#include "scp_client.h"
#include <QFile>
#include <QDebug>
#ifdef Q_OS_UNIX
#include <pwd.h>
#include <grp.h>
#endif
#ifdef _WIN32
#include <winsock2.h>
#include <ws2tcpip.h>
#else
#include <arpa/inet.h>
#include <netinet/in.h>
#include <sys/socket.h>
#include <unistd.h>
#endif
#include "NetMgr.h"
#include <QJsonArray>
#include <QJsonObject>
#include <QtNetwork/QNetworkRequest>
#include "global.h"

ScpClient::ScpClient(QObject *parent)
    : QObject(parent)
{
#ifdef _WIN32
    WSADATA wsadata;
    WSAStartup(MAKEWORD(2,2), &wsadata);
#endif
    m_sock = -1;
    m_session = nullptr;
}

ScpClient::~ScpClient()
{
    disconnectFromHost();
#ifdef _WIN32
    WSACleanup();
#endif
}

void ScpClient::cancel()
{
    m_cancelled.store(true);
}
bool ScpClient::connectToHost(const QString &host,
                              int port,
                              const QString &user,
                              const QString &password,
                              int timeoutMs)
{
    disconnectFromHost();

    m_sock = socket(AF_INET, SOCK_STREAM, 0);
    if (m_sock < 0) {
        emit error("Failed to create socket");
        return false;
    }

    struct sockaddr_in sin{};
    sin.sin_family = AF_INET;
#ifdef _WIN32
    sin.sin_addr.s_addr = inet_addr(host.toUtf8().constData());
#else
    if (inet_pton(AF_INET, host.toUtf8().constData(), &sin.sin_addr) <= 0) {
        emit error("Invalid IP address");
        return false;
    }
#endif
    sin.sin_port = htons(port);

    if (::connect(m_sock, (struct sockaddr*)&sin, sizeof(sin)) != 0) {
        emit error("Failed to connect");
        return false;
    }

    m_session = libssh2_session_init();
    if (!m_session) {
        emit error("Failed to init libssh2 session");
        return false;
    }

    // 阻塞模式
    libssh2_session_set_blocking(m_session, 1);

    if (libssh2_session_handshake(m_session, m_sock) != 0) {
        emit error("Handshake failed");
        return false;
    }

    if (libssh2_userauth_password(
            m_session,
            user.toUtf8().constData(),
            password.toUtf8().constData()) != 0)
    {
        emit error("Authentication failed");
        return false;
    }

    return true;
}

void ScpClient::disconnectFromHost()
{
    m_cancelled.store(true);
    if (m_session) {
        libssh2_session_disconnect(m_session, "Bye");
        libssh2_session_free(m_session);
        m_session = nullptr;
    }

#ifdef _WIN32
    if (m_sock != -1) closesocket(m_sock);
#else
    if (m_sock != -1) close(m_sock);
#endif
    m_sock = -1;
}

bool ScpClient::download(const QString &remotePath, const QString &localPath)
{
    if (!m_session) return false;
    m_cancelled.store(false);

    libssh2_struct_stat st;
    // 使用 scp_recv2 获取远程文件信息
    LIBSSH2_CHANNEL* channel = libssh2_scp_recv2(
                m_session,
                remotePath.toUtf8().constData(),
                &st);

    if (!channel) {
        char *errmsg;
        libssh2_session_last_error(m_session, &errmsg, nullptr, 0);
        emit error(QString("SCP recv failed: %1").arg(errmsg));
        return false;
    }

    QFile file(localPath);
    if (!file.open(QIODevice::WriteOnly)) {
        emit error("Open local file failed");
        libssh2_channel_free(channel);
        return false;
    }

    qint64 totalSize = st.st_size;
    qint64 received = 0;
    char buffer[16384]; // 使用 16KB 固定缓冲区

    while (received < totalSize && !m_cancelled.load()) {
        if (m_cancelled.load()) {
            emit error("Download cancelled");
            break;
        }

        // 计算剩余需要读取的字节数，防止溢出
        int toRead = sizeof(buffer);
        if (totalSize - received < toRead) {
            toRead = totalSize - received;
        }

        ssize_t rc = libssh2_channel_read(channel, buffer, toRead);

        if (rc > 0) {
            file.write(buffer, rc);
            received += rc;
            emit progress(received, totalSize);
        } else if (rc < 0) {
            emit error("Read error during download");
            break;
        } else {
            // rc == 0 意味着服务器提前关闭了流
            break;
        }
    }

    file.flush();
    file.close();

