Inline Classes

@file:Suppress("EXPERIMENTAL_FEATURE_WARNING")

package de.icks.led.shared

import androidx.annotation.ColorInt
import de.icks.led.util.currentMillisFromMidnight

private const val COMMAND_TYPE_MASK      = 0xF000000_00000000
private const val COMMAND_TYPE_INDEX     = 0x1000000_00000000
private const val COMMAND_TYPE_FILL      = 0x2000000_00000000
private const val COMMAND_TYPE_COLOR     = 0x3000000_00000000

private const val TIMESTAMP_MASK = 0x0FFFFFF_00000000 // Note: 279 minutes as millis is the maximum timestamp
private const val PAYLOAD_MASK   = 0x0000000_FFFFFFFF

private val millisFromMidNight = currentMillisFromMidnight()
private fun maskedTimestamp() = ((System.currentTimeMillis() - millisFromMidNight) shl 32) and TIMESTAMP_MASK

interface LedCommand {
    val encodedCommand: Long
}

interface TimestampCommand: LedCommand {
    /**
     * Millis from midnight
     */
    val timestampMillis get() = (encodedCommand and TIMESTAMP_MASK) shr 32
}

inline class LedIndexCommand(override val encodedCommand: Long) : TimestampCommand {
    constructor( index: Int) : this(COMMAND_TYPE_INDEX or maskedTimestamp() or (PAYLOAD_MASK and index.toLong()))
    val index get() =  (encodedCommand and PAYLOAD_MASK).toInt()
}

inline class LedColorCommand(override val encodedCommand: Long): TimestampCommand {
    constructor(@ColorInt color: Int) : this(COMMAND_TYPE_COLOR or maskedTimestamp() or (PAYLOAD_MASK and color.toLong()))
    val color @ColorInt get() =  (encodedCommand and PAYLOAD_MASK).toInt()
}

inline class LedFillCommand(override val encodedCommand: Long): TimestampCommand {
    constructor() : this(COMMAND_TYPE_FILL or maskedTimestamp())
}

interface LedCommandResolver {
    fun resolveCommand(encodedCommand: Long) {
        when(encodedCommand and COMMAND_TYPE_MASK) {
            COMMAND_TYPE_INDEX -> onIndexCommand(LedIndexCommand(encodedCommand))
            COMMAND_TYPE_FILL -> onFillCommand(LedFillCommand(encodedCommand))
            COMMAND_TYPE_COLOR -> onColorCommand(LedColorCommand(encodedCommand))
        }
    }

    fun onIndexCommand(command: LedIndexCommand) {}
    fun onFillCommand(command: LedFillCommand) {}
    fun onColorCommand(command: LedColorCommand) {}
}