Merge pull request #24 from tillhub/develop

Verifone image printing improvements

Author: djordjeh

print-engine/build.gradle.kts

@@ -84,7 +84,7 @@ afterEvaluate {
             create<MavenPublication>("print-engine") {
                 groupId = "de.tillhub.printengine"
                 artifactId = "print-engine"
-                version = "1.7.0"
+                version = "1.7.1"
 
                 from(components.getByName("release"))
             }

print-engine/src/main/java/de/tillhub/printengine/data/PrinterInfo.kt

@@ -20,7 +20,8 @@ data class PrinterInfo(
 enum class PrintingPaperSpec(val characterCount: Int) {
     /** Printing paper width of 56 mm */
     PAX_PAPER_56MM(32),
-    SUNMI_PAPER_56MM(38)
+    SUNMI_PAPER_56MM(38),
+    VERIFONE_PAPER_58MM(32)
 }
 
 /**

print-engine/src/main/java/de/tillhub/printengine/verifone/VerifonePrintController.kt

@@ -13,6 +13,9 @@ import de.tillhub.printengine.data.PrintingPaperSpec
 import de.tillhub.printengine.data.RawPrinterData
 import de.tillhub.printengine.barcode.BarcodeEncoder
 import de.tillhub.printengine.barcode.BarcodeType
+import de.tillhub.printengine.verifone.VerifoneUtils.FEED_PAPER
+import de.tillhub.printengine.verifone.VerifoneUtils.generateImageHtml
+import de.tillhub.printengine.verifone.VerifoneUtils.monospaceText
 import de.tillhub.printengine.verifone.VerifoneUtils.singleLineCenteredText
 import de.tillhub.printengine.verifone.VerifoneUtils.transformToHtml
 import kotlinx.coroutines.flow.MutableStateFlow
@@ -26,7 +29,7 @@ class VerifonePrintController(
      * If this field is set to false each print command is handled separately.
      * If it is set to true the print commands are grouped and handled when start() is called
      */
-    private val batchPrint: Boolean = true
+    private val batchPrint: Boolean = BATCH_PRINT_DEFAULT
 ) : PrinterController {
 
     private val batchSB = StringBuilder()
@@ -67,17 +70,15 @@ class VerifonePrintController(
 
     override fun observePrinterState(): StateFlow<PrinterState> = printerState
 
-    override fun setFontSize(fontSize: PrintingFontType) {
-        // Not supported
-    }
+    override fun setFontSize(fontSize: PrintingFontType) = Unit // Not supported
 
     override fun printText(text: String) {
         if (batchPrint) {
-            batchSB.append(text).append("\n")
+            batchSB.appendLine(monospaceText(text))
         } else {
             printManager.printString(
                 printListener,
-                transformToHtml(text),
+                transformToHtml(monospaceText(text)),
                 Printer.PRINTER_NO_CUTTER_LINE_FEED
             )
         }
@@ -98,16 +99,16 @@ class VerifonePrintController(
     }
 
     override fun printImage(image: Bitmap) {
-        if (batchPrint && batchSB.isNotEmpty()) {
-            printBatchedString()
+        if (batchPrint) {
+            batchSB.append(generateImageHtml(image))
+        } else {
+            printManager.printBitmap(printListener, image, Printer.PRINTER_NO_CUTTER_LINE_FEED)
         }
-
-        printManager.printBitmap(printListener, image, Printer.PRINTER_NO_CUTTER_LINE_FEED)
     }
 
     override fun feedPaper() {
         if (batchPrint) {
-            batchSB.append("\n\n\n")
+            batchSB.append(FEED_PAPER)
         } else {
             printManager.printString(printListener, "", Printer.PRINTER_NO_CUT)
         }
@@ -121,20 +122,17 @@ class VerifonePrintController(
         }
     }
 
