package e2e

import (
	"context"
	"errors"
	"fmt"
	"strings"
	"time"

	appsv1 "k8s.io/api/apps/v1"
	v1 "k8s.io/api/core/v1"
	apierrs "k8s.io/apimachinery/pkg/api/errors"
	metav1 "k8s.io/apimachinery/pkg/apis/meta/v1"
	"k8s.io/apimachinery/pkg/util/wait"
	"k8s.io/client-go/kubernetes"
	"k8s.io/kubernetes/pkg/client/conditions"
	"k8s.io/kubernetes/test/e2e/framework"
	e2elog "k8s.io/kubernetes/test/e2e/framework/log"
)

// getDaemonSetLabelSelector returns labels of daemonset given name and namespace dynamically,
// needed since labels are not same for helm and non-helm deployments.
func getDaemonSetLabelSelector(f *framework.Framework, ns, daemonSetName string) (string, error) {
	ds, err := f.ClientSet.AppsV1().DaemonSets(ns).Get(context.TODO(), daemonSetName, metav1.GetOptions{})
	if err != nil {
		e2elog.Logf("Error getting daemonsets with name %s in namespace %s", daemonSetName, ns)

		return "", err
	}
	s, err := metav1.LabelSelectorAsSelector(ds.Spec.Selector)
	if err != nil {
		e2elog.Logf("Error parsing %s daemonset selector in namespace %s", daemonSetName, ns)

		return "", err
	}
	e2elog.Logf("LabelSelector for %s daemonsets in namespace %s: %s", daemonSetName, ns, s.String())

	return s.String(), nil
}

func waitForDaemonSets(name, ns string, c kubernetes.Interface, t int) error {
	timeout := time.Duration(t) * time.Minute
	start := time.Now()
	e2elog.Logf("Waiting up to %v for all daemonsets in namespace '%s' to start", timeout, ns)

	return wait.PollImmediate(poll, timeout, func() (bool, error) {
		ds, err := c.AppsV1().DaemonSets(ns).Get(context.TODO(), name, metav1.GetOptions{})
		if err != nil {
			e2elog.Logf("Error getting daemonsets in namespace: '%s': %v", ns, err)
			if strings.Contains(err.Error(), "not found") {
				return false, nil
			}
			if isRetryableAPIError(err) {
				return false, nil
			}

			return false, err
		}
		dNum := ds.Status.DesiredNumberScheduled
		ready := ds.Status.NumberReady
		e2elog.Logf(
			"%d / %d pods ready in namespace '%s' in daemonset '%s' (%d seconds elapsed)",
			ready,
			dNum,
			ns,
			ds.ObjectMeta.Name,
			int(time.Since(start).Seconds()))
		if ready != dNum {
			return false, nil
		}

		return true, nil
	})
}

// Waits for the deployment to complete.

func waitForDeploymentComplete(name, ns string, c kubernetes.Interface, t int) error {
	var (
		deployment *appsv1.Deployment
		reason     string
		err        error
	)
	timeout := time.Duration(t) * time.Minute
	err = wait.PollImmediate(poll, timeout, func() (bool, error) {
		deployment, err = c.AppsV1().Deployments(ns).Get(context.TODO(), name, metav1.GetOptions{})
		if err != nil {
			if isRetryableAPIError(err) {
				return false, nil
			}
			e2elog.Logf("deployment error: %v", err)

			return false, err
		}

		// TODO need to check rolling update

		// When the deployment status and its underlying resources reach the
		// desired state, we're done
		if deployment.Status.Replicas == deployment.Status.ReadyReplicas {
			return true, nil
		}
		e2elog.Logf(
			"deployment status: expected replica count %d running replica count %d",
			deployment.Status.Replicas,
			deployment.Status.ReadyReplicas)
		reason = fmt.Sprintf("deployment status: %#v", deployment.Status.String())

		return false, nil
	})

	if errors.Is(err, wait.ErrWaitTimeout) {
		err = fmt.Errorf("%s", reason)
	}
	if err != nil {
		return fmt.Errorf("error waiting for deployment %q status to match expectation: %w", name, err)
	}

	return nil
}

func findPodAndContainerName(f *framework.Framework, ns, cn string, opt *metav1.ListOptions) (string, string, error) {
	podList, err := f.PodClientNS(ns).List(context.TODO(), *opt)
	if err != nil {
		return "", "", err
	}

	if len(podList.Items) == 0 {
		return "", "", errors.New("podlist is empty")
	}

	if cn != "" {
		for i := range podList.Items {
			for j := range podList.Items[i].Spec.Containers {
				if podList.Items[i].Spec.Containers[j].Name == cn {
					return podList.Items[i].Name, cn, nil
				}
			}
		}

