#include "sqliteread.h"
#include <QtConcurrent>
SQLiteReadWrite::SQLiteReadWrite(QObject *parent)
    : QObject(parent)
{
    m_connectionName = QString("SQLiteConnection_%1").arg(reinterpret_cast<quintptr>(this));
    idValue = 0;
    m_stopRequested = false;

}

SQLiteReadWrite::~SQLiteReadWrite()
{
    if (!m_isClosed) {
        closeDatabase();
    }
    QCoreApplication::processEvents(QEventLoop::ExcludeUserInputEvents);

}

bool SQLiteReadWrite::openDatabase(const QString &dbPath)
{
    QMutexLocker locker(&m_mutex);

    if (!m_isClosed) {
        closeDatabase();
    }

    // 确定数据库路径
    QString path = dbPath;
    if (path.isEmpty()) {
        QString appDir = QCoreApplication::applicationDirPath();
        path = QDir(appDir).filePath("test_readwrite.db");
    }

    m_dbPath = path;

    // 打开数据库
    m_database = QSqlDatabase::addDatabase("QSQLITE", m_connectionName);
    m_database.setDatabaseName(m_dbPath);

    if (!m_database.open()) {
        log(QString("打开数据库失败: %1").arg(m_database.lastError().text()));
        return false;
    }

    // 启用外键和WAL模式（提高并发性能）
    QSqlQuery query(m_database);
    // 开启外键约束
    if (!query.exec("PRAGMA foreign_keys = ON;")) {
        log(QString("启用外键失败: %1").arg(query.lastError().text()));
    }

    // 开启WAL模式（写时复制，提高读写并发性能）
    if (!query.exec("PRAGMA journal_mode = WAL;")) {
        log(QString("启用WAL模式失败: %1").arg(query.lastError().text()));
    }

//    // 设置同步模式（在安全性和性能之间权衡）
//    if (!query.exec("PRAGMA synchronous = NORMAL;")) {
//        log(QString("设置同步模式失败: %1").arg(query.lastError().text()));
//    }

    // 设置缓存大小
    if (!query.exec("PRAGMA cache_size = 10000;")) {
        log(QString("设置缓存大小失败: %1").arg(query.lastError().text()));
    }

    m_isClosed = false;
    log(QString("数据库打开成功: %1").arg(m_dbPath));
    return true;
}

void SQLiteReadWrite::closeDatabase()
{
    QMutexLocker locker(&m_mutex);

    if (m_isClosed) {
        return;
    }
    m_isClosed = true;

    if (m_database.isOpen()) {
        m_database.close();
        log("数据库已关闭");
    }
    if (QSqlDatabase::contains(m_connectionName)) {
        QSqlDatabase::removeDatabase(m_connectionName);
    }
    QCoreApplication::processEvents(QEventLoop::ExcludeUserInputEvents);
}


void SQLiteReadWrite::startReadWriteOperation()
{
    if (!m_database.isOpen()) {
        emit operationCompleted(false, "数据库未打开");
        return;
    }

    m_stopRequested = false;
    //在单独的线程中执行，避免阻塞UI
    QtConcurrent::run(this, &SQLiteReadWrite::processReadWrite);
}

void SQLiteReadWrite::stopOperation()
{
    m_stopRequested = true;
    log("stop requese send");
}

void SQLiteReadWrite::processReadWrite()
{
    m_timer.start();
    log("开始边读边写操作...");
    try {
        processWithMultipleConnections();
        if (!m_stopRequested) {
            qint64 elapsed = m_timer.elapsed();
            QString message = QString("操作完成，总耗时: %1 毫秒").arg(elapsed);
            log(message);
            emit operationCompleted(true, message);
        } else {
            emit operationCompleted(false, "quxiao");
        }

    } catch (const std::exception &e) {
        log(QString("发生异常: %1").arg(e.what()));
        emit operationCompleted(false, QString("异常: %1").arg(e.what()));
    }
}


void SQLiteReadWrite::processWithMultipleConnections()
{
    const QString readConnName = m_connectionName + "_read";

    int totalRecords = 0;
    int processedRecords = 0;
    bool readSuccess = false;

    {
        QSqlDatabase readDb = QSqlDatabase::addDatabase("QSQLITE", readConnName);
        readDb.setDatabaseName(m_dbPath);

        if (!readDb.open()) {
            QString logMsg = QString("打开读取连接失败: %1").arg(readDb.lastError().text());
            log(logMsg.toUtf8().constData());
            emit operationCompleted(false, "无法打开数据库连接");
            return;
        }

