/**
 * Utils.kt
 *
 * Copyright (C) 2011 Eric Butler
 * Copyright (C) 2019  <seil0@mosad.xyz>
 *
 * Authors:
 * Eric Butler <eric@codebutler.com>
 *
 * This program 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 of the License, or
 * (at your option) any later version.
 *
 * This program 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 this program.  If not, see <http://www.gnu.org/licenses/>.
 */

package com.codebutler.farebot

import android.app.Activity
import android.app.AlertDialog
import android.util.Log
import android.view.WindowManager
import com.codebutler.farebot.card.desfire.DesfireException
import com.codebutler.farebot.card.desfire.DesfireFileSettings
import com.codebutler.farebot.card.desfire.DesfireProtocol
import org.w3c.dom.Node
import java.io.StringWriter
import javax.xml.transform.OutputKeys
import javax.xml.transform.TransformerFactory
import javax.xml.transform.dom.DOMSource
import javax.xml.transform.stream.StreamResult
import kotlin.experimental.and

class Utils {

    companion object {
        private val TAG = Utils::class.java.name

        @Suppress("unused")
        fun showError(activity: Activity, ex: Exception) {
            Log.e(activity.javaClass.name, ex.message, ex)
            AlertDialog.Builder(activity)
                .setMessage(getErrorMessage(ex))
                .show()
        }

        @Suppress("unused")
        fun showErrorAndFinish(activity: Activity, ex: Exception) {
            try {
                Log.e(activity.javaClass.name, getErrorMessage(ex))
                ex.printStackTrace()

                AlertDialog.Builder(activity)
                    .setMessage(getErrorMessage(ex))
                    .setCancelable(false)
                    .setPositiveButton(android.R.string.ok) { _, _ -> activity.finish() }
                    .show()
            } catch (unused: WindowManager.BadTokenException) {
                /* Ignore... happens if the activity was destroyed */
            }

        }

        @Throws(Exception::class)
        fun getHexString(b: ByteArray): String {
            var result = ""
            for (i in b.indices) {
                result += ((b[i] and 0xff.toByte()) + 0x100).toString(16).substring(1)
            }
            return result
        }

        @Suppress("unused")
        fun getHexString(b: ByteArray, defaultResult: String): String {
            return try {
                getHexString(b)
            } catch (ex: Exception) {
                defaultResult
            }

        }

        @Suppress("unused")
        fun hexStringToByteArray(s: String): ByteArray {
            if (s.length % 2 != 0) {
                throw IllegalArgumentException("Bad input string: $s")
            }

            val len = s.length
            val data = ByteArray(len / 2)
            var i = 0
            while (i < len) {
                data[i / 2] = ((Character.digit(s[i], 16) shl 4) + Character.digit(s[i + 1], 16)).toByte()
                i += 2
            }
            return data
        }

        @JvmOverloads
        fun byteArrayToInt(b: ByteArray, offset: Int = 0, length: Int = b.size): Int {
            return byteArrayToLong(b, offset, length).toInt()
        }

        fun byteArrayToLong(b: ByteArray, offset: Int, length: Int): Long {
            if (b.size < length)
                throw IllegalArgumentException("length must be less than or equal to b.length")

            var value: Long = 0
            for (i in 0 until length) {
                val shift = (length - 1 - i) * 8
                value += ((b[i + offset].toInt() and 0x000000FF).toLong() shl shift)
            }

            return value
        }

        @Suppress("unused")
        fun byteArraySlice(b: ByteArray, offset: Int, length: Int): ByteArray {
            val ret = ByteArray(length)
            for (i in 0 until length)
                ret[i] = b[offset + i]
            return ret
        }

        @Suppress("unused")
        @Throws(Exception::class)
        fun xmlNodeToString(node: Node): String {
            // The amount of code required to do simple things in Java is incredible.
            val source = DOMSource(node)
            val stringWriter = StringWriter()
            val result = StreamResult(stringWriter)
            val factory = TransformerFactory.newInstance()
            val transformer = factory.newTransformer()
            transformer.setOutputProperty(OutputKeys.INDENT, "yes")
            transformer.setOutputProperty("{http://xml.apache.org/xslt}indent-amount", "2")
            transformer.uriResolver = null
            transformer.transform(source, result)
            return stringWriter.buffer.toString()
        }

        fun getErrorMessage(ex: Throwable): String {
            var errorMessage: String? = ex.localizedMessage
            if (errorMessage == null)
                errorMessage = ex.message
            if (errorMessage == null)
                errorMessage = ex.toString()

            if (ex.cause != null) {
                var causeMessage: String? = ex.cause!!.localizedMessage
                if (causeMessage == null)
                    causeMessage = ex.cause!!.message
                if (causeMessage == null)
                    causeMessage = ex.cause.toString()

                errorMessage += ": $causeMessage"
            }

            return errorMessage
        }

        @Suppress("unused")
        fun <T> findInList(list: List<T>, matcher: Matcher<T>): T? {
            for (item in list) {
                if (matcher.matches(item)) {
                    return item
                }
            }
            return null
        }

        interface Matcher<T> {
            fun matches(t: T): Boolean
        }

        fun selectAppFile(tag: DesfireProtocol, appID: Int, fileID: Int): DesfireFileSettings? {
            try {
                tag.selectApp(appID)
            } catch (e: DesfireException) {
                Log.w(TAG, "App not found")
                return null
            }

            return try {
                tag.getFileSettings(fileID)
            } catch (e: DesfireException) {
                Log.w(TAG, "File not found")
                null
            }

        }

        fun arrayContains(arr: IntArray, item: Int): Boolean {
            for (i in arr)
                if (i == item)
                    return true
            return false
        }

        @Suppress("unused")
        fun containsAppFile(tag: DesfireProtocol, appID: Int, fileID: Int): Boolean {
            try {
                tag.selectApp(appID)
            } catch (e: DesfireException) {
                Log.w(TAG, "App not found")
                Log.w(TAG, e)
                return false
            }

            return try {
                arrayContains(tag.fileList, fileID)
            } catch (e: DesfireException) {
                Log.w(TAG, "File not found")
                Log.w(TAG, e)
                false
            }

        }
    }

}