#![recursion_limit = "1024"]

#[cfg(test)]
mod union_async_spawn_tests {
    use futures::future::{err, ok, ready};
    use std::error::Error;
    use std::thread;
    use tokio::runtime::Runtime;
    use union::union_async_spawn;

    type BoxedError = Box<dyn Error + Send + Sync>;

    type Result<T> = std::result::Result<T, BoxedError>;

    type _Result<T, E> = std::result::Result<T, E>;

    async fn get_three() -> u16 {
        3
    }

    async fn get_ok_four() -> Result<u16> {
        Ok(4)
    }

    async fn get_some_five() -> Option<u16> {
        Some(5)
    }

    async fn get_err() -> Result<u16> {
        Err("error".into())
    }

    async fn get_none() -> Option<u16> {
        None
    }

    fn add_one_sync(v: u16) -> u16 {
        v + 1
    }

    async fn add_one(v: u16) -> u16 {
        v + 1
    }

    async fn add_one_ok(v: u16) -> Result<u16> {
        Ok(add_one(v).await)
    }

    async fn to_err(v: u16) -> Result<u16> {
        Err(v.to_string().into())
    }

    async fn to_some(v: u16) -> Option<u16> {
        Some(v)
    }

    fn add_one_to_ok(v: Result<u16>) -> Result<u16> {
        v.map(add_one_sync)
    }

    #[test]
    fn it_produces_n_branches_with_length_1() {
        let rt = Runtime::new().unwrap();
        rt.block_on(async {
            let product = union_async_spawn! {
                ok(2u16),
                ok(get_three().await),
                get_ok_four(),
                ok(get_some_five().await.unwrap()),
                and_then => |a, b, c, d| ok(a * b * c * d)
            };

            assert_eq!(product.await.unwrap(), 120u16);

            let err = union_async_spawn! {
                ok(2u16),
                ok(get_three().await),
                get_ok_four(),
                get_err(),
                and_then => |a, b, c, d| ok(a * b * c * d)
            };

            assert_eq!(
                format!("{:?}", err.await.unwrap_err()),
                format!("{:?}", get_err().await.unwrap_err())
            );
        });
    }

    #[test]
    fn it_produces_n_branches_with_any_length() {
        let rt = Runtime::new().unwrap();
        rt.block_on(async {
            let product = union_async_spawn! {
                ok(2u16).map(add_one_to_ok).and_then(add_one_ok), //4
                ok(get_three().await).and_then(add_one_ok).map(add_one_to_ok).map(add_one_to_ok).map(add_one_to_ok), //7
                get_ok_four().map(add_one_to_ok), //5
                get_some_five().map(|v| v.ok_or("unreachable".into())).and_then(to_err).and_then(add_one_ok).or_else(|_| ok(5)), // 5
                and_then => |a, b, c, d| ok(a * b * c * d)
            };

            assert_eq!(product.await.unwrap(), 700u16);

            let err = union_async_spawn! {
                ok(2).map(add_one_to_ok),
                ok(get_three().await).and_then(to_err),
                get_ok_four(),
                get_err(),
                map => |a, b, c, d| a * b * c * d
            };

            assert_eq!(
                format!("{:?}", err.await.unwrap_err()),
                format!("{:?}", to_err(get_three().await).await.unwrap_err())
            );
        });
    }
    #[test]
    fn it_produces_n_branches_with_any_length_using_combinators() {
        let rt = Runtime::new().unwrap();
        rt.block_on(async {
            let product = union_async_spawn! {
                ok(2u16) |> add_one_to_ok => add_one_ok, //4
                ok(get_three().await) => add_one_ok |> add_one_to_ok |> add_one_to_ok |> add_one_to_ok, //7
                get_ok_four() |> add_one_to_ok, //5
                get_some_five() |> |v| v.ok_or("hello".into()) |> add_one_to_ok => to_err => add_one_ok <= |_| ok(5), // 5
                map => |a, b, c, d| a * b * c * d
            };

            assert_eq!(product.await.unwrap(), 700);

            let sum = union_async_spawn! {
                2u16 -> ok |> add_one_to_ok => add_one_ok, //4
                get_three().await -> ok => add_one_ok |> add_one_to_ok |> add_one_to_ok |> add_one_to_ok, //7
                get_ok_four() |> add_one_to_ok, //5
                get_some_five() |> |v| v.ok_or("hello".into()) |> add_one_to_ok => to_err => add_one_ok <= |_| ok(5), // 5
                and_then => |a, b, c, d| ok(a + b + c + d)
            };