        {
            QSqlQuery optimizeQuery(readDb);
            optimizeQuery.exec("PRAGMA journal_mode = WAL;");
            optimizeQuery.exec("PRAGMA synchronous = OFF;");
            optimizeQuery.exec("PRAGMA cache_size = -200000;"); // 200MB缓存
            optimizeQuery.exec("PRAGMA temp_store = MEMORY;");
            optimizeQuery.exec("PRAGMA mmap_size = 2147483648;"); // 2GB内存映射
            optimizeQuery.exec("PRAGMA query_only = ON;");
            optimizeQuery.finish();
        }

        {
            QSqlQuery countQuery(readDb);
            if (countQuery.exec("SELECT COUNT(*) FROM lmdatainfov2")) {
                countQuery.next();
                totalRecords = countQuery.value(0).toInt();
            }
            countQuery.finish();
        }

        if (totalRecords == 0) {
            log("数据库中无记录");
            readDb.close();
            emit operationCompleted(false, "数据库中无有效数据");
            return;
        }

        QString totalMsg = QString("GVF数据库总记录数: %1 条").arg(totalRecords);
        log(totalMsg.toUtf8().constData());

        const int pageSize = 200;
        int lastId = 0;

        m_DataBaseList.clear();
        m_DataBaseList.reserve(totalRecords);

        while (!m_stopRequested) {
            QSqlQuery readQuery(readDb);
            readQuery.setForwardOnly(true);
            readQuery.prepare("SELECT id, data FROM lmdatainfov2 WHERE id > :lastId ORDER BY id LIMIT :limit");
            readQuery.bindValue(":lastId", lastId);
            readQuery.bindValue(":limit", pageSize);

            if (!readQuery.exec()) {
                QString errMsg = QString("数据读取失败: %1").arg(readQuery.lastError().text());
                log(errMsg.toUtf8().constData());
                readQuery.finish();
                break;
            }

            int pageRecords = 0;
            while (readQuery.next() && !m_stopRequested) {
                DataBaseStruct data;
                data.id = readQuery.value(0).toInt();
                data.data = readQuery.value(1).toByteArray();
                m_DataBaseList.append(data);
                lastId = data.id;
                pageRecords++;
            }

            readQuery.finish();
            readQuery.clear();

            if (pageRecords == 0) {
                break;
            }

            processedRecords += pageRecords;
            int remainingRecords = totalRecords - processedRecords;
            int progress = (processedRecords * 100) / totalRecords;
            emit progressUpdated(progress, processedRecords, totalRecords);
        }

        QCoreApplication::processEvents(QEventLoop::ExcludeUserInputEvents);
        readDb.close();
        readSuccess = true;
    }

    QThread::msleep(50);

    if (QSqlDatabase::contains(readConnName)) {
        QSqlDatabase::removeDatabase(readConnName);
    }

    QCoreApplication::processEvents(QEventLoop::ExcludeUserInputEvents);
}



QSqlDatabase SQLiteReadWrite::createConnection()
{
    QString connName = QString("TempConnection_%1_%2")
        .arg(m_connectionName)
        .arg(QDateTime::currentMSecsSinceEpoch());

    QSqlDatabase db = QSqlDatabase::addDatabase("QSQLITE", connName);
    db.setDatabaseName(m_dbPath);

    if (!db.open()) {
        log(QString("创建临时连接失败: %1").arg(db.lastError().text()));
    }

    return db;
}


void SQLiteReadWrite::log(const QString &message)
{
    QString timestamp = QDateTime::currentDateTime().toString("hh:mm:ss.zzz");
    QString logMsg = QString("[%1] %2").arg(timestamp).arg(message);

    emit logMessage(logMsg);
}

QVector<DataBaseStruct> SQLiteReadWrite::DataBaseList() const
{
    QMutexLocker locker(&m_mutex);
    return m_DataBaseList;
}

QString SQLiteReadWrite::getMeasureStartTime()
{
    QMutexLocker locker(&m_mutex);
    if (m_isClosed || !m_database.isOpen())
    {
        log("Database not open, cannot read statistic starttime");
        return "";
    }
    QSqlQuery query(m_database);
    // lmstatisticinfov2 存储本次测量标准起止时间
    if (!query.exec("SELECT starttime FROM lmstatisticinfov2 LIMIT 1;"))
    {
        log(QString("Query lmstatisticinfov2 failed: %1").arg(query.lastError().text()));
        return "";
    }
    if (query.next())
    {
        return query.value("starttime").toString();
    }
    log("lmstatisticinfov2 table has no starttime record");
    return "";
}

void SQLiteReadWrite::setIdValue(int value)
{
    idValue = value;
}