Implement Seac SeacSync databaser parser.

Dives for the seac action computer are imported by the seacsync
program into two tables in an sqlite3 database.

The dive information is read from the headers_dive table.
The dive_data table is then queried for each dive to get samples.

The seac action computer is the only current supported computer
by the seacsync program. It only supports two gas mixes, so the
parser will toggle between two cylinders whenever it detects a
change in the active O2 mix.

Dive start time is stored in UTC with a timezone offset.
A helper function to read this was added to qthelper.

Default cases have been added to some switch statements
to assist in future development for other dive types and
salinity.

Example database has been added to ./dives/TestDiveSeacSync.db

Signed-off-by: James Wobser <james.wobser@gmail.com>

11 files changed, 345 insertions, 1 deletions

diff --git a/CHANGELOG.md b/CHANGELOG.md
index e92bb5e60..1b63acb77 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -11,6 +11,7 @@ core: correctly recognize A1 as BLE dive computer
 planner: Honor the "O2 narcotic" preference when computing MND
 desktop: fix broken merging of dives with multiple cylinders
 mobile: add information about the cloud sync state to the Subsurface plate in the menu
+core: Add parser for SeacSync db. Currently only Seac Action uses SeacSync program.
 
 ---
 * Always add new entries at the very top of this file above other existing entries and this note.
diff --git a/Documentation/user-manual.txt b/Documentation/user-manual.txt
index 30693cd52..e741d5507 100644
--- a/Documentation/user-manual.txt
+++ b/Documentation/user-manual.txt
@@ -1197,6 +1197,7 @@ available, as in dialog *B*, above. Currently these are:
  - OSTC Tools logs
  - JDiveLog
  - Suunto Dive Manager (DM3, DM4, DM5)
+ - Seac SeacSync
  - DL7 files used by Diver's Alert network (DAN)
  - Underwater technologies AV1 dive logs
  - Divesoft dive logs
@@ -1373,6 +1374,20 @@ _Subsurface_ *Dive List* panel.
 
 image::images/Divelogs1.jpg["FIGURE:Download from Divelogs.de",align="center"]
 
+[[S_ImportingSeacSync]]
+==== Importing dives from SeacSync
+
+_Subsurface_ can directly import the database generated by the proprietary SeacSync
+application. Simply locate the database file on your computer, then use the
+<<Unified_import, universal import dialog.>>
+
+On Windows 10, The SeacSync database is typically found in:
+    C:\[USERNAME]\AppData\Roaming\SeacSync\divesDB.db
+
+_Subsurface_ will not modify the database during import, so it can be imported directly from this
+location.
+
+
 [[S_ImportingCSVData]]
 ==== Importing data in CSV format
 
diff --git a/core/CMakeLists.txt b/core/CMakeLists.txt
index 4a498cde8..fedba3614 100644
--- a/core/CMakeLists.txt
+++ b/core/CMakeLists.txt
@@ -110,6 +110,7 @@ set(SUBSURFACE_CORE_LIB_SRCS
 	import-divinglog.c
 	import-shearwater.c
 	import-suunto.c
+	import-seac.c
 	libdivecomputer.c
 	libdivecomputer.h
 	liquivision.c
diff --git a/core/file.c b/core/file.c
index ed00b7948..619ec5724 100644
--- a/core/file.c
+++ b/core/file.c
@@ -136,6 +136,7 @@ static int try_to_open_db(const char *filename, struct memblock *mem, struct div
 	char shearwater_cloud_test[] = "select count(*) from sqlite_master where type='table' and name='SyncV3MetadataDiveLog' and sql like '%CreatedDevice%'";
 	char cobalt_test[] = "select count(*) from sqlite_master where type='table' and name='TrackPoints' and sql like '%DepthPressure%'";
 	char divinglog_test[] = "select count(*) from sqlite_master where type='table' and name='DBInfo' and sql like '%PrgName%'";
+	char seacsync_test[] = "select count(*) from sqlite_master where type='table' and name='dive_data' and sql like '%ndl_tts_s%'";
 	int retval;
 
 	retval = sqlite3_open(filename, &handle);
@@ -193,6 +194,15 @@ static int try_to_open_db(const char *filename, struct memblock *mem, struct div
 		return retval;
 	}
 
