feat(terminal): add runtime renderer switch

app/src/pages/terminal.rs

@@ -1,22 +1,91 @@
 use leptos::prelude::*;
 
 use crate::components::layout::{AdminShell, Breadcrumb};
-use crate::terminal::{TerminalPanel, TerminalRenderEvent};
+use crate::terminal::{Renderer, TerminalOptions, TerminalPanel, TerminalRenderEvent};
 
 #[component]
 pub fn TerminalPage() -> impl IntoView {
+    let renderer = RwSignal::new(initial_terminal_renderer());
+    let terminal_options = Signal::derive(move || TerminalOptions {
+        renderer: renderer.get(),
+        ..TerminalOptions::default()
+    });
     let on_render = Callback::new(update_terminal_bench_probe);
 
     view! {
         <AdminShell>
             <Breadcrumb current="浏览器终端" />
             <section class="cowa-work-surface terminal-page-shell">
-                <TerminalPanel on_render=on_render />
+                <TerminalRendererSwitch renderer=renderer />
+                <TerminalPanel options=terminal_options on_render=on_render />
             </section>
         </AdminShell>
     }
 }
 
+#[component]
+fn TerminalRendererSwitch(renderer: RwSignal<Renderer>) -> impl IntoView {
+    view! {
+        <div class="terminal-page-toolbar" role="toolbar" aria-label="终端渲染器">
+            <span class="terminal-renderer-label">"Renderer"</span>
+            <RendererButton renderer=renderer value=Renderer::WebGl label="WebGL" />
+            <RendererButton renderer=renderer value=Renderer::Canvas label="Canvas" />
+            <RendererButton renderer=renderer value=Renderer::Dom label="DOM" />
+        </div>
+    }
+}
+
+#[component]
+fn RendererButton(
+    renderer: RwSignal<Renderer>,
+    value: Renderer,
+    label: &'static str,
+) -> impl IntoView {
+    view! {
+        <button
+            type="button"
+            class="terminal-renderer-option"
+            class=("is-active", move || renderer.get() == value)
+            aria-pressed=move || (renderer.get() == value).to_string()
+            on:click=move |_| renderer.set(value)
+        >
+            {label}
+        </button>
+    }
+}
+
+#[cfg(target_arch = "wasm32")]
+fn initial_terminal_renderer() -> Renderer {
+    web_sys::window()
+        .and_then(|window| window.location().search().ok())
+        .and_then(|query| renderer_from_query(&query))
+        .unwrap_or_default()
+}
+
+#[cfg(not(target_arch = "wasm32"))]
+fn initial_terminal_renderer() -> Renderer {
+    Renderer::default()
+}
+
+#[cfg(any(target_arch = "wasm32", test))]
+fn renderer_from_query(query: &str) -> Option<Renderer> {
+    query
+        .trim_start_matches('?')
+        .split('&')
+        .filter_map(|part| part.split_once('='))
+        .find_map(|(key, value)| (key == "renderer").then(|| parse_renderer(value)).flatten())
+}
+
+#[cfg(any(target_arch = "wasm32", test))]
+fn parse_renderer(value: &str) -> Option<Renderer> {
+    match value.to_ascii_lowercase().as_str() {
+        "webgl" | "web-gl" => Some(Renderer::WebGl),
+        "canvas" | "canvas2d" | "canvas-2d" => Some(Renderer::Canvas),
+        "dom" => Some(Renderer::Dom),
+        _ => None,
+    }
+}
+
 #[cfg(target_arch = "wasm32")]
 fn update_terminal_bench_probe(event: TerminalRenderEvent) {
     use wasm_bindgen::JsValue;
@@ -87,3 +156,28 @@ fn update_terminal_bench_probe(event: TerminalRenderEvent) {
 
 #[cfg(not(target_arch = "wasm32"))]
 fn update_terminal_bench_probe(_event: TerminalRenderEvent) {}
+
+#[cfg(test)]
+mod tests {
+    use super::*;
+
+    #[test]
+    fn renderer_query_parses_supported_values() {
+        assert_eq!(
+            renderer_from_query("?renderer=webgl"),
+            Some(Renderer::WebGl)
+        );
+        assert_eq!(
+            renderer_from_query("?foo=1&renderer=canvas2d"),
+            Some(Renderer::Canvas)
+        );
+        assert_eq!(renderer_from_query("?renderer=dom"), Some(Renderer::Dom));
+    }
+
+    #[test]
+    fn renderer_query_ignores_unknown_values() {
+        assert_eq!(renderer_from_query("?renderer=auto"), None);
+        assert_eq!(renderer_from_query("?other=webgl"), None);
+        assert_eq!(renderer_from_query(""), None);
+    }
+}