#include "DatabaseManager.h"
#include "Constant.h"
#include "Log.h"
#include <QCoreApplication>
#include <QMutex>
#include <QtSql/QSqlError>
#include <QtSql/QSqlQuery>

DatabaseManager* DatabaseManager::instance = nullptr;

DatabaseManager::DatabaseManager()
{
    if (QSqlDatabase::contains("qt_sql_default_connection")) {
        db = QSqlDatabase::database("qt_sql_default_connection");
    } else {
        db = QSqlDatabase::addDatabase("QSQLITE");
        db.setDatabaseName(Constant::DatabasePath);
    }
}

DatabaseManager::~DatabaseManager()
{
    db.close();
}

DatabaseManager* DatabaseManager::getInstace()
{
    if (instance == nullptr) {
        static QMutex mutex;
        QMutexLocker locker(&mutex);
        if (instance == nullptr) {
            instance = new DatabaseManager();
        }
    }
    return instance;
}

/**
 * @brief 打开数据库
 * @return
 */
bool DatabaseManager::open()
{
    if (!db.open()) {
        Log::error("database open failed");
        qDebug() << db.lastError();
        return false;
    }
    Log::info("database open success");
    return true;
}

/**
 * @brief 关闭数据库
 */
void DatabaseManager::close()
{
    if (db.isOpen())
        db.close();
}

/**
 * @brief 添加数据
 * @param file
 */
bool DatabaseManager::insert(File file)
{
    QSqlQuery query;
    query.prepare("insert into file (channel, datetime, filename) values (?, ?, ?)");
    query.addBindValue(file.channel);
    query.addBindValue(file.datetime);
    query.addBindValue(file.filename);
    if (query.exec()) {
        return true;
    } else {
        Log::error("insert one record into database failed, reason: {}",
            query.lastError().databaseText().toStdString() + "," + query.lastError().driverText().toStdString());
        return false;
    }
}

/**
 * @brief 查询数据
 * @param params 参数
 * @return
 */
QList<DatabaseManager::File> DatabaseManager::get(QVariantMap params)
{
    QList<DatabaseManager::File> result;
    QSqlQuery query;
    QString sql = "select * from file where channel=? and datetime like \'%1\'";
    QString year = params.value("year").toString();
    QString month = params.value("month").toString();
    QString day = params.value("day").toString();
    Channel chn = static_cast<Channel>(params.value("channel").toInt());
    if (year.isEmpty() || month.isEmpty() || day.isEmpty() || (chn != MainChannel && chn != SecondaryChannel)) {
        Log::error("select from database error, params error");
        return result;
    }
    query.prepare(sql);
    query.bindValue(0, chn);
    query.bindValue(1, QString("%1-%2-%3%"));
    if (query.exec()) {
        while (query.next()) {
            DatabaseManager::File file;
            file.id = query.value("id").toInt();
            file.channel = static_cast<DatabaseManager::Channel>(query.value("channel").toInt());
            file.datetime = query.value("datetime").toString();
            file.filename = query.value("filename").toString();
            result.push_back(file);
        }
    } else {
        Log::error("select from database failed, reason: {}",
            query.lastError().databaseText().toStdString());
    }
    Log::info("record of one day: {}", result.length());
    return result;
}

/**
 * @brief 获取某个通道的所有文件列表
 * @param chn
 * @return
 */
QList<DatabaseManager::File> DatabaseManager::get(DatabaseManager::Channel chn)
{
    QList<DatabaseManager::File> result;
    QSqlQuery query;
    QString sql = "select * from file where channel=?";
    query.prepare(sql);
    query.bindValue(0, chn);
    if (query.exec()) {
        while (query.next()) {
            DatabaseManager::File file;
            file.id = query.value("id").toInt();
            file.channel = static_cast<DatabaseManager::Channel>(query.value("channel").toInt());
            file.datetime = query.value("datetime").toString();
            file.filename = query.value("filename").toString();
            result.push_back(file);
        }
    } else {
        Log::error("select from database failed, reason: {}",
            query.lastError().databaseText().toStdString());
    }
    return result;
}
/**
 * @brief 获取前两条记录
 */
QList<DatabaseManager::File> DatabaseManager::getTopTwo()
{
    QList<DatabaseManager::File> result;
    QSqlQuery query;
    query.prepare("select * from file limit 0,2");
    if (query.exec()) {
        while (query.next()) {
            DatabaseManager::File file;
            file.id = query.value("id").toInt();
            file.channel = static_cast<DatabaseManager::Channel>(query.value("channel").toInt());
            file.datetime = query.value("datetime").toString();
            file.filename = query.value("filename").toString();
            result.push_back(file);
        }
    } else {
        Log::error("select top two records from database failed, reason: {}",
            query.lastError().databaseText().toStdString());
    }
    return result;
}

