import { BleProtocolService } from './BleProtocolService';
import { COMMAND_TYPES } from '../protocol/Constants';


export class FileTransferService {
    private static instance: FileTransferService;
    private protocol = BleProtocolService.getInstance();
    
    private constructor() {}

    public static getInstance(): FileTransferService {
        if (!FileTransferService.instance) {
            FileTransferService.instance = new FileTransferService();
        }
        return FileTransferService.instance;
    }

    public async transferFile(deviceId: string, filePath: string, type: COMMAND_TYPES, onProgress?: (progress: number) => void): Promise<void> {
        try {
            const response = await fetch(filePath);
            if (!response.ok) {
                throw new Error(`Failed to load file: ${response.statusText}`);
            }
            const blob = await response.blob();
            
            const reader = new FileReader();
            const arrayBuffer = await new Promise<ArrayBuffer>((resolve, reject) => {
                reader.onload = () => resolve(reader.result as ArrayBuffer);
                reader.onerror = reject;
                reader.readAsArrayBuffer(blob);
            });
            
            await this.protocol.send(deviceId, type, arrayBuffer, onProgress);
        } catch (e) {
            console.error("File transfer failed", e);
            throw e;
        }
    }
    
    public async transferOta(deviceId: string, filePath: string) {
        return this.transferFile(deviceId, filePath, COMMAND_TYPES.OTA_PACKAGE);
    }

    public async transferBootAnimation(deviceId: string, filePath: string) {
        return this.transferFile(deviceId, filePath, COMMAND_TYPES.TRANSFER_BOOT_ANIMATION);
    }

    public async transferWatchfaceStyle(deviceId: string, filePath: string) {
        return this.transferFile(deviceId, filePath, COMMAND_TYPES.TRANSFER_AVI_VIDEO);
    }
}