Merge branch 'qtHelper'

Signed-off-by: Dirk Hohndel <dirk@hohndel.org>

19 files changed, 302 insertions, 252 deletions

diff --git a/Makefile b/Makefile
index 870c832bb..f8770d344 100644
--- a/Makefile
+++ b/Makefile
@@ -69,6 +69,7 @@ SOURCES = \
 	time.c \
 	libdivecomputer.c \
 	qt-gui.cpp \
+	qthelper.cpp \
 	qt-ui/divelistview.cpp \
 	qt-ui/maintab.cpp \
 	qt-ui/mainwindow.cpp \
diff --git a/device.c b/device.c
index 2baa2e03a..6244e4117 100644
--- a/device.c
+++ b/device.c
@@ -2,119 +2,6 @@
 #include "dive.h"
 #include "device.h"
 
-static struct device_info *device_info_list;
-
-struct device_info *head_of_device_info_list(void)
-{
-	return device_info_list;
-}
-
-void remove_dive_computer(const char *model, uint32_t deviceid)
-{
-	free(remove_device_info(model, deviceid));
-}
-
-static int match_device_info(struct device_info *entry, const char *model, uint32_t deviceid)
-{
-	return !strcmp(entry->model, model) && entry->deviceid == deviceid;
-}
-
-/* just find the entry for this divecomputer */
-struct device_info *get_device_info(const char *model, uint32_t deviceid)
-{
-	struct device_info *known = device_info_list;
-
-	/* a 0 deviceid doesn't get a nickname - those come from development
-	 * versions of Subsurface that didn't store the deviceid in the divecomputer entries */
-	if (!deviceid || !model)
-		return NULL;
-	while (known) {
-		if (match_device_info(known, model, deviceid))
-			return known;
-		known = known->next;
-	}
-	return NULL;
-}
-
-/*
- * Sort the device_info list, so that we write it out
- * in a stable order. Otherwise we'll end up having the
- * XML file have the devices listed in some arbitrary
- * order, which is annoying.
- */
-static void add_entry_sorted(struct device_info *entry)
-{
-	struct device_info *p, **pp = &device_info_list;
-
-	while ((p = *pp) != NULL) {
-		int cmp = strcmp(p->model, entry->model);
-		if (cmp > 0)
-			break;
-		if (!cmp && p->deviceid > entry->deviceid)
-			break;
-		pp = &p->next;
-	}
-
-	entry->next = p;
-	*pp = entry;
-}
-
-/* Get an existing device info model or create a new one if valid */
-struct device_info *create_device_info(const char *model, uint32_t deviceid)
-{
-	struct device_info *entry;
-
-	if (!deviceid || !model || !*model)
-		return NULL;
-	entry = get_device_info(model, deviceid);
-	if (entry)
-		return entry;
-	entry = calloc(1, sizeof(*entry));
-	if (entry) {
-		entry->model = strdup(model);
-		entry->deviceid = deviceid;
-		add_entry_sorted(entry);
-	}
-	return entry;
-}
-
-/* do we have a DIFFERENT divecomputer of the same model? */
-struct device_info *get_different_device_info(const char *model, uint32_t deviceid)
-{
-	struct device_info *known = device_info_list;
-
-	/* a 0 deviceid matches any DC of the same model - those come from development
-	 * versions of Subsurface that didn't store the deviceid in the divecomputer entries */
-	if (!deviceid)
-		return NULL;
-	if (!model)
-		model = "";
-	while (known) {
-		if (known->model && !strcmp(known->model, model) &&
-		    known->deviceid != deviceid)
-			return known;
-		known = known->next;
-	}
-	return NULL;
-}
-
-struct device_info *remove_device_info(const char *model, uint32_t deviceid)
-{
-	struct device_info *entry, **p;
-
-	if (!deviceid || !model || !*model)
-		return NULL;
-	p = &device_info_list;
-	while ((entry = *p) != NULL) {
-		if (match_device_info(entry, model, deviceid)) {
-			*p = entry->next;
-			break;
-		}
-		p = &entry->next;
-	}
-	return entry;
-}
-
 struct divecomputer* fake_dc(struct divecomputer* dc)
 {
 	static struct sample fake[4];
diff --git a/device.h b/device.h
index 59969473a..3067f009e 100644
--- a/device.h
+++ b/device.h
@@ -6,23 +6,10 @@
 extern "C" {
 #endif
 
