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package base64Captcha
import (
"image/color"
"math/rand"
"strings"
"github.com/golang/freetype/truetype"
)
//DriverChinese is a driver of unicode Chinese characters.
type DriverChinese struct {
//Height png height in pixel.
Height int
//Width Captcha png width in pixel.
Width int
//NoiseCount text noise count.
NoiseCount int
//ShowLineOptions := OptionShowHollowLine | OptionShowSlimeLine | OptionShowSineLine .
ShowLineOptions int
//Length random string length.
Length int
//Source is a unicode which is the rand string from.
Source string
//BgColor captcha image background color (optional)
BgColor *color.RGBA
//fontsStorage font storage (optional)
fontsStorage FontsStorage
//Fonts loads by name see fonts.go's comment
Fonts []string
fontsArray []*truetype.Font
}
//NewDriverChinese creates a driver of Chinese characters
func NewDriverChinese(height int, width int, noiseCount int, showLineOptions int, length int, source string, bgColor *color.RGBA, fontsStorage FontsStorage, fonts []string) *DriverChinese {
if fontsStorage == nil {
fontsStorage = DefaultEmbeddedFonts
}
tfs := []*truetype.Font{}
for _, fff := range fonts {
tf := fontsStorage.LoadFontByName("fonts/" + fff)
tfs = append(tfs, tf)
}
if len(tfs) == 0 {
tfs = fontsAll
}
return &DriverChinese{Height: height, Width: width, NoiseCount: noiseCount, ShowLineOptions: showLineOptions, Length: length, Source: source, BgColor: bgColor, fontsStorage: fontsStorage, fontsArray: tfs}
}
//ConvertFonts loads fonts by names
func (d *DriverChinese) ConvertFonts() *DriverChinese {
if d.fontsStorage == nil {
d.fontsStorage = DefaultEmbeddedFonts
}
tfs := []*truetype.Font{}
for _, fff := range d.Fonts {
tf := d.fontsStorage.LoadFontByName("fonts/" + fff)
tfs = append(tfs, tf)
}
if len(tfs) == 0 {
tfs = fontsAll
}
d.fontsArray = tfs
return d
}
//GenerateIdQuestionAnswer generates captcha content and its answer
func (d *DriverChinese) GenerateIdQuestionAnswer() (id, content, answer string) {
id = RandomId()
ss := strings.Split(d.Source, ",")
length := len(ss)
if length == 1 {
c := RandText(d.Length, ss[0])
return id, c, c
}
if length <= d.Length {
c := RandText(d.Length, TxtNumbers+TxtAlphabet)
return id, c, c
}
res := make([]string, d.Length)
for k := range res {
res[k] = ss[rand.Intn(length)]
}
content = strings.Join(res, "")
return id, content, content
}
//DrawCaptcha generates captcha item(image)
func (d *DriverChinese) DrawCaptcha(content string) (item Item, err error) {
var bgc color.RGBA
if d.BgColor != nil {
bgc = *d.BgColor
} else {
bgc = RandLightColor()
}
itemChar := NewItemChar(d.Width, d.Height, bgc)
//draw hollow line
if d.ShowLineOptions&OptionShowHollowLine == OptionShowHollowLine {
itemChar.drawHollowLine()
}
//draw slime line
if d.ShowLineOptions&OptionShowSlimeLine == OptionShowSlimeLine {
itemChar.drawSlimLine(3)
}
//draw sine line
if d.ShowLineOptions&OptionShowSineLine == OptionShowSineLine {
itemChar.drawSineLine()
}
//draw noise
if d.NoiseCount > 0 {
source := TxtNumbers + TxtAlphabet + ",.[]<>"
noise := RandText(d.NoiseCount, strings.Repeat(source, d.NoiseCount))
err = itemChar.drawNoise(noise, d.fontsArray)
if err != nil {
return
}
}
//draw content
err = itemChar.drawText(content, d.fontsArray)
if err != nil {
return
}
return itemChar, nil
}