#include "database/AlbumRepository.h"

#include <iostream>
#include <algorithm>
#include <memory>
#include <sstream>
#include <string>
#include <cstring>

namespace database {
AlbumRepository::AlbumRepository(const model::BinaryPath& bConf)
    : BaseRepository(bConf)
{ }


std::vector<model::Album> AlbumRepository::retrieveRecords()
{
    auto conn = setupMysqlConnection();
    auto stmt = mysql_stmt_init(conn);

    const std::string query = "SELECT * FROM Album";
    mysql_stmt_prepare(stmt, query.c_str(), query.size());
    mysql_stmt_execute(stmt);

    auto albums = parseRecords(stmt);

    mysql_stmt_close(stmt);
    mysql_close(conn);

    return albums;
}


std::pair<model::Album, int> AlbumRepository::retrieveRecordWithSongCount(model::Album& album, type::AlbumFilter filter = type::AlbumFilter::id)
{
    std::cout << "retrieving album with song count" << std::endl;
    std::stringstream qry;
    auto conn = setupMysqlConnection();
    auto stmt = mysql_stmt_init(conn);

    MYSQL_BIND params[1];
    std::memset(params, 0, sizeof(params));

    qry << "SELECT alb.*, COUNT(*) AS SongCount FROM Album alb LEFT JOIN ";
    qry << "Song sng ON alb.AlbumId=sng.AlbumId WHERE ";

    switch (filter) {
        case type::AlbumFilter::id:
            qry << "sng.AlbumId = ?";

            params[0].buffer_type = MYSQL_TYPE_LONG;
            params[0].buffer = (char*)&album.id;
            params[0].length = 0;
            params[0].is_null = 0;
            break;
        default:
            break;
    }
    qry << " GROUP BY alb.AlbumId LIMIT 1";

    const auto query = qry.str();

    auto status = mysql_stmt_prepare(stmt, query.c_str(), query.size());
    status = mysql_stmt_bind_param(stmt, params);
    status = mysql_stmt_execute(stmt);

    auto albWSC = parseRecordWithSongCount(stmt);

    mysql_stmt_close(stmt);
    mysql_close(conn);

    return albWSC;
}

model::Album AlbumRepository::retrieveRecord(model::Album& album, type::AlbumFilter filter)
{
    std::cout << "retrieving album record" << std::endl;
    std::stringstream qry;
    auto conn = setupMysqlConnection();
    auto stmt = mysql_stmt_init(conn);

    MYSQL_BIND params[1];
    memset(params, 0, sizeof(params));

    qry << "SELECT alb.* FROM Album alb WHERE ";

    auto titleLength = album.title.size();
    switch (filter) {
        case type::AlbumFilter::id:
            qry << "alb.AlbumId = ?";

            params[0].buffer_type = MYSQL_TYPE_LONG;
            params[0].buffer = (char*)&album.id;
            params[0].length = 0;
            params[0].is_null = 0;
            break;
        case type::AlbumFilter::title:
            qry << "alb.Title = ?";

            params[0].buffer_type = MYSQL_TYPE_STRING;
            params[0].buffer = (char*)album.title.c_str();
            params[0].length = &titleLength;
            params[0].is_null = 0;
            break;
        default:
            break;
    }

    qry << " LIMIT 1";

    const auto query = qry.str();
    auto status = mysql_stmt_prepare(stmt, query.c_str(), query.size());
    status = mysql_stmt_bind_param(stmt, params);
    status = mysql_stmt_execute(stmt);

    album = parseRecord(stmt);

    mysql_stmt_close(stmt);
    mysql_close(conn);

    std::cout << "done" << std::endl;

    return album;
}

bool AlbumRepository::doesAlbumExists(const model::Album& album, type::AlbumFilter filter)
{
    auto conn = setupMysqlConnection();
    auto stmt = mysql_stmt_init(conn);

