import { describe, expect, test } from "bun:test"

import { Readable } from "node:stream"

import { INTERACTIVE_INPUT_ERROR, resolveInteractiveStdin } from "@/cli/cmd/run/runtime.stdin"

function stream(isTTY: boolean) {

return Object.assign(new Readable({ read() {} }), { isTTY }) as NodeJS.ReadStream

}

describe("run interactive stdin", () => {

test("reuses stdin when it is already a tty", () => {

const stdin = stream(true)

const seen: string[] = []

const result = resolveInteractiveStdin(

stdin,

(path) => {

seen.push(path)

return stream(true)

},

"linux",

)

expect(result.stdin).toBe(stdin)

expect(result.cleanup).toBeUndefined()

expect(seen).toEqual([])

})

test("opens the controlling terminal when stdin is piped", () => {

const tty = stream(true)

const seen: string[] = []

const result = resolveInteractiveStdin(

stream(false),

(path) => {

seen.push(path)

return tty

},

"linux",

)

expect(result.stdin).toBe(tty)

expect(seen).toEqual(["/dev/tty"])

result.cleanup?.()

expect(tty.destroyed).toBe(true)

})

test("uses CONIN$ on windows", () => {

const seen: string[] = []

resolveInteractiveStdin(

stream(false),

(path) => {

seen.push(path)

return stream(true)

},

"win32",

)

expect(seen).toEqual(["CONIN$"])

})

test("throws a clear error when no controlling terminal is available", () => {

expect(() =>

resolveInteractiveStdin(

stream(false),

() => {

throw new Error("open failed")

},

"linux",

),

).toThrow(INTERACTIVE_INPUT_ERROR)

})

})