1 files changed, 155 insertions, 0 deletions
diff --git a/merchant-terminal/src/main/java/net/taler/merchantpos/Utils.kt b/merchant-terminal/src/main/java/net/taler/merchantpos/Utils.kt
new file mode 100644
index 0000000..a0c30d6
--- /dev/null
+++ b/merchant-terminal/src/main/java/net/taler/merchantpos/Utils.kt
@@ -0,0 +1,155 @@
+/*
+ * This file is part of GNU Taler
+ * (C) 2020 Taler Systems S.A.
+ *
+ * GNU Taler is free software; you can redistribute it and/or modify it under the
+ * terms of the GNU General Public License as published by the Free Software
+ * Foundation; either version 3, or (at your option) any later version.
+ *
+ * GNU Taler is distributed in the hope that it will be useful, but WITHOUT ANY
+ * WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+ * A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * GNU Taler; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+ */
+
+package net.taler.merchantpos
+
+import android.content.Context
+import android.text.format.DateUtils.DAY_IN_MILLIS
+import android.text.format.DateUtils.FORMAT_ABBREV_MONTH
+import android.text.format.DateUtils.FORMAT_ABBREV_RELATIVE
+import android.text.format.DateUtils.FORMAT_NO_YEAR
+import android.text.format.DateUtils.FORMAT_SHOW_DATE
+import android.text.format.DateUtils.FORMAT_SHOW_TIME
+import android.text.format.DateUtils.MINUTE_IN_MILLIS
+import android.text.format.DateUtils.formatDateTime
+import android.text.format.DateUtils.getRelativeTimeSpanString
+import android.view.View
+import android.view.View.INVISIBLE
+import android.view.View.VISIBLE
+import androidx.annotation.StringRes
+import androidx.fragment.app.Fragment
+import androidx.lifecycle.LiveData
+import androidx.lifecycle.MediatorLiveData
+import androidx.lifecycle.Observer
+import androidx.navigation.NavController
+import androidx.navigation.NavDirections
+import androidx.navigation.fragment.findNavController
+import com.google.android.material.snackbar.BaseTransientBottomBar.ANIMATION_MODE_FADE
+import com.google.android.material.snackbar.BaseTransientBottomBar.Duration
+import com.google.android.material.snackbar.Snackbar.make
+
+object Utils {
+
+    private const val HEX_CHARS = "0123456789ABCDEF"
+
+    fun hexStringToByteArray(data: String): ByteArray {
+        val result = ByteArray(data.length / 2)
+
+        for (i in data.indices step 2) {
+            val firstIndex = HEX_CHARS.indexOf(data[i])
+            val secondIndex = HEX_CHARS.indexOf(data[i + 1])
+
+            val octet = firstIndex.shl(4).or(secondIndex)
+            result[i.shr(1)] = octet.toByte()
+        }
+        return result
+    }
+
+
+    private val HEX_CHARS_ARRAY = HEX_CHARS.toCharArray()
+
+    @Suppress("unused")
+    fun toHex(byteArray: ByteArray): String {
+        val result = StringBuffer()
+
+        byteArray.forEach {
+            val octet = it.toInt()
+            val firstIndex = (octet and 0xF0).ushr(4)
+            val secondIndex = octet and 0x0F
+            result.append(HEX_CHARS_ARRAY[firstIndex])
+            result.append(HEX_CHARS_ARRAY[secondIndex])
+        }
+        return result.toString()
+    }
+
+}
+
+fun View.fadeIn(endAction: () -> Unit = {}) {
+    if (visibility == VISIBLE) return
+    alpha = 0f
+    visibility = VISIBLE
+    animate().alpha(1f).withEndAction {
+        if (context != null) endAction.invoke()
+    }.start()
+}
+
+fun View.fadeOut(endAction: () -> Unit = {}) {
+    if (visibility == INVISIBLE) return
+    animate().alpha(0f).withEndAction {
+        if (context == null) return@withEndAction
+        visibility = INVISIBLE
+        alpha = 1f
+        endAction.invoke()
+    }.start()
+}
+
+fun topSnackbar(view: View, text: CharSequence, @Duration duration: Int) {
+    make(view, text, duration)
+        .setAnimationMode(ANIMATION_MODE_FADE)
+        .setAnchorView(R.id.navHostFragment)
+        .show()
+}
+
+fun topSnackbar(view: View, @StringRes resId: Int, @Duration duration: Int) {
+    topSnackbar(view, view.resources.getText(resId), duration)
+}
+
+fun NavDirections.navigate(nav: NavController) = nav.navigate(this)
+
+fun Fragment.navigate(directions: NavDirections) = findNavController().navigate(directions)
+
+fun Long.toRelativeTime(context: Context): CharSequence {
+    val now = System.currentTimeMillis()
+    return if (now - this > DAY_IN_MILLIS * 2) {
+        val flags = FORMAT_SHOW_TIME or FORMAT_SHOW_DATE or FORMAT_ABBREV_MONTH or FORMAT_NO_YEAR
+        formatDateTime(context, this, flags)
+    } else getRelativeTimeSpanString(this, now, MINUTE_IN_MILLIS, FORMAT_ABBREV_RELATIVE)
+}
+
+class CombinedLiveData<T, K, S>(
+    source1: LiveData<T>,
+    source2: LiveData<K>,
+    private val combine: (data1: T?, data2: K?) -> S
+) : MediatorLiveData<S>() {
+
+    private var data1: T? = null
+    private var data2: K? = null
+
+    init {
+        super.addSource(source1) { t ->
+            data1 = t
+            value = combine(data1, data2)
+        }
+        super.addSource(source2) { k ->
+            data2 = k
+            value = combine(data1, data2)
+        }
+    }
+
+    override fun <S : Any?> addSource(source: LiveData<S>, onChanged: Observer<in S>) {
+        throw UnsupportedOperationException()
+    }
+
+    override fun <T : Any?> removeSource(toRemote: LiveData<T>) {
+        throw UnsupportedOperationException()
+    }
+}
+
+/**
+ * Use this with 'when' expressions when you need it to handle all possibilities/branches.
+ */
+val <T> T.exhaustive: T
+    get() = this