package client

import (
	"io/ioutil"
	"os"
	"path/filepath"
	"reflect"
	"testing"
	"time"

	"github.com/hashicorp/nomad/nomad/mock"
	"github.com/hashicorp/nomad/nomad/structs"
)

func TestDiffAllocs(t *testing.T) {
	t.Parallel()
	alloc1 := mock.Alloc() // Ignore
	alloc2 := mock.Alloc() // Update
	alloc2u := new(structs.Allocation)
	*alloc2u = *alloc2
	alloc2u.AllocModifyIndex += 1
	alloc3 := mock.Alloc() // Remove
	alloc4 := mock.Alloc() // Add

	exist := []*structs.Allocation{
		alloc1,
		alloc2,
		alloc3,
	}
	update := &allocUpdates{
		pulled: map[string]*structs.Allocation{
			alloc2u.ID: alloc2u,
			alloc4.ID:  alloc4,
		},
		filtered: map[string]struct{}{
			alloc1.ID: struct{}{},
		},
	}

	result := diffAllocs(exist, update)

	if len(result.ignore) != 1 || result.ignore[0] != alloc1 {
		t.Fatalf("Bad: %#v", result.ignore)
	}
	if len(result.added) != 1 || result.added[0] != alloc4 {
		t.Fatalf("Bad: %#v", result.added)
	}
	if len(result.removed) != 1 || result.removed[0] != alloc3 {
		t.Fatalf("Bad: %#v", result.removed)
	}
	if len(result.updated) != 1 {
		t.Fatalf("Bad: %#v", result.updated)
	}
	if result.updated[0].exist != alloc2 || result.updated[0].updated != alloc2u {
		t.Fatalf("Bad: %#v", result.updated)
	}
}

func TestRandomStagger(t *testing.T) {
	t.Parallel()
	intv := time.Minute
	for i := 0; i < 10; i++ {
		stagger := randomStagger(intv)
		if stagger < 0 || stagger >= intv {
			t.Fatalf("Bad: %v", stagger)
		}
	}
}

func TestShuffleStrings(t *testing.T) {
	t.Parallel()
	// Generate input
	inp := make([]string, 10)
	for idx := range inp {
		inp[idx] = structs.GenerateUUID()
	}

	// Copy the input
	orig := make([]string, len(inp))
	copy(orig, inp)

	// Shuffle
	shuffleStrings(inp)

	// Ensure order is not the same
	if reflect.DeepEqual(inp, orig) {
		t.Fatalf("shuffle failed")
	}
}

func TestPersistRestoreState(t *testing.T) {
	t.Parallel()
	dir, err := ioutil.TempDir("", "nomad")
	if err != nil {
		t.Fatalf("err: %s", err)
	}
	defer os.RemoveAll(dir)

	// Use a state path inside a non-existent directory. This
	// verifies that the directory is created properly.
	statePath := filepath.Join(dir, "subdir", "test-persist")

	type stateTest struct {
		Foo int
		Bar string
		Baz bool
	}
	state := stateTest{
		Foo: 42,
		Bar: "the quick brown fox",
		Baz: true,
	}

	err = persistState(statePath, &state)
	if err != nil {
		t.Fatalf("err: %v", err)
	}

	var out stateTest
	err = restoreState(statePath, &out)
	if err != nil {
		t.Fatalf("err: %v", err)
	}

	if !reflect.DeepEqual(state, out) {
		t.Fatalf("bad: %#v %#v", state, out)
	}
}