    MYSQL_BIND params[1];
    memset(params, 0, sizeof(params));

    std::stringstream qry;
    qry << "SELECT * FROM Album WHERE ";

    auto titleLength = album.title.size();
    switch (filter) {
        case type::AlbumFilter::id:
            qry << "AlbumId = ?";

            params[0].buffer_type = MYSQL_TYPE_LONG;
            params[0].buffer = (char*)&album.id;
            params[0].length = 0;
            params[0].is_null = 0;
            break;
        case type::AlbumFilter::title:
            qry << "Title = ?";

            params[0].buffer_type = MYSQL_TYPE_STRING;
            params[0].buffer = (char*)album.title.c_str();
            params[0].length = &titleLength;
            params[0].is_null = 0;
            break;
        default:
            break;
    }

    qry << " LIMIT 1";

    const auto query = qry.str();
    auto status = mysql_stmt_prepare(stmt, query.c_str(), query.size());
    status = mysql_stmt_bind_param(stmt, params);
    status = mysql_stmt_execute(stmt);

    std::cout << "the query has been performed" << std::endl;

    ::mysql_stmt_store_result(stmt);
    auto rowCount = ::mysql_stmt_num_rows(stmt);

    ::mysql_stmt_close(stmt);
    ::mysql_close(conn);

    return (rowCount > 0) ? true : false;
}

void AlbumRepository::saveAlbum(const model::Album& album)
{
    std::cout << "beginning to insert album record" << std::endl;

    auto conn = setupMysqlConnection();
    MYSQL_STMT *stmt = mysql_stmt_init(conn);

    const std::string query = "INSERT INTO Album(Title, Artist, Year) VALUES(?, ?, ?)";

    auto status = mysql_stmt_prepare(stmt, query.c_str(), query.size());

    MYSQL_BIND params[3];
    memset(params, 0, sizeof(params));

    params[0].buffer_type = MYSQL_TYPE_STRING;
    params[0].buffer = (char*)album.title.c_str();
    auto titleLength = album.title.size();
    params[0].length= &titleLength;
    params[0].is_null = 0;

    params[1].buffer_type = MYSQL_TYPE_STRING;
    params[1].buffer = (char*)album.artist.c_str();
    auto artistLength = album.artist.size();
    params[1].length = &artistLength;
    params[1].is_null = 0;

    params[2].buffer_type = MYSQL_TYPE_LONG;
    params[2].buffer = (char*)&album.year;
    params[2].length = 0;
    params[2].is_null = 0;

    status = mysql_stmt_bind_param(stmt, params);
    status = mysql_stmt_execute(stmt);

    mysql_stmt_close(stmt);
    mysql_close(conn);

    std::cout << "done inserting album record" << std::endl;
}

void AlbumRepository::deleteAlbum(const model::Album& album, type::AlbumFilter filter = type::AlbumFilter::id)
{
    std::cout << "deleting album record" << std::endl;

    std::stringstream qry;
    auto conn = setupMysqlConnection();
    auto stmt = mysql_stmt_init(conn);

    MYSQL_BIND params[1];
    std::memset(params, 0, sizeof(params));

    qry << "DELETE FROM Album WHERE ";

    switch (filter) {
        case type::AlbumFilter::id:
            qry << "AlbumId = ?";

            params[0].buffer_type = MYSQL_TYPE_LONG;
            params[0].buffer = (char*)&album.id;
            params[0].length = 0;
            params[0].is_null = 0;
            break;
        default:
            break;
    }

    const auto query = qry.str();

    auto status = mysql_stmt_prepare(stmt, query.c_str(), query.size());
    status = mysql_stmt_bind_param(stmt, params);
    status = mysql_stmt_execute(stmt);

    std::cout << "execute delete query" << std::endl;
}


std::vector<model::Album> AlbumRepository::parseRecords(MYSQL_STMT* stmt)
{
    std::cout << "parsing album record" << std::endl;
    mysql_stmt_store_result(stmt);

    std::vector<model::Album> albums;
    albums.reserve(mysql_stmt_num_rows(stmt));

    const auto valAmt = 3;
    unsigned long len[valAmt];
    my_bool nullRes[valAmt];

    for (auto status = 0; status == 0; status = mysql_stmt_next_result(stmt)) {
        if (mysql_stmt_field_count(stmt) > 0) {
            model::Album alb;
            auto metaBuff = metadataBuffer();
            auto bindedValues = valueBind(alb, metaBuff);
            status = mysql_stmt_bind_result(stmt, bindedValues.get());

            while (true) {
                std::cout << "fetching statement result" << std::endl;
                status = mysql_stmt_fetch(stmt);

                if (status == 1 || status == MYSQL_NO_DATA) {
                    break;
                }

