PrinterAPI.kt

package ru.todaydelivery.android

import android.bluetooth.BluetoothAdapter
import android.bluetooth.BluetoothDevice
import android.bluetooth.BluetoothSocket
import ru.todaydelivery.android.Printer3CottBT.PRINTER_UUID
import java.io.Closeable
import java.io.OutputStream
import java.nio.charset.Charset
import java.util.*
import java.util.concurrent.Executors

/**
 * Well, sorry for no comments here!
 * Still you can send me your question to me@cab404.ru!
 * <p/>
 * Created at 15:49 on 14/11/17
 *
 * @author cab404
 */

/** you can do ternary like `true Q 1 I 0`*/
infix fun <A> Boolean.Q(t: A?): A? = if (this) t else null

infix fun <A> A?.I(t: A): A = this ?: t


object Printer3CottBT {
    val PRINTER_UUID = UUID.fromString("00001101-0000-1000-8000-00805F9B34FB")
    val adapter = BluetoothAdapter.getDefaultAdapter()

    fun start() {
    }

    fun devices(): MutableSet<BluetoothDevice> = adapter.bondedDevices

    fun connect(device: BluetoothDevice): Printer3Cott {
        return Printer3Cott(device)
    }

}


class Printer3Cott(val device: BluetoothDevice) : Closeable {

    private val queue = Executors.newSingleThreadExecutor()

    fun Iterable<Int>.barr() = map(Int::toByte).toByteArray()
    fun OutputStream.write(vararg bytes: Int) = write(bytes.asIterable().barr())

    var socket: BluetoothSocket? = null

    fun reconnect() = device.createRfcommSocketToServiceRecord(PRINTER_UUID).apply { connect() }

    operator fun invoke(exec: Printer3Cott.() -> Unit) {
        queue.execute {
            socket = socket?.let {
                if (it.isConnected) it else null
            } ?: reconnect()
            exec()
        }

    }

    object PrintMode {
        const val FONT_B = 1
        const val BOLD = 8
        const val HIGH = 16
        const val WIDE = 32
        const val UNDERLINE = 128
    }

    object TextAlign {
        const val LEFT = 0
        const val MIDDLE = 1
        const val RIGHT = 2
    }

    object CharsetTable {
        const val PC437 = 0
        const val KATAKANA = 1
        const val PC850 = 2
        const val PC860 = 3
        const val PC863 = 4
        const val PC865 = 5
        const val WEST_EUROPE = 6
        const val GREEK = 7
        const val HEBREW = 8
        const val PC755 = 9
        const val IRAN = 10
        const val WPC1252 = 16
        const val PC866 = 17
        const val PC852 = 18
        const val PC858 = 19
        const val IRAN_II = 20
        const val LATVIAN = 21
    }

    fun setCharTable(charset: Int) =
            socket?.outputStream?.write(27, 116, charset)

    fun println(text: String, feedLines: Int = 0, charset: String = "IBM866") =
            socket?.outputStream?.write(text.toByteArray(Charset.forName(charset)) + listOf(27, 100, feedLines).barr())

    fun print(text: String, charset: String = "IBM866") =
            socket?.outputStream?.write(text.toByteArray(Charset.forName(charset)) + listOf(10, 0).barr())

    fun setPrintMode(flags: Int) =
            socket?.outputStream?.write(27, 33, flags)

    fun setInverted(enabled: Boolean) =
            socket?.outputStream?.write(27, 123, enabled Q 1 I 0)

    fun setTextAlign(align: Int) =
            socket?.outputStream?.write(27, 97, align)

    fun setBarcodeHeight(pixels: Int) =
            socket?.outputStream?.write(29, 104, pixels)

    fun beep(on: Int, off: Int = 0, pin: Int = 0) =
            socket?.outputStream?.write(27, 112, pin, on, off)

    fun resetPrinter() =
            socket?.outputStream?.write(27, 64)

    fun flush() =
            socket?.outputStream?.flush()

    override fun close() {
        socket?.close()
    }

}