package ynison

import (
	"context"
	"encoding/json"
	"fmt"
	"sync"
	"time"

	"gitea.mrixs.me/Mrixs/yandex-music-api-go/internal/client"
	"gitea.mrixs.me/Mrixs/yandex-music-api-go/internal/ynison/proto"
	"github.com/gorilla/websocket"
)

// YnisonClient represents a Ynison WebSocket client
type YnisonClient struct {
	client      *client.Client
	conn        *websocket.Conn
	deviceID    string
	sessionID   int64
	mu          sync.Mutex
	handlers    map[string]func(*proto.PutYnisonStateResponse)
	ridCounter  int64
	connected   bool
	reconnectCh chan struct{}
	doneCh      chan struct{}
	wsURL       string    // For testing: override WebSocket URL
	closeOnce   sync.Once // Ensures doneCh is closed only once
}

// DeviceConfig holds device configuration for Ynison
type DeviceConfig struct {
	DeviceID    string
	Title       string
	DeviceType  proto.DeviceType
	AppName     string
	AppVersion  string
	CanBePlayer bool
	CanBeRemote bool
	VolumeGran  int
}

// NewYnisonClient creates a new Ynison client
func NewYnisonClient(c *client.Client, config DeviceConfig) *YnisonClient {
	if config.DeviceID == "" {
		config.DeviceID = fmt.Sprintf("go-ynison-%d", time.Now().UnixNano())
	}
	if config.Title == "" {
		config.Title = "Go Ynison Client"
	}
	if config.AppName == "" {
		config.AppName = "YandexMusicGo"
	}
	if config.AppVersion == "" {
		config.AppVersion = "1.0.0"
	}
	if config.VolumeGran == 0 {
		config.VolumeGran = 100
	}

	return &YnisonClient{
		client:      c,
		deviceID:    config.DeviceID,
		handlers:    make(map[string]func(*proto.PutYnisonStateResponse)),
		reconnectCh: make(chan struct{}, 1),
		doneCh:      make(chan struct{}),
	}
}

// Connect establishes a WebSocket connection to Ynison
func (y *YnisonClient) Connect(ctx context.Context) error {
	token := y.client.GetToken()
	if token == "" {
		return fmt.Errorf("no auth token available")
	}

	wsURL := y.wsURL
	if wsURL == "" {
		wsURL = fmt.Sprintf("wss://ynison.music.yandex.ru/redirector.YnisonRedirector/Connect?device_id=%s&token=%s", y.deviceID, token)
	}

	dialer := websocket.DefaultDialer
	conn, _, err := dialer.DialContext(ctx, wsURL, nil)
	if err != nil {
		return fmt.Errorf("failed to connect to Ynison: %w", err)
	}

	y.conn = conn
	y.connected = true

	// Start reading messages
	go y.readLoop(ctx)

	// Send initial UpdateFullState
	return y.sendUpdateFullState(ctx)
}

// overrideWSURL sets a custom WebSocket URL for testing
func (y *YnisonClient) overrideWSURL(url string) {
	y.wsURL = url
}

// Disconnect closes the WebSocket connection
func (y *YnisonClient) Disconnect() error {
	y.mu.Lock()
	defer y.mu.Unlock()

	if y.conn != nil {
		y.connected = false
		y.closeOnce.Do(func() {
			close(y.doneCh)
		})
		err := y.conn.Close()
		y.conn = nil // Prevent double close
		return err
	}
	return nil
}

// IsConnected returns true if the client is connected
func (y *YnisonClient) IsConnected() bool {
	y.mu.Lock()
	defer y.mu.Unlock()
	return y.connected
}

// readLoop reads messages from the WebSocket connection
func (y *YnisonClient) readLoop(ctx context.Context) {
	defer func() {
		y.mu.Lock()
		y.connected = false
		y.mu.Unlock()
		y.closeOnce.Do(func() {
			close(y.doneCh)
		})
	}()

	for {
		select {
		case <-ctx.Done():
			return
		case <-y.doneCh:
			return
		default:
			_, message, err := y.conn.ReadMessage()
			if err != nil {
				if websocket.IsUnexpectedCloseError(err, websocket.CloseGoingAway, websocket.CloseAbnormalClosure) {
					fmt.Printf("Ynison read error: %v\n", err)
				}
				return
			}

			var resp proto.PutYnisonStateResponse
			if err := json.Unmarshal(message, &resp); err != nil {
				fmt.Printf("Ynison unmarshal error: %v\n", err)
				continue
			}

