////////////////////////////////////////////////////////////////////////
//
// Copyright (C) 2013-2022 The Octave Project Developers
//
// See the file COPYRIGHT.md in the top-level directory of this
// distribution or <https://octave.org/copyright/>.
//
// This file is part of Octave.
//
// Octave is free software: you can redistribute it and/or modify it
// under the terms of the GNU General Public License as published by
// the Free Software Foundation, either version 3 of the License, or
// (at your option) any later version.
//
// Octave is distributed in the hope that it will be useful, but
// WITHOUT ANY WARRANTY; without even the implied warranty of
// MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
// GNU General Public License for more details.
//
// You should have received a copy of the GNU General Public License
// along with Octave; see the file COPYING.  If not, see
// <https://www.gnu.org/licenses/>.
//
////////////////////////////////////////////////////////////////////////

#if defined (HAVE_CONFIG_H)
#  include "config.h"
#endif

#include <QCheckBox>
#include <QComboBox>
#include <QDialogButtonBox>
#include <QDirIterator>
#include <QFileDialog>
#include <QFileInfo>
#include <QGridLayout>
#include <QGroupBox>
#include <QHeaderView>
#include <QIcon>
#include <QLabel>
#include <QLineEdit>
#include <QPushButton>
#include <QStatusBar>
#include <QTableView>
#include <QTextStream>
#include <QTimer>

#include "find-files-dialog.h"
#include "find-files-model.h"
#include "gui-preferences-global.h"
#include "gui-preferences-ff.h"
#include "gui-settings.h"
#include "octave-qobject.h"

namespace octave
{
  find_files_dialog::find_files_dialog (QWidget *p, base_qobject& oct_qobj)
    : QDialog (p), m_octave_qobj (oct_qobj)
  {
    resource_manager& rmgr = m_octave_qobj.get_resource_manager ();

    setWindowTitle (tr ("Find Files"));
    setWindowIcon (rmgr.icon ("edit-find"));

    m_dir_iterator = nullptr;

    m_timer = new QTimer (this);
    connect (m_timer, &QTimer::timeout,
             this, &find_files_dialog::look_for_files);

    gui_settings settings;

    QLabel *file_name_label = new QLabel (tr ("Named:"));
    m_file_name_edit = new QLineEdit;
    m_file_name_edit->setToolTip (tr ("Enter the filename search expression"));

    m_file_name_edit->setText (settings.value (ff_file_name).toString ());
    file_name_label->setBuddy (m_file_name_edit);

    QLabel *start_dir_label = new QLabel (tr ("Start in:"));

    m_start_dir_edit = new QLineEdit;
    m_start_dir_edit->setText (settings.value (ff_start_dir.key,
                                               QDir::currentPath ()).toString ());
    m_start_dir_edit->setToolTip (tr ("Enter the start directory"));
    start_dir_label->setBuddy (m_start_dir_edit);

    m_browse_button = new QPushButton (tr ("Browse..."));
    m_browse_button->setToolTip (tr ("Browse for start directory"));
    connect (m_browse_button, &QPushButton::clicked,
             this, &find_files_dialog::browse_folders);

    m_recurse_dirs_check = new QCheckBox (tr ("Search subdirectories"));
    m_recurse_dirs_check->setChecked (settings.value (ff_recurse_dirs).toBool ());
    m_recurse_dirs_check->setToolTip (tr ("Search recursively through directories for matching files"));

    m_include_dirs_check = new QCheckBox (tr ("Include directory names"));
    m_include_dirs_check->setChecked (settings.value (ff_include_dirs).toBool ());
    m_include_dirs_check->setToolTip (tr ("Include matching directories in search results"));

    m_name_case_check = new QCheckBox (tr ("Name case insensitive"));
    m_name_case_check->setChecked (settings.value (ff_name_case).toBool ());
    m_name_case_check->setToolTip (tr ("Set matching name is case insensitive"));

    m_contains_text_check = new QCheckBox (tr ("Contains text:"));
    m_contains_text_check->setToolTip (tr ("Enter the file content search expression"));
    m_contains_text_check->setChecked (settings.value (ff_check_text).toBool ());

    m_contains_text_edit = new QLineEdit ();
    m_contains_text_edit->setToolTip (tr ("Text to match"));
    m_contains_text_edit->setText (settings.value (ff_contains_text).toString ());

    m_content_case_check = new QCheckBox (tr ("Text case insensitive"));
    m_content_case_check->setChecked (settings.value (ff_content_case).toBool ());
    m_content_case_check->setToolTip (tr ("Set text content is case insensitive"));

    find_files_model *model = new find_files_model (this);

