// Discord Rich Presence Plugin for Navidrome
//
// This plugin integrates Navidrome with Discord Rich Presence. It shows how a plugin can
// keep a real-time connection to an external service while remaining completely stateless.
//
// Capabilities: Scrobbler, SchedulerCallback, WebSocketCallback
//
// NOTE: This plugin is for demonstration purposes only. It relies on the user's Discord
// token being stored in the Navidrome configuration file, which is not secure and may be
// against Discord's terms of service. Use it at your own risk.
package main

import (
	"encoding/json"
	"fmt"
	"strings"
	"time"

	"github.com/navidrome/navidrome/plugins/pdk/go/host"
	"github.com/navidrome/navidrome/plugins/pdk/go/pdk"
	"github.com/navidrome/navidrome/plugins/pdk/go/scheduler"
	"github.com/navidrome/navidrome/plugins/pdk/go/scrobbler"
	"github.com/navidrome/navidrome/plugins/pdk/go/websocket"
)

// Configuration keys
const (
	clientIDKey     = "clientid"
	usersKey        = "users"
	activityNameKey = "activityname"
	spotifyLinksKey = "spotifylinks"
)

const (
	navidromeWebsiteURL = "https://www.navidrome.org"

	// navidromeLogoURL is the small overlay image shown in the bottom-right of the album art.
	// The file is stored in the plugins' GitHub repository so Discord can fetch it as an external asset.
	navidromeLogoURL = "https://raw.githubusercontent.com/navidrome/website/refs/heads/master/assets/icons/logo.webp"
)

// Activity name display options
const (
	activityNameDefault = "Default"
	activityNameTrack   = "Track"
	activityNameArtist  = "Artist"
	activityNameAlbum   = "Album"
)

// userToken represents a user-token mapping from the config
type userToken struct {
	Username string `json:"username"`
	Token    string `json:"token"`
}

// discordPlugin implements the scrobbler and scheduler interfaces.
type discordPlugin struct{}

// rpc handles Discord gateway communication (via websockets).
var rpc = &discordRPC{}

// init registers the plugin capabilities
func init() {
	scrobbler.Register(&discordPlugin{})
	scheduler.Register(&discordPlugin{})
	websocket.Register(rpc)
}

// getConfig loads the plugin configuration.
func getConfig() (clientID string, users map[string]string, err error) {
	clientID, ok := pdk.GetConfig(clientIDKey)
	if !ok || clientID == "" {
		pdk.Log(pdk.LogWarn, "missing ClientID in configuration")
		return "", nil, nil
	}

	// Get the users array from config
	usersJSON, ok := pdk.GetConfig(usersKey)
	if !ok || usersJSON == "" {
		pdk.Log(pdk.LogWarn, "no users configured")
		return clientID, nil, nil
	}

	// Parse the JSON array
	var userTokens []userToken
	if err := json.Unmarshal([]byte(usersJSON), &userTokens); err != nil {
		pdk.Log(pdk.LogError, fmt.Sprintf("failed to parse users config: %v", err))
		return clientID, nil, nil
	}

	if len(userTokens) == 0 {
		pdk.Log(pdk.LogWarn, "no users configured")
		return clientID, nil, nil
	}

	// Build the users map
	users = make(map[string]string)
	for _, ut := range userTokens {
		if ut.Username != "" && ut.Token != "" {
			users[ut.Username] = ut.Token
		}
	}

	if len(users) == 0 {
		pdk.Log(pdk.LogWarn, "no valid users configured")
		return clientID, nil, nil
	}

	return clientID, users, nil
}

// ============================================================================
// Scrobbler Implementation
// ============================================================================

// IsAuthorized checks if a user is authorized for Discord Rich Presence.
func (p *discordPlugin) IsAuthorized(input scrobbler.IsAuthorizedRequest) (bool, error) {
	_, users, err := getConfig()
	if err != nil {
		return false, fmt.Errorf("failed to check user authorization: %w", err)
	}

	_, authorized := users[input.Username]
	pdk.Log(pdk.LogInfo, fmt.Sprintf("IsAuthorized for user %s: %v", input.Username, authorized))
	return authorized, nil
}

// NowPlaying sends a now playing notification to Discord.
func (p *discordPlugin) NowPlaying(input scrobbler.NowPlayingRequest) error {
	pdk.Log(pdk.LogInfo, fmt.Sprintf("Setting presence for user %s, track: %s", input.Username, input.Track.Title))