-    override fun setIntensity(intensity: PrintingIntensity) {
-        // Not supported
-    }
+    override fun setIntensity(intensity: PrintingIntensity) = Unit // Not supported
 
     override fun start() {
-        if (batchPrint) {
-            if (batchSB.isNotEmpty()) {
-                printBatchedString()
-            }
-
-            if (useCutter) {
-                printManager.printString(printListener, "", Printer.PRINTER_FULL_CUT)
-            }
+        if (batchPrint && batchSB.isNotEmpty()) {
+            printManager.printString(
+                printListener,
+                transformToHtml(batchSB.toString()),
+                if (useCutter) Printer.PRINTER_FULL_CUT else Printer.PRINTER_NO_CUTTER_LINE_FEED
+            )
 
+            batchSB.clear()
             useCutter = false
         }
     }
@@ -144,25 +142,15 @@ class VerifonePrintController(
             serialNumber = "n/a",
             deviceModel = "Verifone T630c",
             printerVersion = "n/a",
-            printerPaperSpec = PrintingPaperSpec.PAX_PAPER_56MM,
+            printerPaperSpec = PrintingPaperSpec.VERIFONE_PAPER_58MM,
             printingFontType = PrintingFontType.DEFAULT_FONT_SIZE,
             printerHead = "n/a",
             printedDistance = 0,
             serviceVersion = PrinterServiceVersion.Unknown
         )
 
-    private fun printBatchedString() {
-        val payload = batchSB.toString()
-
-        printManager.printString(
-            printListener,
-            transformToHtml(payload),
-            Printer.PRINTER_NO_CUTTER_LINE_FEED
-        )
-        batchSB.clear()
-    }
-
     companion object {
+        private const val BATCH_PRINT_DEFAULT = true
         private const val BARCODE_HEIGHT = 140
         private const val BARCODE_WIDTH = 420
         private const val QR_CODE_SIZE = 420

print-engine/src/main/java/de/tillhub/printengine/verifone/VerifoneUtils.kt

@@ -2,34 +2,32 @@ package de.tillhub.printengine.verifone
 
 import android.graphics.Bitmap
 import android.util.Base64
+import androidx.annotation.VisibleForTesting
 import java.io.ByteArrayOutputStream
 
 object VerifoneUtils {
 
     fun transformToHtml(text: String): String =
-        "<html>" +
-            "<body>" +
-                """<pre style="font-family: monospace; letter-spacing: 0px; font-size: 20px;">""" + "\n" +
-                text +
-                "\n</pre>" +
-            "</body>" +
-        "</html>"
+        "<html><body>$text</body></html>"
+
+    fun monospaceText(text: String): String =
+        "<pre style=\"font-family: monospace; letter-spacing: 0px; font-size: 20px;\">$text</pre>"
 
     fun singleLineCenteredText(text: String): String =
-        "<table style='width:100%' border=\"0\">" +
-            "<tr><td style=\"text-align: center;\">$text</td></tr>" +
-        "</table>"
+        "<div style=\"text-align:center;\">$text</div>"
 
-    fun transformToHtml(image: Bitmap): String =
-        "<tr><td style=\"text-align: center;\">" +
-            "<img src=\"data:image/png;base64, ${ encodeImage(image) }\" alt=\"Red dot\" />" +
-        "</td></tr>"
+    fun generateImageHtml(image: Bitmap): String =
+        "<div style=\"text-align:center;\">" +
+            "<img src=\"data:image/png;base64,${encodeToBase64(image)}\"/>" +
+        "</div>"
 
-    private fun encodeImage(image: Bitmap): String = ByteArrayOutputStream().let { stream ->
-        image.compress(Bitmap.CompressFormat.JPEG, JPEG_QUALITY, stream)
+    @VisibleForTesting
+    fun encodeToBase64(image: Bitmap): String = ByteArrayOutputStream().let { stream ->
+        image.compress(Bitmap.CompressFormat.PNG, PNG_QUALITY, stream)
         val b = stream.toByteArray()
         Base64.encodeToString(b, Base64.DEFAULT)
     }
 
-    private const val JPEG_QUALITY = 100
+    const val FEED_PAPER: String = "<br /><br /><br /><br /><br />"
+    private const val PNG_QUALITY = 100
 }