tracker/trackhat: simplify connection state tracking

1 files changed, 72 insertions, 0 deletions

diff --git a/tracker-trackhat/handle.cpp b/tracker-trackhat/handle.cpp
new file mode 100644
index 00000000..0c2ce822
--- /dev/null
+++ b/tracker-trackhat/handle.cpp
@@ -0,0 +1,72 @@
+#undef NDEBUG
+#include "trackhat.hpp"
+#include "compat/sleep.hpp"
+#include "compat/timer.hpp"
+#include <cassert>
+
+bool camera_handle::ensure_connected()
+{
+    if (state_ >= st_streaming)
+        return true;
+    else if (state_ == st_stopped)
+        return false;
+
+    Timer t;
+
+    constexpr int max_attempts = 5;
+
+    if (!ensure_device_exists())
+        goto error;
+
+    for (int i = 0; i < max_attempts; i++)
+    {
+        if (!th_check(trackHat_Connect(&device_, TH_FRAME_EXTENDED)))
+        {
+            state_ = st_streaming;
+            if (int ms = (int)t.elapsed_ms(); ms > 1000)
+                qDebug() << "tracker/trackhat: connecting took" << ms << "ms";
+            return true;
+        }
+
+        auto dbg = qDebug();
+        dbg << "tracker/trackhat: connect failed, retry";
+        dbg.space(); dbg.nospace();
+        dbg << i << "/" << max_attempts;
+        portable::sleep(50);
+    }
+
+error:
+    disconnect();
+    return false;
+}
+
+bool camera_handle::ensure_device_exists()
+{
+    switch (state_)
+    {
+    case st_streaming:
+        return true;
+    case st_detected:
+        disconnect();
+        [[fallthrough]];
+    case st_stopped:
+        assert(!th_check(trackHat_Initialize(&device_)) && device_.m_pInternal);
+        if (auto error = th_check(trackHat_DetectDevice(&device_)); error)
+        {
+            disconnect();
+            return false;
+        }
+        state_ = st_detected;
+        return true;
+    }
+}
+
+void camera_handle::disconnect()
+{
+    state_ = st_stopped;
+    if (device_.m_pInternal)
+    {
+        (void)!th_check(trackHat_Disconnect(&device_));
+        trackHat_Deinitialize(&device_);
+    }
+}