Add test cases for direction flip.

Closes #1051.

test_apps/main/test_relay_chn.c

@@ -647,6 +647,91 @@ TEST_CASE("Tilt functionality is disabled, skipping tilt tests", "[relay_chn][ti
 #endif // CONFIG_RELAY_CHN_ENABLE_TILTING
 
 
+// ### Direction Flipping Tests
+
+TEST_CASE("Single channel direction can be flipped", "[relay_chn][direction]")
+{
+    TEST_ESP_OK(relay_chn_create(gpio_map, gpio_count));
+    g_is_component_initialized = true;
+    const uint8_t ch = 0;
+
+    // 1. Initial direction should be default
+    TEST_ASSERT_EQUAL(RELAY_CHN_DIRECTION_DEFAULT, relay_chn_get_direction(ch));
+
+    // 2. Flip the direction
+    relay_chn_flip_direction(ch);
+    vTaskDelay(pdMS_TO_TICKS(opposite_inertia_ms + test_delay_margin_ms)); // Wait for flip inertia
+
+    // 3. Verify direction is flipped
+    TEST_ASSERT_EQUAL(RELAY_CHN_DIRECTION_FLIPPED, relay_chn_get_direction(ch));
+
+    // 4. Flip back
+    relay_chn_flip_direction(ch);
+    vTaskDelay(pdMS_TO_TICKS(opposite_inertia_ms + test_delay_margin_ms)); // Wait for flip inertia
+
+    // 5. Verify direction is back to default
+    TEST_ASSERT_EQUAL(RELAY_CHN_DIRECTION_DEFAULT, relay_chn_get_direction(ch));
+}
+
+TEST_CASE("All channels direction can be flipped simultaneously", "[relay_chn][direction]")
+{
+    TEST_ESP_OK(relay_chn_create(gpio_map, gpio_count));
+    g_is_component_initialized = true;
+
+    // 1. Flip all channels
+    relay_chn_flip_direction(RELAY_CHN_ID_ALL);
+    vTaskDelay(pdMS_TO_TICKS(opposite_inertia_ms + test_delay_margin_ms));
+
+    // 2. Verify all channels are flipped
+    for (uint8_t i = 0; i < relay_chn_count; i++) {
+        TEST_ASSERT_EQUAL(RELAY_CHN_DIRECTION_FLIPPED, relay_chn_get_direction(i));
+    }
+
+    // 3. Flip all back
+    relay_chn_flip_direction(RELAY_CHN_ID_ALL);
+    vTaskDelay(pdMS_TO_TICKS(opposite_inertia_ms + test_delay_margin_ms));
+
+    // 4. Verify all channels are back to default
+    for (uint8_t i = 0; i < relay_chn_count; i++) {
+        TEST_ASSERT_EQUAL(RELAY_CHN_DIRECTION_DEFAULT, relay_chn_get_direction(i));
+    }
+}
+
+TEST_CASE("Flipping a running channel stops it and flips direction", "[relay_chn][direction]")
+{
+    TEST_ESP_OK(relay_chn_create(gpio_map, gpio_count));
+    g_is_component_initialized = true;
+    const uint8_t ch = 0;
+
+    // 1. Start channel running and verify state
+    relay_chn_run_forward(ch);
+    vTaskDelay(pdMS_TO_TICKS(test_delay_margin_ms));
+    TEST_ASSERT_EQUAL(RELAY_CHN_STATE_FORWARD, relay_chn_get_state(ch));
+
+    // 2. Flip the direction while running
+    relay_chn_flip_direction(ch);
+    vTaskDelay(pdMS_TO_TICKS(test_delay_margin_ms)); // Give time for events to process
+    
+    // 3. The channel should stop as part of the flip process
+    TEST_ASSERT_EQUAL(RELAY_CHN_STATE_STOPPED, relay_chn_get_state(ch));
+
+    // 4. Wait for the flip inertia to pass, after which it should be FREE and FLIPPED
+    vTaskDelay(pdMS_TO_TICKS(opposite_inertia_ms + test_delay_margin_ms));
+    TEST_ASSERT_EQUAL(RELAY_CHN_STATE_FREE, relay_chn_get_state(ch));
+    TEST_ASSERT_EQUAL(RELAY_CHN_DIRECTION_FLIPPED, relay_chn_get_direction(ch));
+}
+
+TEST_CASE("Direction flip handles invalid channel ID gracefully", "[relay_chn][direction]")
+{
+    TEST_ESP_OK(relay_chn_create(gpio_map, gpio_count));
+    g_is_component_initialized = true;
+    const uint8_t invalid_ch = relay_chn_count + 5;
+
+    relay_chn_flip_direction(invalid_ch); // Call with an invalid ID
+    TEST_ASSERT_EQUAL(RELAY_CHN_DIRECTION_DEFAULT, relay_chn_get_direction(invalid_ch));
+}
+
+
 // ### `app_main` Function
 
 // --- app_main function ---