/**
 * @brief 获取所有的年份
 * @return
 */
QStringList DatabaseManager::getAllYears(Channel chn)
{
    QStringList result;
    QSqlQuery query;
    query.prepare(R"(
        select distinct strftime('%Y', datetime) as year
        from file
        order by year
    )");
    if (query.exec()) {
        while (query.next()) {
            QString year = query.value(0).toString();
            result.push_back(year);
        }
    } else {
        Log::error("select all years from database failed, reason: {}",
            query.lastError().databaseText().toStdString());
    }
    Log::info("number of year: {}", result.length());
    return result;
}

/**
 * @brief 获取某年所有的月份
 * @param year
 * @return
 */
QStringList DatabaseManager::getAllMonths(Channel chn, QString year)
{
    QStringList result;
    QSqlQuery query;
    query.prepare(R"(
        select distinct strftime('%m', datetime) as month
        from file
        where channel = ? and strftime('%Y', datetime) = '?'
        order by month 
    )");
    query.bindValue(0, chn);
    query.bindValue(1, year);
    if (query.exec()) {
        while (query.next()) {
            QString month = query.value(0).toString();
            result.push_back(month);
        }
    } else {
        Log::error("select all months of one year from database failed, reason: {}",
            query.lastError().databaseText().toStdString());
    }
    Log::info("number of month: {}", result.length());
    return result;
}

/**
 * @brief 某年某月的天数
 * @param year
 * @param month
 * @return
 */
QStringList DatabaseManager::getAllDays(Channel chn, QString year, QString month)
{
    QStringList result;
    QSqlQuery query;
    query.prepare(R"(
        select distinct strftime('%d', datetime) as day
        from file
        where channel = ? 
        and strftime('%Y', datetime) = '?'
        and strftime('%m', datetime) = '?'
        order by day 
    )");
    query.bindValue(0, chn);
    query.bindValue(1, year);
    query.bindValue(2, month);
    if (query.exec()) {
        while (query.next()) {
            QString day = query.value(0).toString();
            result.push_back(day);
        }
    } else {
        Log::error("select all days of one month from database failed, reason: {}",
            query.lastError().databaseText().toStdString());
    }
    Log::info("number of day: {}", result.length());
    return result;
}

/**
 * @brief 根据通道和文件名删除记录，文件名格式yyyyMMddhhmmss
 * @param id
 * @return
 */
bool DatabaseManager::remove(DatabaseManager::Channel chn, QString name)
{
    int id = -1;
    // 找到对应记录
    QSqlQuery query;
    query.prepare("select * from file where channel = ? and filename = ?");
    query.bindValue(0, chn);
    query.bindValue(1, name);
    if (query.exec()) {
        while (query.next()) {
            id = query.value(0).toInt();
            break;
        }
    } else {
        Log::info("cannot find the record, channel = {}, name = {}",
            int(chn),
            name.toStdString());
        return false;
    }
    // 未找到
    if (id == -1) {
        Log::info("cannot find the record, channel = {}, name = {}",
            int(chn),
            name.toStdString());
        return false;
    }
    Log::info("find the record, channel = {} , name = {}, and the id = {}",
        int(chn),
        name.toStdString(),
        id);
    query.clear();
    // 删除文件
    query.prepare("delete from file where id = ?");
    query.bindValue(0, id);
    if (query.exec()) {
        Log::info("delete one record from database, id = {}, channel = {}, name = {}",
            id,
            int(chn),
            name.toStdString());
        return true;
    } else {
        Log::error("delete one record from database failed, channel = {}, name = {}, reason: {}",
            (int)chn,
            name.toStdString(),
            query.lastError().driverText().toStdString() + ", " + query.lastError().databaseText().toStdString());
        return false;
    }
}