/*
 * Copyright 2018 Intel Corporation, Inc
 * Copyright © 2021 Samsung Electronics
 *
 * 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 app

import (
	"log"
	"strconv"
	"strings"

	"github.com/onap/multicloud-k8s/src/k8splugin/internal/helm"

	pkgerrors "github.com/pkg/errors"
)

// Config contains the parameters needed for configuration
type Config struct {
	ConfigName   string                 `json:"config-name"`
	TemplateName string                 `json:"template-name"`
	Description  string                 `json:"description"`
	Values       map[string]interface{} `json:"values"`
}

//ConfigResult output for Create, Update and delete
type ConfigResult struct {
	InstanceName      string `json:"instance-id"`
	DefinitionName    string `json:"rb-name"`
	DefinitionVersion string `json:"rb-version"`
	ProfileName       string `json:"profile-name"`
	ConfigName        string `json:"config-name"`
	TemplateName      string `json:"template-name"`
	ConfigVersion     uint   `json:"config-version"`
}

//ConfigRollback input
type ConfigRollback struct {
	AnyOf struct {
		ConfigVersion string `json:"config-version,omitempty"`
		ConfigTag     string `json:"config-tag,omitempty"`
	} `json:"anyOf"`
}

//ConfigTagit for Tagging configurations
type ConfigTagit struct {
	TagName string `json:"tag-name"`
}

// ConfigManager is an interface exposes the config functionality
type ConfigManager interface {
	Create(instanceID string, p Config) (ConfigResult, error)
	Get(instanceID, configName string) (Config, error)
	List(instanceID string) ([]Config, error)
	Help() map[string]string
	Update(instanceID, configName string, p Config) (ConfigResult, error)
	Delete(instanceID, configName string) (ConfigResult, error)
	DeleteAll(instanceID, configName string) error
	Rollback(instanceID string, configName string, p ConfigRollback) error
	Cleanup(instanceID string) error
	Tagit(instanceID string, configName string, p ConfigTagit) error
}

// ConfigClient implements the ConfigManager
// It will also be used to maintain some localized state
type ConfigClient struct {
	tagTag string
}

// NewConfigClient returns an instance of the ConfigClient
// which implements the ConfigManager
func NewConfigClient() *ConfigClient {
	return &ConfigClient{
		tagTag: "tag",
	}
}

// Help returns some information on how to create the content
// for the config in the form of html formatted page
func (v *ConfigClient) Help() map[string]string {
	ret := make(map[string]string)

	return ret
}

// Create an entry for the config in the database
func (v *ConfigClient) Create(instanceID string, p Config) (ConfigResult, error) {
	log.Printf("[Config Create] Instance %s", instanceID)
	// Check required fields
	if p.ConfigName == "" || p.TemplateName == "" || len(p.Values) == 0 {
		return ConfigResult{}, pkgerrors.New("Incomplete Configuration Provided")
	}
	// Resolving rbName, Version, etc. not to break response
	rbName, rbVersion, profileName, _, err := resolveModelFromInstance(instanceID)
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Retrieving model info")
	}
	cs := ConfigStore{
		instanceID: instanceID,
		configName: p.ConfigName,
	}
	_, err = cs.getConfig()
	if err == nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Create Error - Config exists")
	} else {
		if strings.Contains(err.Error(), "Key doesn't exist") == false {
			return ConfigResult{}, pkgerrors.Wrap(err, "Create Error")
		}
	}
	lock, profileChannel := getProfileData(instanceID)
	// Acquire per profile Mutex
	lock.Lock()
	defer lock.Unlock()
	var appliedResources ([]helm.KubernetesResource)
	appliedResources, err = applyConfig(instanceID, p, profileChannel, "POST", nil)
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Apply Config failed")
	}
	log.Printf("POST result: %s", appliedResources)
	// Create Config DB Entry
	err = cs.createConfig(p)
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Create Config DB Entry")
	}
	// Create Version Entry in DB for Config
	cvs := ConfigVersionStore{
		instanceID: instanceID,
		configName: p.ConfigName,
	}
	version, err := cvs.createConfigVersion(p, Config{}, "POST", appliedResources)
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Create Config Version DB Entry")
	}