-struct device_info {
-	const char *model;
-	uint32_t deviceid;
-
-	const char *serial_nr;
-	const char *firmware;
-	const char *nickname;
-	struct device_info *next;
-};
-
-extern struct device_info *get_device_info(const char *model, uint32_t deviceid);
-extern struct device_info *get_different_device_info(const char *model, uint32_t deviceid);
-extern struct device_info *create_device_info(const char *model, uint32_t deviceid);
-extern struct device_info *remove_device_info(const char *model, uint32_t deviceid);
-extern struct device_info *head_of_device_info_list(void);
 extern struct divecomputer *fake_dc(struct divecomputer* dc);
-extern void remove_dive_computer(const char *model, uint32_t deviceid);
+extern void create_device_node(const char *model, uint32_t deviceid, const char *serial, const char *firmware, const char *nickname);
+extern void call_for_each_dc(FILE *f, void (*callback)(FILE *, const char *, uint32_t,
+						const char *, const char *, const char *));
 
 #ifdef __cplusplus
 }
diff --git a/dive.h b/dive.h
index 3a46eb2d4..39943d6c6 100644
--- a/dive.h
+++ b/dive.h
@@ -653,7 +653,6 @@ extern void dive_list_update_dives(void);
 extern void flush_divelist(struct dive *dive);
 
 extern void set_dc_nickname(struct dive *dive);
-extern const char *get_dc_nickname(const char *model, uint32_t deviceid);
 extern void set_autogroup(gboolean value);
 extern int total_weight(struct dive *);
 
diff --git a/divelist.c b/divelist.c
index 606c30e01..6e3fc598e 100644
--- a/divelist.c
+++ b/divelist.c
@@ -1059,7 +1059,7 @@ static void try_to_renumber(struct dive *last, int preexisting)
 
 void process_dives(bool is_imported, bool prefer_imported)
 {
-		int i;
+	int i;
 	int preexisting = dive_table.preexisting;
 	struct dive *last;
 
diff --git a/helpers.h b/helpers.h
index 57b5aa6f7..81fddbd5e 100644
--- a/helpers.h
+++ b/helpers.h
@@ -9,6 +9,7 @@
 
 #include <QString>
 #include "dive.h"
+#include "qthelper.h"
 
 QString get_depth_string(depth_t depth, bool showunit);
 QString get_weight_string(weight_t weight, bool showunit);
@@ -18,5 +19,8 @@ QString get_pressure_string(pressure_t pressure, bool showunit);
 void set_default_dive_computer(const char *vendor, const char *product);
 void set_default_dive_computer_device(const char *name);
 QString getSubsurfaceDataPath(QString folderToFind);
+extern const QString get_dc_nickname(const char *model, uint32_t deviceid);
+
+extern DiveComputerList dcList;
 
 #endif /* HELPER_H */
diff --git a/libdivecomputer.c b/libdivecomputer.c
index 6397018a3..2638376b8 100644
--- a/libdivecomputer.c
+++ b/libdivecomputer.c
@@ -578,36 +578,29 @@ static unsigned int undo_libdivecomputer_suunto_nr_changes(unsigned int serial)
 
 static unsigned int fixup_suunto_versions(device_data_t *devdata, const dc_event_devinfo_t *devinfo)
 {
-	struct device_info *info;
 	unsigned int serial = devinfo->serial;
+	char serial_nr[13] = "";
+	char firmware[13] = "";
 
 	first_temp_is_air = 1;
 
 	serial = undo_libdivecomputer_suunto_nr_changes(serial);
 
-	info = create_device_info(devdata->model, devdata->deviceid);
-	if (!info)
-		return serial;
-
-	if (!info->serial_nr && serial) {
-		char serial_nr[13];
-
+	if (serial) {
 		snprintf(serial_nr, sizeof(serial_nr), "%02d%02d%02d%02d",
 			(devinfo->serial >> 24) & 0xff,
 			(devinfo->serial >> 16) & 0xff,
 			(devinfo->serial >> 8)  & 0xff,
 			(devinfo->serial >> 0)  & 0xff);
-		info->serial_nr = strdup(serial_nr);
 	}
-
-	if (!info->firmware && devinfo->firmware) {
-		char firmware[13];
+	if (devinfo->firmware) {
 		snprintf(firmware, sizeof(firmware), "%d.%d.%d",
 			(devinfo->firmware >> 16) & 0xff,
 			(devinfo->firmware >> 8)  & 0xff,
 			(devinfo->firmware >> 0)  & 0xff);
-		info->firmware = strdup(firmware);
 	}
+	create_device_node(devdata->model, devdata->deviceid, serial_nr, firmware, "");
+
 	return serial;
 }
 