            assert_eq!(sum.await.unwrap(), 21);

            let err: Result<u16> = union_async_spawn! {
                ok(2) |> add_one_to_ok,
                ok(get_three().await) => to_err,
                get_ok_four() => |_| err("some error".into()),
                get_err(),
                map => |a: u16, b: u16, c: u16, d: u16| a * b * c * d
            }
            .await;

            assert_eq!(
                format!("{:?}", err.unwrap_err()),
                format!("{:?}", to_err(get_three().await).await.unwrap_err())
            );

            let none = union_async_spawn! {
                2 -> to_some,
                get_some_five().await -> ready |> |_| None,
                get_ok_four() |> |v| v.ok(),
                get_none(),
                map => |a: u16, b: u16, c: u16, d: u16| a * b * c * d
            };

            assert_eq!(none.await, None);
        });
    }

    #[test]
    fn it_tests_handler_behaviour() {
        let rt = Runtime::new().unwrap();
        rt.block_on(
            async {
                let ok_value = union_async_spawn! {
                    ok(2u16),
                    ok(3u16),
                    get_ok_four(),
                    and_then => |a, b, c| ok::<Option<u16>, _>(None)
                };

                assert_eq!(ok_value.await.unwrap(), None);

                let err_value = union_async_spawn! {
                    ok(2u16),
                    ok(3u16),
                    get_ok_four(),
                    and_then => |a, b, c| to_err(a)
                };

                assert_eq!(format!("{:?}", err_value.await.unwrap_err()), format!("{:?}", to_err(2).await.unwrap_err()));

                let some = union_async_spawn! {
                    ready(Some(2u16)),
                    ready(Some(3u16)),
                    get_some_five(),
                    map => |a, b, c| a
                };

                assert_eq!(some.await, Some(2u16));

                let none = union_async_spawn! {
                    ready(Some(2u16)),
                    ready(Some(3u16)),
                    get_some_five(),
                    then => |a, b, c| ready(None::<u16>)
                };

                assert_eq!(none.await, None);

                let some = union_async_spawn! {
                    ready(Some(2u16)),
                    ready(Some(3u16)),
                    get_some_five(),
                    map => |a, b, c| a + b + c
                };

                assert_eq!(some.await, Some(10));

                let none = union_async_spawn! {
                    ready(Some(2u16)),
                    None -> ready,
                    get_some_five(),
                    map => |a: u16, b: u16, c: u16| a + b + c
                };

                assert_eq!(none.await, None);

                let ok_value= union_async_spawn! {
                    ok(2u16),
                    ok(3u16),
                    get_ok_four(),
                    then => |a: Result<u16>, b: Result<u16>, c: Result<u16>| ok::<_, u8>(a.unwrap() + b.unwrap() + c.unwrap())
                };

                assert_eq!(ok_value.await.unwrap(), 9u16);

                let err_value = union_async_spawn! {
                    ok(2u16),
                    ok(3u16),
                    get_ok_four(),
                    then => |a: Result<u16>, b: Result<u16>, c: Result<u16>| err::<u16, _>(a.unwrap() + b.unwrap() + c.unwrap())
                };

