package lang

import (
	"strings"
	"testing"
)

func TestGenerateStructuredCoroutines(t *testing.T) {
	prog, err := Parse(`package demo
suspend fun load(): Int { delay(1); return 42 }
fun main() {
    runBlocking {
        coroutineScope {
            launch { delay(1) }
            val result = async<Int> { return load() }
            println(result.await())
        }
    }
}`)
	if err != nil {
		t.Fatal(err)
	}
	out, err := GenerateGo(prog)
	if err != nil {
		t.Fatal(err)
	}
	for _, want := range []string{"func load(gotlinScope *GotlinCoroutineScope) int", "gotlinScope.Delay(1)", "gotlinScope.Launch", "gotlinAsync[int]", "load(gotlinScope)", ".await()", "gotlinRunBlocking"} {
		if !strings.Contains(string(out), want) {
			t.Fatalf("missing %q:\n%s", want, out)
		}
	}
}

func TestSuspendFunctionRequiresScope(t *testing.T) {
	prog, err := Parse(`package demo
suspend fun load(): Int { return 1 }
fun main() { println(load()) }`)
	if err != nil {
		t.Fatal(err)
	}
	_, err = GenerateGo(prog)
	if err == nil || !strings.Contains(err.Error(), "requires a coroutine scope") {
		t.Fatalf("unexpected error: %v", err)
	}
}

func TestWorkerAndBareGoAreRemoved(t *testing.T) {
	for _, source := range []string{`package demo worker Counter { var count = 0 }`, `package demo fun main() { go println("x") }`} {
		if _, err := Parse(source); err == nil {
			t.Fatalf("deprecated concurrency syntax parsed: %s", source)
		}
	}
}

func TestRunBlockingCancelsAndJoinsChildrenOnPanic(t *testing.T) {
	prog, err := Parse(`package demo fun main() { runBlocking { launch { delay(1) }; panic("failed") } }`)
	if err != nil {
		t.Fatal(err)
	}
	out, err := GenerateGo(prog)
	if err != nil {
		t.Fatal(err)
	}
	for _, want := range []string{"scope.cancel()", "scope.workers.Wait()", "panic(value)", "gotlinRunBlocking"} {
		if !strings.Contains(string(out), want) {
			t.Fatalf("missing %q:\n%s", want, out)
		}
	}
}