diff --git a/parse-xml.c b/parse-xml.c
index ba952957f..aa2f737ec 100644
--- a/parse-xml.c
+++ b/parse-xml.c
@@ -1222,17 +1222,8 @@ static void dc_settings_start(void)
 
 static void dc_settings_end(void)
 {
-	struct device_info *info;
-
-	info = create_device_info(cur_settings.dc.model, cur_settings.dc.deviceid);
-	if (info) {
-		if (!info->serial_nr && cur_settings.dc.serial_nr)
-			info->serial_nr = strdup(cur_settings.dc.serial_nr);
-		if (!info->firmware && cur_settings.dc.firmware)
-			info->firmware = strdup(cur_settings.dc.firmware);
-		if (!info->nickname && cur_settings.dc.nickname)
-			info->nickname = strdup(cur_settings.dc.nickname);
-	}
+	create_device_node(cur_settings.dc.model, cur_settings.dc.deviceid, cur_settings.dc.serial_nr,
+			   cur_settings.dc.firmware, cur_settings.dc.nickname);
 	reset_dc_settings();
 }
 
diff --git a/qt-gui.cpp b/qt-gui.cpp
index e15e4128e..10b7d8086 100644
--- a/qt-gui.cpp
+++ b/qt-gui.cpp
@@ -21,6 +21,7 @@
 #include "libdivecomputer.h"
 #include "qt-ui/mainwindow.h"
 #include "helpers.h"
+#include "qthelper.h"
 
 #include <QApplication>
 #include <QFileDialog>
@@ -32,10 +33,13 @@
 #include <QDesktopWidget>
 #include <QStyle>
 #include <QDebug>
+#include <QMap>
+#include <QMultiMap>
 
 const char *default_dive_computer_vendor;
 const char *default_dive_computer_product;
 const char *default_dive_computer_device;
+DiveComputerList dcList;
 
 class Translator: public QTranslator
 {
@@ -142,30 +146,15 @@ void set_filename(const char *filename, gboolean force)
 		existing_filename = NULL;
 }
 
-const char *get_dc_nickname(const char *model, uint32_t deviceid)
+const QString get_dc_nickname(const char *model, uint32_t deviceid)
 {
-	struct device_info *known = get_device_info(model, deviceid);
-	if (known) {
-		if (known->nickname && *known->nickname)
-			return known->nickname;
-		else
-			return known->model;
-	}
-	return NULL;
-}
-
-void remember_dc(const char *model, uint32_t deviceid, const char *nickname)
-{
-	struct device_info *nn_entry;
-
-	nn_entry = create_device_info(model, deviceid);
-	if (!nn_entry)
-		return;
-	if (!nickname || !*nickname) {
-		nn_entry->nickname = NULL;
-		return;
-	}
-	nn_entry->nickname = strdup(nickname);
+	const DiveComputerNode *existNode = dcList.getExact(model, deviceid);
+	if (!existNode)
+		return QString("");
+	if (existNode->nickName != "")
+		return existNode->nickName;
+	else
+		return model;
 }
 
 void set_dc_nickname(struct dive *dive)
@@ -176,16 +165,20 @@ void set_dc_nickname(struct dive *dive)
 	struct divecomputer *dc = &dive->dc;
 
 	while (dc) {
-		if (get_dc_nickname(dc->model, dc->deviceid) == NULL) {
+		if (dc->model && *dc->model && dc->deviceid &&
+		    !dcList.getExact(dc->model, dc->deviceid)) {
 			// we don't have this one, yet
-			struct device_info *nn_entry = get_different_device_info(dc->model, dc->deviceid);
-			if (nn_entry) {
+			const DiveComputerNode *existNode = dcList.get(dc->model);
+			if (existNode) {
 				// we already have this model but a different deviceid
 				QString simpleNick(dc->model);
-				simpleNick.append(" (").append(QString::number(dc->deviceid, 16)).append(")");
-				remember_dc(dc->model, dc->deviceid, simpleNick.toUtf8().data());
+				if (dc->deviceid == 0)
+					simpleNick.append(" (unknown deviceid)");
+				else
+					simpleNick.append(" (").append(QString::number(dc->deviceid, 16)).append(")");
+				dcList.addDC(dc->model, dc->deviceid, simpleNick);
 			} else {
-				remember_dc(dc->model, dc->deviceid, NULL);
+				dcList.addDC(dc->model, dc->deviceid);
 			}
 		}
 		dc = dc->next;
@@ -330,4 +323,20 @@ QString getSubsurfaceDataPath(QString folderToFind)
 	return QString("");
 }
 
