JUCE/modules/juce_gui_extra/documents/juce_FileBasedDocument.cpp

/*
  ==============================================================================

   This file is part of the JUCE library.
   Copyright (c) 2017 - ROLI Ltd.

   JUCE is an open source library subject to commercial or open-source
   licensing.

   By using JUCE, you agree to the terms of both the JUCE 5 End-User License
   Agreement and JUCE 5 Privacy Policy (both updated and effective as of the
   27th April 2017).

   End User License Agreement: www.juce.com/juce-5-licence
   Privacy Policy: www.juce.com/juce-5-privacy-policy

   Or: You may also use this code under the terms of the GPL v3 (see
   www.gnu.org/licenses).

   JUCE IS PROVIDED "AS IS" WITHOUT ANY WARRANTY, AND ALL WARRANTIES, WHETHER
   EXPRESSED OR IMPLIED, INCLUDING MERCHANTABILITY AND FITNESS FOR PURPOSE, ARE
   DISCLAIMED.

  ==============================================================================
*/

FileBasedDocument::FileBasedDocument (const String& fileExtension_,
                                      const String& fileWildcard_,
                                      const String& openFileDialogTitle_,
                                      const String& saveFileDialogTitle_)
    : changedSinceSave (false),
      fileExtension (fileExtension_),
      fileWildcard (fileWildcard_),
      openFileDialogTitle (openFileDialogTitle_),
      saveFileDialogTitle (saveFileDialogTitle_)
{
}

FileBasedDocument::~FileBasedDocument()
{
}

//==============================================================================
void FileBasedDocument::setChangedFlag (const bool hasChanged)
{
    if (changedSinceSave != hasChanged)
    {
        changedSinceSave = hasChanged;
        sendChangeMessage();
    }
}

void FileBasedDocument::changed()
{
    changedSinceSave = true;
    sendChangeMessage();
}

//==============================================================================
void FileBasedDocument::setFile (const File& newFile)
{
    if (documentFile != newFile)
    {
        documentFile = newFile;
        changed();
    }
}

//==============================================================================
Result FileBasedDocument::loadFrom (const File& newFile, const bool showMessageOnFailure)
{
    MouseCursor::showWaitCursor();

    const File oldFile (documentFile);
    documentFile = newFile;

    Result result (Result::fail (TRANS("The file doesn't exist")));

    if (newFile.existsAsFile())
    {
        result = loadDocument (newFile);

        if (result.wasOk())
        {
            setChangedFlag (false);
            MouseCursor::hideWaitCursor();

            setLastDocumentOpened (newFile);
            return result;
        }
    }

    documentFile = oldFile;
    MouseCursor::hideWaitCursor();

    if (showMessageOnFailure)
        AlertWindow::showMessageBoxAsync (AlertWindow::WarningIcon,
                                          TRANS("Failed to open file..."),
                                          TRANS("There was an error while trying to load the file: FLNM")
                                              .replace ("FLNM", "\n" + newFile.getFullPathName())
                                            + "\n\n"
                                            + result.getErrorMessage());

    return result;
}

#if JUCE_MODAL_LOOPS_PERMITTED
Result FileBasedDocument::loadFromUserSpecifiedFile (const bool showMessageOnFailure)
{
    FileChooser fc (openFileDialogTitle,
                    getLastDocumentOpened(),
                    fileWildcard);

    if (fc.browseForFileToOpen())
        return loadFrom (fc.getResult(), showMessageOnFailure);

    return Result::fail (TRANS("User cancelled"));
}

static bool askToOverwriteFile (const File& newFile)
{
    return AlertWindow::showOkCancelBox (AlertWindow::WarningIcon,
                                            TRANS("File already exists"),
                                            TRANS("There's already a file called: FLNM")
                                                .replace ("FLNM", newFile.getFullPathName())
                                             + "\n\n"
                                             + TRANS("Are you sure you want to overwrite it?"),
                                            TRANS("Overwrite"),
                                            TRANS("Cancel"));
}