	// Create Result structure
	cfgRes := ConfigResult{
		InstanceName:      instanceID,
		DefinitionName:    rbName,
		DefinitionVersion: rbVersion,
		ProfileName:       profileName,
		ConfigName:        p.ConfigName,
		TemplateName:      p.TemplateName,
		ConfigVersion:     version,
	}
	return cfgRes, nil
}

// Update an entry for the config in the database
func (v *ConfigClient) Update(instanceID, configName string, p Config) (ConfigResult, error) {
	log.Printf("[Config Update] Instance %s Config %s", instanceID, configName)
	// Check required fields
	if len(p.Values) == 0 {
		return ConfigResult{}, pkgerrors.New("Incomplete Configuration Provided")
	}
	// Resolving rbName, Version, etc. not to break response
	rbName, rbVersion, profileName, _, err := resolveModelFromInstance(instanceID)
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Retrieving model info")
	}
	// Check if Config exists
	cs := ConfigStore{
		instanceID: instanceID,
		configName: configName,
	}
	_, err = cs.getConfig()
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Update Error - Config doesn't exist")
	}
	lock, profileChannel := getProfileData(instanceID)
	// Acquire per profile Mutex
	lock.Lock()
	defer lock.Unlock()
	var appliedResources ([]helm.KubernetesResource)
	appliedResources, err = applyConfig(instanceID, p, profileChannel, "PUT", nil)
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Apply Config  failed")
	}
	log.Printf("PUT result: %s", appliedResources)
	// Update Config DB Entry
	configPrev, err := cs.updateConfig(p)
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Update Config DB Entry")
	}
	// Create Version Entry in DB for Config
	cvs := ConfigVersionStore{
		instanceID: instanceID,
		configName: configName,
	}
	version, err := cvs.createConfigVersion(p, configPrev, "PUT", appliedResources)
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Create Config Version DB Entry")
	}

	// Create Result structure
	cfgRes := ConfigResult{
		InstanceName:      instanceID,
		DefinitionName:    rbName,
		DefinitionVersion: rbVersion,
		ProfileName:       profileName,
		ConfigName:        p.ConfigName,
		TemplateName:      p.TemplateName,
		ConfigVersion:     version,
	}
	return cfgRes, nil
}

// Get config entry in the database
func (v *ConfigClient) Get(instanceID, configName string) (Config, error) {

	// Acquire per profile Mutex
	lock, _ := getProfileData(instanceID)
	lock.Lock()
	defer lock.Unlock()
	// Read Config DB
	cs := ConfigStore{
		instanceID: instanceID,
		configName: configName,
	}
	cfg, err := cs.getConfig()
	if err != nil {
		return Config{}, pkgerrors.Wrap(err, "Get Config DB Entry")
	}
	return cfg, nil
}

// List config entry in the database
func (v *ConfigClient) List(instanceID string) ([]Config, error) {

	// Acquire per profile Mutex
	lock, _ := getProfileData(instanceID)
	lock.Lock()
	defer lock.Unlock()
	// Read Config DB
	cs := ConfigStore{
		instanceID: instanceID,
	}
	cfg, err := cs.getConfigList()
	if err != nil {
		return []Config{}, pkgerrors.Wrap(err, "Get Config DB Entry")
	}
	return cfg, nil
}

// Delete the Config from database
func (v *ConfigClient) DeleteAll(instanceID, configName string) error {
	log.Printf("[Config Delete All] Instance %s Config %s", instanceID, configName)
	// Check if Config exists
	cs := ConfigStore{
		instanceID: instanceID,
		configName: configName,
	}
	_, err := cs.getConfig()
	if err != nil {
		return pkgerrors.Wrap(err, "Update Error - Config doesn't exist")
	}
	// Get Version Entry in DB for Config
	cvs := ConfigVersionStore{
		instanceID: instanceID,
		configName: configName,
	}
	currentVersion, err := cvs.getCurrentVersion(configName)
	if err != nil {
		return pkgerrors.Wrap(err, "Current version get failed")
	}
	_, _, action, _, err := cvs.getConfigVersion(configName, currentVersion)
	if err != nil {
		return pkgerrors.Wrap(err, "Config version get failed")
	}

	if action != "DELETE" {
		_, err = v.Delete(instanceID, configName)
		if err != nil {
			return pkgerrors.Wrap(err, "Config  DELETE version failed")
		}
	}
	// Delete Config from DB
	_, err = cs.deleteConfig()
	if err != nil {
		return pkgerrors.Wrap(err, "Delete Config DB Entry")
	}
	cvs.cleanupIstanceTags(configName)
	return nil
}

