package thinclient

import (
	"context"
	"encoding/json"

	corev1 "k8s.io/api/core/v1"
	ctrl "sigs.k8s.io/controller-runtime"
	"sigs.k8s.io/controller-runtime/pkg/client"

	"edge-infra.dev/pkg/sds"
	"edge-infra.dev/pkg/sds/ien/k8s/controllers/nodeagent/config"
	"edge-infra.dev/pkg/sds/ien/k8s/controllers/nodeagent/plugins/thinclient/selector"
	"edge-infra.dev/pkg/sds/lib/os/file"
	"edge-infra.dev/pkg/sds/lib/os/passthrough"
)

var (
	configMapObjectType = "ConfigMap"

	thinclientConfigMapField = "config.json"
)

type Configuration struct {
	Selectors selector.Selectors `json:"selectors"`
}

type ConfigurationPlugin struct{}

func (thinclientPlugin ConfigurationPlugin) Reconcile(ctx context.Context, object client.Object, conf config.Config) error {
	log := ctrl.LoggerFrom(ctx)
	configMap, ok := object.(*corev1.ConfigMap)
	if !ok {
		return nil
	}

	if !isThinclientConfigurationConfigMap(configMap, conf) {
		return nil
	}

	selectors, err := getSelectorsFromThinclientConfiguration(configMap)
	if err != nil {
		log.Error(err, "failed to get selectors for object")
		return err
	}

	rootPath, err := conf.GetRootPath(ctx)
	if err != nil {
		log.Error(err, "failed to get host root path")
		return err
	}
	if err = updateTargetObjects(ctx, selectors, conf, file.New(), passthrough.New(rootPath)); err != nil {
		log.Error(err, "failed to update target objects for selectors")
		return err
	}
	return nil
}

func isThinclientConfigurationConfigMap(configMap *corev1.ConfigMap, cfg config.Config) bool {
	name := cfg.GetFlags().ThinclientConfigMap
	return configMap.GetNamespace() == sds.Namespace && name != nil && configMap.GetName() == *name
}

// Parse the JSON data into Selectors (list of Selector structs)
func getSelectorsFromThinclientConfiguration(thinclientConfiguration *corev1.ConfigMap) (selector.Selectors, error) {
	configJSON := thinclientConfiguration.Data[thinclientConfigMapField]
	config := &Configuration{}
	if err := json.Unmarshal([]byte(configJSON), config); err != nil {
		return nil, err
	}
	selectors := config.Selectors
	for idx, selector := range selectors {
		if selector.Type == "" {
			selectors[idx].Type = configMapObjectType
		}
	}
	return selectors, nil
}

func updateTargetObjects(ctx context.Context, selectors selector.Selectors, conf config.Config, fileHandler file.File, passthrough passthrough.Exec) error {
	for _, selector := range selectors {
		configObjects, err := selector.GetTargetConfigObjects(ctx, conf)
		if err != nil {
			return err
		}
		for _, configObject := range configObjects {
			if err = configObject.Update(selector.Directory, selector.Service, fileHandler, passthrough); err != nil {
				return err
			}
		}
	}
	return nil
}