printing: update the coping of bundled templates

This update includes:
- Instead of copyPath() use a new specialized function:
  copy_bundled_templates()
- The new function supports overwriting of templates
in the user path, but only if a template file is read-only
- If the file is RW create a backup of the file in the
form of: <file-name>-User.html
- Collect backup files and store them in a QStringList
which is then shown in a QMessageBox from MainWindow
to notifying the user about the backup

This change allows moving the maintenance of the bundled
templates back to the application developers and contributors
as currently the only one who can edit the templates in the user
path was the user.

Suggested-by: Dirk Hohndel <dirk@hohndel.org>
Signed-off-by: Lubomir I. Ivanov <neolit123@gmail.com>

3 files changed, 48 insertions, 2 deletions

diff --git a/desktop-widgets/mainwindow.cpp b/desktop-widgets/mainwindow.cpp
index 05314af1d..e5739bd47 100644
--- a/desktop-widgets/mainwindow.cpp
+++ b/desktop-widgets/mainwindow.cpp
@@ -256,8 +256,23 @@ MainWindow::MainWindow() : QMainWindow(),
 	connect(geoLookup, SIGNAL(started()),information(), SLOT(disableGeoLookupEdition()));
 	connect(geoLookup, SIGNAL(finished()), information(), SLOT(enableGeoLookupEdition()));
 #ifndef NO_PRINTING
-	// copy the bundled print templates to the user path; no overwriting occurs!
-	copyPath(getPrintingTemplatePathBundle(), getPrintingTemplatePathUser());
+	// copy the bundled print templates to the user path
+	QStringList templateBackupList;
+	QString templatePathUser(getPrintingTemplatePathUser());
+	copy_bundled_templates(getPrintingTemplatePathBundle(), templatePathUser, &templateBackupList);
+	if (templateBackupList.length()) {
+		QMessageBox msgBox(this);
+		templatePathUser.replace("\\", "/");
+		templateBackupList.replaceInStrings(templatePathUser + "/", "");
+		msgBox.setWindowTitle(tr("Template backup created"));
+		msgBox.setText(tr("The following backup printing templates were created:\n\n%1\n\n"
+			"Location:\n%2\n\n"
+			"Please note that as of this version of Subsurface the default templates\n"
+			"are read-only and should not be edited directly, since the application\n"
+			"can overwrite them on startup.").arg(templateBackupList.join("\n")).arg(templatePathUser));
+		msgBox.setStandardButtons(QMessageBox::Ok);
+		msgBox.exec();
+	}
 	set_bundled_templates_as_read_only();
 	find_all_templates();
 #endif
diff --git a/desktop-widgets/templatelayout.cpp b/desktop-widgets/templatelayout.cpp
index ab9b3f09a..f3f3c8be2 100644
--- a/desktop-widgets/templatelayout.cpp
+++ b/desktop-widgets/templatelayout.cpp
@@ -62,6 +62,35 @@ void set_bundled_templates_as_read_only()
 		QFile::setPermissions(pathUser + QDir::separator() + f, QFileDevice::ReadOwner | QFileDevice::ReadUser);
 }
 
+void copy_bundled_templates(QString src, QString dst, QStringList *templateBackupList)
+{
+	QDir dir(src);
+	if (!dir.exists())
+		return;
+	foreach (QString d, dir.entryList(QDir::Dirs | QDir::NoDotAndDotDot)) {
+		QString dst_path = dst + QDir::separator() + d;
+		dir.mkpath(dst_path);
+		copy_bundled_templates(src + QDir::separator() + d, dst_path, templateBackupList);
+	}
+	foreach (QString f, dir.entryList(QDir::Files)) {
+		QFile fileSrc(src + QDir::separator() + f);
+		QFile fileDest(dst + QDir::separator() + f);
+		if (fileDest.exists()) {
+			// if open() fails the file is either locked or r/o. try to remove it and then overwrite
+			if (!fileDest.open(QFile::ReadWrite | QFile::Text)) {
+				fileDest.setPermissions(QFileDevice::WriteOwner | QFileDevice::WriteUser);
+				fileDest.remove();
+			} else { // if the file is not read-only create a backup
+				fileDest.close();
+				const QString targetFile = fileDest.fileName().replace(".html", "-User.html");
+				fileDest.copy(targetFile);
+				*templateBackupList << targetFile;
+			}
+		}
+		fileSrc.copy(fileDest.fileName()); // in all cases copy the file
+	}
+}
+
 TemplateLayout::TemplateLayout(print_options *PrintOptions, template_options *templateOptions) :
 	m_engine(NULL)
 {
diff --git a/desktop-widgets/templatelayout.h b/desktop-widgets/templatelayout.h
index 8ec4eadc7..cb60cc03d 100644
--- a/desktop-widgets/templatelayout.h
+++ b/desktop-widgets/templatelayout.h
@@ -2,6 +2,7 @@
 #ifndef TEMPLATELAYOUT_H
 #define TEMPLATELAYOUT_H
 
+#include <QStringList>
 #include <grantlee_templates.h>
 #include "mainwindow.h"
 #include "printoptions.h"
@@ -13,6 +14,7 @@
 int getTotalWork(print_options *printOptions);
 void find_all_templates();
 void set_bundled_templates_as_read_only();
+void copy_bundled_templates(QString src, QString dst, QStringList *templateBackupList);
 
 extern QList<QString> grantlee_templates, grantlee_statistics_templates;