HC05AC-CTRL/src/main/java/io/gitlab/jfronny/hc05ac/InputActivity.kt

package io.gitlab.jfronny.hc05ac

import android.os.Bundle
import android.view.MotionEvent
import android.widget.TextView
import androidx.appcompat.widget.LinearLayoutCompat
import io.gitlab.jfronny.hc05ac.util.Action
import io.gitlab.jfronny.hc05ac.util.BaseActivity
import io.gitlab.jfronny.hc05ac.util.clamp
import io.gitlab.jfronny.hc05ac.util.jAction

/**
 * Activity that divides the screen into two halves, each serving as an input controller.
 * Implementations define a send function which is called for every update.
 */
abstract class InputActivity : BaseActivity() {
    private var root: LinearLayoutCompat? = null
    private var leftView: TextView? = null
    private var rightView: TextView? = null
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)
        setContentView(R.layout.activity_main)
        root = findViewById(R.id.root)
        leftView = findViewById(R.id.left)
        rightView = findViewById(R.id.right)
    }

    override fun onTouchEvent(event: MotionEvent?): Boolean {
        if (event != null) {
            if (event.x > root!!.width / 2) right(event.y, root!!.height.toFloat(), event.jAction)
            else left(event.y, root!!.height.toFloat(), event.jAction)
        }
        return false
    }

    private var left: Byte = 0
    private var right: Byte = 0

    private fun left(y: Float, height: Float, action: Action): Boolean {
        left = when (action) {
            Action.DOWN, Action.MOVE -> (127 - (y * 256 / height).clamp(0f, 256f)).toInt().toByte()
            Action.UP -> 0
            Action.OTHER -> return false
        }
        update()
        return false
    }

    private fun right(y: Float, height: Float, action: Action): Boolean {
        right = when (action) {
            Action.DOWN, Action.MOVE -> (127 - (y * 256 / height).clamp(0f, 256f)).toInt().toByte()
            Action.UP -> 0
            Action.OTHER -> return false
        }
        update()
        return false
    }

    private fun update() {
        leftView!!.text = left.toString()
        rightView!!.text = right.toString()
        send(left, right)
    }

    protected abstract fun send(left: Byte, right: Byte)
}