	// Load configuration
	clientID, users, err := getConfig()
	if err != nil {
		return fmt.Errorf("%w: failed to get config: %v", scrobbler.ScrobblerErrorRetryLater, err)
	}

	// Check authorization
	userToken, authorized := users[input.Username]
	if !authorized {
		return fmt.Errorf("%w: user '%s' not authorized", scrobbler.ScrobblerErrorNotAuthorized, input.Username)
	}

	// Connect to Discord
	if err := rpc.connect(input.Username, userToken); err != nil {
		return fmt.Errorf("%w: failed to connect to Discord: %v", scrobbler.ScrobblerErrorRetryLater, err)
	}

	// Cancel any existing completion schedule
	_ = host.SchedulerCancelSchedule(fmt.Sprintf("%s-clear", input.Username))

	// Calculate timestamps
	now := time.Now().Unix()
	startTime := (now - int64(input.Position)) * 1000
	endTime := startTime + int64(input.Track.Duration)*1000

	// Resolve the activity name based on configuration
	activityName := "Navidrome"
	statusDisplayType := statusDisplayDetails
	activityNameOption, _ := pdk.GetConfig(activityNameKey)
	switch activityNameOption {
	case activityNameTrack:
		activityName = input.Track.Title
		statusDisplayType = statusDisplayName
	case activityNameAlbum:
		activityName = input.Track.Album
		statusDisplayType = statusDisplayName
	case activityNameArtist:
		activityName = input.Track.Artist
		statusDisplayType = statusDisplayName
	}

	// Resolve Spotify URLs if enabled
	var spotifyURL, artistSearchURL string
	spotifyLinksOption, _ := pdk.GetConfig(spotifyLinksKey)
	if spotifyLinksOption == "true" {
		spotifyURL = resolveSpotifyURL(input.Track)
		artistSearchURL = spotifySearchURL(input.Track.Artist)
	}

	// Send activity update
	if err := rpc.sendActivity(clientID, input.Username, userToken, activity{
		Application:       clientID,
		Name:              activityName,
		Type:              2, // Listening
		Details:           input.Track.Title,
		DetailsURL:        spotifyURL,
		State:             input.Track.Artist,
		StateURL:          artistSearchURL,
		StatusDisplayType: statusDisplayType,
		Timestamps: activityTimestamps{
			Start: startTime,
			End:   endTime,
		},
		Assets: activityAssets{
			LargeImage: getImageURL(input.Username, input.Track.ID),
			LargeText:  input.Track.Album,
			LargeURL:   spotifyURL,
			SmallImage: navidromeLogoURL,
			SmallText:  "Navidrome",
			SmallURL:   navidromeWebsiteURL,
		},
	}); err != nil {
		return fmt.Errorf("%w: failed to send activity: %v", scrobbler.ScrobblerErrorRetryLater, err)
	}

	// Schedule a timer to clear the activity after the track completes
	remainingSeconds := int32(input.Track.Duration) - input.Position + 5
	_, err = host.SchedulerScheduleOneTime(remainingSeconds, payloadClearActivity, fmt.Sprintf("%s-clear", input.Username))
	if err != nil {
		pdk.Log(pdk.LogWarn, fmt.Sprintf("Failed to schedule completion timer: %v", err))
	}

	return nil
}

// Scrobble handles scrobble requests (no-op for Discord).
func (p *discordPlugin) Scrobble(_ scrobbler.ScrobbleRequest) error {
	// Discord Rich Presence doesn't need scrobble events
	return nil
}

// ============================================================================
// Scheduler Callback Implementation
// ============================================================================

// OnCallback handles scheduler callbacks.
func (p *discordPlugin) OnCallback(input scheduler.SchedulerCallbackRequest) error {
	pdk.Log(pdk.LogDebug, fmt.Sprintf("Scheduler callback: id=%s, payload=%s, recurring=%v", input.ScheduleID, input.Payload, input.IsRecurring))

	// Route based on payload
	switch input.Payload {
	case payloadHeartbeat:
		// Heartbeat callback - scheduleId is the username
		if err := rpc.handleHeartbeatCallback(input.ScheduleID); err != nil {
			return err
		}

	case payloadClearActivity:
		// Clear activity callback - scheduleId is "username-clear"
		username := strings.TrimSuffix(input.ScheduleID, "-clear")
		if err := rpc.handleClearActivityCallback(username); err != nil {
			return err
		}

	default:
		pdk.Log(pdk.LogWarn, fmt.Sprintf("Unknown scheduler callback payload: %s", input.Payload))
	}

	return nil
}

func main() {}