package app

import (
	"cwtch.im/cwtch/app/plugins"
	"cwtch.im/cwtch/event"
	"cwtch.im/cwtch/model"
	"cwtch.im/cwtch/model/attr"
	"cwtch.im/cwtch/model/constants"
	"cwtch.im/cwtch/peer"
	"cwtch.im/cwtch/protocol/connections"
	"cwtch.im/cwtch/storage"
	"git.openprivacy.ca/openprivacy/connectivity"
	"git.openprivacy.ca/openprivacy/log"
	"os"
	path "path/filepath"
	"strconv"
	"sync"
)

type application struct {
	eventBuses map[string]event.Manager
	directory  string
	coremutex  sync.Mutex
	appletPeers
	appletACN
	appletPlugins
	engines  map[string]connections.Engine
	appBus   event.Manager
	appmutex sync.Mutex
}

// Application is a full cwtch peer application. It allows management, usage and storage of multiple peers
type Application interface {
	LoadProfiles(password string)
	CreateTaggedPeer(name string, password string, tag string)
	ImportProfile(exportedCwtchFile string, password string) (peer.CwtchPeer, error)
	DeletePeer(onion string, currentPassword string)
	AddPeerPlugin(onion string, pluginID plugins.PluginID)
	LaunchPeers()

	GetPrimaryBus() event.Manager
	GetEventBus(onion string) event.Manager
	QueryACNStatus()
	QueryACNVersion()

	ShutdownPeer(string)
	Shutdown()

	GetPeer(onion string) peer.CwtchPeer
	ListProfiles() []string
}

// LoadProfileFn is the function signature for a function in an app that loads a profile
type LoadProfileFn func(profile peer.CwtchPeer)

// NewApp creates a new app with some environment awareness and initializes a Tor Manager
func NewApp(acn connectivity.ACN, appDirectory string) Application {
	log.Debugf("NewApp(%v)\n", appDirectory)
	os.MkdirAll(path.Join(appDirectory, "profiles"), 0700)

	app := &application{engines: make(map[string]connections.Engine), eventBuses: make(map[string]event.Manager), directory: appDirectory, appBus: event.NewEventManager()}
	app.appletPeers.init()

	app.appletACN.init(acn, app.getACNStatusHandler(), app.getACNVersionHandler())
	return app
}

func (app *application) CreateTaggedPeer(name string, password string, tag string) {
	app.appmutex.Lock()
	defer app.appmutex.Unlock()

	profileDirectory := path.Join(app.directory, "profiles", model.GenerateRandomID())

	profile, err := peer.CreateEncryptedStorePeer(profileDirectory, name, password)
	if err != nil {
		log.Errorf("Error Creating Peer: %v", err)
		app.appBus.Publish(event.NewEventList(event.PeerError, event.Error, err.Error()))
		return
	}

	eventBus := event.NewEventManager()
	app.eventBuses[profile.GetOnion()] = eventBus
	profile.Init(app.eventBuses[profile.GetOnion()])
	app.peers[profile.GetOnion()] = profile
	app.engines[profile.GetOnion()], _ = profile.GenerateProtocolEngine(app.acn, app.eventBuses[profile.GetOnion()])

	if tag != "" {
		profile.SetScopedZonedAttribute(attr.LocalScope, attr.ProfileZone, constants.Tag, tag)
	}

	app.appBus.Publish(event.NewEvent(event.NewPeer, map[event.Field]string{event.Identity: profile.GetOnion(), event.Created: event.True}))
}

func (app *application) DeletePeer(onion string, password string) {
	log.Infof("DeletePeer called on %v\n", onion)
	app.appmutex.Lock()
	defer app.appmutex.Unlock()

	if app.peers[onion].CheckPassword(password) {
		app.appletPlugins.ShutdownPeer(onion)
		app.plugins.Delete(onion)

		// Shutdown and Remove the Engine
		app.engines[onion].Shutdown()
		delete(app.engines, onion)

		app.peers[onion].Shutdown()
		app.peers[onion].Delete()
		delete(app.peers, onion)
		app.eventBuses[onion].Publish(event.NewEventList(event.ShutdownPeer, event.Identity, onion))

		app.coremutex.Lock()
		defer app.coremutex.Unlock()
		app.eventBuses[onion].Shutdown()
		delete(app.eventBuses, onion)

		log.Debugf("Delete peer for %v Done\n", onion)
		app.appBus.Publish(event.NewEventList(event.PeerDeleted, event.Identity, onion))
		return
	}
	app.appBus.Publish(event.NewEventList(event.AppError, event.Error, event.PasswordMatchError, event.Identity, onion))
}

func (app *application) AddPeerPlugin(onion string, pluginID plugins.PluginID) {
	app.AddPlugin(onion, pluginID, app.eventBuses[onion], app.acn)
}

func (app *application) ImportProfile(exportedCwtchFile string, password string) (peer.CwtchPeer, error) {
	profileDirectory := path.Join(app.directory, "profiles")
	profile, err := peer.ImportProfile(exportedCwtchFile, profileDirectory, password)
	if profile != nil || err == nil {
		app.installProfile(profile)
	}
	return profile, err
}