		return "", "", errors.New("container name not found")
	}

	return podList.Items[0].Name, podList.Items[0].Spec.Containers[0].Name, nil
}

func getCommandInPodOpts(
	f *framework.Framework,
	c, ns, cn string,
	opt *metav1.ListOptions) (framework.ExecOptions, error) {
	cmd := []string{"/bin/sh", "-c", c}
	pName, cName, err := findPodAndContainerName(f, ns, cn, opt)
	if err != nil {
		return framework.ExecOptions{}, err
	}

	return framework.ExecOptions{
		Command:            cmd,
		PodName:            pName,
		Namespace:          ns,
		ContainerName:      cName,
		Stdin:              nil,
		CaptureStdout:      true,
		CaptureStderr:      true,
		PreserveWhitespace: true,
	}, nil
}

// execCommandInDaemonsetPod executes commands inside given container of a daemonset pod on a particular node.
func execCommandInDaemonsetPod(
	f *framework.Framework,
	c, daemonsetName, nodeName, containerName, ns string) (string, string, error) {
	selector, err := getDaemonSetLabelSelector(f, ns, daemonsetName)
	if err != nil {
		return "", "", err
	}

	opt := &metav1.ListOptions{
		LabelSelector: selector,
	}
	pods, err := listPods(f, ns, opt)
	if err != nil {
		return "", "", err
	}

	podName := ""
	for i := range pods {
		if pods[i].Spec.NodeName == nodeName {
			podName = pods[i].Name
		}
	}
	if podName == "" {
		return "", "", fmt.Errorf("%s daemonset pod on node %s in namespace %s not found", daemonsetName, nodeName, ns)
	}

	cmd := []string{"/bin/sh", "-c", c}
	podOpt := framework.ExecOptions{
		Command:       cmd,
		Namespace:     ns,
		PodName:       podName,
		ContainerName: containerName,
		CaptureStdout: true,
		CaptureStderr: true,
	}

	return f.ExecWithOptions(podOpt)
}

// listPods returns slice of pods matching given ListOptions and namespace.
func listPods(f *framework.Framework, ns string, opt *metav1.ListOptions) ([]v1.Pod, error) {
	podList, err := f.PodClientNS(ns).List(context.TODO(), *opt)
	if len(podList.Items) == 0 {
		return podList.Items, fmt.Errorf("podlist for label '%s' in namespace %s is empty", opt.LabelSelector, ns)
	}

	return podList.Items, err
}

func execCommandInPod(f *framework.Framework, c, ns string, opt *metav1.ListOptions) (string, string, error) {
	podOpt, err := getCommandInPodOpts(f, c, ns, "", opt)
	if err != nil {
		return "", "", err
	}
	stdOut, stdErr, err := f.ExecWithOptions(podOpt)
	if stdErr != "" {
		e2elog.Logf("stdErr occurred: %v", stdErr)
	}

	return stdOut, stdErr, err
}

func execCommandInContainer(
	f *framework.Framework, c, ns, cn string, opt *metav1.ListOptions) (string, string, error) {
	podOpt, err := getCommandInPodOpts(f, c, ns, cn, opt)
	if err != nil {
		return "", "", err
	}
	stdOut, stdErr, err := f.ExecWithOptions(podOpt)
	if stdErr != "" {
		e2elog.Logf("stdErr occurred: %v", stdErr)
	}

	return stdOut, stdErr, err
}

func execCommandInToolBoxPod(f *framework.Framework, c, ns string) (string, string, error) {
	opt := &metav1.ListOptions{
		LabelSelector: rookToolBoxPodLabel,
	}
	podOpt, err := getCommandInPodOpts(f, c, ns, "", opt)
	if err != nil {
		return "", "", err
	}
	stdOut, stdErr, err := f.ExecWithOptions(podOpt)
	if stdErr != "" {
		e2elog.Logf("stdErr occurred: %v", stdErr)
	}

	return stdOut, stdErr, err
}

func execCommandInPodAndAllowFail(f *framework.Framework, c, ns string, opt *metav1.ListOptions) (string, string) {
	podOpt, err := getCommandInPodOpts(f, c, ns, "", opt)
	if err != nil {
		return "", err.Error()
	}
	stdOut, stdErr, err := f.ExecWithOptions(podOpt)
	if err != nil {
		e2elog.Logf("command %s failed: %v", c, err)
	}

