package render

import (
	"fmt"
	"strings"

	appsv1 "k8s.io/api/apps/v1"
	corev1 "k8s.io/api/core/v1"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/runtime"

	buildinfo "example.com/monok8s/pkg/buildinfo"
)

const cmmName = "cmm"

type CMMConf struct {
	Namespace        string
	Image            string
	ImagePullSecrets []string
	Labels           map[string]string
}

func RenderCMMDaemonSets(conf CMMConf) (string, error) {
	objs, err := buildCMMDaemonSetObjects(conf)
	if err != nil {
		return "", err
	}

	return renderObjects(objs)
}

func buildCMMDaemonSetObjects(conf CMMConf) ([]runtime.Object, error) {
	if strings.TrimSpace(conf.Namespace) == "" {
		return nil, fmt.Errorf("namespace is required")
	}

	conf.Labels = map[string]string{
		"app.kubernetes.io/name":       cmmName,
		"app.kubernetes.io/component":  "hardware-offload",
		"app.kubernetes.io/part-of":    "monok8s",
		"app.kubernetes.io/managed-by": "monok8s",
	}

	return []runtime.Object{
		buildCMMServiceAccount(conf),
		buildCMMDaemonSet(conf),
	}, nil
}

func buildCMMServiceAccount(conf CMMConf) *corev1.ServiceAccount {
	return &corev1.ServiceAccount{
		TypeMeta: metav1.TypeMeta{
			APIVersion: "v1",
			Kind:       "ServiceAccount",
		},
		ObjectMeta: metav1.ObjectMeta{
			Name:      cmmName,
			Namespace: conf.Namespace,
			Labels:    copyStringMap(conf.Labels),
		},
	}
}

func buildCMMDaemonSet(conf CMMConf) *appsv1.DaemonSet {
	privileged := true
	dsLabels := map[string]string{
		"app.kubernetes.io/name":       cmmName,
		"app.kubernetes.io/component":  "hardware-offload",
		"app.kubernetes.io/part-of":    "monok8s",
		"app.kubernetes.io/managed-by": "monok8s",
	}

	image, pullPolicy := cmmImage(conf)

	return &appsv1.DaemonSet{
		TypeMeta: metav1.TypeMeta{
			APIVersion: "apps/v1",
			Kind:       "DaemonSet",
		},
		ObjectMeta: metav1.ObjectMeta{
			Name:      cmmName,
			Namespace: conf.Namespace,
			Labels:    copyStringMap(conf.Labels),
		},
		Spec: appsv1.DaemonSetSpec{
			Selector: &metav1.LabelSelector{
				MatchLabels: map[string]string{
					"app.kubernetes.io/name": cmmName,
				},
			},
			Template: corev1.PodTemplateSpec{
				ObjectMeta: metav1.ObjectMeta{
					Labels: dsLabels,
				},
				Spec: corev1.PodSpec{
					ServiceAccountName: cmmName,
					HostNetwork:        true,
					DNSPolicy:          corev1.DNSClusterFirstWithHostNet,
					ImagePullSecrets:   imagePullSecrets(conf.ImagePullSecrets),
					Tolerations: []corev1.Toleration{
						{Operator: corev1.TolerationOpExists},
					},
					InitContainers: []corev1.Container{
						{
							Name:            "dpa-app",
							Image:           image,
							ImagePullPolicy: pullPolicy,
							Command:         []string{"/init_dpa.sh"},
							Env:             cdxEnv(),
							SecurityContext: &corev1.SecurityContext{
								Privileged: &privileged,
							},
							VolumeMounts: append(
								[]corev1.VolumeMount{
									{
										Name:      "host-run-cmm",
										MountPath: "/host/run/monok8s/cmm",
									},
								},
								cdxVolumeMounts()...,
							),
						},
					},
					Containers: []corev1.Container{
						{
							Name:            cmmName,
							Image:           image,
							ImagePullPolicy: pullPolicy,
							Env:             cmmEnv(),
							SecurityContext: &corev1.SecurityContext{
								Privileged: &privileged,
							},
							VolumeMounts: cdxVolumeMounts(),
						},
					},
					Volumes: cmmVolumes(),
					NodeSelector: map[string]string{
						"node.kubernetes.io/instance-type": "mono-gateway",
					},
				},
			},
		},
	}
}

func cdxEnv() []corev1.EnvVar {
	return []corev1.EnvVar{
		{
			Name:  "CDX_CFG_FILE",
			Value: "/etc/dpa/cdx_cfg.xml",
		},
		{
			Name:  "CDX_PCD_FILE",
			Value: "/etc/dpa/cdx_pcd.xml",
		},
		{
			Name:  "CDX_PDL_FILE",
			Value: "/etc/fmc/config/hxs_pdl_v3.xml",
		},
		{
			Name:  "CDX_SP_FILE",
			Value: "/etc/dpa/cdx_sp.xml",
		},
	}
}

func cmmEnv() []corev1.EnvVar {
	return []corev1.EnvVar{
		{
			Name:  "CMM_CONFIG",
			Value: "/etc/cmm/cmm.conf",
		},
		{
			Name:  "CMM_MAX_CONNECTIONS",
			Value: "131072",
		},
	}
}

func cdxVolumeMounts() []corev1.VolumeMount {
	return []corev1.VolumeMount{
		{
			Name:      "cdx-ctrl",
			MountPath: "/dev/cdx_ctrl",
		},
	}
}

func cmmVolumes() []corev1.Volume {
	return []corev1.Volume{
		{
			Name: "cdx-ctrl",
			VolumeSource: corev1.VolumeSource{
				HostPath: &corev1.HostPathVolumeSource{
					Path: "/dev/cdx_ctrl",
					Type: hostPathType(corev1.HostPathCharDev),
				},
			},
		},
		{
			Name: "host-run-cmm",
			VolumeSource: corev1.VolumeSource{
				HostPath: &corev1.HostPathVolumeSource{
					Path: "/run/monok8s/cmm",
					Type: hostPathType(corev1.HostPathDirectoryOrCreate),
				},
			},
		},
	}
}

func cmmImage(conf CMMConf) (string, corev1.PullPolicy) {
	if conf.Image != "" {
		return conf.Image, corev1.PullIfNotPresent
	}

	return fmt.Sprintf("localhost/monok8s/cmm:%s", buildinfo.Version), corev1.PullNever
}