Dive media: add media to closest dive

Currently, when selecting "Load media files even if time does not
match the dive time", the media are added to *all* selected dives.
Instead add it to the closest dive.

This seems like the less surprising behavior. Of course now if the
user really wants to add a media file to multiple dives, they will
have to do it manually.

To avoid a messy interface, this is solved by moving the iterate-
over-selected-dives loop to the core. Thus, a helper-function can
be made local to its translation unit.

Signed-off-by: Berthold Stoeger <bstoeger@mail.tuwien.ac.at>

4 files changed, 57 insertions, 24 deletions

diff --git a/core/dive.c b/core/dive.c
index 47143aaa3..f37b42a0b 100644
--- a/core/dive.c
+++ b/core/dive.c
@@ -4004,20 +4004,51 @@ static bool new_picture_for_dive(struct dive *d, const char *filename)
 	return true;
 }
 
+/* Return distance of timestamp to time of dive. Result is always positive, 0 means during dive. */
+static timestamp_t time_from_dive(const struct dive *d, timestamp_t timestamp)
+{
+	timestamp_t end_time = dive_endtime(d);
+	if (timestamp < d->when)
+		return d->when - timestamp;
+	else if (timestamp > end_time)
+		return timestamp - end_time;
+	else
+		return 0;
+}
+
 // only add pictures that have timestamps between 30 minutes before the dive and
 // 30 minutes after the dive ends
 #define D30MIN (30 * 60)
-bool dive_check_picture_time(const struct dive *d, int shift_time, timestamp_t timestamp)
+static bool dive_check_picture_time(const struct dive *d, timestamp_t timestamp)
 {
-	offset_t offset;
-	if (timestamp) {
-		offset.seconds = timestamp - d->when + shift_time;
-		if (offset.seconds > -D30MIN && offset.seconds < dive_totaltime(d) + D30MIN) {
-			// this picture belongs to this dive
-			return true;
+	return time_from_dive(d, timestamp) < D30MIN;
+}
+
+/* Return dive closest selected dive to given timestamp or NULL if no dives are selected. */
+static struct dive *nearest_selected_dive(timestamp_t timestamp)
+{
+	struct dive *d, *res = NULL;
+	int i;
+	timestamp_t offset, min = 0;
+
+	for_each_dive(i, d) {
+		if (!d->selected)
+			continue;
+		offset = time_from_dive(d, timestamp);
+		if (!res || offset < min) {
+			res = d;
+			min = offset;
 		}
+
+		/* We suppose that dives are sorted chronologically. Thus
+		 * if the offset starts to increase, we can end. This ignores
+		 * pathological cases such as overlapping dives. In such a
+		 * case the user will have to add pictures manually.
+		 */
+		if (offset == 0 || offset > min)
+			break;
 	}
-	return false;
+	return res;
 }
 
 bool picture_check_valid_time(timestamp_t timestamp, int shift_time)
@@ -4026,18 +4057,26 @@ bool picture_check_valid_time(timestamp_t timestamp, int shift_time)
 	struct dive *dive;
 
 	for_each_dive (i, dive)
-		if (dive->selected && dive_check_picture_time(dive, shift_time, timestamp))
+		if (dive->selected && dive_check_picture_time(dive, timestamp + shift_time))
 			return true;
 	return false;
 }
 
-void dive_create_picture(struct dive *dive, const char *filename, int shift_time, bool match_all)
+void create_picture(const char *filename, int shift_time, bool match_all)
 {
 	struct metadata metadata;
+	struct dive *dive;
+	timestamp_t timestamp;
+
 	get_metadata(filename, &metadata);
+	timestamp = metadata.timestamp + shift_time;
+	dive = nearest_selected_dive(timestamp);
+
+	if (!dive)
+		return;
 	if (!new_picture_for_dive(dive, filename))
 		return;
-	if (!match_all && !dive_check_picture_time(dive, shift_time, metadata.timestamp))
+	if (!match_all && !dive_check_picture_time(dive, timestamp))
 		return;
 
 	struct picture *picture = alloc_picture();
diff --git a/core/dive.h b/core/dive.h
index 92bb1bb33..19c39214f 100644
--- a/core/dive.h
+++ b/core/dive.h
@@ -376,8 +376,7 @@ struct picture {
 
 extern struct picture *alloc_picture();
 extern void free_picture(struct picture *picture);
-extern bool dive_check_picture_time(const struct dive *d, int shift_time, timestamp_t timestamp);
-extern void dive_create_picture(struct dive *d, const char *filename, int shift_time, bool match_all);
+extern void create_picture(const char *filename, int shift_time, bool match_all);
 extern void dive_add_picture(struct dive *d, struct picture *newpic);
 extern bool dive_remove_picture(struct dive *d, const char *filename);
 extern unsigned int dive_get_picture_count(struct dive *d);
diff --git a/desktop-widgets/divelistview.cpp b/desktop-widgets/divelistview.cpp
index 804bf9b9b..9a9330473 100644
--- a/desktop-widgets/divelistview.cpp
+++ b/desktop-widgets/divelistview.cpp
@@ -969,15 +969,8 @@ void DiveListView::matchImagesToDives(QStringList fileNames)
 		return;
 	updateLastImageTimeOffset(shiftDialog.amount());
 
-	Q_FOREACH (const QString &fileName, fileNames) {
-		int j = 0;
-		struct dive *dive;
-		for_each_dive (j, dive) {
-			if (!dive->selected)
-				continue;
-			dive_create_picture(dive, qPrintable(fileName), shiftDialog.amount(), shiftDialog.matchAll());
-		}
-	}
+	for (const QString &fileName: fileNames)
+		create_picture(qPrintable(fileName), shiftDialog.amount(), shiftDialog.matchAll());
 
 	mark_divelist_changed(true);
 	copy_dive(current_dive, &displayed_dive);
diff --git a/tests/testpicture.cpp b/tests/testpicture.cpp
index 695c965b0..a84925c72 100644
--- a/tests/testpicture.cpp
+++ b/tests/testpicture.cpp
@@ -25,13 +25,15 @@ void TestPicture::addPicture()
 
 	QCOMPARE(parse_file(SUBSURFACE_TEST_DATA "/dives/test44.xml", &dive_table), 0);
 	dive = get_dive(0);
+	// Pictures will be added to selected dives
+	dive->selected = true;
 	QVERIFY(dive != NULL);
 	pic1 = dive->picture_list;
 	// So far no picture in dive
 	QVERIFY(pic1 == NULL);
 
-	dive_create_picture(dive, SUBSURFACE_TEST_DATA "/dives/images/wreck.jpg", 0, false);
-	dive_create_picture(dive, SUBSURFACE_TEST_DATA "/dives/images/data_after_EOI.jpg", 0, false);
+	create_picture(SUBSURFACE_TEST_DATA "/dives/images/wreck.jpg", 0, false);
+	create_picture(SUBSURFACE_TEST_DATA "/dives/images/data_after_EOI.jpg", 0, false);
 	pic1 = dive->picture_list;
 	pic2 = pic1->next;
 	// Now there are two picture2