feat(protocol): negotiate display and native input

tools/test_generated_contracts.py

@@ -103,6 +103,44 @@ do {
     )
     fatalError("invalid allocation bounds were accepted")
 } catch { }
+let displayMode = try DisplayMode(resolutionWidth: 2560, resolutionHeight: 1440, fps: 120)
+for invalid in [
+    { try DisplayMode(resolutionWidth: 319, resolutionHeight: 1440, fps: 120) },
+    { try DisplayMode(resolutionWidth: 2560, resolutionHeight: 199, fps: 120) },
+    { try DisplayMode(resolutionWidth: 2560, resolutionHeight: 1440, fps: 241) },
+] {
+    do {
+        _ = try invalid()
+        fatalError("invalid display mode was accepted")
+    } catch { }
+}
+let allocationPolicy = try AllocationPolicy(
+    minimumKbps: 1000, targetKbps: 2000, maximumKbps: 3000, tier: "standard",
+    audience: "versevdi-gateway", protocolValue: "verse", protocolVersion: 1,
+    grantTtlSeconds: 60, reservationLeaseSeconds: 300
+)
+let legacyDisplayRequest = try SessionRequest(
+    clientDeviceId: "device-1", deviceKeyId: "key-1", poolId: "pool-1",
+    idempotencyKey: "request-1", policySnapshot: allocationPolicy,
+    requestedDisplayMode: nil
+).encodeJSON()
+guard !String(data: legacyDisplayRequest, encoding: .utf8)!.contains("requested_display_mode") else {
+    fatalError("legacy request encoded an absent display mode")
+}
+let displayRequest = try SessionRequest(
+    clientDeviceId: "device-1", deviceKeyId: "key-1", poolId: "pool-1",
+    idempotencyKey: "request-1", policySnapshot: allocationPolicy,
+    requestedDisplayMode: displayMode
+)
+guard try SessionRequest.decodeJSON(displayRequest.encodeJSON()).requestedDisplayMode == displayMode else {
+    fatalError("display mode did not round-trip")
+}
+var nullDisplayRequest = try JSONSerialization.jsonObject(with: displayRequest.encodeJSON()) as! [String: Any]
+nullDisplayRequest["requested_display_mode"] = NSNull()
+do {
+    _ = try SessionRequest.decodeJSON(try JSONSerialization.data(withJSONObject: nullDisplayRequest))
+    fatalError("explicit null display mode was accepted")
+} catch { }
 let streamPolicy = try ProviderStreamPolicy(
     resolutionWidth: 2560, resolutionHeight: 1440, fps: 120,
     codec: "HEVC", bitrateKbps: 40000, audioEnabled: true
@@ -218,6 +256,24 @@ fn main() {
     assert!(AllocationPolicy::new(
         100, 50, 25, "standard".into(), "audience".into(), "verse".into(), 1, 60, 300,
     ).is_err());
+    let display_mode = DisplayMode::new(2560, 1440, 120).unwrap();
+    assert!(DisplayMode::new(319, 1440, 120).is_err());
+    assert!(DisplayMode::new(2560, 199, 120).is_err());
+    assert!(DisplayMode::new(2560, 1440, 241).is_err());
+    let allocation_policy = AllocationPolicy::new(
+        1000, 2000, 3000, "standard".into(), "versevdi-gateway".into(),
+        "verse".into(), 1, 60, 300,
+    ).unwrap();
+    let legacy_display_request = SessionRequest::new(
+        "device-1".into(), "key-1".into(), "pool-1".into(), "request-1".into(),
+        allocation_policy.clone(), None,
+    ).unwrap();
+    assert!(legacy_display_request.requestedDisplayMode().is_none());
+    let display_request = SessionRequest::new(
+        "device-1".into(), "key-1".into(), "pool-1".into(), "request-1".into(),
+        allocation_policy, Some(display_mode.clone()),
+    ).unwrap();
+    assert_eq!(display_request.requestedDisplayMode(), &Some(display_mode));
     assert!(ProviderStreamPolicy::new(
         2560, 1440, 120, "HEVC".into(), 40000, true,
     ).is_ok());