                alb.title = std::get<0>(metaBuff);
                alb.artist = std::get<1>(metaBuff);
                albums.push_back(std::move(alb));
            }
        }
        std::cout << "fetching next result" << std::endl;
    }

    return albums;
}


std::pair<model::Album, int> AlbumRepository::parseRecordWithSongCount(MYSQL_STMT *stmt)
{
    std::cout << "parsing album record with song count" << std::endl;
    mysql_stmt_store_result(stmt);
    auto rowCount = mysql_stmt_num_rows(stmt);

    model::Album album;
    auto metaBuff = metadataBuffer();
    int songCount = 0;
    auto val = valueBindWithSongCount(album, metaBuff, songCount);

    if (rowCount == 0) {
        std::cout << "no results" << std::endl;
        return std::make_pair(album, songCount);
    }

    auto status = mysql_stmt_bind_result(stmt, val.get());
    status = mysql_stmt_fetch(stmt);

    album.title = std::get<0>(metaBuff);
    album.artist = std::get<1>(metaBuff);

    std::cout << "done parsing album record with song count" << std::endl;

    auto albWSC = std::make_pair(album, songCount);

    return albWSC;
}


std::shared_ptr<MYSQL_BIND> AlbumRepository::valueBind(model::Album& album, 
        std::tuple<char*, char*>& metadata)
{
    constexpr auto wordLen = 1024;
    constexpr auto valueCount = 4;
    std::shared_ptr<MYSQL_BIND> values((MYSQL_BIND*) std::calloc(valueCount, sizeof(MYSQL_BIND)));

    values.get()[0].buffer_type = MYSQL_TYPE_LONG;
    values.get()[0].buffer = (char*)&album.id;

    values.get()[1].buffer_type = MYSQL_TYPE_STRING;
    values.get()[1].buffer = (char*)std::get<0>(metadata);
    values.get()[1].buffer_length = wordLen;

    values.get()[2].buffer_type = MYSQL_TYPE_STRING;
    values.get()[2].buffer = (char*)std::get<1>(metadata);
    values.get()[2].buffer_length = wordLen;

    values.get()[3].buffer_type = MYSQL_TYPE_LONG;
    values.get()[3].buffer = (char*)&album.year;

    return values;
}

std::shared_ptr<MYSQL_BIND> AlbumRepository::valueBindWithSongCount(model::Album& album, 
        std::tuple<char*, char*>& metadata, int& songCount)
{
    constexpr auto wordLen = 1024;
    constexpr auto valueCount = 5;
    std::shared_ptr<MYSQL_BIND> values((MYSQL_BIND*) std::calloc(valueCount, sizeof(MYSQL_BIND)));

    values.get()[0].buffer_type = MYSQL_TYPE_LONG;
    values.get()[0].buffer = (char*)&album.id;

    values.get()[1].buffer_type = MYSQL_TYPE_STRING;
    values.get()[1].buffer = (char*)std::get<0>(metadata);
    values.get()[1].buffer_length = wordLen;

    values.get()[2].buffer_type = MYSQL_TYPE_STRING;
    values.get()[2].buffer = (char*)std::get<1>(metadata);
    values.get()[2].buffer_length = wordLen;

    values.get()[3].buffer_type = MYSQL_TYPE_LONG;
    values.get()[3].buffer = (char*)&album.year;

    values.get()[4].buffer_type = MYSQL_TYPE_LONG;
    values.get()[4].buffer = (char*)&songCount;

    return values;
}


std::tuple<char*, char*> AlbumRepository::metadataBuffer()
{
    constexpr auto wordLen = 1024;
    char title[wordLen];
    char artist[wordLen];

    return std::make_tuple(title, artist);
}


model::Album AlbumRepository::parseRecord(MYSQL_STMT *stmt)
{
    std::cout << "parsing album record" << std::endl;
    mysql_stmt_store_result(stmt);
    auto rows = mysql_stmt_num_rows(stmt);

    model::Album album;
    auto metaBuff = metadataBuffer();
    auto bindedValues = valueBind(album, metaBuff);
    auto status = mysql_stmt_bind_result(stmt, bindedValues.get());
    status = mysql_stmt_fetch(stmt);
    
    album.title = std::get<0>(metaBuff);
    album.artist = std::get<1>(metaBuff);

    std::cout << "done parsing album record" << std::endl;

    return album;
}
}