			// Call registered handlers
			y.mu.Lock()
			for _, handler := range y.handlers {
				go handler(&resp)
			}
			y.mu.Unlock()
		}
	}
}

// sendUpdateFullState sends the initial full state update
func (y *YnisonClient) sendUpdateFullState(ctx context.Context) error {
	req := &proto.PutYnisonStateRequest{
		UpdateFullState: &proto.UpdateFullState{
			PlayerState: &proto.PlayerState{
				Status: &proto.PlayingStatus{
					ProgressMs:    0,
					DurationMs:    0,
					Paused:        true,
					PlaybackSpeed: 1.0,
					Version: &proto.UpdateVersion{
						DeviceId:    y.deviceID,
						Version:     1,
						TimestampMs: time.Now().UnixMilli(),
					},
				},
				PlayerQueue: &proto.PlayerQueue{
					EntityId:             "",
					EntityType:           proto.PlayerQueueEntityType_ENTITY_TYPE_UNSPECIFIED,
					CurrentPlayableIndex: -1,
					Options: &proto.PlayerStateOptions{
						RepeatMode: proto.PlayerStateOptionsRepeatMode_REPEAT_MODE_NONE,
					},
					Version: &proto.UpdateVersion{
						DeviceId:    y.deviceID,
						Version:     1,
						TimestampMs: time.Now().UnixMilli(),
					},
					EntityContext: proto.PlayerQueueEntityContext_ENTITY_CONTEXT_UNSPECIFIED,
				},
				PlayerQueueInjectOptional: &proto.PlayerQueueInject{
					PlayingStatus: &proto.PlayingStatus{
						ProgressMs:    0,
						DurationMs:    0,
						Paused:        true,
						PlaybackSpeed: 1.0,
						Version: &proto.UpdateVersion{
							DeviceId:    y.deviceID,
							Version:     1,
							TimestampMs: time.Now().UnixMilli(),
						},
					},
					Playable: &proto.PlayerQueueInjectPlayable{
						PlayableId:   "",
						PlayableType: proto.PlayerQueueInjectPlayablePlayableType_INJECT_PLAYABLE_TYPE_UNSPECIFIED,
						Title:        "",
					},
					Version: &proto.UpdateVersion{
						DeviceId:    y.deviceID,
						Version:     1,
						TimestampMs: time.Now().UnixMilli(),
					},
				},
			},
			IsCurrentlyActive: false,
			Device: &proto.UpdateDevice{
				Info: &proto.DeviceInfo{
					DeviceId:   y.deviceID,
					Title:      "Go Ynison Client",
					Type:       proto.DeviceType_DEVICE_TYPE_WEB_DESKTOP,
					AppName:    "YandexMusicGo",
					AppVersion: "1.0.0",
				},
				Volume: 0.5,
				Capabilities: &proto.DeviceCapabilities{
					CanBePlayer:           true,
					CanBeRemoteController: true,
					VolumeGranularity:     100,
				},
				VolumeInfo: &proto.DeviceVolume{
					Volume: 0.5,
					Version: &proto.UpdateVersion{
						DeviceId:    y.deviceID,
						Version:     1,
						TimestampMs: time.Now().UnixMilli(),
					},
				},
			},
		},
		PlayerActionTimestampMs:  time.Now().UnixMilli(),
		Rid:                      y.nextRid(),
		ActivityInterceptionType: proto.PutYnisonStateRequestActivityInterceptionType_INTERCEPTION_DO_NOT_INTERCEPT_BY_DEFAULT,
	}

	return y.sendRequest(ctx, req)
}

// nextRid generates the next request ID
func (y *YnisonClient) nextRid() string {
	y.ridCounter++
	return fmt.Sprintf("%s-%d", y.deviceID, y.ridCounter)
}

// sendRequest sends a request to the Ynison server
func (y *YnisonClient) sendRequest(ctx context.Context, req *proto.PutYnisonStateRequest) error {
	y.mu.Lock()
	defer y.mu.Unlock()

	if !y.connected || y.conn == nil {
		return fmt.Errorf("not connected")
	}

	data, err := json.Marshal(req)
	if err != nil {
		return fmt.Errorf("failed to marshal request: %w", err)
	}

	return y.conn.WriteMessage(websocket.TextMessage, data)
}

// RegisterHandler registers a response handler
func (y *YnisonClient) RegisterHandler(name string, handler func(*proto.PutYnisonStateResponse)) {
	y.mu.Lock()
	defer y.mu.Unlock()
	y.handlers[name] = handler
}

