// Copyright 2023 GoEdge CDN goedge.cdn@gmail.com. All rights reserved. Official site: https://goedge.cn .
//go:build plus

package oss

import (
	"bytes"
	"errors"
	"github.com/TeaOSLab/EdgeCommon/pkg/serverconfigs/ossconfigs"
	"github.com/aliyun/aliyun-oss-go-sdk/oss"
	"github.com/iwind/TeaGo/types"
	"io"
	"net/http"
)

type AliyunOSSProvider struct {
	bucket *oss.Bucket
}

func NewAliyunOSSProvider() *AliyunOSSProvider {
	return &AliyunOSSProvider{}
}

func (this *AliyunOSSProvider) Init(options ossconfigs.OSSOptions, bucketName string) error {
	realOptions, ok := options.(*ossconfigs.AliyunOSSProviderOptions)
	if !ok {
		return errors.New("invalid options for 'AliyunOSSProvider'")
	}

	client, err := oss.New(realOptions.Endpoint, realOptions.AccessKeyId, realOptions.AccessKeySecret)
	if err != nil {
		return err
	}

	bucket, err := client.Bucket(bucketName)
	if err != nil {
		return err
	}
	this.bucket = bucket

	return nil
}

func (this *AliyunOSSProvider) Head(key string) (httpResponse *http.Response, nativeErrCode string, err error) {
	header, respErr := this.bucket.GetObjectMeta(key)
	if err != nil {
		nativeErrCode, err = this.parseErr(respErr)
		return
	}

	// not found
	if len(header) == 0 {
		header = http.Header{"Content-Length": []string{"0"}}

		httpResponse = &http.Response{
			StatusCode:    http.StatusNotFound,
			Header:        header,
			Body:          io.NopCloser(bytes.NewReader(nil)),
			ContentLength: 0,
		}
		return
	}

	httpResponse = &http.Response{
		StatusCode:    http.StatusOK,
		Header:        header,
		Body:          io.NopCloser(bytes.NewReader(nil)),
		ContentLength: types.Int64(header.Get("Content-Length")),
	}
	return
}

func (this *AliyunOSSProvider) Get(key string) (httpResponse *http.Response, nativeErrCode string, err error) {
	body, respErr := this.bucket.GetObject(key)
	if respErr != nil {
		nativeErrCode, err = this.parseErr(respErr)
		return
	}

	resp, ok := body.(*oss.Response)
	if ok {
		httpResponse = &http.Response{
			StatusCode:    http.StatusOK,
			Header:        resp.Headers,
			Body:          resp.Body,
			ContentLength: types.Int64(resp.Headers.Get("Content-Length")),
		}
		return
	}

	httpResponse = &http.Response{
		StatusCode: http.StatusOK,
		Body:       body,
	}
	return
}

func (this *AliyunOSSProvider) GetRange(key string, bytesRange string) (httpResponse *http.Response, nativeErrCode string, err error) {
	rangeResult, parseOk := httpRequestParseRangeHeader(bytesRange)
	if !parseOk || len(rangeResult) == 0 {
		return this.Get(key)
	}

	var firstRange = rangeResult[0]
	var start = firstRange.Start()
	var end = firstRange.End()
	if start < 0 || end < 0 || start > end {
		return this.Get(key)
	}

	body, respErr := this.bucket.GetObject(key, oss.Range(start, end))
	if respErr != nil {
		nativeErrCode, err = this.parseErr(respErr)
		return
	}

	resp, ok := body.(*oss.Response)
	if ok {
		httpResponse = &http.Response{
			StatusCode:    resp.StatusCode,
			Header:        resp.Headers,
			Body:          resp.Body,
			ContentLength: types.Int64(resp.Headers.Get("Content-Length")),
		}
		return
	}

	httpResponse = &http.Response{
		StatusCode: http.StatusPartialContent,
		Body:       body,
	}
	return
}

func (this *AliyunOSSProvider) parseErr(err error) (errCode string, resultErr error) {
	if err == nil {
		return
	}

	resultErr = err

	serviceErr, ok := err.(oss.ServiceError)
	if ok {
		errCode = serviceErr.Code

		// 特殊错误
		if errCode == "NoSuchBucket" {
			resultErr = errNoBucket
			return
		}

		if errCode == "NoSuchKey" {
			resultErr = errNotFound
		}

		if errCode == "RequestTimeout" {
			resultErr = errRequestTimeout
			return
		}
	}

	return
}