    m_file_list = new QTableView;
    m_file_list->setWordWrap (false);
    m_file_list->setModel (model);
    m_file_list->setShowGrid (false);
    m_file_list->setSelectionBehavior (QAbstractItemView::SelectRows);
    m_file_list->setSelectionMode (QAbstractItemView::SingleSelection);
    m_file_list->setAlternatingRowColors (true);
    m_file_list->setToolTip (tr ("Search results"));
    m_file_list->setSortingEnabled (true);
    m_file_list->horizontalHeader ()->restoreState (settings.value (ff_column_state.key).toByteArray ());
    m_file_list->horizontalHeader ()->setSortIndicatorShown (true);
    m_file_list->horizontalHeader ()->setSectionsClickable (true);
    m_file_list->horizontalHeader ()->setStretchLastSection (true);
    m_file_list->sortByColumn (settings.value (ff_sort_files_by_column).toInt (),
                               static_cast<Qt::SortOrder>
                               (settings.value (ff_sort_files_by_order).toUInt ()));
                // FIXME: use value<Qt::SortOrder> instead of static cast after
                //        dropping support of Qt 5.4

    connect (m_file_list, &QTableView::doubleClicked,
             this, &find_files_dialog::item_double_clicked);

    m_status_bar = new QStatusBar;
    m_status_bar->showMessage (tr ("Idle."));

    m_find_button = new QPushButton (tr ("Find"));
    m_find_button->setToolTip (tr ("Start search for matching files"));
    connect (m_find_button, &QPushButton::clicked,
             this, &find_files_dialog::start_find);

    m_stop_button = new QPushButton (tr ("Stop"));
    m_stop_button->setToolTip (tr ("Stop searching"));
    m_stop_button->setEnabled (false);
    connect (m_stop_button, &QPushButton::clicked,
             this, &find_files_dialog::stop_find);

    // layout everything
    QDialogButtonBox *button_box = new QDialogButtonBox (Qt::Vertical);
    button_box->addButton (m_find_button, QDialogButtonBox::ActionRole);
    button_box->addButton (m_stop_button, QDialogButtonBox::ActionRole);

    // add dialog close button
    m_close_button = button_box->addButton (QDialogButtonBox::Close);
    connect (button_box, &QDialogButtonBox::rejected,
             this, &find_files_dialog::close);

    // name options
    QGroupBox *name_group = new QGroupBox (tr ("Filename/location"));
    QGridLayout *name_layout = new QGridLayout;
    name_group->setLayout (name_layout);

    name_layout->addWidget (file_name_label, 1, 1, 1, 1);
    name_layout->addWidget (m_file_name_edit, 1, 2, 1, -1);

    name_layout->addWidget (start_dir_label, 2, 1);
    name_layout->addWidget (m_start_dir_edit, 2, 2, 1, 3);
    name_layout->addWidget (m_browse_button, 2, 5);
    name_layout->setColumnStretch (2, 1);

    name_layout->addWidget (m_recurse_dirs_check, 3, 1);
    name_layout->addWidget (m_include_dirs_check, 3, 2);
    name_layout->addWidget (m_name_case_check, 3, 3);

    // content options
    QGroupBox *content_group = new QGroupBox (tr ("File contents"));
    QGridLayout *content_layout = new QGridLayout;
    content_group->setLayout (content_layout);
    content_layout->addWidget (m_contains_text_check, 4, 1);
    content_layout->addWidget (m_contains_text_edit, 4, 2, 1, 3);
    content_layout->setColumnStretch (2, 1);
    content_layout->addWidget (m_content_case_check, 5, 1);

    QGridLayout *main_layout = new QGridLayout;
    main_layout->setSizeConstraint (QLayout::SetFixedSize);
    main_layout->addWidget (name_group, 0, 0);
    main_layout->addWidget (content_group, 1, 0);
    main_layout->addWidget (button_box, 0, 1, 3, 1);
    main_layout->addWidget (m_file_list, 2, 0);
    main_layout->setRowStretch (2, 1);
    main_layout->addWidget (m_status_bar, 3, 0, 1, -1);

    setLayout (main_layout);

    connect (this, &find_files_dialog::finished,
             this, &find_files_dialog::handle_done);
  }

  find_files_dialog::~find_files_dialog (void)
  {
    delete m_dir_iterator;
  }

  void find_files_dialog::save_settings (void)
  {
    gui_settings settings;

    int sort_column = m_file_list->horizontalHeader ()->sortIndicatorSection ();
    Qt::SortOrder sort_order
      = m_file_list->horizontalHeader ()->sortIndicatorOrder ();
    settings.setValue (ff_sort_files_by_column.key, sort_column);
    settings.setValue (ff_sort_files_by_order.key, sort_order);
    settings.setValue (ff_column_state.key, m_file_list->horizontalHeader ()->saveState ());

    settings.setValue (ff_file_name.key, m_file_name_edit->text ());

    settings.setValue (ff_start_dir.key, m_start_dir_edit->text ());

    settings.setValue (ff_recurse_dirs.key, m_recurse_dirs_check->text ());
    settings.setValue (ff_include_dirs.key, m_include_dirs_check->text ());
    settings.setValue (ff_name_case.key, m_name_case_check->text ());

    settings.setValue (ff_contains_text.key, m_contains_text_edit->text ());
    settings.setValue (ff_check_text.key, m_contains_text_check->isChecked ());
    settings.setValue (ff_content_case.key, m_content_case_check->isChecked ());

    settings.sync ();
  }

  void find_files_dialog::set_search_dir (const QString& dir)
  {
    stop_find ();
    m_start_dir_edit->setText (dir);
  }

  void find_files_dialog::start_find (void)
  {
    stop_find ();

    find_files_model *m = static_cast<find_files_model *> (m_file_list->model ());
    m->clear ();

