package client

import (
	"fmt"
	"net"
	"sync/atomic"
	"testing"
	"time"

	"github.com/hashicorp/nomad/client/config"
	"github.com/hashicorp/nomad/nomad"
	"github.com/hashicorp/nomad/nomad/structs"
	"github.com/hashicorp/nomad/testutil"
)

var nextPort uint32 = 16000

func getPort() int {
	return int(atomic.AddUint32(&nextPort, 1))
}

func testServer(t *testing.T, cb func(*nomad.Config)) (*nomad.Server, string) {
	// Setup the default settings
	config := nomad.DefaultConfig()
	config.Build = "unittest"
	config.DevMode = true
	config.RPCAddr = &net.TCPAddr{
		IP:   []byte{127, 0, 0, 1},
		Port: getPort(),
	}
	config.NodeName = fmt.Sprintf("Node %d", config.RPCAddr.Port)

	// Tighten the Serf timing
	config.SerfConfig.MemberlistConfig.BindAddr = "127.0.0.1"
	config.SerfConfig.MemberlistConfig.BindPort = getPort()
	config.SerfConfig.MemberlistConfig.SuspicionMult = 2
	config.SerfConfig.MemberlistConfig.RetransmitMult = 2
	config.SerfConfig.MemberlistConfig.ProbeTimeout = 50 * time.Millisecond
	config.SerfConfig.MemberlistConfig.ProbeInterval = 100 * time.Millisecond
	config.SerfConfig.MemberlistConfig.GossipInterval = 100 * time.Millisecond

	// Tighten the Raft timing
	config.RaftConfig.LeaderLeaseTimeout = 20 * time.Millisecond
	config.RaftConfig.HeartbeatTimeout = 40 * time.Millisecond
	config.RaftConfig.ElectionTimeout = 40 * time.Millisecond

	// Invoke the callback if any
	if cb != nil {
		cb(config)
	}

	// Create server
	server, err := nomad.NewServer(config)
	if err != nil {
		t.Fatalf("err: %v", err)
	}
	return server, config.RPCAddr.String()
}

func testClient(t *testing.T, cb func(c *config.Config)) *Client {
	conf := DefaultConfig()
	if cb != nil {
		cb(conf)
	}

	client, err := NewClient(conf)
	if err != nil {
		t.Fatalf("err: %v", err)
	}
	return client
}

func TestClient_StartStop(t *testing.T) {
	client := testClient(t, nil)
	if err := client.Shutdown(); err != nil {
		t.Fatalf("err: %v", err)
	}
}

func TestClient_RPC(t *testing.T) {
	s1, addr := testServer(t, nil)
	defer s1.Shutdown()

	c1 := testClient(t, func(c *config.Config) {
		c.Servers = []string{addr}
	})
	defer c1.Shutdown()

	// RPC should succeed
	testutil.WaitForResult(func() (bool, error) {
		var out struct{}
		err := c1.RPC("Status.Ping", struct{}{}, &out)
		return err == nil, err
	}, func(err error) {
		t.Fatalf("err: %v", err)
	})
}

func TestClient_RPC_Passthrough(t *testing.T) {
	s1, _ := testServer(t, nil)
	defer s1.Shutdown()

	c1 := testClient(t, func(c *config.Config) {
		c.RPCHandler = s1
	})
	defer c1.Shutdown()

	// RPC should succeed
	testutil.WaitForResult(func() (bool, error) {
		var out struct{}
		err := c1.RPC("Status.Ping", struct{}{}, &out)
		return err == nil, err
	}, func(err error) {
		t.Fatalf("err: %v", err)
	})
}

func TestClient_Fingerprint(t *testing.T) {
	c := testClient(t, nil)
	defer c.Shutdown()

	// Ensure kernel and arch are always present
	node := c.Node()
	if node.Attributes["kernel.name"] == "" {
		t.Fatalf("missing kernel.name")
	}
	if node.Attributes["arch"] == "" {
		t.Fatalf("missing arch")
	}
}

func TestClient_Drivers(t *testing.T) {
	c := testClient(t, nil)
	defer c.Shutdown()

	node := c.Node()
	if node.Attributes["driver.exec"] == "" {
		t.Fatalf("missing exec driver")
	}
}

func TestClient_Register(t *testing.T) {
	s1, _ := testServer(t, nil)
	defer s1.Shutdown()
	testutil.WaitForLeader(t, s1.RPC)

	c1 := testClient(t, func(c *config.Config) {
		c.RPCHandler = s1
	})
	defer c1.Shutdown()

	req := structs.NodeSpecificRequest{
		NodeID:       c1.Node().ID,
		QueryOptions: structs.QueryOptions{Region: "region1"},
	}
	var out structs.SingleNodeResponse

	// Register should succeed
	testutil.WaitForResult(func() (bool, error) {
		err := s1.RPC("Client.GetNode", &req, &out)
		if err != nil {
			return false, err
		}
		if out.Node == nil {
			return false, fmt.Errorf("missing reg")
		}
		return out.Node.ID == req.NodeID, nil
	}, func(err error) {
		t.Fatalf("err: %v", err)
	})
}