//==============================================================================
FileBasedDocument::SaveResult FileBasedDocument::save (const bool askUserForFileIfNotSpecified,
                                                       const bool showMessageOnFailure)
{
    return saveAs (documentFile,
                   false,
                   askUserForFileIfNotSpecified,
                   showMessageOnFailure);
}

FileBasedDocument::SaveResult FileBasedDocument::saveAs (const File& newFile,
                                                         const bool warnAboutOverwritingExistingFiles,
                                                         const bool askUserForFileIfNotSpecified,
                                                         const bool showMessageOnFailure)
{
    if (newFile == File())
    {
        if (askUserForFileIfNotSpecified)
            return saveAsInteractive (true);

        // can't save to an unspecified file
        jassertfalse;
        return failedToWriteToFile;
    }

    if (warnAboutOverwritingExistingFiles
          && newFile.exists()
          && ! askToOverwriteFile (newFile))
        return userCancelledSave;

    MouseCursor::showWaitCursor();

    const File oldFile (documentFile);
    documentFile = newFile;

    const Result result (saveDocument (newFile));

    if (result.wasOk())
    {
        setChangedFlag (false);
        MouseCursor::hideWaitCursor();

        sendChangeMessage(); // because the filename may have changed
        return savedOk;
    }

    documentFile = oldFile;
    MouseCursor::hideWaitCursor();

    if (showMessageOnFailure)
        AlertWindow::showMessageBoxAsync (AlertWindow::WarningIcon,
                                          TRANS("Error writing to file..."),
                                          TRANS("An error occurred while trying to save \"DCNM\" to the file: FLNM")
                                            .replace ("DCNM", getDocumentTitle())
                                            .replace ("FLNM", "\n" + newFile.getFullPathName())
                                           + "\n\n"
                                           + result.getErrorMessage());

    sendChangeMessage(); // because the filename may have changed
    return failedToWriteToFile;
}

FileBasedDocument::SaveResult FileBasedDocument::saveIfNeededAndUserAgrees()
{
    if (! hasChangedSinceSaved())
        return savedOk;

    const int r = AlertWindow::showYesNoCancelBox (AlertWindow::QuestionIcon,
                                                   TRANS("Closing document..."),
                                                   TRANS("Do you want to save the changes to \"DCNM\"?")
                                                    .replace ("DCNM", getDocumentTitle()),
                                                   TRANS("Save"),
                                                   TRANS("Discard changes"),
                                                   TRANS("Cancel"));

    if (r == 1)  // save changes
        return save (true, true);

    if (r == 2)  // discard changes
        return savedOk;

    return userCancelledSave;
}

File FileBasedDocument::getSuggestedSaveAsFile (const File& defaultFile)
{
    return defaultFile.withFileExtension (fileExtension).getNonexistentSibling (true);
}

FileBasedDocument::SaveResult FileBasedDocument::saveAsInteractive (const bool warnAboutOverwritingExistingFiles)
{
    File f;

    if (documentFile.existsAsFile())
        f = documentFile;
    else
        f = getLastDocumentOpened();

    String legalFilename (File::createLegalFileName (getDocumentTitle()));

    if (legalFilename.isEmpty())
        legalFilename = "unnamed";

    if (f.existsAsFile() || f.getParentDirectory().isDirectory())
        f = f.getSiblingFile (legalFilename);
    else
        f = File::getSpecialLocation (File::userDocumentsDirectory).getChildFile (legalFilename);

    f = getSuggestedSaveAsFile (f);

    FileChooser fc (saveFileDialogTitle, f, fileWildcard);

    if (fc.browseForFileToSave (warnAboutOverwritingExistingFiles))
    {
        File chosen (fc.getResult());
        if (chosen.getFileExtension().isEmpty())
        {
            chosen = chosen.withFileExtension (fileExtension);

            if (chosen.exists() && ! askToOverwriteFile (chosen))
                return userCancelledSave;
        }

        setLastDocumentOpened (chosen);
        return saveAs (chosen, false, false, true);
    }

    return userCancelledSave;
}
#endif