+	/* Testing if DB schema resembles Seac database format */
+	retval = sqlite3_exec(handle, seacsync_test, &db_test_func, 0, NULL);
+	if (!retval) {
+		retval = parse_seac_buffer(handle, filename, mem->buffer, mem->size, table, trips, sites);
+		sqlite3_close(handle);
+		return retval;
+	}
+
+
 	sqlite3_close(handle);
 
 	return retval;
diff --git a/core/import-seac.c b/core/import-seac.c
new file mode 100644
index 000000000..4b34cbe99
--- /dev/null
+++ b/core/import-seac.c
@@ -0,0 +1,303 @@
+// SPDX-License-Identifier: GPL-2.0
+#ifdef __clang__
+// Clang has a bug on zero-initialization of C structs.
+#pragma clang diagnostic ignored "-Wmissing-field-initializers"
+#endif
+
+#include "qthelper.h"
+#include "ssrf.h"
+#include "dive.h"
+#include "subsurface-string.h"
+#include "subsurface-time.h"
+#include "parse.h"
+#include "divelist.h"
+#include "device.h"
+#include "membuffer.h"
+#include "gettext.h"
+#include "tag.h"
+#include "errorhelper.h"
+#include <string.h>
+
+/* Process gas change event for seac database.
+ * Create gas change event at the time of the
+ * current sample.
+ */
+static int seac_gaschange(void *param, sqlite3_stmt *sqlstmt)
+{
+	struct parser_state *state = (struct parser_state *)param;
+
+	event_start(state);
+	state->cur_event.time.seconds = sqlite3_column_int(sqlstmt, 1);
+	strcpy(state->cur_event.name, "gaschange");
+	state->cur_event.gas.mix.o2.permille = 10 * sqlite3_column_int(sqlstmt, 4);
+	event_end(state);
+
+	return 0;
+}
+
+/* Callback function to parse seac dives. Reads headers_dive table to read dive
+ * information into divecomputer struct.
+ */
+static int seac_dive(void *param, int columns, char **data, char **column)
+{
+	UNUSED(columns);
+	UNUSED(column);
+	int retval = 0, cylnum = 0;
+	int year, month, day, hour, min, sec, tz;
+	char isodatetime[30];
+	time_t divetime;
+	struct gasmix lastgas, curgas;
+	struct parser_state *state = (struct parser_state *)param;
+	sqlite3 *handle = state->sql_handle;
+	sqlite3_stmt *sqlstmt;
+
+	const char *get_samples = "SELECT dive_number, runtime_s, depth_cm, temperature_mCx10, active_O2_fr, first_stop_depth_cm, first_stop_time_s, ndl_tts_s, cns, gf_l, gf_h FROM dive_data WHERE dive_number = ? ORDER BY runtime_s ASC";
+		/*  0 = dive_number
+		 *  1 = runtime_s
+		 *  2 = depth_cm
+		 *  3 = temperature_mCx10  - eg dC
+		 *  4 = active_O2_fr
+		 *  5 = first_stop_depth_cm
+		 *  6 = first_stop_time_s
+		 *  7 = ndl_tts_s
+		 *  8 = cns
+		 *  9 = gf-l
+		 * 10 = gf-h
+		 */
+
+	dive_start(state);
+	state->cur_dive->number = atoi(data[0]);
+
+	// Create first cylinder
+	cylinder_t *curcyl = get_or_create_cylinder(state->cur_dive, 0);
+
+	// Get time and date
+	sscanf(data[2], "%d/%d/%2d", &day, &month, &year);
+	sscanf(data[4], "%2d:%2d:%2d", &hour, &min, &sec);
+	year += 2000;
+
+	tz = atoi(data[3]);
+	// Timezone offset lookup array
+	const char timezoneoffset[][7] =
+	{"+12:00",  //  0
+	 "+11:00",  //  1
+	 "+10:00",  //  2
+	 "+09:30",  //  3
+	 "+09:00",  //  4
+	 "+08:00",  //  5
+	 "+07:00",  //  6
+	 "+06:00",  //  7
+	 "+05:00",  //  8
+	 "+04:30",  //  9
+	 "+04:00",  // 10
+	 "+03:30",  // 11
+	 "+03:00",  // 12
+	 "+02:00",  // 13
+	 "+01:00",  // 14
+	 "+00:00",  // 15
+	 "-01:00",  // 16
+	 "-02:00",  // 17
+	 "-03:00",  // 18
+	 "-03:30",  // 19
+	 "-04:00",  // 20
+	 "-04:30",  // 21
+	 "-05:00",  // 22
+	 "-05:30",  // 23
+	 "-05:45",  // 24
+	 "-06:00",  // 25
+	 "-06:30",  // 26
+	 "-07:00",  // 27
+	 "-08:00",  // 28
+	 "-08:45",  // 29
+	 "-09:00",  // 30
+	 "-09:30",  // 31
+	 "-09:45",  // 32
+	 "-10:00",  // 33
+	 "-10:30",  // 34
+	 "-11:00",  // 35
+	 "-11:30",  // 36
+	 "-12:00",  // 37
+	 "-12:45",  // 38
+	 "-13:00",  // 39
+	 "-13:45",  // 40
+	 "-14:00"}; // 41
+
+	sprintf(isodatetime, "%4i-%02i-%02iT%02i:%02i:%02i%6s", year, month, day, hour, min, sec, timezoneoffset[tz]);
+	divetime = get_dive_datetime_from_isostring(isodatetime);
+	state->cur_dive->when = divetime;
+
+	// 6 = dive_type
+	// Dive type 2?
+	if (data[6]) {
+		switch (atoi(data[6])) {
+		case 1:
+			state->cur_dive->dc.divemode = OC;
+			break;
+		// Gauge Mode
+		case 2:
+			state->cur_dive->dc.divemode = UNDEF_COMP_TYPE;
+			break;
+		case 3:
+			state->cur_dive->dc.divemode = FREEDIVE;
+			break;
+		default:
+			if (verbose) {
+				fprintf(stderr, "Unknown divetype %i", atoi(data[6]));
+			}
+		}
+	}
+
+	// 9 = comments from seac app
+	if (data[9]) {
+		utf8_string(data[9], &state->cur_dive->notes);
+	}
+
+	// 10 = dive duration
+	if (data[10]) {
+		state->cur_dive->dc.duration.seconds = atoi(data[10]);
+	}
+
