/*
Copyright 2016 The Rook Authors. All rights reserved.

Licensed under the Apache License, Version 2.0 (the "License");
you may not use this file except in compliance with the License.
You may obtain a copy of the License at

	http://www.apache.org/licenses/LICENSE-2.0

Unless required by applicable law or agreed to in writing, software
distributed under the License is distributed on an "AS IS" BASIS,
WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
See the License for the specific language governing permissions and
limitations under the License.
*/
package v1

import (
	"encoding/json"
	"testing"

	"github.com/stretchr/testify/assert"
	v1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/util/yaml"
)

func TestPlacementSpec(t *testing.T) {
	specYaml := []byte(`
nodeAffinity:
  requiredDuringSchedulingIgnoredDuringExecution:
    nodeSelectorTerms:
    - matchExpressions:
      - key: foo
        operator: In
        values:
          - bar
tolerations:
  - key: foo
    operator: Exists
topologySpreadConstraints:
  - maxSkew: 1
    topologyKey: zone
    whenUnsatisfiable: DoNotSchedule
    labelSelector:
      matchLabels:
        foo: bar`)
	// convert the raw spec yaml into JSON
	rawJSON, err := yaml.ToJSON(specYaml)
	assert.Nil(t, err)

	// unmarshal the JSON into a strongly typed placement spec object
	var placement Placement
	err = json.Unmarshal(rawJSON, &placement)
	assert.Nil(t, err)

	// the unmarshalled placement spec should equal the expected spec below
	expected := Placement{
		NodeAffinity: &v1.NodeAffinity{
			RequiredDuringSchedulingIgnoredDuringExecution: &v1.NodeSelector{
				NodeSelectorTerms: []v1.NodeSelectorTerm{
					{
						MatchExpressions: []v1.NodeSelectorRequirement{
							{
								Key:      "foo",
								Operator: v1.NodeSelectorOpIn,
								Values:   []string{"bar"},
							},
						},
					},
				},
			},
		},
		Tolerations: []v1.Toleration{
			{
				Key:      "foo",
				Operator: v1.TolerationOpExists,
			},
		},
		TopologySpreadConstraints: []v1.TopologySpreadConstraint{
			{
				MaxSkew:           1,
				TopologyKey:       "zone",
				WhenUnsatisfiable: "DoNotSchedule",
				LabelSelector: &metav1.LabelSelector{
					MatchLabels: map[string]string{"foo": "bar"},
				},
			},
		},
	}
	assert.Equal(t, expected, placement)
}

func TestMergeNodeAffinity(t *testing.T) {
	// affinity is nil
	p := Placement{}
	result := p.mergeNodeAffinity(nil)
	assert.Nil(t, result)

	// node affinity is only set on the placement and should remain unchanged
	p.NodeAffinity = placementTestGenerateNodeAffinity()
	result = p.mergeNodeAffinity(nil)
	assert.Equal(t, p.NodeAffinity, result)

	// preferred set, but required not set
	affinityToMerge := placementTestGenerateNodeAffinity()
	affinityToMerge.RequiredDuringSchedulingIgnoredDuringExecution = nil
	result = p.mergeNodeAffinity(affinityToMerge)
	assert.Equal(t, 2, len(result.PreferredDuringSchedulingIgnoredDuringExecution))
	assert.Equal(t, p.NodeAffinity.RequiredDuringSchedulingIgnoredDuringExecution, result.RequiredDuringSchedulingIgnoredDuringExecution)

	// preferred and required expressions set
	affinityToMerge = placementTestGenerateNodeAffinity()
	affinityToMerge.RequiredDuringSchedulingIgnoredDuringExecution.NodeSelectorTerms[0].MatchExpressions[0].Key = "baz"
	result = p.mergeNodeAffinity(affinityToMerge)
	assert.Equal(t, 2, len(result.PreferredDuringSchedulingIgnoredDuringExecution))
	assert.Equal(t, 2, len(result.RequiredDuringSchedulingIgnoredDuringExecution.NodeSelectorTerms[0].MatchExpressions))
	assert.Equal(t, "baz", result.RequiredDuringSchedulingIgnoredDuringExecution.NodeSelectorTerms[0].MatchExpressions[0].Key)
	assert.Equal(t, "foo", result.RequiredDuringSchedulingIgnoredDuringExecution.NodeSelectorTerms[0].MatchExpressions[1].Key)
}

