// Licensed to the Apache Software Foundation (ASF) under one
// or more contributor license agreements.  See the NOTICE file
// distributed with this work for additional information
// regarding copyright ownership.  The ASF licenses this file
// to you under the Apache License, Version 2.0 (the
// "License"); you may not use this file except in compliance
// with the License.  You may obtain a copy of the License at
//
//   http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing,
// software distributed under the License is distributed on an
// "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
// KIND, either express or implied.  See the License for the
// specific language governing permissions and limitations
// under the License..

#include <stdio.h>
#include <string.h>
#include <assert.h>

#include <unistd.h>
#include <pwd.h>
#define MAX_PATH FILENAME_MAX

#include "sgx_urts.h"
#include "app.h"
#include "Enclave_u.h"


sgx_enclave_id_t global_eid = 0;

typedef struct _sgx_errlist_t {
    sgx_status_t err;
    const char *msg;
    const char *sug; /* Suggestion */
} sgx_errlist_t;

/* Error code returned by sgx_create_enclave */
static sgx_errlist_t sgx_errlist[] = {
    {
        SGX_ERROR_UNEXPECTED,
        "Unexpected error occurred.",
        NULL
    },
    {
        SGX_ERROR_INVALID_PARAMETER,
        "Invalid parameter.",
        NULL
    },
    {
        SGX_ERROR_OUT_OF_MEMORY,
        "Out of memory.",
        NULL
    },
    {
        SGX_ERROR_ENCLAVE_LOST,
        "Power transition occurred.",
        "Please refer to the sample \"PowerTransition\" for details."
    },
    {
        SGX_ERROR_INVALID_ENCLAVE,
        "Invalid enclave image.",
        NULL
    },
    {
        SGX_ERROR_INVALID_ENCLAVE_ID,
        "Invalid enclave identification.",
        NULL
    },
    {
        SGX_ERROR_INVALID_SIGNATURE,
        "Invalid enclave signature.",
        NULL
    },
    {
        SGX_ERROR_OUT_OF_EPC,
        "Out of EPC memory.",
        NULL
    },
    {
        SGX_ERROR_NO_DEVICE,
        "Invalid SGX device.",
        "Please make sure SGX module is enabled in the BIOS, and install SGX driver afterwards."
    },
    {
        SGX_ERROR_MEMORY_MAP_CONFLICT,
        "Memory map conflicted.",
        NULL
    },
    {
        SGX_ERROR_INVALID_METADATA,
        "Invalid enclave metadata.",
        NULL
    },
    {
        SGX_ERROR_DEVICE_BUSY,
        "SGX device was busy.",
        NULL
    },
    {
        SGX_ERROR_INVALID_VERSION,
        "Enclave version was invalid.",
        NULL
    },
    {
        SGX_ERROR_INVALID_ATTRIBUTE,
        "Enclave was not authorized.",
        NULL
    },
    {
        SGX_ERROR_ENCLAVE_FILE_ACCESS,
        "Can't open enclave file.",
        NULL
    },
};

/* Check error conditions for loading enclave */
void print_error_message(sgx_status_t ret)
{
    size_t idx = 0;
    size_t ttl = sizeof sgx_errlist/sizeof sgx_errlist[0];

    for (idx = 0; idx < ttl; idx++) {
        if(ret == sgx_errlist[idx].err) {
            if(NULL != sgx_errlist[idx].sug)
                printf("Info: %s\n", sgx_errlist[idx].sug);
            printf("Error: %s\n", sgx_errlist[idx].msg);
            break;
        }
    }

    if (idx == ttl)
        printf("Error: Unexpected error occurred.\n");
}

int initialize_enclave(void)
{
    sgx_launch_token_t token = {0};
    sgx_status_t ret = SGX_ERROR_UNEXPECTED;
    int updated = 0;

    /* call sgx_create_enclave to initialize an enclave instance */
    /* Debug Support: set 2nd parameter to 1 */
    ret = sgx_create_enclave(ENCLAVE_FILENAME, SGX_DEBUG_FLAG, &token, &updated, &global_eid, NULL);
    if (ret != SGX_SUCCESS) {
        print_error_message(ret);
        return -1;
    }
    printf("[+] global_eid: %ld\n", global_eid);
    return 0;
}

/* Application entry */
int SGX_CDECL main(int argc, char *argv[])
{
    sgx_status_t sgx_ret = SGX_SUCCESS;
    sgx_status_t enclave_ret = SGX_SUCCESS;

    (void)(argc);
    (void)(argv);

    /* Initialize the enclave */
    if(initialize_enclave() < 0){
        printf("Enter a character before exit ...\n");
        getchar();
        return -1;
    }

    const char* str = "This is normal world string passed into enclave!\n";
    size_t len = strlen(str);

    sgx_ret = say_something(global_eid,
                            &enclave_ret,
                            (const uint8_t *) str,
                            len);

    if(sgx_ret != SGX_SUCCESS) {
        print_error_message(sgx_ret);
        return -1;
    }

    if(enclave_ret != SGX_SUCCESS) {
        print_error_message(enclave_ret);
        return -1;
    }

    printf("[+] say_something success ...\n");

    /* Destroy the enclave */
    sgx_destroy_enclave(global_eid);

    return 0;
}