+void create_device_node(const char *model, uint32_t deviceid, const char *serial, const char *firmware, const char *nickname)
+{
+	dcList.addDC(model, deviceid, nickname, serial, firmware);
+}
+
+void call_for_each_dc(FILE *f, void (*callback)(FILE *, const char *, uint32_t,
+						const char *, const char *, const char *))
+{
+	QList<DiveComputerNode> values = dcList.dcMap.values();
+	for (int i = 0; i < values.size(); i++) {
+		const DiveComputerNode *node = &values.at(i);
+		callback(f, node->model.toUtf8().data(), node->deviceId, node->nickName.toUtf8().data(),
+			 node->serialNumber.toUtf8().data(), node->firmware.toUtf8().data());
+	}
+}
+
 #include "qt-gui.moc"
diff --git a/qt-ui/divecomputermanagementdialog.cpp b/qt-ui/divecomputermanagementdialog.cpp
index 4d9770a4d..2a1bb8bff 100644
--- a/qt-ui/divecomputermanagementdialog.cpp
+++ b/qt-ui/divecomputermanagementdialog.cpp
@@ -3,16 +3,26 @@
 #include "ui_divecomputermanagementdialog.h"
 #include "mainwindow.h"
 #include <QMessageBox>
+#include "../qthelper.h"
+#include "../helpers.h"
 
-DiveComputerManagementDialog::DiveComputerManagementDialog(QWidget* parent, Qt::WindowFlags f): QDialog(parent, f)
-, ui( new Ui::DiveComputerManagementDialog())
+DiveComputerManagementDialog::DiveComputerManagementDialog(QWidget* parent, Qt::WindowFlags f): QDialog(parent, f),
+	ui( new Ui::DiveComputerManagementDialog()),
+	model(0)
 {
 	ui->setupUi(this);
-	model = new DiveComputerModel();
-	ui->tableView->setModel(model);
+	init();
 	connect(ui->tableView, SIGNAL(clicked(QModelIndex)), this, SLOT(tryRemove(QModelIndex)));
 }
 
+void DiveComputerManagementDialog::init()
+{
+	if (model)
+		delete model;
+	model = new DiveComputerModel(dcList.dcMap);
+	ui->tableView->setModel(model);
+}
+
 DiveComputerManagementDialog* DiveComputerManagementDialog::instance()
 {
 	static DiveComputerManagementDialog *self = new DiveComputerManagementDialog();
@@ -44,3 +54,17 @@ void DiveComputerManagementDialog::tryRemove(const QModelIndex& index)
 		model->remove(index);
 	}
 }
+
+void DiveComputerManagementDialog::accept()
+{
+	model->keepWorkingList();
+	hide();
+	close();
+}
+
+void DiveComputerManagementDialog::reject()
+{
+	model->dropWorkingList();
+	hide();
+	close();
+}
diff --git a/qt-ui/divecomputermanagementdialog.h b/qt-ui/divecomputermanagementdialog.h
index e10a96db2..72d48cd2a 100644
--- a/qt-ui/divecomputermanagementdialog.h
+++ b/qt-ui/divecomputermanagementdialog.h
@@ -14,9 +14,12 @@ Q_OBJECT
 public:
     static DiveComputerManagementDialog *instance();
 	void update();
+	void init();
 
 public  slots:
 	void tryRemove(const QModelIndex& index);
+	void accept();
+	void reject();
 
 private:
     explicit DiveComputerManagementDialog(QWidget* parent = 0, Qt::WindowFlags f = 0);
@@ -24,4 +27,4 @@ private:
 	DiveComputerModel *model;
 };
 
