From 214272468df34bf88f6ae8fef8338dfab46e160f Mon Sep 17 00:00:00 2001
From: Benau <Benau@users.noreply.github.com>
Date: Sat, 5 Jan 2019 00:42:00 +0800
Subject: [PATCH] Add left or right player action to change spectating target

---
 src/input/input_manager.cpp            | 23 +++++++++++++++++++++++
 src/network/protocols/client_lobby.cpp | 14 +++++++++++---
 2 files changed, 34 insertions(+), 3 deletions(-)

diff --git a/src/input/input_manager.cpp b/src/input/input_manager.cpp
index d26c2db2c..42cdd4f36 100644
--- a/src/input/input_manager.cpp
+++ b/src/input/input_manager.cpp
@@ -38,6 +38,7 @@
 #include "modes/profile_world.hpp"
 #include "modes/world.hpp"
 #include "network/network_config.hpp"
+#include "network/protocols/client_lobby.hpp"
 #include "network/rewind_manager.hpp"
 #include "physics/physics.hpp"
 #include "race/history.hpp"
@@ -806,6 +807,28 @@ void InputManager::dispatchInput(Input::InputType type, int deviceID,
 
             if (pk == NULL)
             {
+                if (auto cl = LobbyProtocol::get<ClientLobby>())
+                {
+                    Camera* cam = Camera::getActiveCamera();
+                    if (cl->isSpectator() && cam)
+                    {
+                        // Network spectating handling
+                        int current_idx = 0;
+                        if (cam->getKart())
+                            current_idx = cam->getKart()->getWorldKartId();
+                        if (action == PA_STEER_LEFT && value == 0)
+                            current_idx = ++current_idx % World::getWorld()->getNumKarts();
+                        else if (action == PA_STEER_RIGHT && value == 0)
+                        {
+                            if (current_idx == 0)
+                                current_idx = World::getWorld()->getNumKarts() - 1;
+                            else
+                                current_idx = --current_idx;
+                        }
+                        cam->setKart(World::getWorld()->getKart(current_idx));
+                        return;
+                    }
+                }
                 Log::error("InputManager::dispatchInput", "Trying to process "
                     "action for an unknown player");
                 return;
diff --git a/src/network/protocols/client_lobby.cpp b/src/network/protocols/client_lobby.cpp
index 9e2121990..dcc947e20 100644
--- a/src/network/protocols/client_lobby.cpp
+++ b/src/network/protocols/client_lobby.cpp
@@ -21,6 +21,7 @@
 #include "audio/sfx_manager.hpp"
 #include "config/user_config.hpp"
 #include "config/player_manager.hpp"
+#include "graphics/camera.hpp"
 #include "guiengine/modaldialog.hpp"
 #include "guiengine/message_queue.hpp"
 #include "guiengine/screen_keyboard.hpp"
@@ -280,14 +281,21 @@ void ClientLobby::addAllPlayers(Event* event)
     // Disable until render gui during loading is bug free
     //StateManager::get()->enterGameState();
 
-    // Live join if state is CONNECTED
+    // Live join or spectate if state is CONNECTED
     if (m_state.load() == CONNECTED)
     {
         World* w = World::getWorld();
         w->setLiveJoinWorld(true);
+        Camera* cam = Camera::getActiveCamera();
         for (unsigned i = 0; i < w->getNumKarts(); i++)
         {
             AbstractKart* k = w->getKart(i);
+            // Change spectating target to first non-eliminated kart
+            if (isSpectator() && cam && !k->isEliminated())
+            {
+                cam->setKart(k);
+                cam = NULL;
+            }
             // The final joining ticks will be set by server later
             if (k->getController()->isLocalPlayerController())
                 k->setLiveJoinKart(std::numeric_limits<int>::max());
@@ -960,7 +968,7 @@ void ClientLobby::backToLobby(Event *event)
     {
     case BLR_NO_GAME_FOR_LIVE_JOIN:
         // I18N: Error message shown if live join failed in network
-        msg = _("No more game is available for live join.");
+        msg = _("No more game is available for live join or spectating.");
         break;
     case BLR_NO_PLACE_FOR_LIVE_JOIN:
         // I18N: Error message shown if live join failed in network
@@ -988,7 +996,7 @@ void ClientLobby::backToLobby(Event *event)
 void ClientLobby::finishedLoadingWorld()
 {
     NetworkString* ns = getNetworkString(1);
-    // Live join if state is CONNECTED
+    // Live join or spectate if state is CONNECTED
     ns->setSynchronous(m_state.load() == CONNECTED);
     ns->addUInt8(LE_CLIENT_LOADED_WORLD);
     sendToServer(ns, true);