import * as AWS from 'aws-sdk'
import * as path from 'path'
import {FileHandler} from "../types/FileHandler";
import {GQLFileInput} from "../types/GQLFileInput";

const uuidv1 = require('uuid/v1')

export interface AwsFileHandlerConfig {
    awsKey: string
    awsSecret: string
    bucket: string
    folder: string
    region:string
}

export class AwsS3FileHandler implements FileHandler {
    config: AwsFileHandlerConfig
    constructor(conf: AwsFileHandlerConfig) {
        this.config = conf
    }
    deleteFile(path: string): Promise<void> {
        const s3 = new AWS.S3({
            accessKeyId: this.config.awsKey,
            secretAccessKey: this.config.awsSecret,
            region:this.config.region
        })

        const fileKeyRegEx = new RegExp(`${this.config.folder}(.*)`)
        const result=fileKeyRegEx.exec(path)
        if (!result) throw new Error(`Unable to extract file key from path ${path} and folder ${this.config.folder}`)
        const fileKey = result[0]

        const params = {
            Bucket: this.config.bucket,
            Key: fileKey, // File name you want to save as in S3
        }

        return new Promise((resolve, reject) => {
            s3.deleteObject(
                params,
                (err: Error, s3Data: AWS.S3.Types.DeleteObjectOutput) => {
                    if (err) {
                        reject(err)
                        return
                    }
                    resolve()
                }
            )
        })

        return Promise.resolve()
    }

    saveFile(data: GQLFileInput): Promise<string> {
        const s3 = new AWS.S3({
            accessKeyId: this.config.awsKey,
            secretAccessKey: this.config.awsSecret,
            region:this.config.region
        })
        let buff = new Buffer(data.body.replace(/^data.*base64,/, ''), 'base64')
        let ext = path.extname(data.file_name)
        let fileName = `${this.config.folder}/${uuidv1()}${ext}`
        // Setting up S3 upload parameters
        const params = {
            Bucket: this.config.bucket,
            Key: fileName, // File name you want to save as in S3
            Body: buff,
            ACL: 'public-read',
        }
        return new Promise((resolve, reject) => {
            s3.upload(params, function(
                err: Error,
                s3Data: AWS.S3.ManagedUpload.SendData
            ) {
                if (err) {
                    reject(err)
                    return
                }
                resolve(s3Data.Location)
            })
        })
    }
}