#include "filesystemwatcher.h"

#include <QDebug>
#include <QDir>
#include <QFileInfo>
#include <QMainWindow>

#include "mainwindow.h"
#include "ui_mainwindow.h"

extern bool ReLoad;
extern MainWindow* mw_one;
extern QVector<QString> openFileList;

FileSystemWatcher* FileSystemWatcher::m_pInstance = NULL;

FileSystemWatcher::FileSystemWatcher(QObject* parent) : QObject(parent) {}

// 监控文件或目录
void FileSystemWatcher::addWatchPath(QString path) {
  // qDebug() << QString("Add to watch: %1").arg(path);

  if (m_pInstance == NULL) {
    m_pInstance = new FileSystemWatcher();
    m_pInstance->m_pSystemWatcher = new QFileSystemWatcher();

    // 连接QFileSystemWatcher的directoryChanged和fileChanged信号到相应的槽
    connect(m_pInstance->m_pSystemWatcher, SIGNAL(directoryChanged(QString)),
            m_pInstance, SLOT(directoryUpdated(QString)));
    connect(m_pInstance->m_pSystemWatcher, SIGNAL(fileChanged(QString)),
            m_pInstance, SLOT(fileUpdated(QString)));
  }

  // 添加监控路径
  m_pInstance->m_pSystemWatcher->addPath(path);

  // 如果添加路径是一个目录，保存当前内容列表
  QFileInfo file(path);
  if (file.isDir()) {
    const QDir dirw(path);
    m_pInstance->m_currentContentsMap[path] = dirw.entryList(
        QDir::NoDotAndDotDot | QDir::AllDirs | QDir::Files, QDir::DirsFirst);
  }
}

void FileSystemWatcher::removeWatchPath(QString path) {
  m_pInstance->m_pSystemWatcher->removePath(path);
}

// 只要任何监控的目录更新（添加、删除、重命名），就会调用。
void FileSystemWatcher::directoryUpdated(const QString& path) {
  qDebug() << QString("Directory updated: %1").arg(path);

  // 比较最新的内容和保存的内容找出区别(变化)
  QStringList currEntryList = m_currentContentsMap[path];
  const QDir dir(path);

  QStringList newEntryList = dir.entryList(
      QDir::NoDotAndDotDot | QDir::AllDirs | QDir::Files, QDir::DirsFirst);

  QSet<QString> newDirSet;
  QSet<QString> currentDirSet;
#if (QT_VERSION <= QT_VERSION_CHECK(5, 9, 9))
  {
    newDirSet = QSet<QString>::fromList(newEntryList);  //旧
  }
#endif
#if (QT_VERSION >= QT_VERSION_CHECK(5, 15, 0))
  {
    newDirSet = QSet<QString>(newEntryList.begin(),
                              newEntryList.end());  //新
  }
#endif

#if (QT_VERSION <= QT_VERSION_CHECK(5, 9, 9))
  {
    currentDirSet = QSet<QString>::fromList(currEntryList);  //旧
  }
#endif
#if (QT_VERSION >= QT_VERSION_CHECK(5, 15, 0))
  {
    currentDirSet = QSet<QString>(currEntryList.begin(),
                                  currEntryList.end());  //新
  }
#endif

  // 添加了文件
  QSet<QString> newFiles = newDirSet - currentDirSet;
  QStringList newFile = newFiles.values();

  // 文件已被移除
  QSet<QString> deletedFiles = currentDirSet - newDirSet;
  QStringList deleteFile = deletedFiles.values();

  // 更新当前设置
  m_currentContentsMap[path] = newEntryList;

  if (!newFile.isEmpty() && !deleteFile.isEmpty()) {
    // 文件/目录重命名
    if ((newFile.count() == 1) && (deleteFile.count() == 1)) {
      qDebug() << QString("File Renamed from %1 to %2")
                      .arg(deleteFile.first())
                      .arg(newFile.first());
    }
  } else {
    // 添加新文件/目录至Dir
    if (!newFile.isEmpty()) {
      qDebug() << "New Files/Dirs added: " << newFile;

      foreach (QString file, newFile) {
        // 处理操作每个新文件....
      }
    }

    // 从Dir中删除文件/目录
    if (!deleteFile.isEmpty()) {
      qDebug() << "Files/Dirs deleted: " << deleteFile;

      foreach (QString file, deleteFile) {
        // 处理操作每个被删除的文件....
      }
    }
  }
}

// 文件修改时调用
void FileSystemWatcher::fileUpdated(const QString& path) {
  // qDebug() << QString("The file %1 at path %2 is
  // updated").arg(strName).arg(strPath);
  if (mw_one->getMD5(path) == mw_one->getMD5FromList(path)) return;

  QFileInfo fi(path);
  if (fi.exists()) {
    mw_one->ui->lblFileName->setText(tr("The file has been modified by another "
                                        "program. Do you want to reload?") +
                                     "\n\n" + path +
                                     "\nMD5: " + mw_one->getMD5FromList(path) +
                                     " -> " + mw_one->getMD5(path));
    mw_one->ui->frameTip->setHidden(false);
    ReLoad = true;
    mw_one->strModiFile = path;

    bool re = false;
    for (int i = 0; i < mw_one->reLoadByModiList.count(); i++) {
      if (mw_one->reLoadByModiList.at(i) == path) re = true;
    }
    if (!re) mw_one->reLoadByModiList.append(path);
  }
  mw_one->addFilesWatch();
}