package navtree

import (
	"encoding/json"
	"sort"
)

const (
	// These weights may be used by an extension to reliably place
	// itself in relation to a particular item in the menu. The weights
	// are negative to ensure that the default items are placed above
	// any items with default weight.

	WeightHome = (iota - 20) * 100
	WeightSavedItems
	WeightDashboard
	WeightExplore
	WeightAlerting
	WeightAlertsAndIncidents
	WeightTestingAndSynthetics
	WeightMonitoring
	WeightInfrastructure
	WeightApplication
	WeightFrontend
	WeightAsserts
	WeightDataConnections
	WeightApps
	WeightPlugin
	WeightConfig
	WeightProfile
	WeightHelp
)

const (
	NavIDRoot                 = "root"
	NavIDDashboards           = "dashboards/browse"
	NavIDExplore              = "explore"
	NavIDCfg                  = "cfg" // NavIDCfg is the id for org configuration navigation node
	NavIDAlertsAndIncidents   = "alerts-and-incidents"
	NavIDTestingAndSynthetics = "testing-and-synthetics"
	NavIDAlerting             = "alerting"
	NavIDMonitoring           = "monitoring"
	NavIDInfrastructure       = "infrastructure"
	NavIDFrontend             = "frontend"
	NavIDReporting            = "reports"
	NavIDApps                 = "apps"
	NavIDCfgGeneral           = "cfg/general"
	NavIDCfgPlugins           = "cfg/plugins"
	NavIDCfgAccess            = "cfg/access"
)

type NavLink struct {
	Id             string     `json:"id,omitempty"`
	Text           string     `json:"text"`
	SubTitle       string     `json:"subTitle,omitempty"`
	Icon           string     `json:"icon,omitempty"` // Available icons can be browsed in Storybook: https://developers.grafana.com/ui/latest/index.html?path=/story/docs-overview-icon--icons-overview
	Img            string     `json:"img,omitempty"`
	Url            string     `json:"url,omitempty"`
	Target         string     `json:"target,omitempty"`
	SortWeight     int64      `json:"sortWeight,omitempty"`
	HideFromTabs   bool       `json:"hideFromTabs,omitempty"`
	RoundIcon      bool       `json:"roundIcon,omitempty"`
	IsSection      bool       `json:"isSection,omitempty"`
	Children       []*NavLink `json:"children,omitempty"`
	HighlightText  string     `json:"highlightText,omitempty"`
	HighlightID    string     `json:"highlightId,omitempty"`
	EmptyMessageId string     `json:"emptyMessageId,omitempty"`
	PluginID       string     `json:"pluginId,omitempty"` // (Optional) The ID of the plugin that registered nav link (e.g. as a standalone plugin page)
	IsCreateAction bool       `json:"isCreateAction,omitempty"`
	Keywords       []string   `json:"keywords,omitempty"`
}

func (node *NavLink) Sort() {
	Sort(node.Children)
}

type NavTreeRoot struct {
	Children []*NavLink
}

func (root *NavTreeRoot) AddSection(node *NavLink) {
	root.Children = append(root.Children, node)
}

func (root *NavTreeRoot) RemoveSection(node *NavLink) {
	var result []*NavLink

	for _, child := range root.Children {
		if child != node {
			result = append(result, child)
		}
	}

	root.Children = result
}

func (root *NavTreeRoot) FindById(id string) *NavLink {
	return FindById(root.Children, id)
}
func (root *NavTreeRoot) FindByURL(url string) *NavLink {
	return FindByURL(root.Children, url)
}
func (root *NavTreeRoot) Sort() {
	Sort(root.Children)
}

func (root *NavTreeRoot) MarshalJSON() ([]byte, error) {
	return json.Marshal(root.Children)
}

func Sort(nodes []*NavLink) {
	sort.SliceStable(nodes, func(i, j int) bool {
		iw := nodes[i].SortWeight
		if iw == 0 {
			iw = int64(i) + 1
		}
		jw := nodes[j].SortWeight
		if jw == 0 {
			jw = int64(j) + 1
		}

		return iw < jw
	})

	for _, child := range nodes {
		child.Sort()
	}
}

func (root *NavTreeRoot) ApplyHelpVersion(version string) {
	helpNode := root.FindById("help")

	if helpNode != nil {
		helpNode.SubTitle = version
	}
}

func (root *NavTreeRoot) ApplyAdminIA() {
	orgAdminNode := root.FindById(NavIDCfg)

	if orgAdminNode != nil {
		adminNodeLinks := []*NavLink{}

		generalNodeLinks := []*NavLink{}
		generalNodeLinks = AppendIfNotNil(generalNodeLinks, root.FindById("upgrading")) // TODO does this even exist
		generalNodeLinks = AppendIfNotNil(generalNodeLinks, root.FindById("licensing"))
		generalNodeLinks = AppendIfNotNil(generalNodeLinks, root.FindById("org-settings"))
		generalNodeLinks = AppendIfNotNil(generalNodeLinks, root.FindById("server-settings"))
		generalNodeLinks = AppendIfNotNil(generalNodeLinks, root.FindById("global-orgs"))
		generalNodeLinks = AppendIfNotNil(generalNodeLinks, root.FindById("feature-toggles"))
		generalNodeLinks = AppendIfNotNil(generalNodeLinks, root.FindById("storage"))
		generalNodeLinks = AppendIfNotNil(generalNodeLinks, root.FindById("migrate-to-cloud"))

