package server_test

import (
	"sync"
	"testing"

	"golang.org/x/net/context"
	air "zombiezen.com/go/capnproto2/internal/aircraftlib"
	. "zombiezen.com/go/capnproto2/server"
)

type echoImpl struct{}

func (echoImpl) Echo(call air.Echo_echo) error {
	in, err := call.Params.In()
	if err != nil {
		return err
	}
	call.Results.SetOut(in + in)
	return nil
}

func TestServerCall(t *testing.T) {
	echo := air.Echo_ServerToClient(echoImpl{})
	defer func() {
		if err := echo.Client.Close(); err != nil {
			t.Error("Close:", err)
		}
	}()

	result, err := echo.Echo(context.Background(), func(p air.Echo_echo_Params) error {
		err := p.SetIn("foo")
		return err
	}).Struct()

	if err != nil {
		t.Errorf("echo.Echo() error: %v", err)
	}
	if out, err := result.Out(); err != nil {
		t.Errorf("echo.Echo() error: %v", err)
	} else if out != "foofoo" {
		t.Errorf("echo.Echo() = %q; want %q", out, "foofoo")
	}
}

type callSeq uint32

func (seq *callSeq) GetNumber(call air.CallSequence_getNumber) error {
	call.Results.SetN(uint32(*seq))
	*seq++
	return nil
}

type lockCallSeq struct {
	n  uint32
	mu sync.Mutex
}

func (seq *lockCallSeq) GetNumber(call air.CallSequence_getNumber) error {
	seq.mu.Lock()
	defer seq.mu.Unlock()
	Ack(call.Options)

	call.Results.SetN(seq.n)
	seq.n++
	return nil
}

func TestServerCallOrder(t *testing.T) {
	seq := air.CallSequence_ServerToClient(new(callSeq))
	testCallOrder(t, seq)
	if err := seq.Client.Close(); err != nil {
		t.Error("Close:", err)
	}
}

func TestServerCallOrderWithCustomLocks(t *testing.T) {
	seq := air.CallSequence_ServerToClient(new(lockCallSeq))
	testCallOrder(t, seq)
	if err := seq.Client.Close(); err != nil {
		t.Error("Close:", err)
	}
}

func testCallOrder(t *testing.T, seq air.CallSequence) {
	ctx := context.Background()
	send := func() air.CallSequence_getNumber_Results_Promise {
		return seq.GetNumber(ctx, nil)
	}
	check := func(p air.CallSequence_getNumber_Results_Promise, n uint32) {
		result, err := p.Struct()
		if err != nil {
			t.Errorf("seq.getNumber() error: %v; want %d", err, n)
		} else if result.N() != n {
			t.Errorf("seq.getNumber() = %d; want %d", result.N(), n)
		}
	}

	call0 := send()
	call1 := send()
	call2 := send()
	call3 := send()
	call4 := send()

	check(call0, 0)
	check(call1, 1)
	check(call2, 2)
	check(call3, 3)
	check(call4, 4)
}