#include <string.h>

#include "message_sender.hpp"
#include "message_builder/date.hpp"
#include "message_builder/mail_to.hpp"
#include "message_builder/cc.hpp"
#include "message_builder/subject.hpp"
#include "message_builder/text.hpp"
#include "message_builder/from.hpp"

namespace smtp
{
    static std::string mText = "";

    //
    // Constructors/Destructors
    //
    MessageSender::MessageSender( SettingsStorage const& settings_storage )
        : mSettingsStorage( settings_storage )
    {

    }

    //
    //Public methods
    //
    bool MessageSender::Send( std::string const& mail_from, std::string const& mail_to, std::list<std::string> const& cc,
                             std::string const& subject, std::string const& text )
    {
        CURLcode result = CURLE_OK;

        struct curl_slist *recipients = NULL;
        struct WriteThis upload_ctx;

        upload_ctx.counter = 0;

        auto curl = curl_easy_init();

        if( !curl )
        {
            //Error
            return false;
        }
        mText = GetText( mail_from, mail_to, cc, subject, text);
        FillRecipients( curl, mail_to, cc, recipients );

        curl_easy_setopt(curl, CURLOPT_USERNAME,     mSettingsStorage.username.c_str());
        curl_easy_setopt(curl, CURLOPT_PASSWORD,     mSettingsStorage.password.c_str());
        curl_easy_setopt(curl, CURLOPT_URL,          GetHostPortData().c_str());

        curl_easy_setopt(curl, CURLOPT_USE_SSL,      (long)CURLUSESSL_ALL);
        curl_easy_setopt(curl, CURLOPT_MAIL_FROM,    mail_from.c_str());

        curl_easy_setopt(curl, CURLOPT_READFUNCTION, ReadCallBack);
        curl_easy_setopt(curl, CURLOPT_READDATA,     &upload_ctx);
        curl_easy_setopt(curl, CURLOPT_UPLOAD,       1L);
        curl_easy_setopt(curl, CURLOPT_VERBOSE,      1L);

        result = curl_easy_perform(curl);

        if (result != CURLE_OK)
        {
            fprintf(stderr, "curl_easy_perform() failed: %s\n", curl_easy_strerror(result));
            return false;
        }

        curl_slist_free_all(recipients);
        curl_easy_cleanup(curl);
        return true;
    }

    //
    //Private methods
    //
    std::string MessageSender::GetText( std::string const& mail_from, std::string const& mail_to, std::list<std::string> const& cc,
                                        std::string const& subject, std::string const& text ) const
    {
        auto text_decorator = std::make_shared<message_builder::Text>( text );
        text_decorator->Apply( std::make_shared<message_builder::Subject>( subject ) )
                       .Apply( std::make_shared<message_builder::Cc>( cc ) )
                       .Apply( std::make_shared<message_builder::From>( mail_from ) )
                       .Apply( std::make_shared<message_builder::MailTo>( mail_to ) )
                       .Apply( std::make_shared<message_builder::Date>() );
        return text_decorator->Get();
    }

    void MessageSender::FillRecipients( CURL* curl, std::string const& mail_to, std::list<std::string> const& cc, curl_slist* recipients )
    {
        recipients = curl_slist_append( recipients, mail_to.c_str() );

        for( const auto& recipient : cc )
        {
            recipients = curl_slist_append( recipients, recipient.c_str() );
        }

        curl_easy_setopt( curl, CURLOPT_MAIL_RCPT, recipients );
    }

    std::string MessageSender::GetHostPortData() const
    {
        auto result = "smtp://" + mSettingsStorage.host;
        if( !mSettingsStorage.port.empty() )
        {
            result += ":" + mSettingsStorage.port;
        }
        return result;
    }

    size_t MessageSender::ReadCallBack( void *ptr, size_t size, size_t nmemb, void *userp )
    {
        struct WriteThis *pooh = reinterpret_cast<WriteThis*>( userp );
        if( size * nmemb < 1 )
        {
            return 0;
        }
        if( pooh->counter++ > 0 )
        {
            return 0;
        }
        memcpy( ptr, mText.c_str(), mText.size() );
        return mText.size();
    }
}