fix(linux,windows): pass raw datetime components instead of epoch in dive converters

The Pigeon API was updated to accept individual datetime fields (year, month,
day, hour, minute, second, timezone_offset) but the Linux and Windows
native converters were still passing a single epoch value, causing build
failures due to argument count mismatches.

Author: ericgriffin

packages/libdivecomputer_plugin/linux/dive_converter.c

@@ -1,10 +1,10 @@
 #include "dive_converter.h"
 
+#include <limits.h>
 #include <math.h>
 #include <stdint.h>
 #include <stdio.h>
 #include <string.h>
-#include <time.h>
 
 const char* map_event_type(unsigned int type) {
     switch (type) {
@@ -47,16 +47,18 @@ LibdivecomputerPluginParsedDive* convert_parsed_dive(
         snprintf(hex + i * 2, 3, "%02x", dive->fingerprint[i]);
     }
 
-    // Convert datetime to epoch seconds (UTC).
-    struct tm t = {0};
-    t.tm_year = dive->year - 1900;
-    t.tm_mon = dive->month - 1;
-    t.tm_mday = dive->day;
-    t.tm_hour = dive->hour;
-    t.tm_min = dive->minute;
-    t.tm_sec = dive->second;
-    t.tm_isdst = 0;
-    int64_t epoch = (int64_t)timegm(&t);
+    // Pass raw datetime components (wall-clock-as-UTC).
+    int64_t dt_year = (int64_t)dive->year;
+    int64_t dt_month = (int64_t)dive->month;
+    int64_t dt_day = (int64_t)dive->day;
+    int64_t dt_hour = (int64_t)dive->hour;
+    int64_t dt_minute = (int64_t)dive->minute;
+    int64_t dt_second = (int64_t)dive->second;
+
+    // INT32_MIN means "timezone not reported" per libdivecomputer convention.
+    int64_t tz_val = (int64_t)dive->timezone;
+    int64_t* tz_offset =
+        (dive->timezone == INT32_MIN) ? NULL : &tz_val;
 
     // Convert samples (all 14 fields, sentinels -> NULL).
     FlValue* samples = fl_value_new_list();
@@ -232,7 +234,8 @@ LibdivecomputerPluginParsedDive* convert_parsed_dive(
 
     LibdivecomputerPluginParsedDive* result =
         libdivecomputer_plugin_parsed_dive_new(
-            hex, epoch, dive->max_depth, dive->avg_depth,
+            hex, dt_year, dt_month, dt_day, dt_hour, dt_minute, dt_second,
+            tz_offset, dive->max_depth, dive->avg_depth,
             (int64_t)dive->duration, min_temp, max_temp, samples, tanks,
             gas_mixes, events, dive_mode, deco_algorithm, gf_low, gf_high,
             conservatism);

packages/libdivecomputer_plugin/windows/dive_converter.cc

@@ -1,11 +1,10 @@
 #include "dive_converter.h"
 
+#include <climits>
 #include <cmath>
 #include <cstdint>
 #include <cstdio>
 #include <cstring>
-#include <ctime>
-#include <limits>
 #include <optional>
 #include <string>
 #include <vector>
@@ -50,16 +49,19 @@ ParsedDive ConvertParsedDive(const libdc_parsed_dive_t& dive) {
         snprintf(hex + i * 2, 3, "%02x", dive.fingerprint[i]);
     }
 
-    // Convert datetime to epoch seconds (UTC).
-    struct tm t = {};
-    t.tm_year = dive.year - 1900;
-    t.tm_mon = dive.month - 1;
-    t.tm_mday = dive.day;
-    t.tm_hour = dive.hour;
-    t.tm_min = dive.minute;
-    t.tm_sec = dive.second;
-    t.tm_isdst = 0;
-    int64_t epoch = static_cast<int64_t>(_mkgmtime(&t));
+    // Pass raw datetime components (wall-clock-as-UTC).
+    int64_t dt_year = static_cast<int64_t>(dive.year);
+    int64_t dt_month = static_cast<int64_t>(dive.month);
+    int64_t dt_day = static_cast<int64_t>(dive.day);
+    int64_t dt_hour = static_cast<int64_t>(dive.hour);
+    int64_t dt_minute = static_cast<int64_t>(dive.minute);
+    int64_t dt_second = static_cast<int64_t>(dive.second);
+
+    // INT32_MIN means "timezone not reported" per libdivecomputer convention.
+    std::optional<int64_t> tz_offset =
+        (dive.timezone == INT32_MIN)
+            ? std::nullopt
+            : std::optional<int64_t>(static_cast<int64_t>(dive.timezone));
 
     // Convert samples (all 14 fields, sentinels -> nullptr).
     flutter::EncodableList samples;
@@ -238,7 +240,13 @@ ParsedDive ConvertParsedDive(const libdc_parsed_dive_t& dive) {
 
     return ParsedDive(
         std::string(hex),
-        epoch,
+        dt_year,
+        dt_month,
+        dt_day,
+        dt_hour,
+        dt_minute,
+        dt_second,
+        tz_offset ? &*tz_offset : nullptr,
         dive.max_depth,
         dive.avg_depth,
         static_cast<int64_t>(dive.duration),