+	// 8 = water_type
+	/* TODO: Seac only offers fresh / salt, and doesn't
+	 * seem to record correctly currently. I have both
+	 * fresh and saltwater dives and water type is reported
+	 * as 150 for both.
+	 */
+	if (data[8]) {
+		switch (atoi(data[8])) {
+		case 150:
+			state->cur_dive->salinity = 0;
+			break;
+		case 100:
+			state->cur_dive->salinity = 1;
+			break;
+		default:
+			if (verbose) {
+				fprintf(stderr, "Unknown salinity %i", atoi(data[8]));
+			}
+		}
+	}
+
+
+	if (data[11]) {
+		state->cur_dive->dc.maxdepth.mm = 10 * atoi(data[11]);
+	}
+
+	// Create sql_stmt type to query DB
+	retval = sqlite3_prepare_v2(handle, get_samples, -1, &sqlstmt, 0);
+	if (retval != SQLITE_OK) {
+		fprintf(stderr, "%s", "Preparing SQL object failed when getting SeacSync dives.\n");
+		return 1;
+	}
+
+	// Bind current dive number to sql statement
+	sqlite3_bind_int(sqlstmt, 1, state->cur_dive->number);
+
+	// Catch a bad query
+	retval = sqlite3_step(sqlstmt);
+	if (retval == SQLITE_ERROR) {
+		fprintf(stderr, "%s", "Getting dive data from SeacSync DB failed.\n");
+		return 1;
+	}
+
+	settings_start(state);
+	dc_settings_start(state);
+
+	utf8_string(data[1], &state->cur_dive->dc.serial);
+	utf8_string(data[12], &state->cur_dive->dc.fw_version);
+	state->cur_dive->dc.model = strdup("Seac Action");
+	// TODO: Calculate device hash from string
+	state->cur_dive->dc.deviceid = 0xffffffff;
+	add_extra_data(&state->cur_dive->dc, "GF-Lo", (const char*)sqlite3_column_text(sqlstmt, 9));
+	add_extra_data(&state->cur_dive->dc, "GF-Hi", (const char*)sqlite3_column_text(sqlstmt, 10));
+
+	dc_settings_end(state);
+	settings_end(state);
+
+	if (data[11]) {
+		state->cur_dive->dc.maxdepth.mm = 10 * atoi(data[11]);
+	}
+
+	curcyl->gasmix.o2.permille = 10 * sqlite3_column_int(sqlstmt, 4);
+
+
+	// Track gasses to tell when switch occurs
+	lastgas = curcyl->gasmix;
+	curgas = curcyl->gasmix;
+
+	// Read samples
+	while (retval == SQLITE_ROW) {
+		sample_start(state);
+		state->cur_sample->time.seconds = sqlite3_column_int(sqlstmt, 1);
+		state->cur_sample->depth.mm = 10 * sqlite3_column_int(sqlstmt, 2);
+		state->cur_sample->temperature.mkelvin = cC_to_mkelvin(sqlite3_column_int(sqlstmt, 3));
+		curgas.o2.permille = 10 * sqlite3_column_int(sqlstmt, 4);
+		if (!same_gasmix(lastgas, curgas)) {
+			seac_gaschange(state, sqlstmt);
+			lastgas = curgas;
+			cylnum ^= 1; // Only need to toggle between two cylinders
+			curcyl = get_or_create_cylinder(state->cur_dive, cylnum);
+			curcyl->gasmix.o2.permille = 10 * sqlite3_column_int(sqlstmt, 4);
+		}
+		state->cur_sample->stopdepth.mm = 10 * sqlite3_column_int(sqlstmt, 5);
+		state->cur_sample->stoptime.seconds = sqlite3_column_int(sqlstmt, 6);
+		state->cur_sample->ndl.seconds = sqlite3_column_int(sqlstmt, 7);
+		state->cur_sample->cns = sqlite3_column_int(sqlstmt, 8);
+		sample_end(state);
+		retval = sqlite3_step(sqlstmt);
+	}
+
+	sqlite3_finalize(sqlstmt);
+	dive_end(state);
+
+	return SQLITE_OK;
+}
+
+/** Read SeacSync divesDB.db sqlite3 database into dive and samples.
+ *
+ * Each row returned in the query of headers_dive creates a new dive.
+ * The callback function performs another SQL query on the other
+ * table, to read in the sample values.
+ */
+int parse_seac_buffer(sqlite3 *handle, const char *url, const char *buffer, int size,
+		     struct dive_table *table, struct trip_table *trips, struct dive_site_table *sites)
+{
+	UNUSED(buffer);
+	UNUSED(size);
+
+	int retval;
+	char *err = NULL;
+	struct parser_state state;
+
+	init_parser_state(&state);
+	state.target_table = table;
+	state.trips = trips;
+	state.sites = sites;
+	state.sql_handle = handle;
+
+	const char *get_dives = "SELECT dive_number, device_sn, date, timezone, time, elapsed_surface_time, dive_type, start_mode, water_type, comment, total_dive_time, max_depth, firmware_version FROM headers_dive";
+		/*  0 = dive_number
+		 *  1 = device_sn
+		 *  2 = date
+		 *  3 = timezone
+		 *  4 = time
+		 *  5 = elapsed_surface_time
+		 *  6 = dive_type
+		 *  7 = start_mode
+		 *  8 = water_type
+		 *  9 = comment
+		 * 10 = total_dive_time
+		 * 11 = max_depth
+		 * 12 = firmware version
+		 */
+
+	retval = sqlite3_exec(handle, get_dives, &seac_dive, &state, &err);
+	free_parser_state(&state);
+
+	if (retval != SQLITE_OK) {
+		fprintf(stderr, "Database query failed '%s'.\n", url);
+		return 1;
+	}
+
+	return 0;
+}
\ No newline at end of file
diff --git a/core/parse.h b/core/parse.h
index 8886bcd8d..350b98ed8 100644
--- a/core/parse.h
+++ b/core/parse.h
@@ -121,6 +121,7 @@ int atoi_n(char *ptr, unsigned int len);
 