    QDirIterator::IteratorFlags flags = QDirIterator::NoIteratorFlags;
    if (m_recurse_dirs_check->isChecked ())
      flags |= QDirIterator::Subdirectories;

    QDir::Filters filters = QDir::Dirs | QDir::NoDotAndDotDot | QDir::Files;
    if (! m_name_case_check->isChecked ())
      filters |= QDir::CaseSensitive;

    QStringList nameFilters;
    nameFilters.append (m_file_name_edit->text ());

    if (m_dir_iterator)
      delete m_dir_iterator;

    m_dir_iterator = new QDirIterator (m_start_dir_edit->text (), nameFilters,
                                       filters, flags);

    // enable/disable widgets
    m_find_button->setEnabled (false);
    m_stop_button->setEnabled (true);
    m_close_button->setEnabled (false);
    m_browse_button->setEnabled (false);
    m_start_dir_edit->setEnabled (false);
    m_file_name_edit->setEnabled (false);
    m_recurse_dirs_check->setEnabled (false);
    m_include_dirs_check->setEnabled (false);
    m_name_case_check->setEnabled (false);
    m_contains_text_check->setEnabled (false);
    m_content_case_check->setEnabled (false);
    m_contains_text_edit->setEnabled (false);

    m_status_bar->showMessage (tr ("Searching..."));
    m_timer->start (0);
  }

  void find_files_dialog::stop_find (void)
  {
    m_timer->stop ();

    m_find_button->setEnabled (true);
    m_stop_button->setEnabled (false);
    m_close_button->setEnabled (true);
    m_browse_button->setEnabled (true);
    m_start_dir_edit->setEnabled (true);
    m_file_name_edit->setEnabled (true);
    m_recurse_dirs_check->setEnabled (true);
    m_include_dirs_check->setEnabled (true);
    m_name_case_check->setEnabled (true);
    m_contains_text_check->setEnabled (true);
    m_content_case_check->setEnabled (true);
    m_contains_text_edit->setEnabled (true);

    find_files_model *m = static_cast<find_files_model *> (m_file_list->model ());
    QString res_str = QString (tr ("%1 match (es)")).arg (m->rowCount ());

    m_status_bar->showMessage (res_str);
  }

  void find_files_dialog::browse_folders (void)
  {
    int opts = 0;  // No options by default.

    // FIXME: Remove, if for all common KDE versions (bug #54607) is resolved.

    gui_settings settings;

    if (! settings.value (global_use_native_dialogs).toBool ())
      opts = QFileDialog::DontUseNativeDialog;

    QString dir =
      QFileDialog::getExistingDirectory (this, tr ("Set search directory"),
                                         m_start_dir_edit->text (),
                                         QFileDialog::Option (opts));

    if (! dir.isEmpty ())
      m_start_dir_edit->setText (dir);
  }

  void find_files_dialog::item_double_clicked (const QModelIndex& idx)
  {
    find_files_model *m = static_cast<find_files_model *> (m_file_list->model ());

    QFileInfo info = m->fileInfo (idx);

    if (idx.column () == 1)
      {
        // clicked in directory part
        emit dir_selected (info.absolutePath ());
      }
    else
      {
        // clicked in filename part
        if (info.isDir ())
          emit dir_selected (info.absoluteFilePath ());
        else
          emit file_selected (info.absoluteFilePath ());
      }
  }

  void find_files_dialog::look_for_files (void)
  {
    if (m_dir_iterator && m_dir_iterator->hasNext ())
      {
        QFileInfo info (m_dir_iterator->next ());

        find_files_model *m
          = static_cast<find_files_model *> (m_file_list->model ());

        if (is_match (info))
          m->addFile (info);
      }
    else
      {
        stop_find ();
      }
  }

  void find_files_dialog::handle_done (int)
  {
    // make sure we stopped processing
    stop_find ();
  }

  bool find_files_dialog::is_match (const QFileInfo& info)
  {
    bool match = true;
    if (info.isDir ())
      {
        if (! m_include_dirs_check->isChecked ()) match = false;
        if (m_contains_text_check->isChecked ()) match = false;
      }
    else
      {
        // a file
        if (m_contains_text_check->isChecked ())
          {
            match = false;

            QFile file (info.absoluteFilePath ());
            if (file.open (QIODevice::ReadOnly))
              {
                QTextStream stream (&file);

                QString line;
                QString match_str = m_contains_text_edit->text ();

                Qt::CaseSensitivity cs = m_content_case_check->isChecked ()
                                         ? Qt::CaseInsensitive
                                         : Qt::CaseSensitive;

                do
                  {
                    line = stream.readLine ();
                    match = line.contains (match_str, cs);
                  }
                while (! line.isNull () && match == false);
              }

          }
      }

    return match;
  }
}