    // 标准清理流程
    libssh2_channel_free(channel);

    if (!m_cancelled.load() && received != totalSize) {
        emit error("File size mismatch (Incomplete download)");
        return false;
    }

    emit finished();
    return received == totalSize;
}

bool ScpClient::upload(const QString &localPath,
                       const QString &remotePath,const QString& fileName,int type,
                       int fileMode)
{
    if (!m_session) return false;
    m_cancelled.store(false);
    m_Type = type;
    m_fileName = fileName;
    QFile file(localPath);
    if (!file.open(QIODevice::ReadOnly)) {
        emit error("Open local file failed");
        return false;
    }

    qint64 fileSize = file.size();
    qint64 sent = 0;

    LIBSSH2_CHANNEL* channel = libssh2_scp_send64(
                m_session,
                remotePath.toUtf8().constData(),
                fileMode,
                fileSize,
                0, 0);
    if (!channel) {
        emit error("SCP send failed");
        return false;
    }

    char buffer[16384];
    while (sent < fileSize) {
        if (m_cancelled.load()) {
            emit error("Upload cancelled");
            break;
        }

        qint64 n = file.read(buffer, sizeof(buffer));
        if (n <= 0) break;

        char* ptr = buffer;
        while (n > 0) {
            ssize_t rc = libssh2_channel_write(channel, ptr, n);
            if (rc <= 0) {
                emit error("Write failed");
                goto cleanup;
            }
            ptr += rc;
            n -= rc;
            sent += rc;

            emit progress(sent, fileSize);
            if(sent == fileSize){
                uploadFinish();
            }
        }
    }

cleanup:
    libssh2_channel_send_eof(channel);
    libssh2_channel_wait_eof(channel);
    libssh2_channel_wait_closed(channel);
    libssh2_channel_free(channel);
    file.close();

    emit finished();
    return sent == fileSize;
}
void ScpClient::uploadFinish(){
    if(m_fileName != ""){
        qDebug() << "uploadFinish" ;
        QJsonObject allObj,cmdBody,temp;
        QJsonArray tempArray;
        if(m_fileName.contains(".json")){
            allObj.insert("cmd", "90");
            temp["fileName"] = m_fileName;
            if(m_Type >= 0)
                temp["content"] = m_Type;
            tempArray.append(temp);
            allObj.insert("cmdBody",tempArray);
        }else{
            allObj.insert("cmd", "46");
            allObj.insert("type", m_Type);
            temp["fileName"] = m_fileName;
            allObj.insert("cmdBody",temp);
        }
        qDebug() << allObj << endl;
        QNetworkRequest req;
        QString sUrl = QString("http://%1/cgi-bin/General.cgi/").arg(IP);
        req.setUrl(sUrl);
        g_NetMgr->PostJson(req,allObj);
        m_fileName = "";
        m_Type = -1;
    }
}
QString ScpClient::uidToName(uint uid)
{
#ifdef Q_OS_UNIX
    struct passwd *pw = getpwuid(uid);
    if (pw)
        return QString::fromLocal8Bit(pw->pw_name);
#endif
    return QString::number(uid);
}

QString ScpClient::gidToName(uint gid)
{
#ifdef Q_OS_UNIX
    struct group *gr = getgrgid(gid);
       if (gr)
           return QString::fromLocal8Bit(gr->gr_name);
       return QString::number(gid);
#endif
    return QString::number(gid);

}

void ScpClient::waitSocket(SOCKET sock)
{
    fd_set fds;
    FD_ZERO(&fds);
    FD_SET(sock, &fds);

    timeval tv;
    tv.tv_sec = 10;
    tv.tv_usec = 0;

    select(0, &fds, &fds, nullptr, &tv);
}

bool ScpClient::listRemoteDir(const QString &path,
                              QVector<RemoteFileInfo> &outList)
{
    outList.clear();

