#include <qpdf/QPDFCryptoProvider.hh>
#include <stdexcept>

#include <qpdf/QPDFCrypto_native.hh>

std::shared_ptr<QPDFCryptoImpl>
QPDFCryptoProvider::getImpl()
{
    QPDFCryptoProvider& p = getInstance();
    if (p.m->default_provider.empty())
    {
        throw std::logic_error(
            "QPDFCryptoProvider::getImpl called with no default provider.");
    }
    return p.getImpl_internal(p.m->default_provider);
}

std::shared_ptr<QPDFCryptoImpl>
QPDFCryptoProvider::getImpl(std::string const& name)
{
    return getInstance().getImpl_internal(name);
}

template<typename T>
void
QPDFCryptoProvider::registerImpl(std::string const& name)
{
    getInstance().registerImpl_internal<T>(name);
}

void
QPDFCryptoProvider::setDefaultProvider(std::string const& name)
{
    getInstance().setDefaultProvider_internal(name);
}

QPDFCryptoProvider::QPDFCryptoProvider() :
    m(std::make_shared<Members>())
{
    registerImpl_internal<QPDFCrypto_native>("native");
    setDefaultProvider_internal("native");
}

QPDFCryptoProvider&
QPDFCryptoProvider::getInstance()
{
    static QPDFCryptoProvider instance;
    return instance;
}

std::shared_ptr<QPDFCryptoImpl>
QPDFCryptoProvider::getImpl_internal(std::string const& name) const
{
    auto iter = this->m->providers.find(name);
    if (iter == this->m->providers.end())
    {
        throw std::logic_error(
            "QPDFCryptoProvider requested unknown implementation \"" +
            name + "\"");
    }
    return this->m->providers[name]();
}

template<typename T>
void
QPDFCryptoProvider::registerImpl_internal(std::string const& name)
{
    this->m->providers[name] = std::make_shared<T>;

}

void
QPDFCryptoProvider::setDefaultProvider_internal(std::string const& name)
{
    this->m->default_provider = name;
}