Parse GPS text in C++ and re-implement GPS changed check

This is SO MUCH easier then the convoluted and fragile C / glib code it
replaces.

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

1 files changed, 56 insertions, 3 deletions

diff --git a/qthelper.cpp b/qthelper.cpp
index 36d1d02c7..0af4dacea 100644
--- a/qthelper.cpp
+++ b/qthelper.cpp
@@ -1,4 +1,6 @@
 #include "qthelper.h"
+#include <QRegExp>
+#include <QDebug>
 
 DiveComputerList::DiveComputerList()
 {
@@ -83,14 +85,65 @@ QString weight_string(int weight_in_grams)
 	if (get_units()->weight == units::KG) {
 		int gr = weight_in_grams % 1000;
 		int kg = weight_in_grams / 1000;
-        if (kg >= 20.0) {
+	if (kg >= 20.0) {
 		  str = QString("0");
-        } else {
+	} else {
 		  str = QString("%1.%2").arg(kg).arg((unsigned)(gr) / 100);
-        }
+	}
 	} else {
 		double lbs = grams_to_lbs(weight_in_grams);
 		str = QString("%1").arg(lbs, 0, 'f', lbs >= 40.0 ? 0 : 1 );
 	}
 	return (str);
 }
+
+bool parseGpsText(const QString& gps_text, double *latitude, double *longitude)
+{
+	/* an empty string is interpreted as 0.0,0.0 and therefore "no gps location" */
+	if (gps_text.trimmed() == "") {
+		*latitude = 0.0;
+		*longitude = 0.0;
+		return true;
+	}
+	QRegExp r("\\s*([SN])\\s*(\\d+)[" UTF8_DEGREE "\\s]+(\\d+)\\.(\\d+)[^EW]*([EW])\\s*(\\d+)[" UTF8_DEGREE "\\s]+(\\d+)\\.(\\d+)");
+	if (r.indexIn(gps_text) != 8) {
+		// qDebug() << "Hemisphere" << r.cap(1) << "deg" << r.cap(2) << "min" << r.cap(3) << "decimal" << r.cap(4);
+		// qDebug() << "Hemisphere" << r.cap(5) << "deg" << r.cap(6) << "min" << r.cap(7) << "decimal" << r.cap(8);
+		*latitude = r.cap(2).toInt() + (r.cap(3) + QString(".") + r.cap(4)).toDouble() / 60.0;
+		*longitude = r.cap(6).toInt() + (r.cap(7) + QString(".") + r.cap(8)).toDouble() / 60.0;
+		if (r.cap(1) == "S")
+			*latitude *= -1.0;
+		if (r.cap(5) == "W")
+			*longitude *= -1.0;
+		// qDebug("%s -> %8.5f / %8.5f", gps_text.toLocal8Bit().data(), *latitude, *longitude);
+		return true;
+	}
+	return false;
+}
+
+bool gpsHasChanged(struct dive *dive, struct dive *master, const QString& gps_text)
+{
+	double latitude, longitude;
+	int latudeg, longudeg;
+
+	/* if we have a master and the dive's gps address is different from it,
+	 * don't change the dive */
+	if (master && (master->latitude.udeg != dive->latitude.udeg ||
+		       master->longitude.udeg != dive->longitude.udeg))
+		return false;
+
+	if (!parseGpsText(gps_text, &latitude, &longitude))
+		return false;
+
+	latudeg = rint(1000000 * latitude);
+	longudeg = rint(1000000 * longitude);
+
+	/* if dive gps didn't change, nothing changed */
+	if (dive->latitude.udeg == latudeg && dive->longitude.udeg == longudeg)
+		return false;
+	/* ok, update the dive and mark things changed */
+	dive->latitude.udeg = latudeg;
+	dive->longitude.udeg = longudeg;
+	return true;
+
+}