// Apply update with delete operation
func (v *ConfigClient) Delete(instanceID, configName string) (ConfigResult, error) {
	log.Printf("[Config Delete] Instance %s Config %s", instanceID, configName)
	// Resolving rbName, Version, etc. not to break response
	rbName, rbVersion, profileName, _, err := resolveModelFromInstance(instanceID)
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Retrieving model info")
	}
	// Check if Config exists
	cs := ConfigStore{
		instanceID: instanceID,
		configName: configName,
	}
	p, err := cs.getConfig()
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Delete Error - Config doesn't exist")
	}
	lock, profileChannel := getProfileData(instanceID)
	// Acquire per profile Mutex
	lock.Lock()
	defer lock.Unlock()
	// Create Version Entry in DB for Config
	cvs := ConfigVersionStore{
		instanceID: instanceID,
		configName: configName,
	}
	currentVersion, err := cvs.getCurrentVersion(configName)
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Current version get failed")
	}
	_, _, _, resources, err := cvs.getConfigVersion(configName, currentVersion)
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Config version get failed")
	}

	_, err = applyConfig(instanceID, p, profileChannel, "DELETE", resources)
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Apply Config  failed")
	}
	log.Printf("DELETE resources: [%s]", resources)
	// Update Config from DB
	configPrev, err := cs.updateConfig(p)
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Update Config DB Entry")
	}
	version, err := cvs.createConfigVersion(p, configPrev, "DELETE", []helm.KubernetesResource{})
	if err != nil {
		return ConfigResult{}, pkgerrors.Wrap(err, "Create Delete Config Version DB Entry")
	}

	// Create Result structure
	cfgRes := ConfigResult{
		InstanceName:      instanceID,
		DefinitionName:    rbName,
		DefinitionVersion: rbVersion,
		ProfileName:       profileName,
		ConfigName:        configName,
		TemplateName:      configPrev.TemplateName,
		ConfigVersion:     version,
	}
	return cfgRes, nil
}

// Rollback starts from current version and rollbacks to the version desired
func (v *ConfigClient) Rollback(instanceID string, configName string, rback ConfigRollback) error {
	log.Printf("[Config Rollback] Instance %s Config %s", instanceID, configName)
	var reqVersion string
	var err error

	if rback.AnyOf.ConfigTag != "" {
		reqVersion, err = v.GetTagVersion(instanceID, configName, rback.AnyOf.ConfigTag)
		if err != nil {
			return pkgerrors.Wrap(err, "Rollback Invalid tag")
		}
	} else if rback.AnyOf.ConfigVersion != "" {
		reqVersion = rback.AnyOf.ConfigVersion
	} else {
		return pkgerrors.Errorf("No valid Index for Rollback")
	}

	index, err := strconv.Atoi(reqVersion)
	if err != nil {
		return pkgerrors.Wrap(err, "Rollback Invalid Index")
	}
	rollbackIndex := uint(index)

	lock, profileChannel := getProfileData(instanceID)
	// Acquire per profile Mutex
	lock.Lock()
	defer lock.Unlock()

	cvs := ConfigVersionStore{
		instanceID: instanceID,
		configName: configName,
	}
	currentVersion, err := cvs.getCurrentVersion(configName)
	if err != nil {
		return pkgerrors.Wrap(err, "Rollback Get Current Config Version ")
	}

	if rollbackIndex < 1 && rollbackIndex >= currentVersion {
		return pkgerrors.Wrap(err, "Rollback Invalid Config Version")
	}