func TestPlacementApplyToPodSpec(t *testing.T) {
	to := placementTestGetTolerations("foo", "bar")
	na := placementTestGenerateNodeAffinity()
	antiaffinity := placementAntiAffinity("v1")
	tc := placementTestGetTopologySpreadConstraints("zone")
	expected := &v1.PodSpec{
		Affinity:                  &v1.Affinity{NodeAffinity: na, PodAntiAffinity: antiaffinity},
		Tolerations:               to,
		TopologySpreadConstraints: tc,
	}

	var p Placement
	var ps *v1.PodSpec

	p = Placement{
		NodeAffinity:              na,
		Tolerations:               to,
		PodAntiAffinity:           antiaffinity,
		TopologySpreadConstraints: tc,
	}
	ps = &v1.PodSpec{}
	p.ApplyToPodSpec(ps)
	assert.Equal(t, expected, ps)
	assert.Equal(t, 1, len(ps.Affinity.PodAntiAffinity.PreferredDuringSchedulingIgnoredDuringExecution))

	// Appending some other antiaffinity to the pod spec should not alter the original placement antiaffinity
	otherAntiAffinity := placementAntiAffinity("v2")
	ps.Affinity.PodAntiAffinity.PreferredDuringSchedulingIgnoredDuringExecution = append(
		ps.Affinity.PodAntiAffinity.PreferredDuringSchedulingIgnoredDuringExecution,
		otherAntiAffinity.PreferredDuringSchedulingIgnoredDuringExecution...)
	assert.Equal(t, 1, len(antiaffinity.PreferredDuringSchedulingIgnoredDuringExecution))

	// partial update
	p = Placement{NodeAffinity: na, PodAntiAffinity: antiaffinity}
	ps = &v1.PodSpec{Tolerations: to, TopologySpreadConstraints: tc}
	p.ApplyToPodSpec(ps)
	assert.Equal(t, expected, ps)

	// overridden attributes
	p = Placement{
		NodeAffinity:              na,
		PodAntiAffinity:           antiaffinity,
		Tolerations:               to,
		TopologySpreadConstraints: tc,
	}
	ps = &v1.PodSpec{
		TopologySpreadConstraints: placementTestGetTopologySpreadConstraints("rack"),
	}
	p.ApplyToPodSpec(ps)
	assert.Equal(t, expected, ps)

	// The preferred affinity is merged from both sources to result in two node affinities
	p = Placement{NodeAffinity: na, PodAntiAffinity: antiaffinity}
	nap := placementTestGenerateNodeAffinity()
	nap.PreferredDuringSchedulingIgnoredDuringExecution[0].Weight = 5
	ps = &v1.PodSpec{
		Affinity:                  &v1.Affinity{NodeAffinity: nap},
		Tolerations:               to,
		TopologySpreadConstraints: tc,
	}
	p.ApplyToPodSpec(ps)
	assert.Equal(t, 2, len(ps.Affinity.NodeAffinity.PreferredDuringSchedulingIgnoredDuringExecution))

	p = Placement{NodeAffinity: na, PodAntiAffinity: antiaffinity}
	to = placementTestGetTolerations("foo", "bar")
	ps = &v1.PodSpec{
		Tolerations: to,
	}
	p.ApplyToPodSpec(ps)
	assert.Equal(t, 1, len(ps.Tolerations))
	p = Placement{Tolerations: to, NodeAffinity: na, PodAntiAffinity: antiaffinity}
	p.ApplyToPodSpec(ps)
	assert.Equal(t, 2, len(ps.Tolerations))
}

func TestPlacementMerge(t *testing.T) {
	to := placementTestGetTolerations("foo", "bar")
	na := placementTestGenerateNodeAffinity()
	tc := placementTestGetTopologySpreadConstraints("zone")

	var original, with, expected, merged Placement

	original = Placement{}
	with = Placement{Tolerations: to}
	expected = Placement{Tolerations: to}
	merged = original.Merge(with)
	assert.Equal(t, expected, merged)

	original = Placement{NodeAffinity: na}
	with = Placement{Tolerations: to}
	expected = Placement{NodeAffinity: na, Tolerations: to}
	merged = original.Merge(with)
	assert.Equal(t, expected, merged)

