Support CSI2031 (dark/light theme switching) + remove STDIN cache to avoid stale color queries (#5105)

* initial phase 1 implementation

* various fies

* some fixes

* fix fragmented stdin cases

* some fixes

* renaming

* guard against old clients

* implement csi 2031

* allow toggling theme with actions

* rustfmt

* fix: finalize trailing characters in ansi parser as well

* add pr

4 files changed, 83 insertions, 5 deletions

diff --git a/zellij-utils/src/plugin_api/action.proto b/zellij-utils/src/plugin_api/action.proto
index ea043d56..28a8337e 100644
--- a/zellij-utils/src/plugin_api/action.proto
+++ b/zellij-utils/src/plugin_api/action.proto
@@ -490,6 +490,9 @@ enum ActionName {
     ShowFloatingPanes = 98;
     HideFloatingPanes = 99;
     AreFloatingPanesVisible = 100;
+    SetDarkTheme = 101;
+    SetLightTheme = 102;
+    ToggleTheme = 103;
 }
 
 message Position {
diff --git a/zellij-utils/src/plugin_api/action.rs b/zellij-utils/src/plugin_api/action.rs
index cbd62e5b..cd3e1522 100644
--- a/zellij-utils/src/plugin_api/action.rs
+++ b/zellij-utils/src/plugin_api/action.rs
@@ -611,6 +611,18 @@ impl TryFrom<ProtobufAction> for Action {
                 Some(_) => Err("Detach should not have a payload"),
                 None => Ok(Action::Detach),
             },
+            Some(ProtobufActionName::SetDarkTheme) => match protobuf_action.optional_payload {
+                Some(_) => Err("SetDarkTheme should not have a payload"),
+                None => Ok(Action::SetDarkTheme),
+            },
+            Some(ProtobufActionName::SetLightTheme) => match protobuf_action.optional_payload {
+                Some(_) => Err("SetLightTheme should not have a payload"),
+                None => Ok(Action::SetLightTheme),
+            },
+            Some(ProtobufActionName::ToggleTheme) => match protobuf_action.optional_payload {
+                Some(_) => Err("ToggleTheme should not have a payload"),
+                None => Ok(Action::ToggleTheme),
+            },
             Some(ProtobufActionName::LeftClick) => match protobuf_action.optional_payload {
                 Some(OptionalPayload::LeftClickPayload(payload)) => {
                     let position = payload.try_into()?;
@@ -1567,6 +1579,18 @@ impl TryFrom<Action> for ProtobufAction {
                 name: ProtobufActionName::Detach as i32,
                 optional_payload: None,
             }),
+            Action::SetDarkTheme => Ok(ProtobufAction {
+                name: ProtobufActionName::SetDarkTheme as i32,
+                optional_payload: None,
+            }),
+            Action::SetLightTheme => Ok(ProtobufAction {
+                name: ProtobufActionName::SetLightTheme as i32,
+                optional_payload: None,
+            }),
+            Action::ToggleTheme => Ok(ProtobufAction {
+                name: ProtobufActionName::ToggleTheme as i32,
+                optional_payload: None,
+            }),
             Action::LaunchOrFocusPlugin {
                 plugin: run_plugin_or_alias,
                 should_float,
diff --git a/zellij-utils/src/plugin_api/event.proto b/zellij-utils/src/plugin_api/event.proto
index 3c3a8490..5334f434 100644
--- a/zellij-utils/src/plugin_api/event.proto
+++ b/zellij-utils/src/plugin_api/event.proto
@@ -68,6 +68,7 @@ enum EventType {
     PaneRenderReportWithAnsi = 43;
     InitialKeybinds = 44;
     CommandChanged = 45;
+    HostTerminalThemeChanged = 46;
 }
 
 message EventNameList {
@@ -115,9 +116,19 @@ message Event {
     PaneRenderReportPayload pane_render_report_with_ansi_payload = 37;
     InitialKeybindsPayload initial_keybinds_payload = 38;
     CommandChangedPayload command_changed_payload = 39;
+    HostTerminalThemeChangedPayload host_terminal_theme_changed_payload = 40;
   }
 }
 
