131 lines
4.1 KiB
Go
131 lines
4.1 KiB
Go
package qrcode
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import (
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"strconv"
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"github.com/makiuchi-d/gozxing"
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"github.com/makiuchi-d/gozxing/qrcode/decoder"
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"github.com/makiuchi-d/gozxing/qrcode/encoder"
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)
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const (
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qrcodeWriter_QUIET_ZONE_SIZE = 4
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)
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type QRCodeWriter struct{}
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func NewQRCodeWriter() *QRCodeWriter {
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return &QRCodeWriter{}
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}
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func (this *QRCodeWriter) EncodeWithoutHint(
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contents string, format gozxing.BarcodeFormat, width, height int) (*gozxing.BitMatrix, error) {
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return this.Encode(contents, format, width, height, nil)
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}
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func (this *QRCodeWriter) Encode(
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contents string, format gozxing.BarcodeFormat, width, height int,
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hints map[gozxing.EncodeHintType]interface{}) (*gozxing.BitMatrix, error) {
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if len(contents) == 0 {
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return nil, gozxing.NewWriterException("IllegalArgumentException: Found empty contents")
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}
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if format != gozxing.BarcodeFormat_QR_CODE {
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return nil, gozxing.NewWriterException(
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"IllegalArgumentException: Can only encode QR_CODE, but got %v", format)
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}
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if width < 0 || height < 0 {
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return nil, gozxing.NewWriterException(
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"IllegalArgumentException: Requested dimensions are too small: %vx%v", width, height)
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}
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errorCorrectionLevel := decoder.ErrorCorrectionLevel_L
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quietZone := qrcodeWriter_QUIET_ZONE_SIZE
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if hints != nil {
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if ec, ok := hints[gozxing.EncodeHintType_ERROR_CORRECTION]; ok {
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if ecl, ok := ec.(decoder.ErrorCorrectionLevel); ok {
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errorCorrectionLevel = ecl
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} else if str, ok := ec.(string); ok {
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ecl, e := decoder.ErrorCorrectionLevel_ValueOf(str)
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if e != nil {
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return nil, gozxing.NewWriterException("EncodeHintType_ERROR_CORRECTION: %w", e)
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}
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errorCorrectionLevel = ecl
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} else {
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return nil, gozxing.NewWriterException(
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"IllegalArgumentException: EncodeHintType_ERROR_CORRECTION %v", ec)
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}
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}
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if m, ok := hints[gozxing.EncodeHintType_MARGIN]; ok {
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if qz, ok := m.(int); ok {
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quietZone = qz
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} else if str, ok := m.(string); ok {
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qz, e := strconv.Atoi(str)
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if e != nil {
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return nil, gozxing.NewWriterException("EncodeHintType_MARGIN = \"%v\": %w", m, e)
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}
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quietZone = qz
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} else {
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return nil, gozxing.NewWriterException(
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"IllegalArgumentException: EncodeHintType_MARGIN %v", m)
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}
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}
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}
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code, e := encoder.Encoder_encode(contents, errorCorrectionLevel, hints)
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if e != nil {
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return nil, e
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}
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return renderResult(code, width, height, quietZone)
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}
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// renderResult Note that the input matrix uses 0 == white, 1 == black, while the output matrix uses
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// 0 == black, 255 == white (i.e. an 8 bit greyscale bitmap).
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func renderResult(code *encoder.QRCode, width, height, quietZone int) (*gozxing.BitMatrix, error) {
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input := code.GetMatrix()
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if input == nil {
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return nil, gozxing.NewWriterException("IllegalStateException")
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}
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inputWidth := input.GetWidth()
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inputHeight := input.GetHeight()
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qrWidth := inputWidth + (quietZone * 2)
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qrHeight := inputHeight + (quietZone * 2)
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outputWidth := qrWidth
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if outputWidth < width {
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outputWidth = width
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}
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outputHeight := qrHeight
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if outputHeight < height {
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outputHeight = height
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}
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multiple := outputWidth / qrWidth
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if h := outputHeight / qrHeight; multiple > h {
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multiple = h
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}
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// Padding includes both the quiet zone and the extra white pixels to accommodate the requested
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// dimensions. For example, if input is 25x25 the QR will be 33x33 including the quiet zone.
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// If the requested size is 200x160, the multiple will be 4, for a QR of 132x132. These will
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// handle all the padding from 100x100 (the actual QR) up to 200x160.
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leftPadding := (outputWidth - (inputWidth * multiple)) / 2
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topPadding := (outputHeight - (inputHeight * multiple)) / 2
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output, e := gozxing.NewBitMatrix(outputWidth, outputHeight)
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if e != nil {
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return nil, gozxing.WrapWriterException(e)
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}
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for inputY, outputY := 0, topPadding; inputY < inputHeight; inputY, outputY = inputY+1, outputY+multiple {
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// Write the contents of this row of the barcode
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for inputX, outputX := 0, leftPadding; inputX < inputWidth; inputX, outputX = inputX+1, outputX+multiple {
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if input.Get(inputX, inputY) == 1 {
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output.SetRegion(outputX, outputY, multiple, multiple)
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}
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}
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}
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return output, nil
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}
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