JUCE/modules/juce_gui_extra/documents/juce_FileBasedDocument.cpp

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

   This file is part of the JUCE 6 technical preview.
   Copyright (c) 2017 - ROLI Ltd.

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

   For this technical preview, this file is not subject to commercial licensing.

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

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

namespace juce
{

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

} // namespace juce