OpenTUI is here (#2685)

packages/opencode/src/cli/cmd/tui/util/editor.ts

@@ -0,0 +1,31 @@
+import { defer } from "@/util/defer"
+import { rm } from "node:fs/promises"
+import { tmpdir } from "node:os"
+import { join } from "node:path"
+import { CliRenderer } from "@opentui/core"
+
+export namespace Editor {
+  export async function open(opts: { value: string; renderer: CliRenderer }): Promise<string | undefined> {
+    const editor = process.env["EDITOR"]
+    if (!editor) return
+
+    const filepath = join(tmpdir(), `${Date.now()}.md`)
+    await using _ = defer(async () => rm(filepath, { force: true }))
+
+    await Bun.write(filepath, opts.value)
+    opts.renderer.suspend()
+    opts.renderer.currentRenderBuffer.clear()
+    const parts = editor.split(" ")
+    const proc = Bun.spawn({
+      cmd: [...parts, filepath],
+      stdin: "inherit",
+      stdout: "inherit",
+      stderr: "inherit",
+    })
+    await proc.exited
+    const content = await Bun.file(filepath).text()
+    opts.renderer.resume()
+    opts.renderer.requestRender()
+    return content || undefined
+  }
+}