puwei/library-push/src/main/java/org/easydarwin/TxtOverlay.kt

package org.easydarwin

import android.graphics.Bitmap
import android.graphics.Color
import android.text.TextUtils
import org.easydarwin.util.YUVUtils
import java.text.SimpleDateFormat

/**
 * Created by John on 2017/2/23.
 */
object TxtOverlay {
    // 提示变化的监听
    private var mTipChangeListener: (() -> Unit)? = null;

    // 上一次展示的提示文字
    private var mLastShowTip = ""

    // 待展示的提示文字
    private var mToDoShowTip = ""

    // 外部调用，设置待显示水印文字
    fun setShowTip(string: String) {
        mToDoShowTip = string
        buildOverlayBitmap()
    }

    // 上一次展示的时间
    private var lastTipUpdateTime: Long = 0

    private const val bmpWidth: Int = 550
    private const val bmpHeight: Int = 330

    // 文字生成的bitmap
    private var bmp: Bitmap? = Bitmap.createBitmap(bmpWidth, bmpHeight, Bitmap.Config.ARGB_8888);

    private var yuv: ByteArray? = null

    // 时间格式化字符串
    private val dateFormat = SimpleDateFormat("yyyy-MM-dd HH:mm:ss")

    private fun buildOverlayBitmap() {
        if (TextUtils.isEmpty(mToDoShowTip)) {
            return
        }
        val currentTimeMillis = System.currentTimeMillis()
        // 限制获取bitmap的频率，保证性能
        if (TextUtils.isEmpty(mLastShowTip) || mToDoShowTip != mLastShowTip || currentTimeMillis - lastTipUpdateTime > 1000) {
            // 记录更新时间和上一次的文字
            lastTipUpdateTime = currentTimeMillis
            mLastShowTip = mToDoShowTip
            // 文字转bitmap
            YUVUtils.generateBitmap(
                bmp,
                dateFormat.format(lastTipUpdateTime) + "@" + mToDoShowTip,
                42,
                Color.WHITE
            )
            yuv = YUVUtils.getYUVByBitmap(bmp)
            mTipChangeListener?.invoke()
        }
    }

    fun getOverlayBitmap(): Bitmap? {
        if (!TextUtils.isEmpty(mToDoShowTip)) {
            return bmp
        }
        return null
    }

    fun getOverlayYuv(): ByteArray? {
        if (!TextUtils.isEmpty(mToDoShowTip)) {
            return yuv
        }
        return null
    }

    fun setTipChangeListener(onChange: () -> Unit) {
        mTipChangeListener = onChange
    }
}