Add setting error correction for AZTEC/PDF417 too

Because ZXing C++ supports setting an error correction level for
these formats too.

app/src/main/kotlin/de/markusfisch/android/binaryeye/fragment/EncodeFragment.kt

@@ -26,7 +26,7 @@ class EncodeFragment : Fragment() {
 	private lateinit var sizeBarView: SeekBar
 	private lateinit var contentView: EditText
 
-	private val writers = arrayListOf(
+	private val formats = arrayListOf(
 		Format.AZTEC,
 		Format.CODABAR,
 		Format.CODE_39,
@@ -58,7 +58,7 @@ class EncodeFragment : Fragment() {
 		val formatAdapter = ArrayAdapter(
 			ac,
 			android.R.layout.simple_spinner_item,
-			writers.map { prettifyFormatName(it.name) }
+			formats.map { prettifyFormatName(it.name) }
 		)
 		formatAdapter.setDropDownViewResource(
 			android.R.layout.simple_spinner_dropdown_item
@@ -71,16 +71,28 @@ class EncodeFragment : Fragment() {
 				position: Int,
 				id: Long
 			) {
-				val ecVisibility = if (
-					writers[position] == Format.QR_CODE
-				) View.VISIBLE else View.GONE
-				ecLabel.visibility = ecVisibility
-				ecSpinner.visibility = ecVisibility
-				val colorsVisibility = if (
-					writers[position].canBeInverted()
-				) View.VISIBLE else View.GONE
-				colorsLabel.visibility = colorsVisibility
-				colorsSpinner.visibility = colorsVisibility
+				val format = formats[position]
+				val arrayId = when (format) {
+					Format.AZTEC -> R.array.aztec_error_correction_levels
+					Format.QR_CODE -> R.array.qr_error_correction_levels
+					Format.PDF_417 -> R.array.pdf417_error_correction_levels
+					else -> 0
+				}
+				if (arrayId > 0) {
+					ecSpinner.setEntries(arrayId)
+					val idx = format.unpackEcLevel(
+						prefs.indexOfLastSelectedEcLevel
+					)
+					if (idx < ecSpinner.adapter.count) {
+						ecSpinner.setSelection(idx)
+					}
+					true
+				} else {
+					false
+				}.setVisibility(ecLabel, ecSpinner)
+				format.canBeInverted().setVisibility(
+					colorsLabel, colorsSpinner
+				)
 			}
 
 			override fun onNothingSelected(parentView: AdapterView<*>?) {}
@@ -88,6 +100,22 @@ class EncodeFragment : Fragment() {
 
 		ecLabel = view.findViewById(R.id.error_correction_label)
 		ecSpinner = view.findViewById(R.id.error_correction_level)
+		ecSpinner.onItemSelectedListener = object : AdapterView.OnItemSelectedListener {
+			override fun onItemSelected(
+				parentView: AdapterView<*>?,
+				selectedItemView: View?,
+				position: Int,
+				id: Long
+			) {
+				val format = formats[formatView.selectedItemPosition]
+				prefs.indexOfLastSelectedEcLevel = format.packEcLevel(
+					prefs.indexOfLastSelectedEcLevel,
+					position
+				)
+			}
+
+			override fun onNothingSelected(parentView: AdapterView<*>?) {}
+		}
 
 		colorsLabel = view.findViewById(R.id.colors_label)
 		colorsSpinner = view.findViewById(R.id.colors)
@@ -106,7 +134,7 @@ class EncodeFragment : Fragment() {
 		val barcodeFormat = args?.getString(FORMAT)
 		if (barcodeFormat != null) {
 			formatView.setSelection(
-				writers.indexOf(barcodeFormat.toFormat())
+				formats.indexOf(barcodeFormat.toFormat())
 			)
 		} else if (state == null) {
 			formatView.post {
@@ -136,14 +164,14 @@ class EncodeFragment : Fragment() {
 			return
 		}
 		hideSoftKeyboard(contentView)
-		val writer = writers[formatView.selectedItemPosition]
+		val format = formats[formatView.selectedItemPosition]
 		fragmentManager?.addFragment(
 			BarcodeFragment.newInstance(
 				content,
-				writer,
+				format,
 				getSize(sizeBarView.progress),
-				(ecSpinner.selectedItemPosition + 1) * 2,
-				if (writer.canBeInverted()) {
+				format.getErrorCorrectionLevel(ecSpinner.selectedItemPosition),
+				if (format.canBeInverted()) {
 					colorsSpinner.selectedItemPosition
 				} else 0
 			)
@@ -173,8 +201,6 @@ class EncodeFragment : Fragment() {
 		sizeView.text = getString(R.string.width_by_height, size, size)
 	}
 
-	private fun getSize(power: Int) = 128 * (power + 1)
-
 	companion object {
 		private const val CONTENT = "content"
 		private const val FORMAT = "format"
@@ -193,6 +219,28 @@ class EncodeFragment : Fragment() {
 	}
 }
 