-#endif
\ No newline at end of file
+#endif
diff --git a/qt-ui/divecomputermanagementdialog.ui b/qt-ui/divecomputermanagementdialog.ui
index ae011fc9c..8b916f925 100644
--- a/qt-ui/divecomputermanagementdialog.ui
+++ b/qt-ui/divecomputermanagementdialog.ui
@@ -11,7 +11,7 @@
    </rect>
   </property>
   <property name="windowTitle">
-   <string>Dialog</string>
+   <string>Edit Dive Computer Nicknames</string>
   </property>
   <layout class="QVBoxLayout" name="verticalLayout">
    <item>
@@ -21,8 +21,51 @@
      </attribute>
     </widget>
    </item>
+   <item>
+    <widget class="QDialogButtonBox" name="buttonBox">
+     <property name="orientation">
+      <enum>Qt::Horizontal</enum>
+     </property>
+     <property name="standardButtons">
+      <set>QDialogButtonBox::Cancel|QDialogButtonBox::Ok</set>
+     </property>
+    </widget>
+   </item>
   </layout>
  </widget>
  <resources/>
- <connections/>
+ <connections>
+  <connection>
+   <sender>buttonBox</sender>
+   <signal>accepted()</signal>
+   <receiver>DiveComputerManagementDialog</receiver>
+   <slot>accept()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>248</x>
+     <y>254</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>157</x>
+     <y>274</y>
+    </hint>
+   </hints>
+  </connection>
+  <connection>
+   <sender>buttonBox</sender>
+   <signal>rejected()</signal>
+   <receiver>DiveComputerManagementDialog</receiver>
+   <slot>reject()</slot>
+   <hints>
+    <hint type="sourcelabel">
+     <x>316</x>
+     <y>260</y>
+    </hint>
+    <hint type="destinationlabel">
+     <x>286</x>
+     <y>274</y>
+    </hint>
+   </hints>
+  </connection>
+ </connections>
 </ui>
diff --git a/qt-ui/mainwindow.cpp b/qt-ui/mainwindow.cpp
index ca6fa4113..26f4d864d 100644
--- a/qt-ui/mainwindow.cpp
+++ b/qt-ui/mainwindow.cpp
@@ -207,6 +207,7 @@ void MainWindow::on_actionDownloadWeb_triggered()
 
 void MainWindow::on_actionEditDeviceNames_triggered()
 {
+	DiveComputerManagementDialog::instance()->init();
 	DiveComputerManagementDialog::instance()->update();
 	DiveComputerManagementDialog::instance()->show();
 }
diff --git a/qt-ui/models.cpp b/qt-ui/models.cpp
index 2de8ababa..485015379 100644
--- a/qt-ui/models.cpp
+++ b/qt-ui/models.cpp
@@ -8,8 +8,8 @@
 #include "../helpers.h"
 #include "../dive.h"
 #include "../device.h"
-#include  "../statistics.h"
-
+#include "../statistics.h"
+#include "../qthelper.h"
 
 #include <QCoreApplication>
 #include <QDebug>
@@ -1172,9 +1172,10 @@ void DiveTripModel::setLayout(DiveTripModel::Layout layout)
  *####################################################################
  */
 
-DiveComputerModel::DiveComputerModel(QObject* parent): QAbstractTableModel(parent)
+DiveComputerModel::DiveComputerModel(QMultiMap<QString, DiveComputerNode> &dcMap, QObject* parent): QAbstractTableModel(parent)
 {
-
+	dcWorkingMap = dcMap;
+	numRows = 0;
 }
 
 int DiveComputerModel::columnCount(const QModelIndex& parent) const
@@ -1198,17 +1199,15 @@ QVariant DiveComputerModel::headerData(int section, Qt::Orientation orientation,
 
 QVariant DiveComputerModel::data(const QModelIndex& index, int role) const
 {
-	struct device_info *device = head_of_device_info_list();
-	for(int i = 0; i < index.row(); i++){
-		device = device->next;
-	}
+	QList<DiveComputerNode> values = dcWorkingMap.values();
+	DiveComputerNode node = values.at(index.row());
 
 	QVariant ret;
 	if (role == Qt::DisplayRole || role == Qt::EditRole){
 		switch(index.column()){
-			case ID:	ret = QString("0x").append(QString::number(device->deviceid, 16)); break;
-			case MODEL:	ret = device->model; break;
-			case NICKNAME:	ret = device->nickname; break;
+			case ID:	ret = QString("0x").append(QString::number(node.deviceId, 16)); break;
+			case MODEL:	ret = node.model; break;
+			case NICKNAME:	ret = node.nickName; break;
 		}
 	}
 
