */
#define SUPPORT_MEMINFO_IDS
#define SUPPORT_DRI_DRM_EXT
#include <config_kernel.h>
#include <sgxfeaturedefs.h>
#include <pvr_bridge.h>
#include <sgx_bridge.h>
#include <pvr_drm_shared.h>
#include <sgxconfig.h>
#include <sgx_mkif_km.h>
//#include <pvr_drm.h>

static int false_fd = 10241024;

#define PROLOG(func) \
    static typeof(func) *orig_##func = NULL; \
    if(!orig_##func) \
        orig_##func = dlsym(RTLD_NEXT, #func);

int open(const char *pathname, int flags, mode_t mode) {
    printf("Called open on %s (%d)\n", pathname, flags);
    PROLOG(open);
    return orig_open(pathname, flags, mode);
}

int open64(const char *pathname, int flags, ...) {
    printf("Called open64 on %s (%d)\n", pathname, flags);
    PROLOG(open64);
    int fd = orig_open64(pathname, flags);
    if (strcmp(pathname, "/dev/dri/renderD128") == 0) {
        printf("Spoofing FD!\n");
        return false_fd;
    }
    return fd;
}

#define DEV_NAME "pvr"
#define DEV_DATE "20110701"
#define DEV_DESC "Imagination Technologies PVR DRM"

static bool spoof_ioctl(int fd, int request, void *ptr) {
    int ioctl_nr = _IOC_NR(request);
    switch(ioctl_nr) {
        case _IOC_NR(DRM_IOCTL_VERSION): {
            printf("Spoofing device info\n");
            drmVersionPtr version = (drmVersionPtr)ptr;
            version->version_major = 1;
            version->version_minor = 13;
            version->version_patchlevel = 3341330;
            version->name_len = sizeof(DEV_NAME);
            version->date_len = sizeof(DEV_DATE);
            version->desc_len = sizeof(DEV_DESC);

            if (version->name)
                strcpy(version->name, DEV_NAME);
            if (version->date)
                strcpy(version->date, DEV_DATE);
            if (version->desc)
                strcpy(version->desc, DEV_DESC);

            break;
        }

#if 0
        case _IOC_NR(DRM_IOCTL_GET_MAGIC):
            printf(">>> ioctl(DRM_IOCTL_GET_MAGIC)\n");
            break;
        case _IOC_NR(DRM_IOCTL_GET_UNIQUE):
            printf(">>> ioctl(DRM_IOCTL_GET_UNIQUE)\n");
            break;
        case _IOC_NR(DRM_IOCTL_SET_VERSION):
            printf(">>> ioctl(DRM_IOCTL_SET_VERSION)\n");
            {
                struct drm_set_version *data = ptr;
                printf("\t%d %d %d %d\n", data->drm_di_major,
                                        data->drm_di_minor,
                                        data->drm_dd_major,
                                        data->drm_dd_minor);
            }
            break;
#endif
        case _IOC_NR(DRM_IOCTL_DROP_MASTER):
            printf(">>> ioctl(DRM_IOCTL_DROP_MASTER)\n");
            return 0;
        case PVR_DRM_SRVKM_CMD:
            printf("srv command 0x%x\n", PVR_DRM_SRVKM_CMD);
            //fwrite(ptr, 1, sizeof(PVRSRV_BRIDGE_PACKAGE), log_file);
            //PPRINT(stdout, ptr, PVRSRV_BRIDGE_PACKAGE);
            //return pvrsrv_ioctl(fd, ptr);
            break;
        case PVR_DRM_IS_MASTER_CMD:
            printf(">>> ioctl(PVR_DRM_IS_MASTER_CMD) 0x%x\n", PVR_DRM_SRVKM_CMD);
            /* From KMD source code this seems to always return 0 */
            break;
        default:
            printf("Unimplemented ioctl 0x%x\n", ioctl_nr);
            assert(false);
            break;
    }
    return 0;
}

int ioctl(int fd, int request, ...) {
    PROLOG(ioctl);
    int ioc_size = _IOC_SIZE(request);
    bool pvr = fd == false_fd;

    //printf("Size is %d\n", ioc_size);
    void *ptr = NULL;
    if(ioc_size) {
        va_list args;
        va_start(args, request);
        ptr = va_arg(args, void *);
        va_end(args);
    }

    printf("Got ioctl %d!\n", fd);

    if (pvr)
        return spoof_ioctl(fd, request, ptr);
    else
        return orig_ioctl(fd, request, ptr);
}

int openat(int dirfd, const char *pathname, int flags, ...) {
    printf("Called openat on %s (%d) (%d)\n", pathname, dirfd, flags);
    PROLOG(openat);

    return orig_openat(dirfd, pathname, flags);
}

int openat64(int fd, const char * path, int oflag, ...) {
    printf("Called openat64 %s\n", path);
    PROLOG(openat64);
    return orig_openat64(fd, path, oflag);
}

DIR *opendir(const char *dirname) {
    printf("Opening dir %s\n", dirname);
    PROLOG(opendir);
    return orig_opendir(dirname);
}

struct dirent *readdir(DIR *dirp) {
    PROLOG(readdir);
    struct dirent *out = orig_readdir(dirp);
    if (out) {
        //printf("Reading %d %d %s\n", (int)out->d_type, (int)out->d_reclen, (char*)out->d_name);
    }
    return out;
}