+message HostTerminalThemeChangedPayload {
+  HostTerminalThemeIndication mode = 1;
+}
+
+enum HostTerminalThemeIndication {
+  Dark = 0;
+  Light = 1;
+}
+
 message CwdChangedPayload {
   PaneId pane_id = 1;
   string new_cwd = 2;
diff --git a/zellij-utils/src/plugin_api/event.rs b/zellij-utils/src/plugin_api/event.rs
index 6f138742..af421fac 100644
--- a/zellij-utils/src/plugin_api/event.rs
+++ b/zellij-utils/src/plugin_api/event.rs
@@ -11,6 +11,8 @@ pub use super::generated_api::api::{
         CopyDestination as ProtobufCopyDestination, CwdChangedPayload as ProtobufCwdChangedPayload,
         Event as ProtobufEvent, EventNameList as ProtobufEventNameList,
         EventType as ProtobufEventType, FileMetadata as ProtobufFileMetadata,
+        HostTerminalThemeChangedPayload as ProtobufHostTerminalThemeChangedPayload,
+        HostTerminalThemeIndication as ProtobufHostTerminalThemeIndication,
         InputModeKeybinds as ProtobufInputModeKeybinds, KdlError as ProtobufKdlError,
         KdlErrorVariant as ProtobufKdlErrorVariant, KeyBind as ProtobufKeyBind,
         LayoutInfo as ProtobufLayoutInfo, LayoutMetadata as ProtobufLayoutMetadata,
@@ -35,11 +37,11 @@ pub use super::generated_api::api::{
 };
 #[allow(hidden_glob_reexports)]
 use crate::data::{
-    ClientId, ClientInfo, CopyDestination, Event, EventType, FileMetadata, InputMode,
-    KeyWithModifier, LayoutInfo, LayoutMetadata, ModeInfo, Mouse, PaneContents, PaneId, PaneInfo,
-    PaneManifest, PaneMetadata, PaneScrollbackResponse, PermissionStatus, PluginCapabilities,
-    PluginInfo, SelectedText, SessionInfo, Style, TabInfo, TabMetadata, WebServerStatus,
-    WebSharing,
+    ClientId, ClientInfo, CopyDestination, Event, EventType, FileMetadata, HostTerminalThemeMode,
+    InputMode, KeyWithModifier, LayoutInfo, LayoutMetadata, ModeInfo, Mouse, PaneContents, PaneId,
+    PaneInfo, PaneManifest, PaneMetadata, PaneScrollbackResponse, PermissionStatus,
+    PluginCapabilities, PluginInfo, SelectedText, SessionInfo, Style, TabInfo, TabMetadata,
+    WebServerStatus, WebSharing,
 };
 
 use crate::errors::prelude::*;
@@ -578,6 +580,14 @@ impl TryFrom<ProtobufEvent> for Event {
                 },
                 _ => Err("Malformed payload for InitialKeybinds Event"),
             },
+            Some(ProtobufEventType::HostTerminalThemeChanged) => match protobuf_event.payload {
+                Some(ProtobufEventPayload::HostTerminalThemeChangedPayload(p)) => {
+                    let mode = ProtobufHostTerminalThemeIndication::from_i32(p.mode)
+                        .ok_or("Unknown HostTerminalThemeIndication")?;
+                    Ok(Event::HostTerminalThemeChanged(mode.into()))
+                },
+                _ => Err("Malformed payload for HostTerminalThemeChanged Event"),
+            },
             None => Err("Unknown Protobuf Event"),
         }
     }
@@ -1109,6 +1119,16 @@ impl TryFrom<Event> for ProtobufEvent {
                     },
                 )),
             }),
+            Event::HostTerminalThemeChanged(mode) => {
+                let proto_mode: ProtobufHostTerminalThemeIndication = mode.into();
+                let payload = ProtobufHostTerminalThemeChangedPayload {
+                    mode: proto_mode as i32,
+                };
+                Ok(ProtobufEvent {
+                    name: ProtobufEventType::HostTerminalThemeChanged as i32,
+                    payload: Some(event::Payload::HostTerminalThemeChangedPayload(payload)),
+                })
+            },
             Event::InitialKeybinds(keybinds) => {
                 let mut protobuf_keybinds: Vec<ProtobufInputModeKeybinds> = vec![];
                 for (input_mode, input_mode_keybinds) in keybinds {
@@ -2057,6 +2077,7 @@ impl TryFrom<ProtobufEventType> for EventType {
             ProtobufEventType::PluginConfigurationChanged => EventType::PluginConfigurationChanged,
             ProtobufEventType::HighlightClicked => EventType::HighlightClicked,
             ProtobufEventType::InitialKeybinds => EventType::InitialKeybinds,
+            ProtobufEventType::HostTerminalThemeChanged => EventType::HostTerminalThemeChanged,
         })
     }
 }
@@ -2110,10 +2131,29 @@ impl TryFrom<EventType> for ProtobufEventType {
             EventType::PluginConfigurationChanged => ProtobufEventType::PluginConfigurationChanged,
             EventType::HighlightClicked => ProtobufEventType::HighlightClicked,
             EventType::InitialKeybinds => ProtobufEventType::InitialKeybinds,
+            EventType::HostTerminalThemeChanged => ProtobufEventType::HostTerminalThemeChanged,
         })
     }
 }
 
+impl From<HostTerminalThemeMode> for ProtobufHostTerminalThemeIndication {
+    fn from(mode: HostTerminalThemeMode) -> Self {
+        match mode {
+            HostTerminalThemeMode::Dark => ProtobufHostTerminalThemeIndication::Dark,
+            HostTerminalThemeMode::Light => ProtobufHostTerminalThemeIndication::Light,
+        }
+    }
+}
+
+impl From<ProtobufHostTerminalThemeIndication> for HostTerminalThemeMode {
+    fn from(mode: ProtobufHostTerminalThemeIndication) -> Self {
+        match mode {
+            ProtobufHostTerminalThemeIndication::Dark => HostTerminalThemeMode::Dark,
+            ProtobufHostTerminalThemeIndication::Light => HostTerminalThemeMode::Light,
+        }
+    }
+}
+
 impl From<ProtobufResurrectableSession> for (String, Duration) {
     fn from(protobuf_resurrectable_session: ProtobufResurrectableSession) -> (String, Duration) {
         (