// LoadProfiles takes a password and attempts to load any profiles it can from storage with it and create Peers for them
func (app *application) LoadProfiles(password string) {
	count := 0
	migrating := false

	files, err := os.ReadDir(path.Join(app.directory, "profiles"))
	if err != nil {
		log.Errorf("error: cannot read profiles directory: %v", err)
		return
	}

	for _, file := range files {
		// Attempt to load an encrypted database
		profileDirectory := path.Join(app.directory, "profiles", file.Name())
		profile, err := peer.FromEncryptedDatabase(profileDirectory, password)
		loaded := false
		if err == nil {
			// return the load the profile...
			log.Infof("loading profile from new-type storage database...")
			loaded = app.installProfile(profile)
		} else { // On failure attempt to load a legacy profile
			profileStore, err := storage.LoadProfileWriterStore(profileDirectory, password)
			if err != nil {
				continue
			}
			log.Infof("found legacy profile. importing to new database structure...")
			legacyProfile := profileStore.GetProfileCopy(true)
			if !migrating {
				migrating = true
				app.appBus.Publish(event.NewEventList(event.StartingStorageMiragtion))
			}

			cps, err := peer.CreateEncryptedStore(profileDirectory, password)
			if err != nil {
				log.Errorf("error creating encrypted store: %v", err)
			}
			profile := peer.ImportLegacyProfile(legacyProfile, cps)
			loaded = app.installProfile(profile)
		}
		if loaded {
			count++
		}
	}
	if count == 0 {
		message := event.NewEventList(event.AppError, event.Error, event.AppErrLoaded0)
		app.appBus.Publish(message)
	}
	if migrating {
		app.appBus.Publish(event.NewEventList(event.DoneStorageMigration))
	}
}

// installProfile takes a profile and if it isn't loaded in the app, installs it and returns true
func (app *application) installProfile(profile peer.CwtchPeer) bool {
	app.appmutex.Lock()
	defer app.appmutex.Unlock()

	// Only attempt to finalize the profile if we don't have one loaded...
	if app.peers[profile.GetOnion()] == nil {
		eventBus := event.NewEventManager()
		app.eventBuses[profile.GetOnion()] = eventBus
		profile.Init(app.eventBuses[profile.GetOnion()])
		app.peers[profile.GetOnion()] = profile
		app.engines[profile.GetOnion()], _ = profile.GenerateProtocolEngine(app.acn, app.eventBuses[profile.GetOnion()])
		app.appBus.Publish(event.NewEvent(event.NewPeer, map[event.Field]string{event.Identity: profile.GetOnion(), event.Created: event.False}))
		return true
	}
	// Otherwise shutdown the connections
	profile.Shutdown()
	return false
}

// GetPrimaryBus returns the bus the Application uses for events that aren't peer specific
func (app *application) GetPrimaryBus() event.Manager {
	return app.appBus
}

// GetEventBus returns a cwtchPeer's event bus
func (app *application) GetEventBus(onion string) event.Manager {
	if manager, ok := app.eventBuses[onion]; ok {
		return manager
	}
	return nil
}

func (app *application) getACNStatusHandler() func(int, string) {
	return func(progress int, status string) {
		progStr := strconv.Itoa(progress)
		app.appmutex.Lock()
		app.appBus.Publish(event.NewEventList(event.ACNStatus, event.Progress, progStr, event.Status, status))
		for _, bus := range app.eventBuses {
			bus.Publish(event.NewEventList(event.ACNStatus, event.Progress, progStr, event.Status, status))
		}
		app.appmutex.Unlock()
	}
}

func (app *application) getACNVersionHandler() func(string) {
	return func(version string) {
		app.appmutex.Lock()
		defer app.appmutex.Unlock()
		app.appBus.Publish(event.NewEventList(event.ACNVersion, event.Data, version))
	}
}

func (app *application) QueryACNStatus() {
	prog, status := app.acn.GetBootstrapStatus()
	app.getACNStatusHandler()(prog, status)
}

func (app *application) QueryACNVersion() {
	version := app.acn.GetVersion()
	app.appBus.Publish(event.NewEventList(event.ACNVersion, event.Data, version))
}

// ShutdownPeer shuts down a peer and removes it from the app's management
func (app *application) ShutdownPeer(onion string) {
	app.appmutex.Lock()
	defer app.appmutex.Unlock()
	app.eventBuses[onion].Shutdown()
	delete(app.eventBuses, onion)
	app.peers[onion].Shutdown()
	delete(app.peers, onion)
	app.engines[onion].Shutdown()
	delete(app.engines, onion)
	app.appletPlugins.Shutdown()
}

// Shutdown shutsdown all peers of an app and then the tormanager
func (app *application) Shutdown() {
	for id, peer := range app.peers {
		log.Debugf("Shutting Down Peer %v", id)
		peer.Shutdown()
		log.Debugf("Shutting Down Plugins for %v", id)
		app.appletPlugins.ShutdownPeer(id)
		log.Debugf("Shutting Down Engines for  %v", id)
		app.engines[id].Shutdown()
		log.Debugf("Shutting Down Bus for  %v", id)
		app.eventBuses[id].Shutdown()
		log.Debugf("Done Shutdown for peer %v", id)
	}
	log.Debugf("Shutting Down App")
	app.appBus.Shutdown()
	log.Debugf("Shut Down Complete")
}