                assert_eq!(err_value.await, Err(9));
            }
        );
    }

    #[test]
    fn it_tests_steps() {
        let rt = Runtime::new().unwrap();
        rt.block_on(async {
            let product = union_async_spawn! {
                let branch_0 = ok(2u16) ~|> {
                    let branch_0 = branch_0.as_ref().ok().map(Clone::clone);
                    let branch_1 = branch_1.as_ref().ok().map(Clone::clone);
                    let branch_2 = branch_2.as_ref().ok().map(Clone::clone);
                    let branch_3 = branch_3.as_ref().map(Clone::clone);
                    move |value: Result<u16>| {
                        assert_eq!(branch_0, value.as_ref().ok().map(Clone::clone));
                        assert_eq!(branch_1, Some(3));
                        assert_eq!(branch_2, Some(4));
                        assert_eq!(branch_3, Some(5));
                        value.map(add_one_sync)
                    }
                } ~=> add_one_ok, //4
                let branch_1 = get_three().await -> ok ~=> add_one_ok ~|> |value| value |> {
                    let branch_0 = branch_0.as_ref().ok().map(Clone::clone);
                    let branch_1 = branch_1.as_ref().ok().map(Clone::clone);
                    let branch_2 = branch_2.as_ref().ok().map(Clone::clone);
                    let branch_3 = branch_3.as_ref().ok().map(Clone::clone);
                    move |value: Result<u16>| {
                        assert_eq!(branch_0, Some(3));
                        assert_eq!(branch_1, value.as_ref().ok().map(Clone::clone));
                        assert_eq!(branch_2, Some(5));
                        assert_eq!(branch_3, Some(5));
                        value.map(add_one_sync)
                    }
                } ~|> add_one_to_ok ~|> add_one_to_ok, //7
                let branch_2 = get_ok_four() ~|> add_one_to_ok, //5
                let branch_3 = get_some_five() ~|> |v| v.ok_or("unreachable".into()) ~|> add_one_to_ok ~=> to_err <= |_| ok(5) ~=> add_one_ok, // 6
                map => |a, b, c, d| a * b * c * d
            };

            assert_eq!(product.await.unwrap(), 840);
        });
    }
    #[test]
    fn it_checks_mutli_threading() {
        let rt = Runtime::new().unwrap();
        rt.block_on(async {
            use futures::lock::Mutex;
            use std::sync::Arc;
            use std::time::Duration;

            let values = Arc::new(Mutex::new(Vec::new()));

            let (values0, values1, values2) = (values.clone(), values.clone(), values.clone());

            let _ = union_async_spawn! {
                ok((values0, 1u16)) => |(values, value)| async move {
                    values.lock().await.push(value);
                    // !!! Don't use std::thread::sleep to wait inside future because it will block executor thread !!!
                    // It's used here only to show that futures are executed on multi thread executor.
                    thread::sleep(Duration::from_secs(1));
                    let mut values = values.lock().await;
                    values.sort();
                    assert_eq!(values[..], [1, 2, 3]);
                    values.pop();
                    Ok::<_, BoxedError>(())
                },
                ok((values1, 2u16)) => |(values, value)| async move {
                    values.lock().await.push(value);
                    // !!! Don't use std::thread::sleep to wait inside future because it will block executor thread !!!
                    // It's used here only to show that futures are executed on multi thread executor.
                    thread::sleep(Duration::from_secs(2));
                    let mut values = values.lock().await;
                    values.sort();
                    assert_eq!(values[..], [1, 2]);
                    values.pop();
                    Ok::<_, BoxedError>(())
                },
                ok((values2, 3u16)) => |(values, value)| async move {
                    values.lock().await.push(value);
                    // !!! Don't use std::thread::sleep to wait inside future because it will block executor thread !!!
                    // It's used here only to show that futures are executed on multi thread executor.
                    thread::sleep(Duration::from_secs(3));
                    let mut values = values.lock().await;
                    values.sort();
                    assert_eq!(values[..], [1]);
                    values.pop();
                    Ok::<_, BoxedError>(())
                },
                then => move |_, _, _| async move {
                    assert_eq!(values.lock().await.len(), 0);
                    Ok::<_, BoxedError>(())
                }
            }
            .await
            .unwrap();
        });
    }

    #[test]
    fn it_produces_tuple() {
        let rt = Runtime::new().unwrap();
        rt.block_on(async {
            let values = union_async_spawn! { ok::<_,u8>(2), ok::<_,u8>(3) }.await;
            assert_eq!(values.unwrap(), (2, 3));
        });
    }

    #[test]
    fn it_produces_single_value() {
        let rt = Runtime::new().unwrap();
        rt.block_on(async {
            let value = union_async_spawn! { ready(Some(1)) }.await;
            assert_eq!(value.unwrap(), 1);
        });
    }

    #[allow(unreachable_code)]
    #[test]
    fn it_creates_unpolled_future() {
        let rt = Runtime::new().unwrap();
        rt.block_on(async {
            let _fut = union_async_spawn! {
                ready(panic!()),
                ready(unreachable!()),
                then => |a: Result<u8>, b: Result<u8>| ready(a)
            };
        });
    }

    #[test]
    fn it_cant_work_without_tokio() {
        assert!(
            ::std::panic::catch_unwind(|| ::futures::executor::block_on(async {
                let failure = union_async_spawn! { ready(2u16) };
                failure.await
            }))
            .is_err()
        );
    }
}