@@ -1225,12 +1224,8 @@ int DiveComputerModel::rowCount(const QModelIndex& parent) const
 
 void DiveComputerModel::update()
 {
-	int count = 0;
-	struct device_info *nnl = head_of_device_info_list();
-	while (nnl) {
-		nnl = nnl->next;
-		count++;
-	}
+	QList<DiveComputerNode> values = dcWorkingMap.values();
+	int count = values.count();
 
 	if(numRows){
 		beginRemoveRows(QModelIndex(), 0, numRows-1);
@@ -1255,25 +1250,19 @@ Qt::ItemFlags DiveComputerModel::flags(const QModelIndex& index) const
 
 bool DiveComputerModel::setData(const QModelIndex& index, const QVariant& value, int role)
 {
-	struct device_info *nnl = head_of_device_info_list();
-
-	for(int i = 0; i < index.row(); i++){
-		nnl = nnl->next;
-	}
-
-
-	QByteArray v = value.toByteArray();
-	nnl->nickname = strdup(v.data()); // how should I free this before setting a new one?
-	// set_dc_nickname(dive);  -> should this be used instead?
-
+	QList<DiveComputerNode> values = dcWorkingMap.values();
+	DiveComputerNode node = values.at(index.row());
+	dcWorkingMap.remove(node.model, node);
+	node.nickName = value.toString();
+	dcWorkingMap.insert(node.model, node);
 	return true;
 }
 
-void DiveComputerModel::remove(const QModelIndex& i)
+void DiveComputerModel::remove(const QModelIndex& index)
 {
-	QByteArray model = data(index(i.row(), (int)MODEL)).toByteArray();
-	uint32_t deviceid = data(index(i.row(), (int) ID)).toUInt();
-	remove_dive_computer(model.data(),  deviceid);
+	QList<DiveComputerNode> values = dcWorkingMap.values();
+	DiveComputerNode node = values.at(index.row());
+	dcWorkingMap.remove(node.model, node);
 	update();
 }
 
@@ -1396,3 +1385,15 @@ void YearlyStatisticsModel::update_yearly_stats()
 		rootItem->children.append(item);
 	}
 }
+
+void DiveComputerModel::dropWorkingList()
+{
+	// how do I prevent the memory leak ?
+}
+
+void DiveComputerModel::keepWorkingList()
+{
+	if (dcList.dcMap != dcWorkingMap)
+		mark_divelist_changed(TRUE);
+	dcList.dcMap = dcWorkingMap;
+}
diff --git a/qt-ui/models.h b/qt-ui/models.h
index 30d4b3a17..35ed529e3 100644
--- a/qt-ui/models.h
+++ b/qt-ui/models.h
@@ -13,6 +13,7 @@
 
 #include "../dive.h"
 #include "../divelist.h"
+#include "../qthelper.h"
 
 QFont defaultModelFont();
 
@@ -181,19 +182,22 @@ class DiveComputerModel : public QAbstractTableModel
 	Q_OBJECT
 public:
 	enum {REMOVE, MODEL, ID, NICKNAME, COLUMNS};
-    explicit DiveComputerModel(QObject* parent = 0);
-    virtual QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const;
-    virtual int columnCount(const QModelIndex& parent = QModelIndex()) const;
-    virtual QVariant data(const QModelIndex& index, int role = Qt::DisplayRole) const;
-    virtual int rowCount(const QModelIndex& parent = QModelIndex()) const;
-    virtual Qt::ItemFlags flags(const QModelIndex& index) const;
-    virtual bool setData(const QModelIndex& index, const QVariant& value, int role = Qt::EditRole);
+	DiveComputerModel(QMultiMap<QString, DiveComputerNode> &dcMap, QObject *parent = 0);
+	virtual QVariant headerData(int section, Qt::Orientation orientation, int role = Qt::DisplayRole) const;
+	virtual int columnCount(const QModelIndex& parent = QModelIndex()) const;
+	virtual QVariant data(const QModelIndex& index, int role = Qt::DisplayRole) const;
+	virtual int rowCount(const QModelIndex& parent = QModelIndex()) const;
+	virtual Qt::ItemFlags flags(const QModelIndex& index) const;
+	virtual bool setData(const QModelIndex& index, const QVariant& value, int role = Qt::EditRole);
 	void update();
+	void keepWorkingList();
+	void dropWorkingList();
 
