1 files changed, 88 insertions, 1 deletions
diff --git a/core/picture.c b/core/picture.c
index 36953b8b1..9440cef35 100644
--- a/core/picture.c
+++ b/core/picture.c
@@ -1,7 +1,9 @@
 // SPDX-License-Identifier: GPL-2.0
 #include "picture.h"
-#include "table.h"
+#include "dive.h"
+#include "metadata.h"
 #include "subsurface-string.h"
+#include "table.h"
 #include <stdlib.h>
 #include <string.h>
 
@@ -66,3 +68,88 @@ int get_picture_idx(const struct picture_table *t, const char *filename)
 	}
 	return -1;
 }
+
+/* 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;
+}
+
+/* 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 res;
+}
+
+// only add pictures that have timestamps between 30 minutes before the dive and
+// 30 minutes after the dive ends
+#define D30MIN (30 * 60)
+static bool dive_check_picture_time(const struct dive *d, timestamp_t timestamp)
+{
+	return time_from_dive(d, timestamp) < D30MIN;
+}
+
+/* Creates a picture and indicates the dive to which this picture should be added.
+ * The caller is responsible for actually adding the picture to the dive.
+ * If no appropriate dive was found, no picture is created and NULL is returned.
+ */
+struct picture *create_picture(const char *filename, int shift_time, bool match_all, struct dive **dive)
+{
+	struct metadata metadata;
+	timestamp_t timestamp;
+
+	get_metadata(filename, &metadata);
+	timestamp = metadata.timestamp + shift_time;
+	*dive = nearest_selected_dive(timestamp);
+
+	if (!*dive)
+		return NULL;
+	if (get_picture_idx(&(*dive)->pictures, filename) >= 0)
+		return NULL;
+	if (!match_all && !dive_check_picture_time(*dive, timestamp))
+		return NULL;
+
+	struct picture *picture = malloc(sizeof(struct picture));
+	picture->filename = strdup(filename);
+	picture->offset.seconds = metadata.timestamp - (*dive)->when + shift_time;
+	picture->location = metadata.location;
+	return picture;
+}
+
+bool picture_check_valid_time(timestamp_t timestamp, int shift_time)
+{
+	int i;
+	struct dive *dive;
+
+	for_each_dive (i, dive)
+		if (dive->selected && dive_check_picture_time(dive, timestamp + shift_time))
+			return true;
+	return false;
+}