Track Android call capture and playback clocks

tools/chatgui-android/app/src/test/java/com/utun/chat/data/CallAudioTimingTest.kt

@@ -0,0 +1,47 @@
+package com.utun.chat.data
+
+import org.junit.Assert.*
+import org.junit.Test
+
+class CallAudioTimingTest {
+    @Test fun captureFallbackUsesSamplesInsteadOfReadCompletionJitter() {
+        val c = CallCaptureClock()
+        assertEquals(980_000L, c.firstSampleUs(0, 960, 1_000_000, null, null))
+        assertEquals(1_000_000L, c.firstSampleUs(960, 960, 1_035_000, null, null))
+        assertFalse(c.measured)
+        assertEquals(1_030_000L, c.firstSampleUs(1920, 960, 1_050_000, 2400, 1_040_000))
+        assertTrue(c.measured)
+        assertEquals(1_050_000L, c.firstSampleUs(2880, 960, 1_080_000, null, null))
+        c.reset()
+        assertFalse(c.measured)
+        assertEquals(1_980_000L, c.firstSampleUs(0, 960, 2_000_000, null, null))
+    }
+
+    @Test fun invalidCaptureTimestampDoesNotReplaceAnchor() {
+        val c = CallCaptureClock()
+        assertEquals(980_000L, c.firstSampleUs(0, 960, 1_000_000, -1, 1_000_000))
+        assertEquals(1_000_000L, c.firstSampleUs(960, 960, 1_020_000, 960, 2_000_000))
+        assertFalse(c.measured)
+    }
+
+    @Test fun headMeasuresPlayedSamplesAndUnwrapsUnsignedCounter() {
+        val h = CallPlaybackHead()
+        assertEquals(0L, h.update(0, 960))
+        assertEquals(240L, h.update(240, 960))
+        assertEquals(240L, h.update(240, 1920))
+        assertEquals(0x70000000L, h.update(0x70000000, 0x70000000L))
+        assertEquals(0xe0000000L, h.update(0xe0000000.toInt(), 0xe0000000L))
+        assertEquals(0x100000080L, h.update(128, 0x100000080L))
+        assertFalse(h.failed)
+    }
+
+    @Test fun resetAndImpossibleHeadFailClosedUntilNewDevice() {
+        val h = CallPlaybackHead()
+        assertEquals(480L, h.update(480, 960))
+        assertNull(h.update(0, 960))
+        assertTrue(h.failed)
+        assertNull(h.update(960, 960))
+        assertNull(CallPlaybackHead().update(1000, 960))
+        assertEquals(0L, CallPlaybackHead().update(0, 0))
+    }
+}