#include <iostream>
#include <cxxopts.hpp>

#include <filesystem>
#include <fstream>

#include <stdexcept>
#include <cstdint>

#include "MemMapping.h"


int main(int argc, char * argv[]) {

    using namespace std::literals::string_literals;
    using namespace std::literals::string_view_literals;

    cxxopts::Options options(
            "FileToSharedMem",
            "FileToSharedMem: copies file content to memory location.\n"
            ""
    );

    options.set_width(160);

    options.add_options()
            ("help", "Display this help", cxxopts::value<bool>()->default_value("false"))
            ("verbose", "Verbose output", cxxopts::value<bool>()->default_value("true"))
            ("file", "Set binary file path", cxxopts::value<std::string>()->default_value("Project.bin"))
            ("addr", "Set memory physical address", cxxopts::value<std::string>()->default_value("0xa6000000"));

    auto result = options.parse(argc, argv);

    if (result["help"].as<bool>())
        return not( std::cout << options.help() << std::endl );


    std::string file_path = result["file"].as<std::string>();   
    uint64_t addr = std::stoull(result["addr"].as<std::string>(), nullptr, 0);

    std::ifstream fin(file_path, std::ios::in | std::ios::binary);

    if(!fin)
    {
        fprintf(stderr, "Couldn't open file %s", file_path);
		exit(1);
    }

    //service fields in shared mem
    struct 
    {
        uint32_t len;
        uint32_t mark;
    } service = {.len = std::filesystem::file_size(file_path), .mark = 0};

    const int accessQuant = 8;
    const int map_len = service.len + sizeof(service) + accessQuant; //с небольшим запасом

    MemMapping map(O_RDWR | O_SYNC, addr, map_len, PROT_READ | PROT_WRITE, MAP_SHARED);

    void * pDst = map.get();

    memcpy(pDst, &service, sizeof(service));
    pDst += sizeof(service);

    {
        const uint32_t mask = accessQuant - 1;
        const int buf_len = (service.len & mask) ? ((service.len & ~mask) + accessQuant) : service.len;

        std::vector<char> buf(buf_len);
        if(!fin.read(buf.data(), service.len))
        {
            fprintf(stderr, "Couldn't read from file");
            exit(1); 
        }    
      
        memcpy(pDst, buf.data(), buf.size());

        // По одному байту работает, но некрасиво
        //
        // int i;
        // char * p = (char *)pDst;
        // const char * pSrc = buf.data();
        // for(i = 0; i < service.len; i++)
        //     *p++ = *pSrc++;
    }
 
    //Так нельзя - получаем Bus error
    //
    // if(!fin.read((char *)pDst, service.len))
    // {
    //     fprintf(stderr, "Couldn't read from file");
	// 	exit(1); 
    // }

    service.mark = 0x12345678;
    pDst = map.get();
    memcpy(pDst, &service, sizeof(service));


    return 0;
}