image/app/controller/image.go

package controller

import (
	"encoding/hex"
	"errors"
	"github.com/gin-gonic/gin"
	"github.com/skip2/go-qrcode"
	"gopkg.in/gographics/imagick.v3/imagick"
	"image/color"
	"img/app/common"
	"img/app/config"
	"log"
	"net/url"
	"os"
	"path/filepath"
	"strconv"
	"strings"
)

type Image struct {
}

type argsQr struct {
	Text   string `form:"text"`
	Size   int    `form:"size"`
	Fcolor string `form:"fcolor"`
	Bcolor string `form:"bcolor"`
}

// Qr 生成二维码
func (i *Image) Qr(c *gin.Context) {
	args := argsQr{}
	if err := c.ShouldBindQuery(&args); err != nil {
	}
	log.Println(args)
	if args.Text == "" {
		args.Text = config.Config.Qr.DefaultText
	}
	if args.Size < 10 || args.Size > 1000 {
		args.Size = config.Config.Qr.DefaultSize
	}
	if args.Fcolor == "" {
		args.Fcolor = config.Config.Qr.DefaultFcolor
	}
	if args.Bcolor == "" {
		args.Bcolor = config.Config.Qr.DefaultBcolor
	}
	fcolor, _ := hex.DecodeString(args.Fcolor)
	if len(fcolor) != 3 {
		fcolor = []byte{255, 255, 255}
	}
	bcolor, _ := hex.DecodeString(args.Bcolor)
	if len(bcolor) != 3 {
		bcolor = []byte{255, 255, 255}
	}
	qrCode, _ := qrcode.New(args.Text, qrcode.Medium)
	qrCode.ForegroundColor = color.RGBA{fcolor[0], fcolor[1], fcolor[2], 255}
	qrCode.BackgroundColor = color.RGBA{bcolor[0], bcolor[1], bcolor[2], 255}
	buff, _ := qrCode.PNG(args.Size)
	_, _ = c.Writer.Write(buff)
}

type argsThumb struct {
	W float64
	H float64
}

// Thumb 生成缩略图
func (i *Image) Thumb(c *gin.Context) {
	urls := strings.Split(c.Request.URL.String(), "@")
	filename := filepath.Join(config.Config.Image.Root, config.Config.Image.Source, urls[0])
	saveName := filepath.Join(config.Config.Image.Root, config.Config.Image.Thumb, c.Request.URL.String())
	if common.FileExists(saveName) {
		c.File(saveName)
		return
	}
	args := argsThumb{}
	if len(urls) > 1 {
		query, _ := url.ParseQuery(urls[1])
		args.W, _ = strconv.ParseFloat(query.Get("w"), 64)
		args.H, _ = strconv.ParseFloat(query.Get("h"), 64)
	}

	//创建新的MagicWand
	mw := imagick.NewMagickWand()
	//读取文件
	err := mw.ReadImage(filename)
	if err != nil {
		return
	}

	if args.W != 0 || args.H != 0 {
		err := i.reset(args.W, args.H, mw)
		if err != nil {
			c.File(filename)
			return
		}
	}

	//改变图片质量
	err = mw.SetImageCompressionQuality(85)
	if err != nil {
		return
	}
	//导出图片
	if err := os.MkdirAll(filepath.Dir(saveName), os.ModePerm); err != nil {
		return
	}
	err = mw.WriteImage(saveName)
	c.File(saveName)
}

func (i *Image) reset(w float64, h float64, mw *imagick.MagickWand) error {
	width := float64(mw.GetImageWidth())
	height := float64(mw.GetImageHeight())
	if w >= width || h >= height {
		return errors.New("can't max")
	}
	var newH, newW, crop_x, crop_y float64
	if w == 0 {
		newH = h
		newW = width / (height / h)
	} else if h == 0 {
		newW = w
		newH = height / (width / w)
	} else {
		if width/w < height/h {
			newW = w
			newH = height / (width / w)
			crop_x = 0
			crop_y = (newH - h) / 2
		} else {
			newH = h
			newW = width / (height / h)
			crop_x = (newW - w) / 2
			crop_y = 0
		}
	}
	_ = mw.ResizeImage(uint(newW), uint(newH), imagick.FILTER_LANCZOS)
	if w != 0 && h != 0 {
		_ = mw.CropImage(uint(w), uint(h), int(crop_x), int(crop_y))
	}
	return nil
}