 int parse_dm4_buffer(sqlite3 *handle, const char *url, const char *buf, int size, struct dive_table *table, struct trip_table *trips, struct dive_site_table *sites);
 int parse_dm5_buffer(sqlite3 *handle, const char *url, const char *buf, int size, struct dive_table *table, struct trip_table *trips, struct dive_site_table *sites);
+int parse_seac_buffer(sqlite3 *handle, const char *url, const char *buf, int size, struct dive_table *table, struct trip_table *trips, struct dive_site_table *sites);
 int parse_shearwater_buffer(sqlite3 *handle, const char *url, const char *buf, int size, struct dive_table *table, struct trip_table *trips, struct dive_site_table *sites);
 int parse_shearwater_cloud_buffer(sqlite3 *handle, const char *url, const char *buf, int size, struct dive_table *table, struct trip_table *trips, struct dive_site_table *sites);
 int parse_cobalt_buffer(sqlite3 *handle, const char *url, const char *buf, int size, struct dive_table *table, struct trip_table *trips, struct dive_site_table *sites);
diff --git a/core/qthelper.cpp b/core/qthelper.cpp
index 0de3e6002..203234f05 100644
--- a/core/qthelper.cpp
+++ b/core/qthelper.cpp
@@ -5,7 +5,6 @@
 #include "core/settings/qPrefUpdateManager.h"
 #include "core/subsurface-qt/divelistnotifier.h"
 #include "subsurface-string.h"
-#include "subsurface-string.h"
 #include "gettextfromc.h"
 #include "statistics.h"
 #include "membuffer.h"
@@ -955,6 +954,12 @@ QString get_dive_date_string(timestamp_t when)
 	return loc.toString(ts.toUTC(), QString(prefs.date_format) + " " + prefs.time_format);
 }
 