		generalNode := &NavLink{
			Text:     "General",
			SubTitle: "Manage default preferences and settings across Grafana",
			Id:       NavIDCfgGeneral,
			Url:      "/admin/general",
			Icon:     "shield",
			Children: generalNodeLinks,
		}

		pluginsNodeLinks := []*NavLink{}
		pluginsNodeLinks = AppendIfNotNil(pluginsNodeLinks, root.FindById("plugins"))
		pluginsNodeLinks = AppendIfNotNil(pluginsNodeLinks, root.FindById("datasources"))
		pluginsNodeLinks = AppendIfNotNil(pluginsNodeLinks, root.FindById("recordedQueries"))
		pluginsNodeLinks = AppendIfNotNil(pluginsNodeLinks, root.FindById("correlations"))
		pluginsNodeLinks = AppendIfNotNil(pluginsNodeLinks, root.FindById("plugin-page-grafana-cloud-link-app"))

		pluginsNode := &NavLink{
			Text:     "Plugins and data",
			SubTitle: "Install plugins and define the relationships between data",
			Id:       NavIDCfgPlugins,
			Url:      "/admin/plugins",
			Icon:     "shield",
			Children: pluginsNodeLinks,
		}

		accessNodeLinks := []*NavLink{}
		accessNodeLinks = AppendIfNotNil(accessNodeLinks, root.FindById("global-users"))
		accessNodeLinks = AppendIfNotNil(accessNodeLinks, root.FindById("teams"))
		accessNodeLinks = AppendIfNotNil(accessNodeLinks, root.FindById("standalone-plugin-page-/a/grafana-auth-app"))
		accessNodeLinks = AppendIfNotNil(accessNodeLinks, root.FindById("serviceaccounts"))
		accessNodeLinks = AppendIfNotNil(accessNodeLinks, root.FindById("apikeys"))

		usersNode := &NavLink{
			Text:     "Users and access",
			SubTitle: "Configure access for individual users, teams, and service accounts",
			Id:       NavIDCfgAccess,
			Url:      "/admin/access",
			Icon:     "shield",
			Children: accessNodeLinks,
		}

		if len(generalNode.Children) > 0 {
			adminNodeLinks = append(adminNodeLinks, generalNode)
		}

		if len(pluginsNode.Children) > 0 {
			adminNodeLinks = append(adminNodeLinks, pluginsNode)
		}

		if len(usersNode.Children) > 0 {
			adminNodeLinks = append(adminNodeLinks, usersNode)
		}

		authenticationNode := root.FindById("authentication")
		if authenticationNode != nil {
			authenticationNode.IsSection = true
			adminNodeLinks = append(adminNodeLinks, authenticationNode)
		}

		costManagementNode := root.FindById("plugin-page-grafana-costmanagementui-app")

		if costManagementNode != nil {
			adminNodeLinks = append(adminNodeLinks, costManagementNode)
		}

		costManagementMetricsNode := root.FindByURL("/a/grafana-costmanagementui-app/metrics")
		adaptiveMetricsNode := root.FindById("plugin-page-grafana-adaptive-metrics-app")

		if costManagementMetricsNode != nil && adaptiveMetricsNode != nil {
			costManagementMetricsNode.Children = append(costManagementMetricsNode.Children, adaptiveMetricsNode)
		}

		attributionsNode := root.FindById("plugin-page-grafana-attributions-app")

		if costManagementMetricsNode != nil && attributionsNode != nil {
			costManagementMetricsNode.Children = append(costManagementMetricsNode.Children, attributionsNode)
		}

		costManagementLogsNode := root.FindByURL("/a/grafana-costmanagementui-app/logs")
		logVolumeExplorerNode := root.FindById("plugin-page-grafana-logvolumeexplorer-app")

		if costManagementLogsNode != nil && logVolumeExplorerNode != nil {
			costManagementLogsNode.Children = append(costManagementLogsNode.Children, logVolumeExplorerNode)
		}

		if len(adminNodeLinks) > 0 {
			orgAdminNode.Children = adminNodeLinks
		} else {
			root.RemoveSection(orgAdminNode)
		}
	}
}

func AppendIfNotNil(children []*NavLink, newChild *NavLink) []*NavLink {
	if newChild != nil {
		return append(children, newChild)
	}

	return children
}

func FindById(nodes []*NavLink, id string) *NavLink {
	for _, child := range nodes {
		if child.Id == id {
			return child
		} else if len(child.Children) > 0 {
			if found := FindById(child.Children, id); found != nil {
				return found
			}
		}
	}

	return nil
}

func FindByURL(nodes []*NavLink, url string) *NavLink {
	for _, child := range nodes {
		if child.Url == url {
			return child
		} else if len(child.Children) > 0 {
			if found := FindByURL(child.Children, url); found != nil {
				return found
			}
		}
	}

	return nil
}