	return stdOut, stdErr
}

func loadApp(path string) (*v1.Pod, error) {
	app := v1.Pod{}
	if err := unmarshal(path, &app); err != nil {
		return nil, err
	}
	for i := range app.Spec.Containers {
		app.Spec.Containers[i].ImagePullPolicy = v1.PullIfNotPresent
	}

	return &app, nil
}

func createApp(c kubernetes.Interface, app *v1.Pod, timeout int) error {
	_, err := c.CoreV1().Pods(app.Namespace).Create(context.TODO(), app, metav1.CreateOptions{})
	if err != nil {
		return fmt.Errorf("failed to create app: %w", err)
	}

	return waitForPodInRunningState(app.Name, app.Namespace, c, timeout, noError)
}

func createAppErr(c kubernetes.Interface, app *v1.Pod, timeout int, errString string) error {
	_, err := c.CoreV1().Pods(app.Namespace).Create(context.TODO(), app, metav1.CreateOptions{})
	if err != nil {
		return err
	}

	return waitForPodInRunningState(app.Name, app.Namespace, c, timeout, errString)
}

func waitForPodInRunningState(name, ns string, c kubernetes.Interface, t int, expectedError string) error {
	timeout := time.Duration(t) * time.Minute
	start := time.Now()
	e2elog.Logf("Waiting up to %v to be in Running state", name)

	return wait.PollImmediate(poll, timeout, func() (bool, error) {
		pod, err := c.CoreV1().Pods(ns).Get(context.TODO(), name, metav1.GetOptions{})
		if err != nil {
			if isRetryableAPIError(err) {
				return false, nil
			}

			return false, fmt.Errorf("failed to get app: %w", err)
		}
		switch pod.Status.Phase {
		case v1.PodRunning:
			return true, nil
		case v1.PodFailed, v1.PodSucceeded:
			return false, conditions.ErrPodCompleted
		case v1.PodPending:
			if expectedError != "" {
				events, err := c.CoreV1().Events(ns).List(context.TODO(), metav1.ListOptions{
					FieldSelector: fmt.Sprintf("involvedObject.name=%s", name),
				})
				if err != nil {
					return false, err
				}
				if strings.Contains(events.String(), expectedError) {
					e2elog.Logf("Expected Error %q found successfully", expectedError)

					return true, err
				}
			}
		case v1.PodUnknown:
			e2elog.Logf(
				"%s app  is in %s phase expected to be in Running  state (%d seconds elapsed)",
				name,
				pod.Status.Phase,
				int(time.Since(start).Seconds()))
		}

		return false, nil
	})
}

func deletePod(name, ns string, c kubernetes.Interface, t int) error {
	timeout := time.Duration(t) * time.Minute
	err := c.CoreV1().Pods(ns).Delete(context.TODO(), name, metav1.DeleteOptions{})
	if err != nil {
		return fmt.Errorf("failed to delete app: %w", err)
	}
	start := time.Now()
	e2elog.Logf("Waiting for pod %v to be deleted", name)

	return wait.PollImmediate(poll, timeout, func() (bool, error) {
		_, err := c.CoreV1().Pods(ns).Get(context.TODO(), name, metav1.GetOptions{})
		if err != nil {
			if isRetryableAPIError(err) {
				return false, nil
			}
			if apierrs.IsNotFound(err) {
				return true, nil
			}
			e2elog.Logf("%s app  to be deleted (%d seconds elapsed)", name, int(time.Since(start).Seconds()))

			return false, fmt.Errorf("failed to get app: %w", err)
		}

		return false, nil
	})
}

func deletePodWithLabel(label, ns string, skipNotFound bool) error {
	err := retryKubectlArgs(
		ns,
		kubectlDelete,
		deployTimeout,
		"po",
		"-l",
		label,
		fmt.Sprintf("--ignore-not-found=%t", skipNotFound))
	if err != nil {
		e2elog.Logf("failed to delete pod %v", err)
	}

	return err
}

// calculateSHA512sum returns the sha512sum of a file inside a pod.
func calculateSHA512sum(f *framework.Framework, app *v1.Pod, filePath string, opt *metav1.ListOptions) (string, error) {
	cmd := fmt.Sprintf("sha512sum %s", filePath)
	sha512sumOut, stdErr, err := execCommandInPod(f, cmd, app.Namespace, opt)
	if err != nil {
		return "", err
	}
	if stdErr != "" {
		return "", fmt.Errorf("error: sha512sum could not be calculated %v", stdErr)
	}
	// extract checksum from sha512sum output.
	checkSum := strings.Split(sha512sumOut, "")[0]
	e2elog.Logf("Calculated checksum  %s", checkSum)

	return checkSum, nil
}