From d72f43190b62ea5e789b5db4216c8eed0ff4f5b9 Mon Sep 17 00:00:00 2001
From: ShouvikGhosh2048 <shouvikg.cal@gmail.com>
Date: Wed, 16 Feb 2022 21:41:26 +0000
Subject: [PATCH] Fixes #1452 - Prevents empty trades

---
 common/src/trade.rs      |  4 +++-
 server/src/sys/agent.rs  |  2 +-
 voxygen/src/hud/trade.rs | 19 +++++++++++++++++--
 3 files changed, 21 insertions(+), 4 deletions(-)

diff --git a/common/src/trade.rs b/common/src/trade.rs
index 4d8bd721a6..f37ac12ef7 100644
--- a/common/src/trade.rs
+++ b/common/src/trade.rs
@@ -116,6 +116,8 @@ impl PendingTrade {
             .map(|(i, _)| i)
     }
 
+    pub fn is_empty_trade(&self) -> bool { self.offers[0].is_empty() && self.offers[1].is_empty() }
+
     /// Invariants:
     /// - A party is never shown as offering more of an item than they own
     /// - Offers with a quantity of zero get removed from the trade
@@ -165,7 +167,7 @@ impl PendingTrade {
                 }
             },
             Accept(phase) => {
-                if self.phase == phase {
+                if self.phase == phase && !self.is_empty_trade() {
                     self.accept_flags[who] = true;
                 }
                 if self.accept_flags[0] && self.accept_flags[1] {
diff --git a/server/src/sys/agent.rs b/server/src/sys/agent.rs
index ba3b3431d7..d21cd5ca58 100644
--- a/server/src/sys/agent.rs
+++ b/server/src/sys/agent.rs
@@ -1226,7 +1226,7 @@ impl<'a> AgentData<'a> {
                         // results in lagging and moving to the review phase of an unfavorable trade
                         // (although since the phase is included in the message, this shouldn't
                         // result in fully accepting an unfavourable trade))
-                        if !pending.accept_flags[who] {
+                        if !pending.accept_flags[who] && !pending.is_empty_trade() {
                             event_emitter.emit(ServerEvent::ProcessTradeAction(
                                 *self.entity,
                                 tradeid,
diff --git a/voxygen/src/hud/trade.rs b/voxygen/src/hud/trade.rs
index d1cfd454f1..36f428d4e7 100644
--- a/voxygen/src/hud/trade.rs
+++ b/voxygen/src/hud/trade.rs
@@ -473,10 +473,25 @@ impl<'a> Trade<'a> {
         trade: &'a PendingTrade,
     ) -> <Self as Widget>::Event {
         let mut event = None;
+        let (hover_img, press_img, accept_button_luminance) = if trade.is_empty_trade() {
+            //Darken the accept button if the trade is empty.
+            (
+                self.imgs.button,
+                self.imgs.button,
+                Color::Rgba(0.6, 0.6, 0.6, 1.0),
+            )
+        } else {
+            (
+                self.imgs.button_hover,
+                self.imgs.button_press,
+                Color::Rgba(1.0, 1.0, 1.0, 1.0),
+            )
+        };
         if Button::image(self.imgs.button)
             .w_h(31.0 * 5.0, 12.0 * 2.0)
-            .hover_image(self.imgs.button_hover)
-            .press_image(self.imgs.button_press)
+            .hover_image(hover_img)
+            .press_image(press_img)
+            .image_color(accept_button_luminance)
             .bottom_left_with_margins_on(state.ids.bg, 90.0, 47.0)
             .label(self.localized_strings.get("hud.trade.accept"))
             .label_font_size(self.fonts.cyri.scale(14))