+private fun Boolean.setVisibility(vararg views: View) {
+	val visibility = if (this) View.VISIBLE else View.GONE
+	for (view in views) {
+		view.visibility = visibility
+	}
+}
+
+private fun Format.packEcLevel(packed: Int, level: Int): Int {
+	val s = ecLevelShift()
+	return (level shl s) or (packed and (15 shl s).inv())
+}
+
+private fun Format.unpackEcLevel(packed: Int) =
+	(packed shr ecLevelShift()) and 15
+
+private fun Format.ecLevelShift() = when (this) {
+	Format.AZTEC -> 0
+	Format.QR_CODE -> 4
+	Format.PDF_417 -> 8
+	else -> throw IllegalArgumentException("$this does not have error levels")
+}
+
 private fun Format.canBeInverted() = when (this) {
 	Format.AZTEC,
 	Format.DATA_MATRIX,
@@ -205,3 +253,23 @@ private fun String.toFormat(default: Format = Format.QR_CODE): Format = try {
 } catch (_: IllegalArgumentException) {
 	default
 }
+
+private fun Format.getErrorCorrectionLevel(position: Int) = when (this) {
+	Format.AZTEC -> position
+	Format.QR_CODE -> (position + 1) * 2
+	Format.PDF_417 -> position
+	else -> 0
+}.coerceIn(0, 8)
+
+private fun Spinner.setEntries(resId: Int) = ArrayAdapter.createFromResource(
+	this.context,
+	resId,
+	android.R.layout.simple_spinner_item
+).also { aa ->
+	aa.setDropDownViewResource(
+		android.R.layout.simple_spinner_dropdown_item
+	)
+	adapter = aa
+}
+
+private fun getSize(power: Int) = 128 * (power + 1)

app/src/main/kotlin/de/markusfisch/android/binaryeye/preference/Preferences.kt

@@ -175,6 +175,11 @@ class Preferences {
 			apply(INDEX_OF_LAST_SELECTED_FORMAT, value)
 			field = value
 		}
+	var indexOfLastSelectedEcLevel: Int = 0
+		set(value) {
+			apply(INDEX_OF_LAST_SELECTED_EC_LEVEL, value)
+			field = value
+		}
 	var freeRotation = true
 		set(value) {
 			apply(FREE_ROTATION, value)
@@ -262,6 +267,10 @@ class Preferences {
 			INDEX_OF_LAST_SELECTED_FORMAT,
 			indexOfLastSelectedFormat
 		)
+		indexOfLastSelectedEcLevel = preferences.getInt(
+			INDEX_OF_LAST_SELECTED_EC_LEVEL,
+			indexOfLastSelectedEcLevel
+		)
 		freeRotation = preferences.getBoolean(FREE_ROTATION, freeRotation)
 	}
 
@@ -327,6 +336,7 @@ class Preferences {
 		private const val SEND_SCAN_TYPE = "send_scan_type"
 		private const val CUSTOM_LOCALE = "custom_locale"
 		private const val INDEX_OF_LAST_SELECTED_FORMAT = "index_of_last_selected_format"
+		private const val INDEX_OF_LAST_SELECTED_EC_LEVEL = "index_of_last_selected_ec_level"
 		private const val FREE_ROTATION = "free_rotation"
 	}
 }

app/src/main/res/layout/fragment_encode.xml

@@ -33,8 +33,7 @@
 				android:id="@+id/error_correction_level"
 				android:layout_width="match_parent"
 				android:layout_height="wrap_content"
-				android:layout_marginBottom="16dp"
-				android:entries="@array/error_correction_levels"/>
+				android:layout_marginBottom="16dp"/>
 			<TextView
 				android:id="@+id/colors_label"
 				android:layout_width="match_parent"

app/src/main/res/values/aztec_error_correction_levels.xml

@@ -0,0 +1,13 @@
+<resources>
+	<string-array name="aztec_error_correction_levels">
+		<item>0%</item>
+		<item>12.5%</item>
+		<item>25%</item>
+		<item>37.5%</item>
+		<item>50%</item>
+		<item>62.5%</item>
+		<item>75%</item>
+		<item>87.5%</item>
+		<item>100%</item>
+	</string-array>
+</resources>

app/src/main/res/values/pdf417_error_correction_levels.xml

@@ -0,0 +1,13 @@
+<resources>
+	<string-array name="pdf417_error_correction_levels">
+		<item>0</item>
+		<item>1</item>
+		<item>2</item>
+		<item>3</item>
+		<item>4</item>
+		<item>5</item>
+		<item>6</item>
+		<item>7</item>
+		<item>8</item>
+	</string-array>
+</resources>

app/src/main/res/values/qr_error_correction_levels.xml

@@ -1,5 +1,5 @@
 <resources>
-	<string-array name="error_correction_levels">
+	<string-array name="qr_error_correction_levels">
 		<item>@string/error_correction_level_l</item>
 		<item>@string/error_correction_level_m</item>
 		<item>@string/error_correction_level_q</item>