	//Rollback all the intermettinent configurations
	for i := currentVersion; i > rollbackIndex; i-- {
		configNew, configPrev, _, resources, err := cvs.getConfigVersion(configName, i)
		if err != nil {
			return pkgerrors.Wrap(err, "Rollback Get Config Version")
		}
		_, _, prevAction, _, err := cvs.getConfigVersion(configName, i-1)
		if err != nil {
			return pkgerrors.Wrap(err, "Rollback Get Prev Config Version")
		}
		cs := ConfigStore{
			instanceID: instanceID,
			configName: configNew.ConfigName,
		}
		if prevAction != "DELETE" {
			appliedResources, err := applyConfig(instanceID, configPrev, profileChannel, prevAction, nil)
			if err != nil {
				return pkgerrors.Wrap(err, "Apply Config  failed")
			}
			log.Printf("%s result: %s", prevAction, appliedResources)
			_, err = cs.updateConfig(configPrev)
			if err != nil {
				return pkgerrors.Wrap(err, "Update Config DB Entry")
			}
		} else {
			// POST is always preceeded by Config not existing
			_, err := applyConfig(instanceID, configNew, profileChannel, prevAction, resources)
			if err != nil {
				return pkgerrors.Wrap(err, "Delete Config  failed")
			}
			log.Printf("DELETE resources: %s", resources)
			_, err = cs.updateConfig(configPrev)
			if err != nil {
				return pkgerrors.Wrap(err, "Update Config DB Entry")
			}
		}
	}
	for i := currentVersion; i > rollbackIndex; i-- {
		// Delete rolled back items
		err = cvs.deleteConfigVersion(configName)
		if err != nil {
			return pkgerrors.Wrap(err, "Delete Config Version ")
		}
	}
	return nil
}

// Tagit tags the current version with the tag provided
func (v *ConfigClient) Tagit(instanceID string, configName string, tag ConfigTagit) error {
	log.Printf("[Config Tag It] Instance %s Config %s", instanceID, configName)
	lock, _ := getProfileData(instanceID)
	// Acquire per profile Mutex
	lock.Lock()
	defer lock.Unlock()

	cvs := ConfigVersionStore{
		instanceID: instanceID,
		configName: configName,
	}
	err := cvs.tagCurrentVersion(configName, tag.TagName)
	if err != nil {
		return pkgerrors.Wrap(err, "Tag of current version failed")
	}
	return nil
}

// GetTagVersion returns the version associated with the tag
func (v *ConfigClient) GetTagVersion(instanceID, configName string, tagName string) (string, error) {
	log.Printf("[Config Get Tag Version] Instance %s Config %s", instanceID, configName)
	cvs := ConfigVersionStore{
		instanceID: instanceID,
		configName: configName,
	}
	value, err := cvs.getTagVersion(configName, tagName)
	if err != nil {
		return "", pkgerrors.Wrap(err, "Tag of current version failed")
	}

	return value, nil
}

// Cleanup version used only when instance is being deleted. We do not pass errors and we try to delete data
func (v *ConfigClient) Cleanup(instanceID string) error {
	log.Printf("[Config Cleanup] Instance %s", instanceID)
	configs, err := v.List(instanceID)

	if err != nil {
		return pkgerrors.Wrap(err, "Retrieving active config list info")
	}

	for _, config := range configs {
		err = v.DeleteAll(instanceID, config.ConfigName)
		if err != nil {
			log.Printf("Config %s delete failed: %s", config.ConfigName, err.Error())
		}
	}

	removeProfileData(instanceID)

	return nil
}

// ApplyAllConfig starts from first configuration version and applies all versions in sequence
func (v *ConfigClient) ApplyAllConfig(instanceID string, configName string) error {
	log.Printf("[Config Apply All] Instance %s Config %s", instanceID, configName)
	lock, profileChannel := getProfileData(instanceID)
	// Acquire per profile Mutex
	lock.Lock()
	defer lock.Unlock()

	cvs := ConfigVersionStore{
		instanceID: instanceID,
		configName: configName,
	}
	currentVersion, err := cvs.getCurrentVersion(configName)
	if err != nil {
		return pkgerrors.Wrap(err, "Get Current Config Version ")
	}
	if currentVersion < 1 {
		return pkgerrors.Wrap(err, "No Config Version to Apply")
	}
	//Apply all configurations
	var i uint
	for i = 1; i <= currentVersion; i++ {
		configNew, _, action, resources, err := cvs.getConfigVersion(configName, i)
		if err != nil {
			return pkgerrors.Wrap(err, "Get Config Version")
		}
		if action != "DELETE" {
			resources = nil
		}
		var appliedResources ([]helm.KubernetesResource)
		appliedResources, err = applyConfig(instanceID, configNew, profileChannel, action, resources)
		if err != nil {
			return pkgerrors.Wrap(err, "Apply Config  failed")
		}
		log.Printf("%s result: %s", action, appliedResources)
	}
	return nil
}