implement gain dialog with AGC option

owrx/form/device.py

@@ -0,0 +1,33 @@
+from owrx.form import Input
+
+
+class GainInput(Input):
+    def render_input(self, value):
+        auto_mode = value is None or value == "auto"
+
+        return """
+            <div id="{id}">
+                <select class="{classes}" id="{id}-select" name="{id}-select">
+                    <option value="auto" {auto_selected}>Enable hardware AGC</option>
+                    <option value="manual" {manual_selected}>Specify manual gain</option>
+                </select>
+                <div class="option manual" style="display: none;">
+                    <input type="number" id="{id}-manual" name="{id}-manual" value="{value}" class="{classes}" placeholder="Manual device gain" value="{value}" step="any">
+                </div>
+            </div>
+        """.format(
+            id=self.id,
+            classes=self.input_classes(),
+            value=value,
+            label=self.label,
+            auto_selected="selected" if auto_mode else "",
+            manual_selected="" if auto_mode else "selected",
+        )
+
+    def parse(self, data):
+        select_id = "{id}-select".format(id=self.id)
+        if select_id in data:
+            input_id = "{id}-manual".format(id=self.id)
+            if data[select_id][0] == "manual" and input_id in data:
+                return {self.id: float(data[input_id][0])}
+        return {self.id: None}