// UnregisterHandler removes a response handler
func (y *YnisonClient) UnregisterHandler(name string) {
	y.mu.Lock()
	defer y.mu.Unlock()
	delete(y.handlers, name)
}

// UpdatePlayingStatus updates the playing status
func (y *YnisonClient) UpdatePlayingStatus(ctx context.Context, status *proto.PlayingStatus) error {
	req := &proto.PutYnisonStateRequest{
		UpdatePlayingStatus: &proto.UpdatePlayingStatus{
			PlayingStatus: status,
		},
		PlayerActionTimestampMs: time.Now().UnixMilli(),
		Rid:                     y.nextRid(),
	}
	return y.sendRequest(ctx, req)
}

// UpdateVolume updates the volume
func (y *YnisonClient) UpdateVolume(ctx context.Context, deviceID string, volume float64, version *proto.UpdateVersion) error {
	req := &proto.PutYnisonStateRequest{
		UpdateVolumeInfo: &proto.UpdateVolumeInfo{
			DeviceId: deviceID,
			VolumeInfo: &proto.DeviceVolume{
				Volume:  volume,
				Version: version,
			},
		},
		PlayerActionTimestampMs: time.Now().UnixMilli(),
		Rid:                     y.nextRid(),
	}
	return y.sendRequest(ctx, req)
}

// UpdateActiveDevice updates the active device
func (y *YnisonClient) UpdateActiveDevice(ctx context.Context, deviceID string) error {
	req := &proto.PutYnisonStateRequest{
		UpdateActiveDevice: &proto.UpdateActiveDevice{
			DeviceIdOptional: deviceID,
		},
		PlayerActionTimestampMs: time.Now().UnixMilli(),
		Rid:                     y.nextRid(),
	}
	return y.sendRequest(ctx, req)
}

// UpdatePlayerState updates the player state (queue, repeat, shuffle)
func (y *YnisonClient) UpdatePlayerState(ctx context.Context, state *proto.PlayerState) error {
	req := &proto.PutYnisonStateRequest{
		UpdatePlayerState: &proto.UpdatePlayerState{
			PlayerState: state,
		},
		PlayerActionTimestampMs: time.Now().UnixMilli(),
		Rid:                     y.nextRid(),
	}
	return y.sendRequest(ctx, req)
}

// UpdatePlayerQueueInject updates the injected queue entity
func (y *YnisonClient) UpdatePlayerQueueInject(ctx context.Context, inject *proto.PlayerQueueInject) error {
	req := &proto.PutYnisonStateRequest{
		UpdatePlayerQueueInject: &proto.UpdatePlayerQueueInject{
			PlayerQueueInject: inject,
		},
		PlayerActionTimestampMs: time.Now().UnixMilli(),
		Rid:                     y.nextRid(),
	}
	return y.sendRequest(ctx, req)
}

// SyncStateFromEOV requests synchronization from EOV
func (y *YnisonClient) SyncStateFromEOV(ctx context.Context, actualQueueID string) error {
	req := &proto.PutYnisonStateRequest{
		SyncStateFromEov: &proto.SyncStateFromEOV{
			ActualQueueId: actualQueueID,
		},
		PlayerActionTimestampMs: time.Now().UnixMilli(),
		Rid:                     y.nextRid(),
	}
	return y.sendRequest(ctx, req)
}

// GetDevices returns the list of connected devices from the last response
func (y *YnisonClient) GetDevices() []*proto.Device {
	// This would need to be implemented with proper state tracking
	return nil
}

// GetActiveDeviceID returns the active device ID from the last response
func (y *YnisonClient) GetActiveDeviceID() string {
	// This would need to be implemented with proper state tracking
	return ""
}

// GetPlayerState returns the current player state from the last response
func (y *YnisonClient) GetPlayerState() *proto.PlayerState {
	// This would need to be implemented with proper state tracking
	return nil
}

// WaitForConnection waits for the connection to be established or context to be done
func (y *YnisonClient) WaitForConnection(ctx context.Context) error {
	select {
	case <-ctx.Done():
		return ctx.Err()
	case <-y.doneCh:
		return fmt.Errorf("connection closed")
	default:
		if y.IsConnected() {
			return nil
		}
		return fmt.Errorf("not connected")
	}
}