event lifecycle

1 files changed, 37 insertions, 1 deletions

diff --git a/src/main.zig b/src/main.zig
index 7905347..34a687a 100644
--- a/src/main.zig
+++ b/src/main.zig
@@ -2,6 +2,7 @@ const std = @import("std");
 const panto = @import("panto");
 const lua_bridge = @import("lua_bridge.zig");
 const lua_runtime = @import("lua_runtime.zig");
+const lua_event_bridge = @import("lua_event_bridge.zig");
 const extension_loader = @import("extension_loader.zig");
 const panto_home = @import("panto_home.zig");
 const luarocks_runtime = @import("luarocks_runtime.zig");
@@ -24,6 +25,7 @@ const tui_theme = @import("tui_theme.zig");
 const tui_component = @import("tui_component.zig");
 const tui_engine = @import("tui_engine.zig");
 const tui_components = @import("tui_components.zig");
+const tui_event = @import("tui_event.zig");
 const tui_app = @import("tui_app.zig");
 
 // Shorthand alias for the Lua C API. The bridge module owns the actual
@@ -43,6 +45,7 @@ test {
     std.testing.refAllDecls(@This());
     _ = lua_bridge;
     _ = lua_runtime;
+    _ = lua_event_bridge;
     _ = extension_loader;
     _ = panto_home;
     _ = luarocks_runtime;
@@ -61,6 +64,7 @@ test {
     _ = tui_component;
     _ = tui_engine;
     _ = tui_components;
+    _ = tui_event;
     _ = tui_app;
 }
 
@@ -401,7 +405,7 @@ pub fn main(init: std.process.Init) !void {
     try command_compaction.register(&cmd_registry);
 
     // Append slash commands declared by Lua extensions via
-    // `panto.register_command`. A name collision with a builtin (or
+    // `panto.ext.register_command`. A name collision with a builtin (or
     // between two extensions) surfaces as `error.DuplicateCommand` and
     // aborts startup, matching the tool-name collision policy.
     for (rt.commandList()) |lua_cmd| {
@@ -485,6 +489,38 @@ pub fn main(init: std.process.Init) !void {
     );
     defer app.deinit();
 
+    // Wire the Lua extension UI event bridge to the App's event bus: this
+    // registers every `panto.ext.on(...)` handler (harvested at extension
+    // load time) into the bus, in registration order, so extensions can
+    // wrap/replace built-in components and a Lua `panto.ext.emit(...)` can
+    // drive the same bus. With no Lua handlers this is a no-op.
+    try rt.eventBridge().attachBus(app.eventBus());
+
+    // Install the override-release hook so a Lua-backed override that is
+    // SUPERSEDED by a later mid-stream swap (e.g. a `tool_details` handler
+    // replacing the `tool (?)` default's prior override) has its luaL_ref +
+    // RenderCache freed. Without this, each swapped Lua component would leak
+    // for the life of the runtime. The hook recognizes a bridged component by
+    // its vtable identity and ignores native components (see
+    // `EventBridge.releaseOverride`).
+    //
+    // TEARDOWN ORDERING CONTRACT (load-bearing — do not reorder these decls):
+    //   `app` is declared AFTER `rt`, so `defer app.deinit()` runs BEFORE
+    //   `defer rt.deinit()` (defers are LIFO). The bridge (owned by `rt`)
+    //   therefore outlives the App's teardown. This matters because the
+    //   release hook below points into the bridge: if the bridge were freed
+    //   first, any later hook invocation would be a use-after-free.
+    //   It is safe today because `App.deinit` frees only its own default
+    //   `kind` boxes and NEVER invokes `override_release_fn` — the surviving
+    //   (non-superseded) Lua overrides are freed by `EventBridge.deinit` when
+    //   `rt.deinit()` runs. The hook fires only during live mid-stream swaps,
+    //   while both App and bridge are alive. If you ever make `App.deinit`
+    //   call the release hook, or move `rt` to outlive `app`, revisit this.
+    app.setOverrideRelease(
+        @ptrCast(rt.eventBridge()),
+        lua_event_bridge.EventBridge.releaseOverrideThunk,
+    );
+
     const Flusher = struct {
         fn flush(ctx: *anyopaque) void {
             const fw: *std.Io.File.Writer = @ptrCast(@alignCast(ctx));