// Copyright 2021 Liuxiangchao iwind.liu@gmail.com. All rights reserved.
//go:build !windows

package nodes

import (
	"github.com/TeaOSLab/EdgeNode/internal/caches"
	"github.com/TeaOSLab/EdgeNode/internal/remotelogs"
	"github.com/TeaOSLab/EdgeNode/internal/utils/readers"
	"github.com/TeaOSLab/EdgeNode/internal/utils/writers"
	"github.com/iwind/TeaGo/types"
	"github.com/iwind/gowebp"
	"image"
	"image/gif"
	"strings"
	"sync/atomic"
)

// 结束WebP
func (this *HTTPWriter) finishWebP() {
	// 处理WebP
	if this.webpIsEncoding {
		atomic.AddInt32(&webPThreads, 1)
		defer func() {
			atomic.AddInt32(&webPThreads, -1)
		}()

		var webpCacheWriter caches.Writer

		// 准备WebP Cache
		if this.cacheReader != nil || this.cacheWriter != nil {
			var cacheKey = ""
			var expiredAt int64 = 0

			if this.cacheReader != nil {
				cacheKey = this.req.cacheKey + caches.SuffixWebP
				expiredAt = this.cacheReader.ExpiresAt()
			} else if this.cacheWriter != nil {
				cacheKey = this.cacheWriter.Key() + caches.SuffixWebP
				expiredAt = this.cacheWriter.ExpiredAt()
			}

			webpCacheWriter, _ = this.cacheStorage.OpenWriter(cacheKey, expiredAt, this.StatusCode(), -1, -1, -1, false)
			if webpCacheWriter != nil {
				// 写入Header
				for k, v := range this.Header() {
					if this.shouldIgnoreHeader(k) {
						continue
					}

					// 这里是原始的数据，不需要内容编码
					if k == "Content-Encoding" || k == "Transfer-Encoding" {
						continue
					}
					for _, v1 := range v {
						_, err := webpCacheWriter.WriteHeader([]byte(k + ":" + v1 + "\n"))
						if err != nil {
							remotelogs.Error("HTTP_WRITER", "write webp cache failed: "+err.Error())
							_ = webpCacheWriter.Discard()
							webpCacheWriter = nil
							break
						}
					}
				}

				if webpCacheWriter != nil {
					var teeWriter = writers.NewTeeWriterCloser(this.writer, webpCacheWriter)
					teeWriter.OnFail(func(err error) {
						if webpCacheWriter != nil {
							_ = webpCacheWriter.Discard()
						}
						webpCacheWriter = nil
					})
					this.writer = teeWriter
				}
			}
		}

		var reader = readers.NewBytesCounterReader(this.rawReader)

		var imageData image.Image
		var gifImage *gif.GIF
		var isGif = strings.Contains(this.webpOriginContentType, "image/gif")
		var err error
		if isGif {
			gifImage, err = gif.DecodeAll(reader)
			if gifImage != nil && (gifImage.Config.Width > gowebp.WebPMaxDimension || gifImage.Config.Height > gowebp.WebPMaxDimension) {
				webPIgnoreURLSet.Push(this.req.URL())
				return
			}
		} else {
			imageData, _, err = image.Decode(reader)
			if imageData != nil {
				var bound = imageData.Bounds()
				if bound.Max.X > gowebp.WebPMaxDimension || bound.Max.Y > gowebp.WebPMaxDimension {
					webPIgnoreURLSet.Push(this.req.URL())
					return
				}
			}
		}

		if err != nil {
			// 发生了错误终止处理
			webPIgnoreURLSet.Push(this.req.URL())
			return
		}

		var f = types.Float32(this.webpQuality)
		if f <= 0 || f > 100 {
			if this.size > (8<<20) || this.size <= 0 {
				f = 30
			} else if this.size > (1 << 20) {
				f = 50
			} else if this.size > (128 << 10) {
				f = 60
			} else {
				f = 75
			}
		}

		if imageData != nil {
			err = gowebp.Encode(this.writer, imageData, &gowebp.Options{
				Lossless: false,
				Quality:  f,
				Exact:    true,
			})
		} else if gifImage != nil {
			var anim = gowebp.NewWebpAnimation(gifImage.Config.Width, gifImage.Config.Height, gifImage.LoopCount)

			anim.WebPAnimEncoderOptions.SetKmin(9)
			anim.WebPAnimEncoderOptions.SetKmax(17)
			var webpConfig = gowebp.NewWebpConfig()
			//webpConfig.SetLossless(1)
			webpConfig.SetQuality(f)

			var timeline = 0
			var lastErr error
			for i, img := range gifImage.Image {
				err = anim.AddFrame(img, timeline, webpConfig)
				if err != nil {
					// 有错误直接跳过
					lastErr = err
					err = nil
				}
				timeline += gifImage.Delay[i] * 10
			}
			if lastErr != nil {
				remotelogs.Error("HTTP_WRITER", "'"+this.req.URL()+"' encode webp failed: "+lastErr.Error())
			}
			err = anim.AddFrame(nil, timeline, webpConfig)

			if err == nil {
				err = anim.Encode(this.writer)
			}

			anim.ReleaseMemory()
		}

		if err != nil && !this.req.canIgnore(err) {
			remotelogs.Error("HTTP_WRITER", "'"+this.req.URL()+"' encode webp failed: "+err.Error())
		}

		if err == nil && webpCacheWriter != nil {
			err = webpCacheWriter.Close()
			if err != nil {
				_ = webpCacheWriter.Discard()
			} else {
				this.cacheStorage.AddToList(&caches.Item{
					Type:       webpCacheWriter.ItemType(),
					Key:        webpCacheWriter.Key(),
					ExpiresAt:  webpCacheWriter.ExpiredAt(),
					StaleAt:    webpCacheWriter.ExpiredAt() + int64(this.calculateStaleLife()),
					HeaderSize: webpCacheWriter.HeaderSize(),
					BodySize:   webpCacheWriter.BodySize(),
					Host:       this.req.ReqHost,
					ServerId:   this.req.ReqServer.Id,
				})
			}
		}
	}
}