/**
 *  @file simple_use_case_configfile_c.c
 *
 *  @brief Sample code to demonstrate the Quantum Origin SDK C API. A config file is used for configuration.

 *  System: Quantum Origin SDK
 *  Component: Quantum Origin SDK Documentation
 *
 *  Please contact Quantinuum for production license(s).
 *
 *  @author Quantinuum CSE
 */

// clang-format off

#include <stdlib.h>
#include <stddef.h>
#include <stdio.h>
#include <string.h>
#include <stdbool.h>
#include <stdint.h>
#include <ctype.h>

#include <quantum_origin/quantum_origin_sdk_c.h>

#define BUFFER_SIZE 400U

// Forward declaration to ensure that the interface function is correctly defined.
static tQOSDK_LOGGER_CALLBACK_FN my_qo_logger_callback;


//--------------------------------------------------------------
// Logger callback
//--------------------------------------------------------------
static void my_qo_logger_callback(const tQOSDK_LOGLEVEL logLevel, const char *szMsg, size_t msgLen)
{
    // Store or present the inbound message somewhere.
    switch(logLevel)
    {
        case QOSDK_LOGLEVEL_NONE     : break;
        case QOSDK_LOGLEVEL_CRITICAL : fprintf(stderr, "[QuantumOrigin] CRITICAL: %.*s\n", (int)msgLen, szMsg); break;
        case QOSDK_LOGLEVEL_ERROR    : fprintf(stderr, "[QuantumOrigin] ERROR: %.*s\n", (int)msgLen, szMsg); break;
        case QOSDK_LOGLEVEL_WARNING  : fprintf(stderr, "[QuantumOrigin] WARNING: %.*s\n", (int)msgLen, szMsg); break;
        case QOSDK_LOGLEVEL_INFO     : fprintf(stderr, "[QuantumOrigin] INFO: %.*s\n", (int)msgLen, szMsg); break;
        case QOSDK_LOGLEVEL_DEBUG    : fprintf(stderr, "[QuantumOrigin] DEBUG: %.*s\n", (int)msgLen, szMsg); break;
        default:
        case QOSDK_LOGLEVEL_TRACE    : fprintf(stderr, "[QuantumOrigin] TRACE: %.*s\n", (int)msgLen, szMsg); break;
    }
}

//--------------------------------------------------------------
// Simple hex dump
//--------------------------------------------------------------
static void hex_dump(const char *szTitle, const uint8_t *pData, size_t cbData)
{
    printf("%s [%lu bytes]: ", szTitle ? szTitle : "HEXDUMP: ", (unsigned long)cbData);
    if (pData && cbData)
    {
        for (int ii = 0; ii < cbData; ii++)
        {
            printf("%2.2X ", pData[ii]);
        }
    }
    printf("\n");
}

//--------------------------------------------------------------
// Main
//--------------------------------------------------------------
int main(int argc, char **argv)
{
    tQOSDK_CTX *   pQuantumOrigin       = NULL;
    uint32_t       bytesRequested       = 0xFFFFFFFF;
    size_t         bytesSupplied        = 0;
    unsigned char  resultBuffer[BUFFER_SIZE];
    int            erc                  = ERC_QOSDK_UNSPECIFIED_ERROR;
    char *         szConfigFilename     = "config-sample-01.yml";

    // Parse parameters
    for (int jj = 1; jj < argc; jj++)
    {
        if (strcmp(argv[jj], "--help") == 0)
        {
            printf("USAGE: simple_use_case_configfile_c [<BytesOfRandomness>] // (Default = 32 bytes)\n");
            return EXIT_SUCCESS;
        }
        if (bytesRequested == 0xFFFFFFFF)
        {
            if (argv[jj][0] == '-')
            {
                fprintf(stderr, "ERROR: Number of bytes requested cannot be negative\n");
                return EXIT_FAILURE;
            }
            bytesRequested = (uint32_t)atol(argv[jj]);
            if (bytesRequested > BUFFER_SIZE)
            {
                fprintf(stderr, "ERROR: Number of bytes requested must be <= %u\n", BUFFER_SIZE);
                return EXIT_FAILURE;
            }
            continue;
        }
    }

    if (bytesRequested == 0xFFFFFFFF)
    {
        bytesRequested = 32;
    }

    // Initialise Quantum Origin Logging
    erc = qosdk_initialise_logging(QOSDK_LOGMODE_STDERR, QOSDK_LOGLEVEL_WARNING, NULL);
    if (erc)
    {
        const char *szQuantumOriginError = qosdk_get_error_description();
        fprintf(stderr, "ERROR: Failed to initialize logging (QuantumOriginError=%d: \"%s\")\n", erc, szQuantumOriginError?szQuantumOriginError:"Unspecified");
        return EXIT_FAILURE;
    }
    // Register a Quantum Origin Logging callback
    erc = qosdk_set_logging_callback(my_qo_logger_callback);
    if (erc)
    {
        const char *szQuantumOriginError = qosdk_get_error_description();
        fprintf(stderr, "ERROR: Failed to set logging callback (QuantumOriginError=%d: \"%s\")\n", erc, szQuantumOriginError?szQuantumOriginError:"Unspecified");
        return EXIT_FAILURE;
    }

    // Initialise Quantum Origin
    pQuantumOrigin = qosdk_init_from_config_file(szConfigFilename, "");
    if (pQuantumOrigin == NULL)
    {
        erc = qosdk_get_error_code();
        const char *szQuantumOriginError = qosdk_get_error_description();
        fprintf(stderr, "ERROR: Failed to initialize Quantum Origin with qosdk_init_from_config_file(\"%s\") (QuantumOriginError=%d: \"%s\")\n", szConfigFilename, erc, szQuantumOriginError?szQuantumOriginError:"Unspecified");
        // Cleanup and exit
        qosdk_clear_logging_callback();
        return EXIT_FAILURE;
    }


    // Exercise the logging callback
    qosdk_log_message(QOSDK_LOGLEVEL_WARNING, "This is a test warning message");

    // Get randomness
    bytesSupplied = 0;
    erc = qosdk_get_randomness(pQuantumOrigin, resultBuffer, bytesRequested, &bytesSupplied);
    if (erc)
    {
        const char *szQuantumOriginError = qosdk_get_error_description();
        fprintf(stderr, "ERROR: Failed to get randomness. (QuantumOriginError=%d: \"%s\")\n", erc, szQuantumOriginError?szQuantumOriginError:"Unspecified");
        // Cleanup and exit
        qosdk_destroy(pQuantumOrigin);
        qosdk_clear_logging_callback();
        return EXIT_FAILURE;
    }

    // Print results
    hex_dump("RESULT", resultBuffer, bytesSupplied);

    // Cleanup and exit
    qosdk_destroy(pQuantumOrigin);
    qosdk_clear_logging_callback();

    return EXIT_SUCCESS;
}