    LIBSSH2_SFTP *sftp = nullptr;

    for (;;) {
        sftp = libssh2_sftp_init(m_session);
        if (sftp)
            break;

        int err = libssh2_session_last_errno(m_session);
        if (err == LIBSSH2_ERROR_EAGAIN) {
            waitSocket(m_sock);   // 必须
            continue;
        }

        qDebug() << "sftp init failed:" << err;
        return false;
    }

    if (!sftp) {
        emit error("sftp init failed");
        return false;
    }

    LIBSSH2_SFTP_HANDLE *dir =
        libssh2_sftp_opendir(sftp, path.toUtf8().constData());
    if (!dir) {
        emit error("sftp opendir failed: " + path);
        libssh2_sftp_shutdown(sftp);
        return false;
    }

    char filename[512];
    LIBSSH2_SFTP_ATTRIBUTES attrs;

    while (true) {
        memset(&attrs, 0, sizeof(attrs));
        int rc = libssh2_sftp_readdir(dir, filename, sizeof(filename), &attrs);
        if (rc <= 0)
            break;

        QString name = QString::fromUtf8(filename);
        if (name == "." || name == "..")
            continue;

        RemoteFileInfo info;
        info.name = name;
        info.size = static_cast<qint64>(attrs.filesize);
        info.permissions = attrs.permissions;
        info.isDir = LIBSSH2_SFTP_S_ISDIR(attrs.permissions);

        if (attrs.mtime) {
            info.lastModified =
                QDateTime::fromSecsSinceEpoch(attrs.mtime);
        }

        info.uid = attrs.uid;
        info.gid = attrs.gid;
        info.owner = uidToName(attrs.uid);
        info.group = gidToName(attrs.gid);

        outList.push_back(info);
    }

    libssh2_sftp_closedir(dir);
    libssh2_sftp_shutdown(sftp);
    QString out;
    if (exec("pwd", out))
       m_currentPath = out.trimmed();
    else
       m_currentPath = "/";
    return true;
}

bool ScpClient::makeRemoteDir(const QString &path, int mode)
{
    LIBSSH2_SFTP *sftp = libssh2_sftp_init(m_session);
    if (!sftp)
        return false;

    int rc = libssh2_sftp_mkdir(
        sftp, path.toUtf8().constData(), mode);

    libssh2_sftp_shutdown(sftp);
    return (rc == 0);
}
bool ScpClient::removeRemoteFile(const QString &path)
{
    LIBSSH2_SFTP *sftp = libssh2_sftp_init(m_session);
    if (!sftp)
        return false;

    int rc = libssh2_sftp_unlink(
        sftp, path.toUtf8().constData());

    libssh2_sftp_shutdown(sftp);
    return (rc == 0);
}
bool ScpClient::removeRemoteDir(const QString &path)
{
    LIBSSH2_SFTP *sftp = libssh2_sftp_init(m_session);
    if (!sftp)
        return false;

    int rc = libssh2_sftp_rmdir(
        sftp, path.toUtf8().constData());

    libssh2_sftp_shutdown(sftp);
    return (rc == 0);
}
bool ScpClient::renameRemote(const QString &oldPath,
                              const QString &newPath)
{
    LIBSSH2_SFTP *sftp = libssh2_sftp_init(m_session);
    if (!sftp)
        return false;

    int rc = libssh2_sftp_rename(
        sftp,
        oldPath.toUtf8().constData(),
        newPath.toUtf8().constData());

    libssh2_sftp_shutdown(sftp);
    return (rc == 0);
}
bool ScpClient::exec(const QString &cmd, QString &output)
{
    LIBSSH2_CHANNEL *channel = libssh2_channel_open_session(m_session);
    if (!channel)
        return false;

    if (libssh2_channel_exec(channel, cmd.toUtf8().constData()) != 0) {
        libssh2_channel_free(channel);
        return false;
    }

    char buffer[4096];
    for (;;) {
        ssize_t n = libssh2_channel_read(channel, buffer, sizeof(buffer));
        if (n <= 0)
            break;
        output.append(QString::fromUtf8(buffer, n));
    }

    libssh2_channel_close(channel);
    libssh2_channel_free(channel);
    return true;
}
bool ScpClient::goUp()
{
    if (m_currentPath.isEmpty() || m_currentPath == "/")
        return true; // 已经在根目录，仍返回 true

    int idx = m_currentPath.lastIndexOf('/');
    if (idx <= 0) {
        m_currentPath = "/";
    } else {
        m_currentPath = m_currentPath.left(idx);
    }

    // 测试能否列出目录，确保路径有效
    QString dummy;
    QString cmd = QString("ls -l %1").arg(m_currentPath);
    if (!exec(cmd, dummy))
        return false;

    return true;
}