#include <iostream>
#include <string>
#include <sstream>
#include <fstream>
#include <stdexcept>
#include <phosphor-logging/log.hpp>
#include "config.h"
#include "version.hpp"
#include <openssl/sha.h>

namespace phosphor
{
namespace software
{
namespace manager
{

using namespace phosphor::logging;

std::string Version::getValue(const std::string& manifestFilePath,
                              std::string key)
{
    key = key + "=";
    auto keySize = key.length();

    if (manifestFilePath.empty())
    {
        log<level::ERR>("Error MANIFESTFilePath is empty");
        throw std::runtime_error("MANIFESTFilePath is empty");
    }

    std::string value{};
    std::ifstream efile;
    std::string line;
    efile.exceptions(std::ifstream::failbit
                     | std::ifstream::badbit
                     | std::ifstream::eofbit);

    // Too many GCC bugs (53984, 66145) to do this the right way...
    try
    {
        efile.open(manifestFilePath);
        while (getline(efile, line))
        {
            if (line.compare(0, keySize, key) == 0)
            {
                value = line.substr(keySize);
                break;
            }
        }
        efile.close();
    }
    catch (const std::exception& e)
    {
        log<level::ERR>("Error in reading MANIFEST file");
    }

    return value;
}

std::string Version::getId(const std::string& version)
{

    if (version.empty())
    {
        log<level::ERR>("Error version is empty");
        throw std::runtime_error("Version is empty");
    }

    unsigned char digest[SHA512_DIGEST_LENGTH];
    SHA512_CTX ctx;
    SHA512_Init(&ctx);
    SHA512_Update(&ctx, version.c_str(), strlen(version.c_str()));
    SHA512_Final(digest, &ctx);
    char mdString[SHA512_DIGEST_LENGTH*2+1];
    for (int i = 0; i < SHA512_DIGEST_LENGTH; i++)
    {
        snprintf(&mdString[i*2], 3, "%02x", (unsigned int)digest[i]);
    }

    // Only need 8 hex digits.
    std::string hexId = std::string(mdString);
    return (hexId.substr(0, 8));
}

std::string Version::getBMCVersion(const std::string& releaseFilePath)
{
    std::string versionKey = "VERSION_ID=";
    std::string version{};
    std::ifstream efile;
    std::string line;
    efile.open(releaseFilePath);

    while (getline(efile, line))
    {
        if (line.substr(0, versionKey.size()).find(versionKey) !=
            std::string::npos)
        {
            std::size_t pos = line.find_first_of('"') + 1;
            version = line.substr(pos, line.find_last_of('"') - pos);
            break;
        }
    }
    efile.close();

    if (version.empty())
    {
        log<level::ERR>("Error BMC current version is empty");
        throw std::runtime_error("BMC current version is empty");
    }

    return version;
}

bool Version::isFunctional()
{
    return versionStr == getBMCVersion(OS_RELEASE_FILE);
}

} // namespace manager
} // namespace software
} // namepsace phosphor