	original = Placement{}
	with = Placement{TopologySpreadConstraints: tc}
	expected = Placement{TopologySpreadConstraints: tc}
	merged = original.Merge(with)
	assert.Equal(t, expected, merged)

	original = Placement{
		Tolerations:               placementTestGetTolerations("bar", "baz"),
		TopologySpreadConstraints: placementTestGetTopologySpreadConstraints("rack"),
	}
	with = Placement{
		NodeAffinity:              na,
		Tolerations:               to,
		TopologySpreadConstraints: tc,
	}
	var ts int64 = 10
	expected = Placement{
		NodeAffinity: na,
		Tolerations: []v1.Toleration{
			{
				Key:               "bar",
				Operator:          v1.TolerationOpExists,
				Value:             "baz",
				Effect:            v1.TaintEffectNoSchedule,
				TolerationSeconds: &ts,
			},
			{
				Key:               "foo",
				Operator:          v1.TolerationOpExists,
				Value:             "bar",
				Effect:            v1.TaintEffectNoSchedule,
				TolerationSeconds: &ts,
			},
		},
		TopologySpreadConstraints: tc,
	}
	merged = original.Merge(with)
	assert.Equal(t, expected, merged)
}

func placementTestGetTolerations(key, value string) []v1.Toleration {
	var ts int64 = 10
	return []v1.Toleration{
		{
			Key:               key,
			Operator:          v1.TolerationOpExists,
			Value:             value,
			Effect:            v1.TaintEffectNoSchedule,
			TolerationSeconds: &ts,
		},
	}
}

func placementTestGetTopologySpreadConstraints(topologyKey string) []v1.TopologySpreadConstraint {
	return []v1.TopologySpreadConstraint{
		{
			MaxSkew:           1,
			TopologyKey:       topologyKey,
			WhenUnsatisfiable: "DoNotSchedule",
			LabelSelector: &metav1.LabelSelector{
				MatchLabels: map[string]string{"foo": "bar"},
			},
		},
	}
}

func placementAntiAffinity(value string) *v1.PodAntiAffinity {
	return &v1.PodAntiAffinity{
		PreferredDuringSchedulingIgnoredDuringExecution: []v1.WeightedPodAffinityTerm{
			{
				Weight: 50,
				PodAffinityTerm: v1.PodAffinityTerm{
					LabelSelector: &metav1.LabelSelector{
						MatchLabels: map[string]string{
							"app": value,
						},
					},
					TopologyKey: v1.LabelHostname,
				},
			},
		},
	}
}

func placementTestGenerateNodeAffinity() *v1.NodeAffinity {
	return &v1.NodeAffinity{
		RequiredDuringSchedulingIgnoredDuringExecution: &v1.NodeSelector{
			NodeSelectorTerms: []v1.NodeSelectorTerm{
				{
					MatchExpressions: []v1.NodeSelectorRequirement{
						{
							Key:      "foo",
							Operator: v1.NodeSelectorOpExists,
							Values:   []string{"bar"},
						},
					},
				},
			},
		},
		PreferredDuringSchedulingIgnoredDuringExecution: []v1.PreferredSchedulingTerm{
			{
				Weight: 10,
				Preference: v1.NodeSelectorTerm{
					MatchExpressions: []v1.NodeSelectorRequirement{
						{
							Key:      "foo",
							Operator: v1.NodeSelectorOpExists,
							Values:   []string{"bar"},
						},
					},
				},
			},
		},
	}
}

func TestMergeToleration(t *testing.T) {
	// placement is nil
	p := Placement{}
	result := p.mergeTolerations(nil)
	assert.Nil(t, result)

	placementToleration := []v1.Toleration{
		{
			Key:      "foo",
			Operator: v1.TolerationOpEqual,
		},
	}

	p.Tolerations = placementToleration
	result = p.mergeTolerations(nil)
	assert.Equal(t, p.Tolerations, result)

	newToleration := []v1.Toleration{
		{
			Key:      "new",
			Operator: v1.TolerationOpExists,
		},
	}

	result = p.mergeTolerations(newToleration)
	assert.Equal(t, 2, len(result))
	assert.Equal(t, placementToleration[0].Key, result[0].Key)
	assert.Equal(t, newToleration[0].Key, result[1].Key)
}