 public slots:
 	void remove(const QModelIndex& index);
 private:
 	int numRows;
+	QMultiMap<QString, DiveComputerNode> dcWorkingMap;
 };
 
 class YearlyStatisticsModel : public TreeModel {
diff --git a/qt-ui/profilegraphics.cpp b/qt-ui/profilegraphics.cpp
index 126690750..e580a2b44 100644
--- a/qt-ui/profilegraphics.cpp
+++ b/qt-ui/profilegraphics.cpp
@@ -21,6 +21,7 @@
 #include "../dive.h"
 #include "../profile.h"
 #include "../device.h"
+#include "../helpers.h"
 
 #include <libdivecomputer/parser.h>
 #include <libdivecomputer/version.h>
@@ -273,7 +274,7 @@ void ProfileGraphicsView::plot(struct dive *d, bool forceRedraw)
 		dc = fake_dc(dc);
 	}
 
-	QString nick(get_dc_nickname(dc->model, dc->deviceid));
+	QString nick = get_dc_nickname(dc->model, dc->deviceid);
 	if (nick.isEmpty())
 		nick = QString(dc->model);
 
diff --git a/qthelper.cpp b/qthelper.cpp
new file mode 100644
index 000000000..9c74a74cf
--- /dev/null
+++ b/qthelper.cpp
@@ -0,0 +1,82 @@
+#include "qthelper.h"
+
+DiveComputerList::DiveComputerList()
+{
+
+}
+
+DiveComputerList::~DiveComputerList()
+{
+	dcMap.~QMap();
+}
+
+bool DiveComputerNode::operator == (const DiveComputerNode &a) const {
+	return this->model == a.model &&
+			this->deviceId == a.deviceId &&
+			this->firmware == a.firmware &&
+			this->serialNumber == a.serialNumber &&
+			this->nickName == a.nickName;
+}
+
+bool DiveComputerNode::operator !=(const DiveComputerNode &a) const {
+	return !(*this == a);
+}
+
+bool DiveComputerNode::changesValues(const DiveComputerNode &b) const
+{
+	if (this->model != b.model || this->deviceId != b.deviceId) {
+		qDebug("DiveComputerNodes were not for the same DC");
+		return false;
+	}
+	return (b.firmware != "" && this->firmware != b.firmware) ||
+			(b.serialNumber != "" && this->serialNumber != b.serialNumber) ||
+			(b.nickName != "" && this->nickName != b.nickName);
+}
+
+const DiveComputerNode *DiveComputerList::getExact(QString m, uint32_t d)
+{
+	if (dcMap.contains(m)) {
+		QList<DiveComputerNode> values = dcMap.values(m);
+		for (int i = 0; i < values.size(); i++)
+			if (values.at(i).deviceId == d)
+				return &values.at(i);
+	}
+	return NULL;
+}
+
+const DiveComputerNode *DiveComputerList::get(QString m)
+{
+	if (dcMap.contains(m)) {
+		QList<DiveComputerNode> values = dcMap.values(m);
+		return &values.at(0);
+	}
+	return NULL;
+}
+
+void DiveComputerList::addDC(QString m, uint32_t d, QString n, QString s, QString f)
+{
+	if (m == "" || d == 0)
+		return;
+	const DiveComputerNode *existNode = this->getExact(m, d);
+	DiveComputerNode newNode(m, d, s, f, n);
+	if (existNode) {
+		if (newNode.changesValues(*existNode)) {
+			if (n != "" && existNode->nickName != n)
+				qDebug("new nickname %s for DC model %s deviceId 0x%x", n.toUtf8().data(), m.toUtf8().data(), d);
+			if (f != "" && existNode->firmware != f)
+				qDebug("new firmware version %s for DC model %s deviceId 0x%x", f.toUtf8().data(), m.toUtf8().data(), d);
+			if (s != "" && existNode->serialNumber != s)
+				qDebug("new serial number %s for DC model %s deviceId 0x%x", s.toUtf8().data(), m.toUtf8().data(), d);
+		} else {
+			return;
+		}
+		dcMap.remove(m, *existNode);
+	}
+	dcMap.insert(m, newNode);
+}
+
+void DiveComputerList::rmDC(QString m, uint32_t d)
+{
+	const DiveComputerNode *existNode = this->getExact(m, d);
+	dcMap.remove(m, *existNode);
+}
diff --git a/qthelper.h b/qthelper.h
new file mode 100644
index 000000000..fcbcbff9a
--- /dev/null
+++ b/qthelper.h
@@ -0,0 +1,35 @@
+#ifndef QTHELPER_H
+#define QTHELPER_H
+
+#include <QMultiMap>
+#include <QString>
+#include <stdint.h>
+
+class DiveComputerNode {
+public:
+	DiveComputerNode(QString m, uint32_t d, QString s, QString f, QString n) : model(m), deviceId(d), serialNumber(s), firmware(f), nickName(n) {};
+	bool operator ==(const DiveComputerNode &a) const;
+	bool operator !=(const DiveComputerNode &a) const;
+	bool changesValues(const DiveComputerNode &b) const;
+	QString model;
+	uint32_t deviceId;
+	QString serialNumber;
+	QString firmware;
+	QString nickName;
+};
+
+class DiveComputerList {
+public:
+	DiveComputerList();
+	~DiveComputerList();
+	const DiveComputerNode *getExact(QString m, uint32_t d);
+	const DiveComputerNode *get(QString m);
+	void addDC(QString m, uint32_t d, QString n = "", QString s = "", QString f = "");
+	void rmDC(QString m, uint32_t d);
+	DiveComputerNode matchDC(QString m, uint32_t d);
+	DiveComputerNode matchModel(QString m);
+	QMultiMap<QString, struct DiveComputerNode> dcMap;
+	QMultiMap<QString, struct DiveComputerNode> dcWorkingMap;
+};
+
+#endif // QTHELPER_H
diff --git a/save-xml.c b/save-xml.c
index 0e770ec62..454da8484 100644
--- a/save-xml.c
+++ b/save-xml.c
@@ -512,24 +512,20 @@ static void save_trip(FILE *f, dive_trip_t *trip)
 	fprintf(f, "</trip>\n");
 }
 