+// Get local seconds since Epoch from ISO formatted UTC date time + offset string
+extern "C" time_t get_dive_datetime_from_isostring(char *when) {
+	QDateTime divetime = QDateTime::fromString(when, Qt::ISODate);
+	return (time_t)(divetime.toSecsSinceEpoch());
+}
+
 QString get_short_dive_date_string(timestamp_t when)
 {
 	QDateTime ts;
diff --git a/core/qthelper.h b/core/qthelper.h
index a18d6d04d..a3394e684 100644
--- a/core/qthelper.h
+++ b/core/qthelper.h
@@ -5,6 +5,7 @@
 #include <libxslt/transform.h>
 #include <libxslt/xsltutils.h>
 #include "core/pref.h"
+#include "subsurface-time.h"
 
 struct picture;
 
@@ -147,6 +148,7 @@ const char *subsurface_user_agent();
 enum deco_mode decoMode();
 int parse_seabear_header(const char *filename, char **params, int pnr);
 char *get_current_date();
+time_t get_dive_datetime_from_isostring(char *when);
 void print_qt_versions();
 void lock_planner();
 void unlock_planner();
diff --git a/core/units.h b/core/units.h
index 1b042513b..0ce97e21c 100644
--- a/core/units.h
+++ b/core/units.h
@@ -230,6 +230,11 @@ static inline unsigned long C_to_mkelvin(double c)
 	return lrint(c * 1000 + ZERO_C_IN_MKELVIN);
 }
 
+static inline unsigned long cC_to_mkelvin(double c)
+{
+	return lrint(c * 10 + ZERO_C_IN_MKELVIN);
+}
+
 static inline double psi_to_bar(double psi)
 {
 	return psi / 14.5037738;
diff --git a/dives/TestDiveSeacSync.db b/dives/TestDiveSeacSync.db
new file mode 100644
index 000000000..a0a68246a
--- /dev/null
+++ b/dives/TestDiveSeacSync.db
diff --git a/packaging/ios/Subsurface-mobile.pro b/packaging/ios/Subsurface-mobile.pro
index 36da3e3af..1281d0377 100644
--- a/packaging/ios/Subsurface-mobile.pro
+++ b/packaging/ios/Subsurface-mobile.pro
@@ -67,6 +67,7 @@ SOURCES += ../../subsurface-mobile-main.cpp \
 	../../core/pictureobj.cpp \
 	../../core/import-suunto.c \
 	../../core/import-shearwater.c \
+	../../core/import-seac.c \
 	../../core/import-cobalt.c \
 	../../core/import-divinglog.c \
 	../../core/import-csv.c \