-static void save_one_device(FILE *f, struct device_info *info)
+static void save_one_device(FILE *f, const char * model, uint32_t deviceid,
+			    const char *nickname, const char *serial_nr, const char *firmware)
 {
-	const char *nickname, *serial_nr, *firmware;
-
 	/* Nicknames that are empty or the same as the device model are not interesting */
-	nickname = info->nickname;
 	if (nickname) {
-		if (!*nickname || !strcmp(info->model, nickname))
+		if (!*nickname || !strcmp(model, nickname))
 			nickname = NULL;
 	}
 
 	/* Serial numbers that are empty are not interesting */
-	serial_nr = info->serial_nr;
 	if (serial_nr && !*serial_nr)
 		serial_nr = NULL;
 
 	/* Firmware strings that are empty are not interesting */
-	firmware = info->firmware;
 	if (firmware && !*firmware)
 		firmware = NULL;
 
@@ -538,25 +534,14 @@ static void save_one_device(FILE *f, struct device_info *info)
 		return;
 
 	fprintf(f, "<divecomputerid");
-	show_utf8(f, info->model, " model='", "'", 1);
-	fprintf(f, " deviceid='%08x'", info->deviceid);
+	show_utf8(f, model, " model='", "'", 1);
+	fprintf(f, " deviceid='%08x'", deviceid);
 	show_utf8(f, serial_nr, " serial='", "'", 1);
 	show_utf8(f, firmware, " firmware='", "'", 1);
 	show_utf8(f, nickname, " nickname='", "'", 1);
 	fprintf(f, "/>\n");
 }
 
-static void save_device_info(FILE *f)
-{
-	struct device_info *info;
-
-	info = head_of_device_info_list();
-	while (info) {
-		save_one_device(f, info);
-		info = info->next;
-	}
-}
-
 #define VERSION 2
 
 void save_dives(const char *filename)
@@ -578,7 +563,7 @@ void save_dives_logic(const char *filename, const gboolean select_only)
 	fprintf(f, "<divelog program='subsurface' version='%d'>\n<settings>\n", VERSION);
 
 	/* save the dive computer nicknames, if any */
-	save_device_info(f);
+	call_for_each_dc(f, save_one_device);
 	if (autogroup)
 		fprintf(f, "<autogroup state='1' />\n");
 	fprintf(f, "</settings>\n<dives>\n");